FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Bellomo, P Rago, CE Spencer, CM Wilson, ZJ AF Bellomo, P Rago, CE Spencer, CM Wilson, ZJ TI A novel approach to increasing the reliability of accelerator magnets SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE magnet; reliability; FMEA AB When a very large particle accelerator with about 8000 electromagnets, such as the proposed Next Linear Collider (NLC), has an 85% overall availability goal, then all these magnets and their power supplies must be highly reliable and/or quickly repairable. An interdisciplinary reliability engineering approach, more commonly applied to aircraft and space vehicles, has been taken to design maximum reliability in the NLC main linac quadrupoles, while maintaining magnetic field performance and reducing cost. A specially assembled team of engineers with a variety of experiences with magnets carried out a Failure Mode and Effects Analysis (FMEA) on a standard SLAG quadrupole magnet system. This process helped them identify which components were less reliable. Then they redesigned the quadrupole to avoid all the potential problems. A prototype magnet will be made and tested to ensure that functionality has not been lost. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Bellomo, P (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 2 TC 1 Z9 1 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 284 EP 287 DI 10.1109/77.828230 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700062 ER PT J AU Scanlan, RM Dietderich, DR Higley, HC AF Scanlan, RM Dietderich, DR Higley, HC TI Conductor development for high field dipole magnets SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FL SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconduct, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB ID NBTI SUPERCONDUCTOR; SYSTEM AB Historically, improvements in dipole magnet performance have been paced by improvements in the superconductor available for use in these magnets. The critical conductor performance parameters for dipole magnets include current density, piece length, effective filament size, and cost. Each of these parameters is important for efficient, cost effective dipoles, with critical current density being perhaps the most important. Several promising magnet designs for the next hadron collider or a muon collider require fields of 12 T or higher, i.e. beyond the reach of NbTi. The conductor options include Nb3Sn, Nb3Al, or the high temperature superconductors. Although these conductors have the potential to provide the combination of performance and cost required, none of them have been developed sufficiently at this point to satisfy all the requirements. This paper will review the status of each class of advanced conductor and discuss the remaining problems that require solutions before these new conductors can be considered as practical. In particular, the plans for a new program to develop Nb3Sn and Nb3Al conductors for high energy physics applications will be presented. Also, the development of a multikiloamp Bi-2212 cable for dipole magnet applications will be reported. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 23 TC 5 Z9 5 U1 2 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 EI 1558-2515 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 288 EP 293 DI 10.1109/77.828231 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700063 ER PT J AU Gourlay, SA Bish, P Caspi, S Chow, K Dietderich, DR Gupta, R Hannaford, R Harnden, W Higley, H Lietzke, A Liggins, N McInturff, AD Millos, GA Morrison, L Morrison, M Scanlan, RM AF Gourlay, SA Bish, P Caspi, S Chow, K Dietderich, DR Gupta, R Hannaford, R Harnden, W Higley, H Lietzke, A Liggins, N McInturff, AD Millos, GA Morrison, L Morrison, M Scanlan, RM TI Design and fabrication of a 14 T, Nb3Sn superconducting racetrack dipole magnet SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB Most accelerator magnets for applications in the field range up to 10 T utilize NbTi superconductor and a cosine theta coil design. For fields above 10 T, it is necessary to use Nb3Sn or other strain sensitive superconductors and other coil geometries that are more compatible with these materials. This paper describes our recent efforts to design a series of racetrack coil magnets that will provide experimental verification of an alternative magnet design philosophy, with the near-term goal of reaching a field level of approximately 14 T. The conductor and fabrication issues relevant to building high field, racetrack dipoles utilizing Nb3Sn superconductor and a wind and react approach will also be discussed. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Gourlay, SA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 4 TC 4 Z9 4 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 294 EP 297 DI 10.1109/77.828232 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700064 ER PT J AU Ambrosio, G Andreev, N Arkan, TT Barzi, EAZ Caspi, S Chichili, DR Chow, K Kashikhin, VV Limon, PJ Makarov, A Ozelis, JP Terechkine, I Tompkins, JC Wake, M Yadav, S Yamada, R Yarba, V Zlobin, AV AF Ambrosio, G Andreev, N Arkan, TT Barzi, EAZ Caspi, S Chichili, DR Chow, K Kashikhin, VV Limon, PJ Makarov, A Ozelis, JP Terechkine, I Tompkins, JC Wake, M Yadav, S Yamada, R Yarba, V Zlobin, AV TI Development of the 11 T Nb3Sn dipole model at Fermilab SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB A one meter long Nb3Sn dipole model with 11 T nominal magnetic field in a 43.5 mm bore is being developed at Fermilab in collaboration with LBNL and KEK as part of the R&D efforts for a future Very Large Hadron Collider, This paper describes the magnet design and fabrication procedure as well as summarizes the results of magnetic, mechanical and quench protection analyses. The main parameters of superconducting strand and cable are also reported. C1 FNAL, Batavia, IL USA. LBNL, Berkeley, CA USA. RP Ambrosio, G (reprint author), FNAL, Batavia, IL USA. NR 9 TC 12 Z9 12 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 298 EP 301 DI 10.1109/77.828233 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700065 ER PT J AU Ambrosio, G Andreev, N Chichili, DR Terechkine, I Yadav, S Zlobin, AV Caspi, S Wake, M AF Ambrosio, G Andreev, N Chichili, DR Terechkine, I Yadav, S Zlobin, AV Caspi, S Wake, M TI Mechanical design and analysis of the Fermilab 11 T Nb3Sn dipole model SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB The goal of the Fermilab High Field Magnet (HFM) R&D project is to explore various designs and production technology of a high-field, low-cost Nb3Sn accelerator magnet suitable for a future Very Large Hadron Collider (VLHC). The model under fabrication consists of two-layer shell-type coil with 43.5 mm aperture and cold iron yoke. Fermilab concept of magnet design and fabrication technology involves some specific features such as curing of half-coil with ceramic binder/matrix before reaction, and then simultaneous reaction and impregnation of both half-coils to get a "coil pipe" structure. The coil pipe is mechanically supported by the vertically-split iron yoke locked by two aluminum clamps and a thick stainless steel skin, 2D finite element analysis has been performed to study and optimize the prestress in the coil and in the structural elements at room temperature and at 4.2 K, Model description, material properties and the results of mechanical analysis are reported in this paper. C1 FNAL, Batavia, IL USA. LBNL, Berkeley, CA USA. RP Ambrosio, G (reprint author), FNAL, Batavia, IL USA. NR 7 TC 3 Z9 3 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 306 EP 309 DI 10.1109/77.828235 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700067 ER PT J AU Ambrosio, G Kashikhin, VV Limon, PJ Terechkine, I Yamada, R Zlobin, AV Caspi, S Ogitsu, T Wake, M AF Ambrosio, G Kashikhin, VV Limon, PJ Terechkine, I Yamada, R Zlobin, AV Caspi, S Ogitsu, T Wake, M TI Conceptual design study of high field magnets for very large hadron collider SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB During the last year, Fermilab in collaboration with LBNL and KEK was conducting an extensive design study of a superconducting magnet with a two-layer cosine-theta coil for a post-LHC hadron collider, For the 30-50 mm magnet bore range, two superconducting cable types and various current block arrangements and iron yoke outer diameters were considered. This paper summarizes results of the study including field and force distributions, systematic and random field errors, coil magnetization and iron saturation effects. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ambrosio, G (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 10 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 310 EP 313 DI 10.1109/77.828236 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700068 ER PT J AU Andreev, N Arkan, TT Chichili, DR Kashikin, VV Makarov, A Terechkine, I Yadav, S Yamada, R Zlobin, AV Caspi, S Wake, M AF Andreev, N Arkan, TT Chichili, DR Kashikin, VV Makarov, A Terechkine, I Yadav, S Yamada, R Zlobin, AV Caspi, S Wake, M TI Fabrication and testing of a high field dipole mechanical model SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB As a first step towards the development of a high field Nb3Sn superconducting dipole for a Very Large Hadron Collider (VLHC), a short mechanical model was built and tested at Fermilab, The aim of this work was to develop simpler fabrication techniques and test new structural materials to use in the dipole model. The coil design was based on a two-layer, cos(theta) approach. The end parts were designed using ROXIE magnet optimization program and manufactured using a 6-axis EDM machine. The two layers of each half-coil were wound using one piece of cable without any interlayer splices. After winding, a ceramic matrix was applied to the each half-coil and the coil was cured under compression at 150 degrees C. The two half-coils were then assembled together in a reaction fixture for heat treatment at 450 degrees C for 8 hours. After reaction, the coils were placed in a curing fixture for epoxy impregnation. Finally some mechanical and electrical tests were performed after which the coils were sectioned to check the cable positioning and impregnation quality. This paper summarizes the results and experience obtained from the mechanical model. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Andreev, N (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 314 EP 317 DI 10.1109/77.828237 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700069 ER PT J AU Foster, GW Kashikhin, VS Malamud, E Mazur, P Oleck, A Piekarz, H Fuerst, J Rabehl, R Schlabach, P Volk, J AF Foster, GW Kashikhin, VS Malamud, E Mazur, P Oleck, A Piekarz, H Fuerst, J Rabehl, R Schlabach, P Volk, J TI The 100 kA VLHC transmission line magnet superconducting cable test facility SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB A superconducting transmission line magnet test facility was built and commissioned Fermilab. The test facility is capable of generating a 100 kA current in a 17-meter length short-circuited superconducting loop, as well as driving 15m long test magnets. The current is excited by a room temperature primary winding and iron yoke operated as a current transformer. This approach avoids the expense and difficulty of 100kA current leads, and allows the facility to be Dewar-based. The loop has a replaceable superconductor section 4m long for testing various types of VLHC transmission line cables. The system design, 3D magnetic field analysis, magnetic forte distribution and test results are discussed. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Foster, GW (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 4 TC 1 Z9 1 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 318 EP 321 DI 10.1109/77.828238 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700070 ER PT J AU Ambrosio, G Andreev, N Caspi, S Chow, K Kashikhin, VV Terechkine, I Wake, M Yadav, S Yamada, R Zlobin, AV AF Ambrosio, G Andreev, N Caspi, S Chow, K Kashikhin, VV Terechkine, I Wake, M Yadav, S Yamada, R Zlobin, AV TI Magnetic design of the Fermilab 11 T Nb3Sn short dipole model SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB High field accelerator magnets for a future Very Large Hadron Collider are being developed at Fermilab in collaboration with LBNL, and KEK, The goal of this work is to elaborate a Cost-effective Nb3Sn dipole magnet design and technology which provide the nominal field of 11 T, This paper presents a description of the magnetic design of the first short model including cable and strand parameters, coil and yoke cross-section and magnet end geometry. The results of field distribution and field quality calculations including geometrical and random harmonics, Coil magnetization and iron saturation effects are also reported. C1 FNAL, Batavia, IL USA. LBNL, Berkeley, CA USA. RP Ambrosio, G (reprint author), FNAL, Batavia, IL USA. NR 7 TC 11 Z9 11 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 322 EP 325 DI 10.1109/77.828239 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700071 ER PT J AU Gupta, R Ramberger, S Russenschuck, S AF Gupta, R Ramberger, S Russenschuck, S TI Field quality optimization in a common coil magnet design SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB This paper presents the results of initial field quality optimization of body and end harmonics in a "common coil magnet design" [1-6]. It is shown that a good field quality, as required in accelerator magnets, can be obtained by distributing conductor blocks in such a way that they simulate an elliptical coil geometry. This strategy assures that the amount of conductor used in this block design is similar to that is used in a conventional cosine theta design. An optimized yoke that keeps all harmonics small over the entire range of operation using a single power supply is also presented. The field harmonics are primarily optimized with the computer program ROXIE [7,8]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. CERN, Geneva, Switzerland. RP Gupta, R (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 8 TC 9 Z9 9 U1 1 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 326 EP 329 DI 10.1109/77.828240 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700072 ER PT J AU Sabbi, G Ambrosio, G Andreev, N Barzi, E Bauer, P Ewald, K Limon, P Novitski, I Ozelis, J Higley, H Scanlan, R AF Sabbi, G Ambrosio, G Andreev, N Barzi, E Bauer, P Ewald, K Limon, P Novitski, I Ozelis, J Higley, H Scanlan, R TI Conceptual design of a common coil dipole for VLHC SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB Superconducting magnet technology and cost reduction are key issues in the R&D effort towards a post-LHC, 100 TeV hadron collider. A dipole field of 10-12 T at 4.5 K operating temperature results in acceptable machine length and refrigeration power requirements, and allows taking advantage of synchrotron radiation damping to achieve low beam emittance. In this paper, the conceptual design of a react-and-wind common coil dipole is presented, which aims at these operating parameters with minimum cost and complexity. C1 Fermilab Astrophys Ctr, Batavia, IL USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Sabbi, G (reprint author), Fermilab Astrophys Ctr, Batavia, IL USA. NR 6 TC 4 Z9 4 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 330 EP 333 DI 10.1109/77.828241 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700073 ER PT J AU Ambrosio, G Andreev, N Barzi, E Bauer, P Ewald, K Ozelis, J Sabbi, G Dietderich, D AF Ambrosio, G Andreev, N Barzi, E Bauer, P Ewald, K Ozelis, J Sabbi, G Dietderich, D TI Study of the react and wind technique for a Nb3Sn common coil dipole SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB Fermilab, in collaboration with LBNL, is exploring the use of the react and wind technique for a common coil dipole with a Nb3Sn Rutherford cable. An R&D program on conductor design and magnet technology was begun aiming at an 11 T, 2 layer, 30 mm aperture design operating at 4.5 K, The goal is to explore the feasibility of the react and wind technique for flat coils with a minimum bending radius of 90 mm, In order to improve the understanding of the I-c degradation caused by bending after reaction this effect will be studied on both strands and cables. In this paper we present two techniques to measure the critical current degradation due to bending, both in wires and cables, using standard test facilities. Together with the description of the program we show the results of the first measurements on strands and the layout of the cables that are being produced. C1 Fermilab Astrophys Ctr, Batavia, IL USA. LBNL, Berkeley, CA USA. RP Ambrosio, G (reprint author), Fermilab Astrophys Ctr, Batavia, IL USA. NR 7 TC 8 Z9 8 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 338 EP 341 DI 10.1109/77.828243 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700075 ER PT J AU Horvath, IL Dardel, B Marti, HP Neuenschwander, J Smith, RP Fabbricatore, P Musenich, R Calvo, A Campi, D Cure, B Desirelli, A Favre, G Riboni, PL Sgobba, S Tardy, T Tavares, SSL AF Horvath, IL Dardel, B Marti, HP Neuenschwander, J Smith, RP Fabbricatore, P Musenich, R Calvo, A Campi, D Cure, B Desirelli, A Favre, G Riboni, PL Sgobba, S Tardy, T Tavares, SSL TI The CMS conductor SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB The Compact Muon Solenoid (CMS) is one of the experiments, which are being designed in the framework of the Large Hadron Collider (LHC) project at CERN, The design field of the CMS magnet is 4 T, the magnetic length is 13 m and the aperture is 6 m. This high magnetic field is achieved by means of a 4 layer, 5 modules superconducting coil. The coil is wound from an Al-stabilized Rutherford type conductor. The nominal current of the magnet is 20 kA at 4.5K. In the CMS coil the structural function is ensured, unlike in other existing Al-stabilized thin solenoids, both by the Al-alloy reinforced conductor and the external former. In this paper the retained manufacturing process of the 50-km long reinforced conductor is described. In general the Rutherford type cable is surrounded by high purity aluminium in a continuous co-extrusion process to produce the insert. Thereafter the reinforcement is joined by Electron Beam Welding to the pure Al of the insert, before being machined to the final dimensions. During the manufacture the bond quality between the Rutherford cable and the high purity aluminium as well as the quality of the EB welding are continuously controlled by a novel ultrasonic phased array system. The dimensions of the insert and the final conductor are measured by Laser micrometer. C1 Swiss Fed Inst Technol, Zurich, Switzerland. ACS, Cortaillod, Switzerland. MartiSUPRATEC, Wallisellen, Switzerland. EMPA, Dubendorf, Switzerland. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Ist Nazl Fis Nucl, I-16146 Genoa, Italy. CERN, Geneva, Switzerland. RP Horvath, IL (reprint author), ETH Zurich, Zurich, Switzerland. RI Neuenschwander, Juerg/A-1781-2009 NR 8 TC 12 Z9 12 U1 1 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 395 EP 398 DI 10.1109/77.828256 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700088 ER PT J AU Weggel, RJ AF Weggel, RJ TI Conceptual design of a magnet system to generate 20 T in a 0.15 m diameter bore, employing an inductor precooled by liquid nitrogen SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE pulse magnet; liquid nitrogen; inductor; conical bore; superconducting magnet; flux shielding; optimization AB The research program for an eventual neutrino factory or muon collider needs a magnet of similar to 0.15 m diameter bore to generate similar to 20 T over a length of similar to 0.3 m. Downstream for similar to 3 m the field should fall gradually to similar to 1.25 T, while the bore increases fourfold inversely as the square root of the field. A conventional magnet would require similar to 40 MW; a superconducting or hybrid magnet might cost tens of millions of dollars. An economically feasible system employs a pulse magnet precooled by liquid nitrogen, with two sets of coils energized sequentially. An outer set of coils of similar to 12 tons, energized in similar to 20 s by, a 16 kA; 250 V supply available at Brookhaven National Laboratory, generates a peak field of similar to 9 T and stores similar to 20 MJ. A resistor of similar to 1/4 Omega inserted across the terminals of the set introduces a voltage drop, initially similar to 4 kV, to energize an inner set of coils to similar to 10 kA in similar to 1/4 s. This set adds similar to 13 T to the similar to 7 T remaining from the outer set, whose current has decayed to similar to 12 kk Complicating the design is a superconducting coil once part of the PEP-4 detector at the Stanford Linear Accelerator Center, that begins only similar to 2.2 m downstream and is sensitive to eddy-current Beating by rapid flux changes. Therefore the proposed magnet system includes a conventional de coil of similar to 0.7 MW to distance the pulse magnet from the PEP-4 colt Also, a bucking coil in series with the outer set reduces by an order of magnitude the pulsed flux seen by the PEP-4 colt The bucking coil serves also to reduce the axial force on the PEP-4 cryostat to below its limit of 200 kN. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Weggel, RJ (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 447 EP 450 DI 10.1109/77.828268 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700100 ER PT J AU Sims, J Baca, A Boebinger, G Boenig, H Coe, H Kihara, K Manzo, M Mielke, C Schillig, J Eyssa, Y Lesch, B Li, L Schneider-Muntau, H AF Sims, J Baca, A Boebinger, G Boenig, H Coe, H Kihara, K Manzo, M Mielke, C Schillig, J Eyssa, Y Lesch, B Li, L Schneider-Muntau, H TI First 100 T non-destructive magnet SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE high field; pulsed magnet; 100 tesla AB The first 100 T non-destructive (100 T ND) magnet and power supplies as currently designed are described. This magnet will be installed as part of the user facility research equipment at the National High Magnetic Field Laboratory (NHMFL) Pulsed Field Facility at Los Alamos National Laboratory. The 100 T ND magnet will provide a 100 T pulsed field of 5 ms duration (above 90% of full field) in a 15 mm diameter bore once per hour. Magnet operation will be nondestructive. The magnet will consist of a controlled power outer coil set which produces a 47 T platform field in a 225 mm diameter bore. Located within the outer coil set will be a 220 mm outer diameter capacitor powered insert coil. Using inertial energy storage a synchronous motor/generator will provide ac power to a set of seven ac-dc converters rated at 64 MW/80 MVA each. These converters will energize three independent coil circuits to create 170 MJ of field energy in the outer coil set at the platform field of 47 T. The insert will then be energized to produce the balance of the 100 T peak field using a 2.3 MJ, 18 kV (charged to 15 kV), 14.4 mF capacitor bank controlled with solid-state switches. The magnet will be the first of its kind and the first non-destructive, reusable 100 T pulsed magnet. The operation of the magnet will be described along with special features of its design and construction. C1 Univ Calif Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. NHMFL, Tallahassee, FL 32306 USA. RP Sims, J (reprint author), Univ Calif Los Alamos Natl Lab, Natl High Magnet Field Lab, POB 1663, Los Alamos, NM 87545 USA. RI Mielke, Charles/S-6827-2016 OI Mielke, Charles/0000-0002-2096-5411 NR 8 TC 24 Z9 24 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 510 EP 513 DI 10.1109/77.828284 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700115 ER PT J AU Bacon, J Baca, A Coe, H Kihara, K Manzo, M Schillig, J Sims, J Eyssa, Y AF Bacon, J Baca, A Coe, H Kihara, K Manzo, M Schillig, J Sims, J Eyssa, Y TI First 100 T non-destructive magnet outer coil set SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE high field; pulsed magnet; 100 tesla AB The controlled power outer coil set of the first 100 T non-destructive (100 T ND) magnet Is described. This magnet will be installed as part of the user facility research equipment at the National High Magnetic Field laboratory (NHMFL) Pulsed Field Facility at Los Alamos National Laboratory. The 100 T ND controlled power outer coil set consists of seven nested, mechanically independent externally reinforced coils. These coils, in combination, will produce a 47 T platform field in a 225mm diameter bore. Using inertial energy storage a synchronous motor/generator provides sc power to a set of seven sc-de converters rated at 64 MW/80 MVA each. These converters energize three independent coil circuits to create 170 MJ of field energy in the outer coil set at the platform field of 47 T. Each coil consists of a multi-layer winding of high strength conductor supported by an external high strength stainless steel shell. Coils with the highest magnetic loads will utilize a reinforcing shell fabricated from highly cold worked 301 stainless steel strip. The autofrettage conditioning method will be used to pre-stress the coils and thereby limit conductor and reinforcement strains to the elastic range. The purpose of pre-stressing the coils is to attain a design life of 10,000 full field pulses. The operation and conditioning of the coil set will be described along with special features of its design, magnetic and structural analyses and construction. C1 Univ Calif Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. NHMFL, Tallahassee, FL 32306 USA. RP Bacon, J (reprint author), Univ Calif Los Alamos Natl Lab, Natl High Magnet Field Lab, POB 1663, Los Alamos, NM 87545 USA. NR 2 TC 3 Z9 3 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 514 EP 517 DI 10.1109/77.828285 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700116 ER PT J AU Li, L Lesch, B Eyssa, Y Han, K Walsh, R Schneider-Muntau, H Sims, J Schillig, J Boenig, H Mielke, C Boebinger, G AF Li, L Lesch, B Eyssa, Y Han, K Walsh, R Schneider-Muntau, H Sims, J Schillig, J Boenig, H Mielke, C Boebinger, G TI Insert coil design of the first 100 T non-destructive magnet SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB The design of the capacitor bank driven insert of the first 100 T non destructive magnet is described. The coil is wound with 8 conductor layers, and is internally reinforced with the multiphase alloy MP35N(TM) in combination with a Zylon(TM) fiber/epoxy composite. The deformation of the conductor is limited by the high modulus reinforcements, therefore, the coil will operate in the elastic state after conditioning. This ensures long magnet life. The insert coil will be energized by a 2.3 MJ, 18 kV capacitor bank operating at 15 kV, The mechanical deformation. heating and the magnetic field reduction due to the eddy currents in the MP35N(TM) reinforcement are analyzed. C1 Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Univ Calif Los Alamos Natl Lab, NHMFL, Los Alamos, NM 87545 USA. RP Li, L (reprint author), Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. RI Mielke, Charles/S-6827-2016 OI Mielke, Charles/0000-0002-2096-5411 NR 5 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 518 EP 521 DI 10.1109/77.828286 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700117 ER PT J AU Schillig, J Boenig, H Gordon, M Mielke, C Rickel, D Sims, J Martin, J Williams, R AF Schillig, J Boenig, H Gordon, M Mielke, C Rickel, D Sims, J Martin, J Williams, R TI Operating experience of the United States' National High Magnetic Field Laboratory 60 T Long Pulse magnet SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB The 60 T Long-Pulse (60 T LP) magnet system has provided controlled power magnetic field pulses to experimentalists since August 3, 1998. This magnet system is installed as part of the user facility research equipment at the National High Magnetic Laboratory (NHMFL) Pulsed Field Facility at Los Alamos National Laboratory. The 60 T LP magnet is the first of its kind in the United States and produces the highest field in its class, routinely providing a 60 T pulsed field of 100 ms flat-top duration in a 32mm diameter bore. In addition, numerous other controlled pulse shapes at 60 T and lower fields have been provided. Since the start of commissioning on September 17, 1997 the magnet has been pulsed in excess of 800 times at various field levels. More than 600 magnet pulses have been provided to experiments and almost 400 of these were at 60 T. Operating statistics including coil system and inductance and resistance histories are presented. Operating and maintenance experience and issues are discussed as well as realizable improvements and upgrades to the magnet. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. PLCs Plus, Richland, WA USA. RP Schillig, J (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. RI Mielke, Charles/S-6827-2016 OI Mielke, Charles/0000-0002-2096-5411 NR 2 TC 20 Z9 23 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 526 EP 529 DI 10.1109/77.828288 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700119 ER PT J AU Li, L Rovang, D Lesch, B Pernambuco-Wise, P Schneider-Muntau, HJ AF Li, L Rovang, D Lesch, B Pernambuco-Wise, P Schneider-Muntau, HJ TI Design of a large-bore 60-T pulse magnet for Sandia National Laboratories SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB The design of a new pulsed magnet system for the generation of intense electron beams is presented. Determined by the required magnetic field profile along the axis, the magnet system consists of two coils (Coil #1 and #2) separated by a 32-mm axial gap. Each coil is energized independently. Both coils are internally reinforced with HM Zylon fiber/epoxy composite. Coil #1 made with Al-15 Glidcop wire has a bore of 110-mm diameter and is 200-mm long; it is energized by a 1.3-MJ, 13-kV capacitor bank. The magnetic field at the center of this coil is 30 T. Coil #2 made with CuNb wire has a bore diameter of 45 mm, generates 60 T with a pulse duration of 60 ms, and is powered by a 4.0-MJ, 17.7-kV capacitor bank. We present design criteria, coupling of the magnets, and normal and fault conditions during operation. C1 Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Oceanit Labs Inc, Honolulu, HI USA. RP Li, L (reprint author), Natl High Magnet Field Lab, 1800 E Paul Dirac Dr, Tallahassee, FL 32310 USA. NR 5 TC 0 Z9 0 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 530 EP 533 DI 10.1109/77.828289 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700120 ER PT J AU Painter, T Bole, S Eyssa, Y Dixon, I Williams, V Maier, S Gundlach, S Tozer, S Hascicek, Y Ammerman, C AF Painter, T Bole, S Eyssa, Y Dixon, I Williams, V Maier, S Gundlach, S Tozer, S Hascicek, Y Ammerman, C TI Design of 30 T split-pair pulse coils for LANSCE SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB The NHMFL has designed a high-frequency split-pair coil system for the Los Alamos Neutron Science Center (LANSCE) that can achieve fields up to 30 T for greater than 10(5) cycles and up to 26 T for 10(7) cycles In a 20 mm bore and a 5 mm clear split at the midplane, The magnet system pushes the limits of the technology by requiring a clear split, except for 14 mm of aluminum, and a 2 Hz pulse frequency. The 14 mm of aluminum is in the form of rings required to help support the 1337 MV magnetic load between the two coil halves, The clear split allows the neutrons to travel unobstructed from source to detector. The 2 Hz pulse frequency requires that the coils be continuously cooled with de-ionized water flowing at 15 m/s along the inner diameters of each coil. This paper summarizes the overall design, discusses some of the key features and predicts the coil fatigue performance based on available conductor fatigue properties. The coils are presently being fabricated and scheduled for delivery to the LANSCE in early 2000. C1 Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Painter, T (reprint author), Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 538 EP 541 DI 10.1109/77.828291 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700122 ER PT J AU Li, L Lesch, B Cochran, V Staton, R Tozer, S Schneider-Muntau, H Rickel, D Mielke, C Boebinger, G AF Li, L Lesch, B Cochran, V Staton, R Tozer, S Schneider-Muntau, H Rickel, D Mielke, C Boebinger, G TI High performance pulsed magnets with high strength conductors and high modulus internal reinforcement SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB ID FIELD AB The use of internal reinforcement in pulse magnets has been proven to be an efficient way to obtain reliably very high magnetic fields. An optimum design should be such that both the reinforcement and the conductor reach their failure criteria simultaneously. This requires the mechanical properties of the reinforcement to match those of the conductor under all operating conditions. The decision criterions for the selection of the internal reinforcement materials for different conductors are presented and discussed. Several pulsed magnets with high strength conductors and internal reinforcement with high modulus materials have been designed, fabricated and tested. The performance of these magnets is presented and discussed. C1 Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Univ Calif Los Alamos Natl Lab, NHMFL, Los Alamos, NM 87545 USA. RP Li, L (reprint author), Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. RI Mielke, Charles/S-6827-2016 OI Mielke, Charles/0000-0002-2096-5411 NR 5 TC 14 Z9 16 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 542 EP 545 DI 10.1109/77.828292 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700123 ER PT J AU Jayakumar, RJ Minervini, JV Wohlwend, J Martovetsky, N Thome, RJ AF Jayakumar, RJ Minervini, JV Wohlwend, J Martovetsky, N Thome, RJ TI The USHT-ITER CS model coil program achievements SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB The International Thermonuclear Experimental Reactor (ITER) collaboration has fabricated an 18 layer CS Model Coil (CSMC) designed for producing a13 T peak field at an operating current of 46 kA. A vertical preload structure applies up to 20 MPa on the coil. The US Home Team has designed and fabricated the 10 layer (2 in hand) inner module of the CSMC which consists of 4 layers of high field conductor and 6 layers of moderate field conductor. Each hand of a layer was wound, then corkscrewed to form a two in hand Pager, Compound bends on the leads were formed to provide for joints, tension plates which support the lead loads were welded to the conductor, terminations for the interlayer (layer to busbar) joints were added and the conductor was heat treated. The turns were insulated and then layers assembled with additional insulation to form the precise geometry, the coil was vacuum epoxy impregnated in a mold and the joints were assembled and insulated, The base structure, the upper support structure, superconducting busbars and the He plumbing for the inner module were also fabricated. All these subsystems were shipped to JAERI, Naka, Japan for installation which is complete and cooldown is in progress, The completion of this large, unprecedented and state of art pulsed superconducting magnet will provide the basis for many future developments in large superconducting magnet design and fabrication. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Gen Atom Co, San Diego, CA USA. MIT, Cambridge, MA 02139 USA. RP Jayakumar, RJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 5 TC 9 Z9 9 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 560 EP 563 DI 10.1109/77.828296 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700127 ER PT J AU Heitzenroeder, P Chrzanowski, J Neumeyer, C Fan, HM AF Heitzenroeder, P Chrzanowski, J Neumeyer, C Fan, HM CA NSTX Team TI Chosen solutions to the engineering challenges of the national spherical torus experiment (NSTX) magnets SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE spherical tori; magnets; magnet engineering AB NSTX is one of the largest of a new class of magnetic plasma research devices known as spherical tori (ST), The plasma in a ST is characterized by its almost spherical shape with a slender open cylindrical region through its vertical axis. The so-called "center stack" is located in this region. It contains magnetic windings to confine the plasma, induce the plasma current, and shape the plasma. This paper describes the engineering challenges of designing the center stack magnets to meet their operational requirements within this constrained space. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Heitzenroeder, P (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 4 TC 0 Z9 0 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 618 EP 623 DI 10.1109/77.828310 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700141 ER PT J AU McConnell, BW AF McConnell, BW TI Transformers - A successful application of high temperature superconductors SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB With the exception of core steel and improvements in insulation, power transformers have changed little in the last fifty years. In general, modern power transformers larger than 10 MVA have full load efficiencies exceeding 99% and are routinely subjected to a form of life-cycle cost evaluation as a part of the purchase process. However, resistive losses in the windings constitute a significant proportion of losses at full load and the desire to further economically reduce these losses using superconducting windings has been an elusive goal for greater than a quarter century. Using high temperature superconducting (HTS) windings this goal is now within reach both technically and economically. Major HTS transformer projects are underway in Europe, Japan and the United States with all projects reporting success in their initial phases. With the desire for improved efficiency and lower losses within technical reach, additional benefits such as reduced size and weight, improved fire safety, overload without loss of transformer life and improved system dynamics through lower impedance and controlled fault current levels have also been identified. These additional benefits may well prove to be significantly more important to the applications of HTS transformers than improved efficiency through loss reduction in the windings. This paper summarizes the status of current HTS transformer projects and the remaining economic and technical challenges that must be met. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP McConnell, BW (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 11 TC 11 Z9 11 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 716 EP 720 DI 10.1109/77.828332 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700163 ER PT J AU Hanai, S Wachi, Y Shimada, M Ono, M Tezuka, M Hamajima, T Martovetsky, N Zbasnik, J Manahan, R Moller, J Ishio, K Isono, T Tsuji, H Yamamoto, M Takano, I Himeno, T Shinoda, K Satow, T AF Hanai, S Wachi, Y Shimada, M Ono, M Tezuka, M Hamajima, T Martovetsky, N Zbasnik, J Manahan, R Moller, J Ishio, K Isono, T Tsuji, H Yamamoto, M Takano, I Himeno, T Shinoda, K Satow, T TI Cyclic and mechanical test results of the 100kWh SMES model coil SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE SMES; superconducting magnet; mechanical test; cyclic test AB The long term reliability of the SMES model coil for the 100kWh SMES pilot plant was investigated in 1000 cycles cyclic test in the test facility of the Lawrence Livermore National Laboratory (LLNL) in 1998, in collaboration between Japan and the United States of America. The coil parameters such as coil inductance, magnetic field and AC loss were measured before and after the cyclic test. They did not change. The coil was successfully charged up to 40.53 kA in the mechanical performance test, which gave mechanically the same conditions as in the SR IES pilot plant at rated current. After all performance tests, the coil was checked visually and electrically, and no degradation was observed. Mechanical reliability of the SMES model coil was verified in the performance tests. The obtained technical results encourage us to recommend construction of the pilot plant. C1 Toshiba Corp, Yokohama, Kanagawa, Japan. Yamaguchi Univ, Yamaguchi 753, Japan. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Japan Atom Energy Res Inst, Naka, Ibaraki 31101, Japan. Int Superconduct Technol Ctr, Tokyo 135, Japan. Chubu Elect Power Co Inc, Nagoya, Aichi, Japan. Natl Inst Fus Sci, Gifu, Japan. RP Hanai, S (reprint author), Toshiba Corp, Yokohama, Kanagawa, Japan. NR 8 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 808 EP 811 DI 10.1109/77.828354 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700185 ER PT J AU Hamajima, T Hanai, S Wachi, Y Kyoto, M Shimada, M Ono, M Shimada, K Kushida, L Tezuka, M Martovetsky, N Zbasnik, J Moller, J Takahashi, Y Matsui, K Isono, T Yamamoto, M Takano, I Himeno, T Hirano, N Shinoda, K Satow, T AF Hamajima, T Hanai, S Wachi, Y Kyoto, M Shimada, M Ono, M Shimada, K Kushida, L Tezuka, M Martovetsky, N Zbasnik, J Moller, J Takahashi, Y Matsui, K Isono, T Yamamoto, M Takano, I Himeno, T Hirano, N Shinoda, K Satow, T TI AC loss performance of the 100 kWh SMES model coil SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB ID CABLE; LIMITATION AB AC loss tests of the SMES model coil for 100kWh SMES pilot plant were carried out at Lawrence Livermore National Laboratory (LLNL) in 1998, in collaboration between Japan and the USA. The AC loss results at LLNL were in good agreement with those obtained at the Japan Atomic Energy Research Institute (JAERI) in 1996. The coupling loss in the coil could be described by two components with a short time constant (0.22s) and a long time constant (30s). The short time constant was in good agreement with that measured in a short sample. The signals of Hall probes, mounted on the surface of the coil, revealed that the induced loop currents in the conductor decayed with long time constants. At least two long time constants were observed: about 4s and 100s. The long time constant was also identified by the observation of voltage decay after the coil discharge. These loops result in the additional AC loss in the coil. Effect of lateral force in the cable on losses was studied as well. An improved conductor aiming to reduce the AC loss was-designed, fabricated and wound in a small coil. The measured AC loss in the small coil made of the improved conductor was about 1/6 of the SMES model coil per strand volume. C1 Yamaguchi Univ, Ube, Yamaguchi 7558611, Japan. Toshiba Corp, Tsurumi Ku, Yokohama, Kanagawa 2300045, Japan. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Japan Atom Energy Res Inst, Naka, Ibaraki 3110193, Japan. Int Superconduct Technol Ctr, Tokyo 1050004, Japan. Chubu Elect Power Co Inc, Midori Ku, Nagoya, Aichi 4598001, Japan. Natl Inst Fus Sci, Toki 5095292, Japan. RP Hamajima, T (reprint author), Yamaguchi Univ, Ube, Yamaguchi 7558611, Japan. NR 14 TC 10 Z9 10 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 812 EP 815 DI 10.1109/77.828355 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700186 ER PT J AU Leung, E Burley, B Chitwood, N Gurol, H Miyata, G Morris, D Ngyuen, L O'Hea, B Paganini, D Pidcoe, S Haldar, P Gardner, M Peterson, D Boenig, H Cooley, J Coulter, Y Hults, W Mielke, C Roth, E Smith, J Ahmed, S Rodriguez, A Langhorn, A Gruszczynski, M Hoehn, J AF Leung, E Burley, B Chitwood, N Gurol, H Miyata, G Morris, D Ngyuen, L O'Hea, B Paganini, D Pidcoe, S Haldar, P Gardner, M Peterson, D Boenig, H Cooley, J Coulter, Y Hults, W Mielke, C Roth, E Smith, J Ahmed, S Rodriguez, A Langhorn, A Gruszczynski, M Hoehn, J TI Design & development of a 15 kV, 20 kA HTS fault current limiter SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB A 15 kV class high temperature superconducting fault current limiter was developed as part of a Department of Energy Superconductivity Partnership Initiative (SPI) Phase II effort. This is an inductive/electronic fault current limiter (FCL) that can double as a fast sub-cycle solid state breaker. The said device was shipped to Southern California Edison (SCE) Center Substation at Norwalk, CA from General Atomics on June 15, 1999. Preliminary high voltage and high current testing was conducted. The pre-commercial FCL unit houses three of the world's largest Bi-2223 coils (solenoids each with an outside diameter of 1 m and a coil length of 0.75 m), collaborated by GA and IGC. These coils will operate at 35 K and be able to carry a continuous DC current of 2000 A as well as an AC pulsed current of 9000 A. Detailed specification of the FCL device and a brief description of;its various subsystems will be given. Finally, test results at Center Substation will be summarized and future work outlined. This Phase II FCL device is important as it has the potential to become the first major commercial product for HTS power utility application. C1 Gen Atom Co, San Diego, CA 92186 USA. Intermagnet Gen Corp, Latham, NY USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. So Calif Edison, Rosemead, CA USA. StarTech Inc, San Diego, CA USA. Innovat Engn Solut, San Diego, CA USA. RP Leung, E (reprint author), Gen Atom Co, San Diego, CA 92186 USA. RI Cooley, Jason/E-4163-2013; Mielke, Charles/S-6827-2016 OI Mielke, Charles/0000-0002-2096-5411 NR 5 TC 34 Z9 41 U1 0 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 832 EP 835 DI 10.1109/77.828360 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700191 ER PT J AU Leung, E Burley, B Haldar, P Morris, D Langhorn, A Coulter, Y Roth, E Gruszczynski, M AF Leung, E Burley, B Haldar, P Morris, D Langhorn, A Coulter, Y Roth, E Gruszczynski, M TI Testing of the world's largest Bi-2223 high temperature superconducting coil SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB Three large high temperature superconducting coils were used in the 15 kV class Fault Current Limiter (FCL), designed and fabricated as part of a Phase II US DoE Superconductivity Partnership Program. Each of these solenoids measures 1.0 m in diameter and 0.75 m long. Each coil is designed to carry 2000 Adc and withstand an ac ripple of 16 A at 120 Hz. Each coil is wound from 15 km of Bi-2223 sliver tapes and has an inductance of 4 mil. These coils were co-designed by General Atomics (GA) and Intermagnetics General Corporation (IGC) and constructed at the latter. GA provided the cryogenics and auxiliary components for the overall cryomagnetic assembly, Each coil is cooled by three cryocoolers and the designed operating temperature is 35 K. This paper presents the design specification of these coils. A brief description of the cryogenic & auxiliary setup is given and results from the thermal & electrical testing, that took place at General Atomics from April 13 to May 20, 1999, are presented. C1 Gen Atom Co, San Diego, CA 92186 USA. Intermagnet Gen Corp, Latham, NY USA. StarTech Inc, San Diego, CA USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Innovat Engn Solut, San Diego, CA USA. RP Leung, E (reprint author), Gen Atom Co, San Diego, CA 92186 USA. NR 7 TC 8 Z9 8 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 865 EP 868 DI 10.1109/77.828368 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700199 ER PT J AU Brown, BC Brown, CN Foster, GW Fowler, WB Glass, HD Harding, DJ Jackson, GP May, MP Nicol, TH Pruss, S Schlabach, P Volk, JT AF Brown, BC Brown, CN Foster, GW Fowler, WB Glass, HD Harding, DJ Jackson, GP May, MP Nicol, TH Pruss, S Schlabach, P Volk, JT TI Time dependence and temperature stability of the permanent magnets for the fermilab antiproton recycler ring SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB The Fermilab Recycler Ring, part of the Main Injector upgrade(i), is an 8 GeV storage ring consisting of 362 gradient magnets, 109 quadrupoles, 8 mirror magnets, and 5 Lambertsons. The field is driven by strontium ferrite permanent magnets and shaped by precision pole pieces. Temperature dependence of the ferrite is compensated by the use of Ni (30%) Fe (70%) alloy operating near its Curie point. Temperature stability is held to within 0.004%/degrees C rms. over the operating range of 25 to 35 C. Tighter stability requirements (0.001%/degrees C) for the high beta quadrupoles are met by active thermal control using heating blankets. Longitudinal uniformity is obtained by distribution of the compensator and ferrite throughout the magnet. Field strength in the magnets are adjusted to be within 0.05% of the design field. The Higher harmonics contribute less than 0.01% of the primary field measured at a radius of 25.4 mm. For the gradient magnets custom end shims are made to adjust the harmonics; the field is adjusted by adding or subtracting ferrite. The loss of magnetization is logarithmic in time with a Delta(M-2/M-1) = 9.0 x 10(-4) *log (t(2)/t(1)), corresponding to a 0.35% loss of field over the expected operating life of 20 years. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Brown, BC (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 879 EP 882 DI 10.1109/77.828371 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700202 ER PT J AU Post, RF Ryutov, DD AF Post, RF Ryutov, DD TI The Inductrack: A simpler approach to magnetic levitation SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB Arising out of research at the Lawrence Livermore National Laboratory on passive magnetic bearings, a new magnetic levitation system, the Inductrack, has been developed and tested at model scale. The system employs special arrays of permanent magnets (Halbach arrays) on the moving car. The magnetic field from the arrays induces repelling currents in a close-packed array of shorted circuits in the track. Above a low transition speed (a few kilometers per hour), levitation forces approach a constant value, while drag forces decrease inversely with speed, with L/D reaching 200:1 or more at operating speeds. The high magnetic efficiency of the Halbach arrays, plus the use of close-packed track circuits, results in levitating forces approaching 40 metric tonnes per square meter (using NdFeB permanent magnet arrays, whose weight in typical cases is a few percent of the levitated weight). The system is passively stable: Only motion is required for levitation. Failure of the drive system only results in the train slowing down and settling onto auxiliary wheels ata low speed. A detailed theoretical analysis of the Inductrack was made, on the basis of which a smalt-scale model was constructed and operated. The Laboratory is now building a new small-scale model system (under NASA sponsorship) to demonstrate the acceleration rates and speeds (10-g and Mach 0.4 in the model) needed to magnetically launch rockets. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Post, RF (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 3 TC 21 Z9 29 U1 3 U2 13 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 901 EP 904 DI 10.1109/77.828377 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700208 ER PT J AU Barzi, E Boffo, C Limon, PJ Ozelis, JP Yamada, R Zlobin, AV Gregory, E Pyon, T Wake, M AF Barzi, E Boffo, C Limon, PJ Ozelis, JP Yamada, R Zlobin, AV Gregory, E Pyon, T Wake, M TI Heat treatment study of Nb3Sn strands for the Fermilab's high field dipole model SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB Fermilab is developing high field superconducting dipole magnets based on Nb3Sn for a post-LHC very large hadron collider (VLHC). The first prototype is a 1 meter long two-layer shell-type (cos-theta) coil with a nominal field of 11T, A keystoned Rutherford-type cable made of 28 Nb3Sn strands of 1mm in diameter is used, The development of high J(c) multifilamentary Nb3Sn strands with low magnetization is an important step of this program, To achieve this goal, strand R&D is actively pursued by Fermilab and IGC using the internal tin process. Conductor designs, heat treatment studies, and results of measurements, including I-c, n-value, RRR, magnetization, and chemical analyses, are presented. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. IGC AS, Waterbury, CT USA. RP Barzi, E (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 4 TC 0 Z9 0 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1000 EP 1003 DI 10.1109/77.828400 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700231 ER PT J AU Truchan, TG Rountree, FH Lanagan, MT McClellan, SM Miller, DJ Goretta, KC Tomsic, M Foley, R AF Truchan, TG Rountree, FH Lanagan, MT McClellan, SM Miller, DJ Goretta, KC Tomsic, M Foley, R TI Preparation of nickel substrates for coated conductors SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE Ni; superconductors; texture ID TAPES; FILMS AB Polycrystalline Ni has been used as a substrate for high-current, coated YBa2Cu3Ox superconductors. For many conductors, Ni is rolled to large deformation and annealed to produce a cube texture. In this study, Ni was rolled to >95% reduction and annealed in 5% H-2/95% He at 300-1000 degrees C for various times. The resulting substrates were examined by scanning electron microscopy, X-ray and electron diffraction, and surface interferometry. Key determinations for the Ni were extent of in-plane and out-of-plane texture, surface smoothness, and grain size. The extent of texture was approximately independent of annealing temperature and increased slightly with annealing time. Annealing at temperatures >600 degrees C increased surface roughness, primarily due to grain-boundary grooving. Grain growth was fastest at 1000 degrees C and was proportional to time to the 0.1 power. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Eurus Technol Inc, Tallahassee, FL USA. IIT, Chicago, IL 60616 USA. RP Truchan, TG (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 15 TC 9 Z9 9 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1130 EP 1133 DI 10.1109/77.828432 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700263 ER PT J AU Prorok, BC Park, JH Goretta, KC Balachandran, U McNallan, MJ AF Prorok, BC Park, JH Goretta, KC Balachandran, U McNallan, MJ TI Hardness and microstructure of internally oxidized silver alloys SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE internal oxidation; Ag alloys; high-temperature superconductors ID IN-TUBE TAPES; AG-MG ALLOYS; OXIDATION; DEFORMATION AB Alloys of Ag, Ag/1.12 at.% Mg, and Ag/0.25 at.% Mg-0.25 At.%Ni were internally oxidized at 450 to 825 degrees C and their hardnesses and:microstructures were observed. Microhardness profiles showed that hardness was high near the surface and decreased with depth into the sample. Microstructures contained regions of small and large grains, where region sizes were dependent on treatment temperature. Transitions between small- and large-grained regions were abrupt. Treatments at higher temperatures failed to alter grain structure, indicating that Mg-O clusters had indeed pinned the grain boundaries. Clustering was shown to affect the hardness of oxidized alloys, not only by inhibiting grain growth, but also by inhibiting dislocation motion. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Univ Illinois, Chicago, IL 60607 USA. RP Prorok, BC (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Prorok, Barton/A-7404-2010 NR 12 TC 6 Z9 6 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1178 EP 1181 DI 10.1109/77.828444 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700275 ER PT J AU Sumption, MD Scanlan, RM Nijhuis, A Collings, EW AF Sumption, MD Scanlan, RM Nijhuis, A Collings, EW TI AC loss and contact resistance in copper-stabilized Nb3Al Rutherford cables with and without a stainless steel core SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB Calorimetric measurements of AC loss and hence interstrand contact resistance (ICR), were measured on three samples of Rutherford cable wound with Cu-stabilized jelly-roll type unplated Nb3Al strand. One of the cable types was furnished with a thin core of AISI 316L stainless steel and the other two were both uncored but insulated in different ways. The cables were subjected to a room-temperature-applied uniaxial pressure of 12 MPa that was maintained during the reaction heat treatment (RHT), then vacuum impregnated with CTD lot epoxy, and repressurized to 100 MPa during AC-loss measurement. The measurements were performed at 4.2 K in a sinusoidal field of amplitude 400 mT at frequencies of 1 to 90 mHz (no DC-bias field) that was applied both perpendicular and parallel to the face of the cable (the face-on, FO, and edge-on, EO, directions, respectively). For the cored cable the FO-measured effective ICR (FO-ICR), was 5.27 mu Omega. Those for the uncored cables were less than 0.08 mu Omega. AS shown previously for NbTi- and Nb3Sn-based Rutherford cables, the FO-ICR can be significantly increased by the insertion of a core, although in this case it is still below the range recommended for accelerator-magnet use. Postmeasurement dissection of one of the cables showed that the impregnating resin had permeated between the strands and coated the core with a thin, insulating layer excepting for some sintered points of contact. In the uncored cables the: strands were coated with resin except for the points of interstrand contact. It is suggested that in the latter case this tendency for partial coating leads to a processing-sensitive FO-ICR. C1 OSU, Dept Mat Sci, Columbus, OH USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. Univ Twente, NL-7500 AE Enschede, Netherlands. RP Sumption, MD (reprint author), OSU, Dept Mat Sci, Columbus, OH USA. RI Sumption, Mike/N-5913-2016 OI Sumption, Mike/0000-0002-4243-8380 NR 22 TC 3 Z9 3 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1196 EP 1199 DI 10.1109/77.828448 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700279 ER PT J AU Han, K Baca, A Coe, H Embury, J Kihara, K Lesch, B Li, L Schillig, J Sims, J Van Sciver, S Schneider-Muntau, HJ AF Han, K Baca, A Coe, H Embury, J Kihara, K Lesch, B Li, L Schillig, J Sims, J Van Sciver, S Schneider-Muntau, HJ TI Material issues in the 100 T non-destructive magnet SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE high strength conductor; conductivity ID COPPER COMPOSITE WIRES; HIGH-STRENGTH; CONDUCTIVITY AB The effort in materials program related to the first 100 T non-destructive (100 T ND) magnet has been concentrated on four areas: a.) development of the fabrication routes for various conductive wires in collaboration with other institutes and industrial partners, b.) investigation of the properties of a variety of candidate high strength high conductivity materials, c.) selection of the reinforcement materials for the coils and development of fabrication routes for these materials, d.) characterization of the commercially available insulation materials. This paper deals with the conductor issues. The properties and the microstructure of Cu-Ag, UNS-C157XX (Cu-Al2O3), Cu+Stainless Steels (SS) and Cu-Nb composites have been investigated for their potential use as conductors in pulsed high field magnets, These conductors demonstrate a combination of good conductivity, high strength, adequate workability, and the availability of final section sizes needed for the magnet design. Examination of the initial portion of the stress strain curve of cold worked conductors reveals that the internal stresses developed during the fabrication influence the mechanical response of the materials. Thus, the properties of the drawn materials have been measured as a function of cyclic loading and thermal annealing cycles, and the cyclic properties are related to the internal stresses. C1 NHMFL, Tallahassee, FL USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Han, K (reprint author), NHMFL, Tallahassee, FL USA. NR 11 TC 9 Z9 10 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1277 EP 1280 DI 10.1109/77.828468 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700299 ER PT J AU Jayawardana, S Garcia, GV Nakotte, H Clausen, B Bourke, M AF Jayawardana, S Garcia, GV Nakotte, H Clausen, B Bourke, M TI Finite element modeling of anisotropic properties of Cu-Ag metal matrix composites SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB ID WIRES AB This research investigated the sensitivity of the mean phase strains in a heavily drawn copper-silver fiber composite to the inherent mechanical anisotropies resulting from the texture produced by the drawing process. The work performed here is a precursor to the neutron diffraction experiments to be performed to advance the understanding of the residual stress development during the fabrication process and how these residual strains change as a function of loading. Copper-Silver (Cu-Ag) metal matrix composites are used as high strength conductors for high performance pulse magnets. To produce the filamentary nature and extreme work hardening a cold-working co-deformation fabrication process is used which in turn induces crystallographic alignment of Ag fibers and Cu matrix. In the limiting case the material behavior is close to single-crystalline Ag fibers embedded in single-crystalline Cu matrix. Since this means that the mechanical elastic properties will be strongly anisotropic we investigated the sensitivity of the mean phase strains to the degree of anisotropy using a three dimensional finite element model. The anisotropic elastic properties of the Ag and Cu were incorporated. Several different loading conditions were applied. Results of the various loading conditions were then used to obtain an estimate of the mean phase strains of the composite. C1 New Mexico State Univ, Las Cruces, NM 88003 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Jayawardana, S (reprint author), New Mexico State Univ, Las Cruces, NM 88003 USA. RI Clausen, Bjorn/B-3618-2015 OI Clausen, Bjorn/0000-0003-3906-846X NR 8 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1281 EP 1283 DI 10.1109/77.828469 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700300 ER PT J AU Brandao, L Han, K Embury, JD Walsh, R Toplosky, V VanSciver, S AF Brandao, L Han, K Embury, JD Walsh, R Toplosky, V VanSciver, S TI Development of high strength pure copper wires by cryogenic deformation for magnet applications SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE cryogenic deformation; conductor; conductivity ID CRYSTALS AB A high strength pure copper conductor was fabricated by a cryogenic drawing process at 77 K where the dynamic recovery of copper was reduced. With this method, drawn pure copper wire achieved a strength level of 580 MPa and a conductivity of more than 96% IACS at room temperature. This strength level is about 45 % higher than that obtainable by an equivalent room temperature deformation of copper. The material had a strength level of 680 MPa at 77 K and the resistivity ratio was larger than six. The interesting new basic science concerns the understanding of both strain hardening at low temperature, the attainment of high strength due to the stable accumulation of very high densities of dislocations, the change of the work hardening rate induced by cryogenic deformation, and the texture development in cryogenic deformation. In addition, the methodology has the potential to link the development of new approaches to materials selection and production to specific design needs in a variety of magnets. The potential of cryogenic deformation for the development of high strength conductors of pure copper is discussed in this paper. C1 NHMFL, Tallahassee, FL USA. Inst Mil Engn Rio de Janeiro, Rio De Janeiro, Brazil. Univ Calif Los Alamos Natl Lab, NHMFL, Los Alamos, NM USA. McMaster Univ, Hamilton, ON, Canada. RP Brandao, L (reprint author), NHMFL, Tallahassee, FL USA. RI Brandao, Luiz Paulo/B-2714-2013 OI Brandao, Luiz Paulo/0000-0002-2623-648X NR 7 TC 11 Z9 11 U1 2 U2 12 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1284 EP 1287 DI 10.1109/77.828470 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700301 ER PT J AU Chichili, DR Arkan, TT Ozelis, JP Terechkine, I AF Chichili, DR Arkan, TT Ozelis, JP Terechkine, I TI Investigation of cable insulation and thermo-mechanical properties of epoxy impregnated Nb3Sn composite SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB Within the framework of the Fermilab high field magnet program, cable insulation and thermo-mechanical properties of epoxy impregnated Nb3Sn composite were studied, As a part of cable insulation development, a new wrappable ceramic insulation was investigated to understand its mechanical properties and its influence on magnet fabrication technology. Measurements of modulus of elasticity and Poisson's ratio of Nb3Sn composite made out of ten-stack samples were performed under compression at room temperature and at 4.2 K. The results from both monotonic and cyclic loading tests are presented. Finally, measurements of the coefficient of thermal contraction for the composite using strain gauges is discussed. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Chichili, DR (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 5 TC 26 Z9 26 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1317 EP 1320 DI 10.1109/77.828478 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700309 ER PT J AU Prestemon, S Miller, J Eyssa, Y Green, M AF Prestemon, S Miller, J Eyssa, Y Green, M TI Magnet system design with cost optimization SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE magnet systems; design optimization; cost optimization AB The problem of optimizing the design of magnet systems to simultaneously satisfy a set of constraint equations for field, geometry, protection, and stability while minimizing the total system cost is considered. A mathematical description of the problem is given, along with details concerning possible constraint algorithms and cost functions. Rules for the optimal selection of magnet technology (potted, ventilated, and cable-in-conduit coils) are presented. The resulting sets of equations can be solved by different numerical methods; the final choice is based on considerations of functional form as well as computational speed and accuracy. Depending on the choice of constraint equations, the resulting problem may or may not be smooth, and may or may not admit multiple minima. The choice of minimization algorithm can be tailored to the situation at hand to yield optimal performance. We present results pertaining to an alternating-field solenoid system being considered by the MuCool collaboration. The system design requires consideration of field profile, magnet stability, magnet structure, and protection, as well as total cost. A key application of the optimization code is the analysis of cost trade-off with respect to the imposed constraints, and examples are given in the alternating-solenoid case. C1 Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Prestemon, S (reprint author), Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. NR 5 TC 1 Z9 1 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1356 EP 1359 DI 10.1109/77.828489 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700320 ER PT J AU Yadav, S Kerby, J Ozelis, JP AF Yadav, S Kerby, J Ozelis, JP TI Analysis of parameters affecting beam gauge performance SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB Beam gauges have been used in the last decade or so far measuring the internal azimuthal compressive coil stresses in superconducting magnets, In early model Large Hadron Collider Interaction Region (LHC IR) quadrupoles tested at Fermilab, the beam gauges indicated excessively high amounts of inner and outer coil prestress during the collaring process, inconsistent with the coil size and modulus data. In response to these measurements, a simple mechanics based quantitative understanding of different factors affecting beam gauges has been developed. A finite element model with contact elements and non-linear material behavior, confirmed with experimental results, was developed. The results indicate that a small plastic deformation of either the beam or the backing plate can cause significant errors in the measured stress values. The effect of variations in coil modulus and support boundary conditions on beam gauge performance are also discussed. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Yadav, S (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1399 EP 1402 DI 10.1109/77.828500 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700331 ER PT J AU Datskov, V Petrova, L Bunzarov, Z Demko, J Augustinowicz, S AF Datskov, V Petrova, L Bunzarov, Z Demko, J Augustinowicz, S TI Long-life cryogenic thermometry in particle accelerators and other demanding applications SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB A review of some research on the long-term stability of platinum and carbon thermometers under the working conditions of superconducting magnets for accelerators, as a function of magnetic fields, irradiation, cyclical cooling and heating, and vibration, is conducted, Results with TVO carbon-ceramic thermometers are presented for an Ii-year period,The technology for training and selecting stable thermometers that are capable of ensuring precise measurements of temperature in the 1.6-350 K range during 10-15 years in the harsh working conditions of accelerator and other installations is offered. Some recommendations for reducing the influence of the thermometer production process, thermometer mounting, and places of attachment on the accuracy of cryogenic thermometers are given. C1 Joint Inst Nucl Res, Dubna, Moscow Region, Russia. Oak Ridge Natl Lab, Oak Ridge, TN USA. Dynacs Co, Kennedy Space Ctr, FL USA. RP Datskov, V (reprint author), Joint Inst Nucl Res, Dubna, Moscow Region, Russia. NR 17 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1403 EP 1406 DI 10.1109/77.828501 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700332 ER PT J AU Brown, BC Glass, JDHD Harding, DJ Martin, PS Mazur, PO Mishra, CS Orris, DF Sim, JW Tompkins, JC Trombly-Freytag, K Walbridge, DGC AF Brown, BC Glass, JDHD Harding, DJ Martin, PS Mazur, PO Mishra, CS Orris, DF Sim, JW Tompkins, JC Trombly-Freytag, K Walbridge, DGC TI Magnetic field measurements of Fermilab Main Injector dipoles SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB Measurements of the Fermilab Main Injector dipoles using a partially redundant system of integrated and point measurements were carried out for quality assurance. Additional special measurements studied the hysteretic field strength. Results from these measurements will be presented. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Brown, BC (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 7 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1431 EP 1434 DI 10.1109/77.828508 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700339 ER PT J AU Barlow, DB AF Barlow, DB TI Rotating coil measurement system for the APT/LEDA CCDTL quadrupole magnets SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB A rotating coil measurement system has been developed to characterize the magnetic properties of the Coupled Cavity Drift Tube Linac (CCDTL) quadrupole magnets for the Accelerator Production of Tritium - Low Energy Demonstration Accelerator (APT/LEDA) at the Los Alamos Neutron Science Center (LANSCE). The setup is designed to measure the quadrupole gradient-length product with an absolute error of less than 0.25%, and to determine the relative multipole content of the quadrupole field with an error of less than 0.05% of the quadrupole at a radius of 80% of the aperture. The bench for the system consists of a granite surface plate with a pair of rails attached on which the magnet and rotating coil supports rest. The coil is turned by a DC gear motor. The signal is routed through a slipring to a digital voltage integrator triggered by an incremental encoder attached to one end of the coil. Two different rotating coils were designed and fabricated for the system, The first coil is a conventional radially-wound harmonic coil that;provides a good measure of the relative quadrupole strength and harmonic content, while the second coil is a specially designed printed circuit coil that can accurately measure the quadrupole gradient-length product. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Barlow, DB (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 2 TC 4 Z9 4 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1447 EP 1449 DI 10.1109/77.828512 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700343 ER PT J AU DiMarco, J Glass, H Schlabach, P Sylvester, C Tompkins, JC Krzywinski, J AF DiMarco, J Glass, H Schlabach, P Sylvester, C Tompkins, JC Krzywinski, J TI Influence of mechanical vibrations on the field quality measurements of LHC interaction region quadrupole magnets SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB AB The high gradient quadrupole magnets being developed by the US-LHC Accelerator Project for the LHC Interaction Regions have stringent field quality requirements. The field quality of these magnets will be measured using a rotating coil system presently under development. Mechanical vibrations of the coil during field quality measurements are of concern because such vibrations can introduce systematic errors in measurement results. This paper presents calculations of the expected influence of vibrations on field quality measurements and a technique to measure vibrations present in data acquired with standard "tangential-style" probes. Measured vibrations are reported and compared to simulations. Limits on systematic errors in multipole measurements are discussed along with implications for probe and measurement system design. C1 Fermilab, Batavia, IL 60510 USA. Polish Acad Sci, Inst Phys, Warsaw, Poland. RP DiMarco, J (reprint author), Fermilab, Batavia, IL 60510 USA. NR 3 TC 1 Z9 1 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1458 EP 1461 DI 10.1109/77.828515 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700346 ER PT J AU Ghosh, A Jain, A Muratore, J Parker, B Sampson, W Wanderer, P Willen, E AF Ghosh, A Jain, A Muratore, J Parker, B Sampson, W Wanderer, P Willen, E TI High field magnet program at Brookhaven National Laboratory SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE superconducting magnets; accelerators; Brookhaven National Laboratory; RHIC; LHC; DESY; short-sample; Nb3Sn; HTS; NbTi AB The magnet program at Brookhaven National Laboratory (BNL) is focussed on superconducting magnets for particle accelerators. The effort includes magnet production at the laboratory and in industry, magnet R&D, and test facilities for magnets and superconductors. Nearly 2000 magnets dipoles, quadrupoles, sextupoles and correctors for the are and insertion regions - were produced for the Relativistic Heavy Ion Collider (RHIC), which is being commissioned. Currently, production of helical dipoles for the polarized proton program at RHIC, insertion region dipoles for the Large Hadron Collider (LHC) at CERN, and an insertion magnet system for the Hadron-Elektron-Ring-Analage (HERA) collider at Deutsches Elektronen-Synchrotron (DESY) is underway. The R&D effort is exploring dipoles with fields above 10 T for use in post-LHC colliders. Brittle superconductors - Nb3Sn or HTS - are being used for these magnets. The superconductor test facility measures short-sample currents and other characteristics of samples up to 1 m in length, in liquid and superfluid helium, in dipole fields above 7.5 T at 4.2 K (8.7 T at 1.9 K), and up to 25 kA. This facility performed the short-sample testing of the productions runs of NbTi wires and cables for the HERA-p and RHIC magnets, and is preparing for similar work for the LHC project. The staff also tests samples of superconductors from government laboratories and industry around the world. C1 Brookhaven Natl Lab, RHIC Project, Upton, NY 11973 USA. RP Ghosh, A (reprint author), Brookhaven Natl Lab, RHIC Project, Upton, NY 11973 USA. NR 7 TC 0 Z9 0 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1534 EP 1537 DI 10.1109/77.828534 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700365 ER PT J AU Martovetsky, N Manahan, R Moller, J Zbasnik, J AF Martovetsky, N Manahan, R Moller, J Zbasnik, J TI LLNL superconducting magnets test facility SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 16th International Conference on Magnet Technology CY SEP 26-OCT 02, 1999 CL NATL HIGH MAGNET FIELD LAB, PONTE VEDRA BEACH, FLORIDA SP Natl High Magnet Field Lab, Natl Sci Fdn, State Florida, Brookhaven Natl Lab, BWX Technol Inc, Florida State Univ, Off Res, IEEE, Council Superconductiv, Magnex Sci Ltd, Oxford Instruments, Res Instruments Div, Princeton Plasma Phys Lab, NHMFL, Los Almos Natl Lab, Pulsed Field Facil, USN, Res Off, US DOE, Div High Energy Phys, US DOE, Superconductiv Program Elect Power, Vacuumschmeleze GmbH HO NATL HIGH MAGNET FIELD LAB DE facility; superconducting magnet; CIC conductors; testing AB The FENIX facility at Lawrence Livermore National Laboratory was upgraded and refurbished in 1996-1998 for testing CICC superconducting magnets. The FENIX facility was used for superconducting high current, short sample tests for fusion programs in the late 1980-s-early 1990-s. The new facility includes a 4-m diameter vacuum vessel, two refrigerators, a 40 kA, 42 V computer controlled power supply, a new switchyard with a dump resistor, a new helium distribution valve box, several sets of power leads, data acquisition system and other auxiliary systems, which provide a lot of flexibility in testing of a wide variety of superconducting magnets in a wide range of parameters. The detailed parameters and capabilities of this test facility and its systems are described in the paper. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Martovetsky, N (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 2 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2000 VL 10 IS 1 BP 1546 EP 1548 DI 10.1109/77.828537 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 295DD UT WOS:000085950700368 ER PT J AU Zhang, L Lester, LF Baca, AG Shul, RJ Chang, PC Willison, CG Mishra, UK Denbaars, SP Zolper, JC AF Zhang, L Lester, LF Baca, AG Shul, RJ Chang, PC Willison, CG Mishra, UK Denbaars, SP Zolper, JC TI Epitaxially-grown GaN junction field effect transistors SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article DE current collapse; GaN; JFET; Mott-Gurney law; transconductance; velocity saturation ID P-N-JUNCTIONS; HIGH-TEMPERATURE; ALGAN/GAN HEMTS; GALLIUM NITRIDE; PERFORMANCE; MODFETS; BREAKDOWN; DEVICES AB Junction field effect transistors (JFET's) are fabricated on a GaN epitaxial structure grown by metal organic chemical raper deposition (MOCVD), The de and microwave characteristics of the device are presented. A junction breakdown voltage of 56 V is obtained corresponding to the theoretical limit of the breakdown field in GaN for the doping levels used, A maximum extrinsic transconductance (g(m)) of 48 mS/mm and a maximum source-drain current of 270 mA/mm are achieved on a 0.8 mu m gate JFET device at V-GS = 1 V and V-DS = 15 V. The intrinsic transconductance, calculated from the measured g(m) and the source series resistance, is 81 mS/mm, The f(T) and f(max) for these devices are 6 GHz and 12 GHz, respectively. These JFET's exhibit a significant current reduction after a high drain bias is applied, which is attributed to a partially depleted channel caused by trapped hot-electrons in the semi-insulating GaN buffer layer. A theoretical model describing the current collapse is presented, and an estimate for the length of the trapped electron region is given. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM USA. Univ Calif Santa Barbara, Dept Elect & Comp Engn, Santa Barbara, CA 93106 USA. Off Naval Res, Arlington, VA 22217 USA. RP Zhang, L (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 25 TC 26 Z9 28 U1 0 U2 10 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD MAR PY 2000 VL 47 IS 3 BP 507 EP 511 DI 10.1109/16.824716 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 291YA UT WOS:000085766300003 ER PT J AU Kirkland, MW Carlos, R Shao, XM DeHaven, XV Jacobson, AR AF Kirkland, MW Carlos, R Shao, XM DeHaven, XV Jacobson, AR TI The Los Alamos microwave interferometer SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article ID SIMPLE BIOSPHERE MODEL; CIRCULATION AB We describe a multi-antenna microwave receiver system that monitors an unmodulated beacon transmission from a geosynchronous satellite. The system interferometrically measures temporal fluctuations in tropospheric differential path length, which include fluctuations in precipitable water vapor, over 100-to 400-meter baseline lengths. Over 300 s, the system root mean square error (rms) noise is 0.01 radian. These observations will facilitate studies of air parcel motion as the means by which the causative, phase-corrupting atmospheric inhomogeneities drift over the array. The resulting data will be useful for studies of convective boundary layer turbulence, a region difficult to fully access. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kirkland, MW (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. OI Kirkland, Matt/0000-0002-1217-8864 NR 13 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAR PY 2000 VL 38 IS 2 BP 849 EP 857 DI 10.1109/36.842013 PN 1 PG 9 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 304TF UT WOS:000086499700022 ER PT J AU Tolbert, LM Peng, FZ Habetler, TG AF Tolbert, LM Peng, FZ Habetler, TG TI A multilevel converter-based universal power conditioner SO IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS LA English DT Article; Proceedings Paper CT 1999 Industry-Applications-Society Annual Meeting CY OCT 03-07, 1999 CL PHOENIX, ARIZONA DE active power filter; multilevel converter; multilevel inverter; multilevel pulsewidth modulation; series-parallel filter; universal power conditioner ID ACTIVE-FILTERS; SYSTEMS AB This paper presents the development of a control scheme for a multilevel diode-clamped converter connected in a series-parallel fashion to the electrical system such that it can compensate for deviations in utility voltage (sag, surge, and unbalance) and act as a harmonic and/or reactive current source for a load. New carrier-based multilevel pulsewidth modulation techniques are identified to maximize switch utilization of the two back-to-back diode-clamped inverters that constitute the universal power conditioner. An experimental verification for a six-level power conditioner is given. C1 Univ Tennessee, Dept Elect & Comp Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Georgia Inst Technol, Sch Elect & Comp Engn, Atlanta, GA 30332 USA. RP Tolbert, LM (reprint author), Univ Tennessee, Dept Elect & Comp Engn, Knoxville, TN 37996 USA. OI Tolbert, Leon/0000-0002-7285-609X NR 15 TC 68 Z9 73 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-9994 J9 IEEE T IND APPL JI IEEE Trans. Ind. Appl. PD MAR-APR PY 2000 VL 36 IS 2 BP 596 EP 603 DI 10.1109/28.833778 PG 8 WC Engineering, Multidisciplinary; Engineering, Electrical & Electronic SC Engineering GA 304WL UT WOS:000086507000020 ER PT J AU Critchlow, T Fidelis, K Ganesh, M Musick, R Slezak, T AF Critchlow, T Fidelis, K Ganesh, M Musick, R Slezak, T TI DataFoundry: Information management for scientific data SO IEEE TRANSACTIONS ON INFORMATION TECHNOLOGY IN BIOMEDICINE LA English DT Article DE databases; data warehouses; informatics; integration; meta-data ID SEQUENCE AB Data warehouses and data marts have been successfully applied to a multitude of commercial business applications. They have proven to be invaluable tools by integrating information from distributed, heterogeneous sources and summarizing this data for use throughout the enterprise. Although the need for information dissemination is as vital in science as in business, working warehouses in this community are scarce because traditional warehousing techniques do not transfer to scientific environments. There are two primary reasons for this difficulty, First, schema integration is more difficult for scientific databases than for business sources, because of the complexity of the concepts and the associated relationships. While this difference has not yet been fully explored, it is an important consideration when determining how to integrate autonomous sources. Second, scientific data sources have highly dynamic data representations (schemata), When a data source participating in a warehouse changes its schema, both the mediator transferring data to the warehouse and the warehouse itself need to be updated to reflect these modifications. The cost of repeatedly performing these updates in a traditional warehouse, as is required in a dynamic environment, is prohibitive. This paper discusses these issues within the context of the DataFoundry project, an ongoing research effort at Lawrence Livermore National Laboratory. DataFoundry utilizes a unique integration strategy to identify corresponding instances while maintaining differences between data from different sources, and a novel architecture and an extensive meta-data infrastructure, which reduce the cost of maintaining a warehouse. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. RP Critchlow, T (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. NR 15 TC 23 Z9 26 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1089-7771 J9 IEEE T INF TECHNOL B JI IEEE T. Inf. Technol. Biomed. PD MAR PY 2000 VL 4 IS 1 BP 52 EP 57 DI 10.1109/4233.826859 PG 6 WC Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Mathematical & Computational Biology; Medical Informatics SC Computer Science; Mathematical & Computational Biology; Medical Informatics GA 316NE UT WOS:000087173000007 PM 10761774 ER PT J AU Chamberlain, BL Choi, SE Lewis, EC Lin, C Snyder, L Weathersby, WD AF Chamberlain, BL Choi, SE Lewis, EC Lin, C Snyder, L Weathersby, WD TI ZPL: A machine independent programming language for parallel computers SO IEEE TRANSACTIONS ON SOFTWARE ENGINEERING LA English DT Article DE portable; efficient; parallel programming language ID COMPUTATION; MODELS AB The goal of producing architecture-independent parallel programs is complicated by the competing need for high performance. The ZPL programming language achieves both goals by building upon an abstract parallel machine and by providing programming constructs that allow the programmer to "see" this underlying machine. This paper describes ZPL and provides a comprehensive evaluation of the language with respect to its goals of performance, portability, and programming convenience. In particular, we describe ZPL's machine-independent performance model, describe the programming benefits of ZPL's region-based constructs, summarize the compilation benefits of the language's high-level semantics, and summarize empirical evidence that ZPL has achieved both high performance and portability on diverse machines such as the IBM SP-2, Gray T3E, and SGI Power Challenge. C1 Univ Washington, Dept Comp Sci & Engn, Seattle, WA 98195 USA. Los Alamos Natl Lab, Adv Comp Lab, Los Alamos, NM 87545 USA. Univ Texas, Dept Comp Sci, Austin, TX 78712 USA. Metris Co, Champaign, IL 61820 USA. RP Chamberlain, BL (reprint author), Univ Washington, Dept Comp Sci & Engn, Seattle, WA 98195 USA. EM sungeun@lanl.gov; lin@cs.utexas.edu; snyderj@cs.washington.edu; derrick.weathersby@metriscompanies.com NR 52 TC 26 Z9 26 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0098-5589 J9 IEEE T SOFTWARE ENG JI IEEE Trans. Softw. Eng. PD MAR PY 2000 VL 26 IS 3 BP 197 EP 211 DI 10.1109/32.842947 PG 15 WC Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 313ZY UT WOS:000087030700002 ER PT J AU Hines, CJ Milton, DK Larsson, L Petersen, MR Fisk, WJ Mendell, MJ AF Hines, CJ Milton, DK Larsson, L Petersen, MR Fisk, WJ Mendell, MJ TI Characterization and variability of endotoxin and 3-hydroxy fatty acids in an office building during a particle intervention study SO INDOOR AIR LA English DT Article DE endotoxion; 3-hydroxy fatty acids; indoor air; exposure assessment ID CHROMATOGRAPHY MASS-SPECTROMETRY; ENVIRONMENTAL ENDOTOXIN; HOUSE-DUST; LIMULUS ASSAY; EXPOSURES; SEVERITY; ASTHMA; LEAD AB Air and dust samples were collected on two floors of an office building during a double-blind particle intervention study to examine spatial and temporal variability of airborne endotoxin over a period of weeks, and to characterize endotoxin activity and lipopolysaccharide (LPS) content in carpet and chair dust. Air samples were collected on multiple days within and across weeks. Dust samples were collected from carpets and chairs one day per week for three weeks. Endotoxin was measured using a Limulus assay. Dust samples were analyzed for LPS by determination of 3-hydroxy fatty acids (3-OHFAs) using gas chromatography-mass spectrometry. The geometric mean (geometric standard deviation) for 96 indoor air samples was 0.24 (1.6) EU/m(3). Significant within-floor spatial variation of airborne endotoxin was found (P<0.0001, n=80). Temporal variability of airborne endotoxin was not significant across weeks. Mean (+/-SD) endotoxin levels in carpet dust (59+/-9.3 EU/mg dust, n=12) and in chair dust (38+/-7.7 EU/mg dust, n=10) were significantly different (P<0.001). Carbon chain length-dependent differences in 3-OHFA levels by dust source and floor were found. Enhanced air filtration did not significantly affect airborne endotoxin (P=0.62); however, total dust mass and total endotoxin in carpet dust samples increased significantly after enhanced surface cleaning (P<0.01). These findings suggest that spatial variability, dust source, and surface cleaning may influence building occupant exposures to endotoxin. C1 NIOSH, Cincinnati, OH 45226 USA. Harvard Univ, Sch Publ Hlth, Boston, MA 02115 USA. Lund Univ, Dept Med Microbiol, Lund, Sweden. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Hines, CJ (reprint author), NIOSH, 4676 Columbia Pkwy,R-14, Cincinnati, OH 45226 USA. EM cjh8@cdc.gov RI Milton, Donald/G-3286-2010 OI Milton, Donald/0000-0002-0550-7834 NR 27 TC 27 Z9 27 U1 2 U2 4 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0905-6947 J9 INDOOR AIR JI Indoor Air PD MAR PY 2000 VL 10 IS 1 BP 2 EP 12 DI 10.1034/j.1600-0668.2000.010001002.x PG 11 WC Construction & Building Technology; Engineering, Environmental; Public, Environmental & Occupational Health SC Construction & Building Technology; Engineering; Public, Environmental & Occupational Health GA 299VU UT WOS:000086219200001 PM 10842455 ER PT J AU Litvak, A Gadgil, AJ Fisk, WJ AF Litvak, A Gadgil, AJ Fisk, WJ TI Hygroscopic fine mode particle deposition on electronic circuits and resulting degradation of circuit performance: An experimental study SO INDOOR AIR-INTERNATIONAL JOURNAL OF INDOOR AIR QUALITY AND CLIMATE LA English DT Article DE electronics; experiments; deposition; failures; indoor air; particles ID INDOOR AIR-QUALITY AB A portion of electronic equipment failures is a consequence of particle deposition on electronic circuits in normal indoor environments. Deposited hygroscopic particles reduce the electrical isolation (EI) between conductors. In laboratory experiments, we investigated the mechanisms, locations, and effects of particle deposition on electronic circuits with surface mounted chips (SMCs) and also on small television sets. One set of electronics was exposed for 281 h to an unusually high concentration of artificially-generated ammonium sulfate particles while a second set (experimental controls) was exposed to normal indoor particles. The particle mass concentration in the high-exposure chamber was 500 times higher than normal. Television reliability was observed and the changes in EI between adjacent legs of SMCs were measured. The experiments demonstrate the strong influence of electrostatic forces on the locations and rates of particle deposition. Although televisions did not fail after exposure to concentrated aerosols, the EI between adjacent legs of the SMCs was, in many cases, greatly diminished. Relative humidity had a very strong influence on the magnitude of EI. A qualitative explanation of the mechanisms of particle deposition and circuit degradation is proposed, including the role of fibers. Finally, a potential method to reduce particle deposition on electronic components is discussed. C1 ENTPE, Lab Sci Habitat, DGCB, CNRS,URA 1652, F-69518 Vaulx En Velin Dedex, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Indoor Environm Dept, Berkeley, CA 94720 USA. RP Litvak, A (reprint author), CETE Lyon, DVT HTC, 46 Rue St ThEobald,BP 128, F-38081 Lilsle Diabeau, France. NR 8 TC 15 Z9 16 U1 0 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0905-6947 J9 INDOOR AIR JI Indoor Air-Int. J. Indoor Air Qual. Clim. PD MAR PY 2000 VL 10 IS 1 BP 47 EP 56 PG 10 WC Construction & Building Technology; Engineering, Environmental; Public, Environmental & Occupational Health SC Construction & Building Technology; Engineering; Public, Environmental & Occupational Health GA 299VU UT WOS:000086219200006 PM 10842460 ER PT J AU Macek, RW Duffey, TA AF Macek, RW Duffey, TA TI Finite cavity expansion method for near-surface effects and layering during Earth penetration SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article DE earth penetrator; oblique impact; cavity expansion; Mohr-Coulomb ID TARGETS AB A finite spherical cavity expansion technique is developed to simulate the loading on projectiles penetrating geologic media, Damaged Mohr-Coulomb plasticity models and a general pressure-dependent damaged plasticity model are used with incompressible kinematics to approximate a wide range of targets. The finite cavity expansion approximation together with directional sampling reasonably captures near-surface and layering effects without resort to ad hoc or empirical correction factors. The Mohr-Coulomb models are integrated exactly to provide a very efficient loading algorithm for use with conventional implicit or explicit finite element structural analysis, The more general constitutive model requires numerical integration and leads to a more computationally intensive procedure. However, subcycling is easily implemented with the numerical integration and thus an efficient loading method is readily achieved even for large complex simulations using explicit finite element analysis. The utility of the finite cavity expansion approach is demonstrated by comparison of simulations to measured test data from projectiles penetrating rock and soil targets. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Grp ESA EA MS P946, Los Alamos, NM 87545 USA. RP Duffey, TA (reprint author), POB 1239, Tijeras, NM 87059 USA. NR 16 TC 12 Z9 18 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD MAR PY 2000 VL 24 IS 3 BP 239 EP 258 DI 10.1016/S0734-743X(99)00156-6 PG 20 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 284AX UT WOS:000085309500003 ER PT J AU Tsap, LV Goldgof, DB Sarkar, S Powers, PS AF Tsap, LV Goldgof, DB Sarkar, S Powers, PS TI A method for increasing precision and reliability of elasticity analysis in complicated burn scar cases SO INTERNATIONAL JOURNAL OF PATTERN RECOGNITION AND ARTIFICIAL INTELLIGENCE LA English DT Article DE physically-based vision; deformable models; nonrigid motion analysis; active contours; biomedical applications; iterative descent search; finite element analysis ID DEFORMATIONS; CONTOURS; TRACKING; MODEL AB In this paper we propose a method for increasing precision and reliability of elasticity analysis in complicated burn scar cases. The need for a technique that would help physicians by objectively assessing elastic properties of scars, motivated our original algorithm. This algorithm successfully employed active contours for tracking and finite element models for strain analysis. However, the previous approach considered only one normal area and one abnormal area within the region of interest, and scar shapes which were somewhat simplified. Most burn scars have rather complicated shapes and may include multiple regions with different elastic properties. Hence, we need a method capable of adequately addressing these characteristics. The new method can split the region into more than two localities with different material properties, select and quantify abnormal areas, and apply different forces if it is necessary for a better shape description of the scar. The method also demonstrates the application of scale and mesh refinement techniques in this important domain. It is accomplished by increasing the number of Finite Element Method (FEM) areas as well as the number of elements within the area. The method is successfully applied to elastic materials and real burn scar cases. We demonstrate all of the proposed techniques and investigate the behavior of elasticity function in a 3-D space. Recovered properties of elastic materials are compared with those obtained by a conventional mechanics-based approach. Scar ratings achieved with the method are correlated against the judgments of physicians. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. Univ S Florida, Dept Comp Sci & Engn, Tampa, FL 33620 USA. Univ S Florida, Dept Psychiat, Tampa Bay Reg Burn Ctr, Tampa, FL 33620 USA. RP Tsap, LV (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, POB 5508, Livermore, CA 94551 USA. RI Sarkar, Sudeep/A-8213-2009 OI Sarkar, Sudeep/0000-0001-7332-4207 NR 32 TC 2 Z9 2 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-0014 J9 INT J PATTERN RECOGN JI Int. J. Pattern Recognit. Artif. Intell. PD MAR PY 2000 VL 14 IS 2 BP 189 EP 210 DI 10.1142/S0218001400000131 PG 22 WC Computer Science, Artificial Intelligence SC Computer Science GA 312QX UT WOS:000086955100005 ER PT J AU Rubin, MB Vorobiev, OY Glenn, LA AF Rubin, MB Vorobiev, OY Glenn, LA TI Mechanical and numerical modeling of a porous elastic-viscoplastic material with tensile failure SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article DE failure; finite deformation; plasticity; porous media; viscoplastic ID LARGE DEFORMATION; METALS; THERMODYNAMICS; PLASTICITY; MEDIA AB The objective of this paper is to develop simple but comprehensive constitutive equations that model a number of physical phenomena exhibited by dry porous geological materials and metals. For geological materials the equations model: porous compaction; porous dilation due to distortional deformation and tensile failure; shear enhanced compaction; pressure hardening of the yield strength; damage of the yield strength due to distortional deformation and porosity changes; and dependence of the yield strength on the Lode angle. For metals the equations model: hardening of the yield strength due to plastic deformation; pressure and temperature dependence of the yield strength, and damage due to nucleation of porosity during tensile failure. The equations are valid for large deformations and the elastic response is hyperelastic in the sense that the stress is related to a derivative of the Helmholtz free energy. Also, the equations are viscoplastic with rate dependence occurring in both the evolution equations of porosity and elastic distortional deformations. Moreover, formulas are presented for robust numerical integration of the evolution equations at the element level that can be easily implemented into standard computer programs for dynamic response of materials. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Technion Israel Inst Technol, Fac Mech Engn, IL-32000 Haifa, Israel. Univ Calif Lawrence Livermore Natl Lab, Geophys & Global Secur Div, Livermore, CA 94550 USA. RP Rubin, MB (reprint author), Technion Israel Inst Technol, Fac Mech Engn, IL-32000 Haifa, Israel. NR 36 TC 34 Z9 43 U1 2 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0020-7683 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD MAR PY 2000 VL 37 IS 13 BP 1841 EP 1871 DI 10.1016/S0020-7683(98)00333-3 PG 31 WC Mechanics SC Mechanics GA 277LL UT WOS:000084935000003 ER PT J AU Takai, K Sugai, A Itoh, T Horikoshi, K AF Takai, K Sugai, A Itoh, T Horikoshi, K TI Palaeococcus ferrophilus gen. nov., sp nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney SO INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY LA English DT Article DE hyperthermophilic archaeon; barophilic; Thermococcales; deep-sea hydrothermal vent ID PYROCOCCUS-FURIOSUS; ARCHAEBACTERIA; REPRESENTS; SULFUR; 110-DEGREES-C; REDUCTION; LIFE; IRON; BACTERIUM; FE(III) AB A novel barophilic, hyperthermophilic archaeon was isolated from a deep-sea hydrothermal vent chimney at the Myojin Knell in the Ogasawara-Bonin Are. Japan. The cells were found to be irregular cocci and motile with multiple polar flagella. Growth was observed between 60 and 88 degrees C (opt, 83 OC; 30 min doubling time), ph 4.0 and 8.0 (opt, ph 6.0). 20 and 73 g sea salts l(-1) (opt, 47 g l(-1)) and 0.1 and 60 MPa (opt, 30 MPa). The isolate was a strictly anaerobic chemoorganotroph capable of utilizing proteinaceous substrates such as yeast extract, peptone, tryptone and casein in the presence of elemental sulfur or ferrous iron. The G+C content of the genomic DNA was 53.5 mol%. Phylogenetic analysis based on 16S rDNA sequences indicated that the isolate was a member of an ancient lineage of the Thermococcales that diverged prior to the formation of the two genera Thermococcus and Pyrococcus, On the basis of the physiological and molecular properties of the new isolate, the name Palaeococcus ferrophilus gen, nov., sp. nov. is proposed. The type strain is strain DMJ(T) (= JCM 10246(T)). C1 JAMSTEC, DEEP STAR, Yokosuka, Kanagawa 2370061, Japan. Kitasato Univ, Ctr Nat Sci, Div Chem, Sagamihara, Kanagawa 2288555, Japan. RP Takai, K (reprint author), Pacific NW Lab, POB 999,Mailstop P7-50, Richland, WA 99352 USA. EM ken.takai@pnl.gov NR 58 TC 103 Z9 110 U1 2 U2 13 PU SOC GENERAL MICROBIOLOGY PI READING PA MARLBOROUGH HOUSE, BASINGSTOKE RD, SPENCERS WOODS, READING RG7 1AG, BERKS, ENGLAND SN 1466-5026 J9 INT J SYST EVOL MICR JI Int. J. Syst. Evol. Microbiol. PD MAR PY 2000 VL 50 BP 489 EP 500 PN 2 PG 12 WC Microbiology SC Microbiology GA 298LX UT WOS:000086141800006 PM 10758851 ER PT J AU Rademaker, JLW Hoste, B Louws, FJ Kersters, K Swings, J Vauterin, L Vauterin, P de Bruijn, FJ AF Rademaker, JLW Hoste, B Louws, FJ Kersters, K Swings, J Vauterin, L Vauterin, P de Bruijn, FJ TI Comparison of AFLP and rep-PCR genomic fingerprinting with DNA-DNA homology studies: Xanthomonas as a model system SO INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY LA English DT Article DE rep-PCR; AFLP; Xanthomonas; DNA-DNA homology studies; molecular phylogeny ID FRAGMENT-LENGTH-POLYMORPHISM; POLYMERASE CHAIN-REACTION; AD-HOC-COMMITTEE; BACTERIAL SYSTEMATICS; RESTRICTION ANALYSIS; GENUS AEROMONAS; SEQUENCES; IDENTIFICATION; DIVERSITY; TAXONOMY AB The genus Xanthomonas contains a large number of strains, which have been characterized by a variety of phenotypic and genotypic classification methods. The Xanthomonas collection constitutes one of the largest groups of bacteria that have been characterized phylogenetically by DNA-DNA homology studies and genomic fingerprinting. Presently, a total genomic DNA-DNA homology value of 70% represents an internationally accepted criterion to define bacterial species levels. However, the complexity of DNA-DNA reassociation kinetics methods precludes the rapid analysis of large numbers of bacterial isolates, which is imperative for molecular microbial diversity studies. Therefore, the aim of this study was to compare more facile PCR-based genomic fingerprinting techniques, such as repetitive-sequence-based (rep)PCR and AFLP genomic fingerprinting, to DNA-DNA hybridization studies. Using three different primer sets, rep-PCR genomic fingerprint patterns were generated for 178 Xanthomonas strains, belonging to all 20 previously defined DNA-DNA homology groups, and one Stenotrophomonas maltophilia strain. In addition, AFLP genomic fingerprints were produced for a subset of 80 Xanthomonas strains belonging to the 20 DNA-DNA homology groups and for the S. maltophilia strain. Similarity values derived from rep-PCR- and AFLP-generated fingerprinting analyses were calculated and used to determine the correlation between rep-PCR- or AFLP-derived relationships and DNA-DNA homology values. A high correlation was observed, suggesting that genomic fingerprinting techniques truly reveal genotypic and phylogenetic relationships of organisms. On the basis of these studies, we propose that genomic fingerprinting techniques such as rep-PCR and AFLP can be used as rapid, highly discriminatory screening techniques to determine the taxonomic diversity and phylogenetic structure of bacterial populations. C1 Michigan State Univ, US DOE, Plant Res Lab, Dept Microbiol, E Lansing, MI 48824 USA. Michigan State Univ, NSF, Ctr Microbial Ecol, E Lansing, MI 48824 USA. N Carolina State Univ, Dept Plant Pathol, Raleigh, NC 27695 USA. Rijksuniv Gent, BCCM LMG Bacteria Collect, B-9000 Ghent, Belgium. Rijksuniv Gent, Microbiol Lab, B-9000 Ghent, Belgium. Appl Maths BVBA, B-9051 Ghent, Belgium. RP de Bruijn, FJ (reprint author), Michigan State Univ, US DOE, Plant Res Lab, Dept Microbiol, E Lansing, MI 48824 USA. NR 47 TC 232 Z9 258 U1 0 U2 17 PU SOC GENERAL MICROBIOLOGY PI READING PA MARLBOROUGH HOUSE, BASINGSTOKE RD, SPENCERS WOODS, READING RG7 1AE, BERKS, ENGLAND SN 1466-5026 J9 INT J SYST EVOL MICR JI Int. J. Syst. Evol. Microbiol. PD MAR PY 2000 VL 50 BP 665 EP 677 PN 2 PG 13 WC Microbiology SC Microbiology GA 298LX UT WOS:000086141800029 PM 10758874 ER PT J AU Mehlhorn, TA Desjarlais, M Haill, TA Lash, JS Rosenthal, SE Slutz, SA Stoltz, PH Vesey, RA Oliver, B AF Mehlhorn, TA Desjarlais, M Haill, TA Lash, JS Rosenthal, SE Slutz, SA Stoltz, PH Vesey, RA Oliver, B TI The role of strong coupling in z-pinch-driven approaches to high yield inertial confinement fusion SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT International Conference on Strongly Coupled Coulomb Systems CY SEP 04-10, 1999 CL ST MALO, FRANCE SP European Sci Fdn, CEA DAM, CNRS, Direct Gen Armement, European Res Off, Univ Paris Sud ID DENSE-PLASMA; CONDUCTIVITY AB Peak x-ray powers as high as 280+/-40 TW have been generated from the implosion of tungsten wire arrays on the Z Accelerator at Sandia National Laboratories. The high x-ray powers radiated by these z-pinches provide an attractive new driver option for high yield inertial confinement fusion (ICF). The high x-ray powers appear to be a result of using a large number of wires in the array which decreases the perturbation seed to the magnetic Rayleigh-Taylor (MRT) instability and diminishes other 3-D effects. Simulations to confirm this hypothesis require a 3-D MHD code capability, and associated databases, to follow the evolution of the wires from cold solid through melt vaporization, ionization, and finally to dense imploded plasma Strong coupling plays a role in this process, the importance of which depends on the wire material and the current time history of the pulsed power driver. Strong coupling regimes are involved in the plasmas in the convolute and transmission line of the powerflow system. Strong coupling can also play a role in the physics of the z-pinch-driven high yield ICF target Finally, strong coupling can occur in certain z-pinch-driven application experiments. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Mission Res Corp, Albuquerque, NM 87106 USA. RP Mehlhorn, TA (reprint author), Sandia Natl Labs, POB 5800,MS-1186, Albuquerque, NM 87185 USA. NR 13 TC 3 Z9 3 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD MAR PY 2000 VL 10 IS P5 BP 65 EP 72 DI 10.1051/jp4:2000508 PG 8 WC Physics, Multidisciplinary SC Physics GA 313YB UT WOS:000087026300009 ER PT J AU Emery, VJ Kivelson, SA AF Emery, VJ Kivelson, SA TI Are there stripes in the ET materials? SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 20th Anniversary of Organic Superconductivity CY DEC 07, 1999 CL ORSAY, FRANCE SP CNRS ID T-J MODEL; MUON SPIN ROTATION; PHASE-SEPARATION; NORMAL-STATE; SUPERCONDUCTING LA1.85SR0.15CUO4; TEMPERATURE SUPERCONDUCTORS; TRANSITION TEMPERATURE; C SUPERCONDUCTORS; GAP ANISOTROPY; FERMI-SURFACE AB We propose that a central aspect of two-dimensional doped antiferromagnets, including the cuprate high temperature superconductors and the (BEDT-TTF)(2)X materials, is a "dynamical dimension reduction" in which the electrons self-organise in a quasi one-dimensional manner. Strong repulsive interactions between electrons frustrate their motion, resulting in a large zero-point kinetic energy. As a function of decreasing temperature, tills kinetic energy is lowered in three steps that are reflected in a sequence of crossovers and phase transitions: first of all, the system develops a charge-inhomogeneous state an array of one-dimensional metallic stripes that forms an electronic liquid crystal! this lowers the kinetic energy along a stripe. In the transverse direction in the planes, the kinetic energy is lowered by pair hopping, which first creates spin pairs and then, at a lower temperature, superconducting phase coherence. This constitutes a new mechanism and many-body theory of superconductivity. Evidence for this behaviour in the high temperature superconductors, and implications of the conjecture that similar behaviour occurs in the (BEDT-TTF)(2)X materials are described. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. RP Emery, VJ (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 78 TC 1 Z9 1 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD MAR PY 2000 VL 10 IS P3 BP 127 EP 137 DI 10.1051/jp4:2000313 PG 11 WC Physics, Multidisciplinary SC Physics GA 302QM UT WOS:000086376700013 ER PT J AU Kraeft, WD Schlanges, M Riemann, J DeWitt, HE AF Kraeft, WD Schlanges, M Riemann, J DeWitt, HE TI Single and two particle properties and EOS of dense plasmas SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT International Conference on Strongly Coupled Coulomb Systems CY SEP 04-10, 1999 CL ST MALO, FRANCE SP European Sci Fdn, CEA DAM, CNRS, Direct Gen Armement, European Res Off, Univ Paris Sud ID DEPENDENT GROUND-STATE; STELLAR INTERIORS; ENERGY-SPECTRUM; EQUATION AB It is shown how single and two particle properties enter the equation of state of dense plasmas. Results are given for weakly nonideal plasmas which are of interest for helioseismology and inertial fusion. C1 Univ Greifswald, Inst Phys, D-17487 Greifswald, Germany. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Kraeft, WD (reprint author), Univ Greifswald, Inst Phys, Domstr 10A, D-17487 Greifswald, Germany. NR 10 TC 1 Z9 1 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD MAR PY 2000 VL 10 IS P5 BP 167 EP 170 DI 10.1051/jp4:2000525 PG 4 WC Physics, Multidisciplinary SC Physics GA 313YB UT WOS:000087026300026 ER PT J AU Sanbonmatsu, KY Thode, LE Vu, HX Murillo, MS AF Sanbonmatsu, KY Thode, LE Vu, HX Murillo, MS TI Comparison of molecular dynamics and particle-in-cell simulations for strongly coupled plasmas SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT International Conference on Strongly Coupled Coulomb Systems CY SEP 04-10, 1999 CL ST MALO, FRANCE SP European Sci Fdn, CEA DAM, CNRS, Direct Gen Armement, European Res Off, Univ Paris Sud AB A quantitative comparison between molecular dynamics and particle-in-cell simulations for strongly coupled plasmas is performed. While the particle-in-cell simulation's nonlinear potential solver produces a significant improvement in accuracy over molecular dynamics, the requirement for many grid cells between particles (in the strongly coupled regime) causes the particle-in-cell simulation to be prohibitively expensive. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sanbonmatsu, KY (reprint author), Univ Calif Los Alamos Natl Lab, MS B259, Los Alamos, NM 87545 USA. NR 4 TC 3 Z9 3 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD MAR PY 2000 VL 10 IS P5 BP 259 EP 262 DI 10.1051/jp4:2000546 PG 4 WC Physics, Multidisciplinary SC Physics GA 313YB UT WOS:000087026300047 ER PT J AU Ross, M Yang, LH Galli, G AF Ross, M Yang, LH Galli, G TI Equation of state of shock compressed liquid deuterium SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT International Conference on Strongly Coupled Coulomb Systems CY SEP 04-10, 1999 CL ST MALO, FRANCE SP European Sci Fdn, CEA DAM, CNRS, Direct Gen Armement, European Res Off, Univ Paris Sud ID STATISTICAL-MECHANICS; HYDROGEN; DISSOCIATION; PRESSURE AB Shock compression experiments carried out at Livermore using liquid deuterium have measured the Hugoniot and shock temperature to pressures up to 3.2 Mbar. In the region between 4000 K to 10,000 K the prediction of small or negative values of (dP/dT)(V) suggests that the molecular fluid dissociates into a mixture containing a significant fraction of string-like matter. In the temperature range from 20,000 to 50,000 K the fluid may be treated as a nearly degenerate liquid metal. Above 50,000 K electronic excitation becomes significant and the fluid must be treated as a a dense plasma. There appears to be no experimental evidence in favor of a first order phase transition in the fluid. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Ross, M (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 20 TC 1 Z9 1 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD MAR PY 2000 VL 10 IS P5 BP 281 EP 286 DI 10.1051/jp4:2000551 PG 6 WC Physics, Multidisciplinary SC Physics GA 313YB UT WOS:000087026300052 ER PT J AU Militzer, B Pollock, EL AF Militzer, B Pollock, EL TI Introduction to the variational density matrix method and its application to dense hydrogen SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT International Conference on Strongly Coupled Coulomb Systems CY SEP 04-10, 1999 CL ST MALO, FRANCE SP European Sci Fdn, CEA DAM, CNRS, Direct Gen Armement, European Res Off, Univ Paris Sud ID MOLECULAR-DYNAMICS AB A new variational principle for optimizing thermal density matrices is introduced. As a first application, the variational many body density matrix is written as a determinant of one body density matrices which are approximated by Gaussians with the mean, width and amplitude as variational parameters. This variational density matrix is used to calculate properties of the hot, dense hydrogen. First results for a density of r(s) = 2 are presented. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Calif Lawrence Livermore Natl Lab, Dept Phys, Livermore, CA 94550 USA. RP Militzer, B (reprint author), Univ Illinois, Dept Phys, 1110 W Green St, Urbana, IL 61801 USA. NR 7 TC 0 Z9 0 U1 1 U2 3 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD MAR PY 2000 VL 10 IS P5 BP 315 EP 318 DI 10.1051/jp4:2000559 PG 4 WC Physics, Multidisciplinary SC Physics GA 313YB UT WOS:000087026300060 ER PT J AU Kalman, GJ Rosenberg, M deWitt, H AF Kalman, GJ Rosenberg, M deWitt, H TI Static and dynamic properties of Yukawa systems: Application to dusty plasmas SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT International Conference on Strongly Coupled Coulomb Systems CY SEP 04-10, 1999 CL ST MALO, FRANCE SP European Sci Fdn, CEA DAM, CNRS, Direct Gen Armement, European Res Off, Univ Paris Sud ID COUPLED COULOMB LIQUIDS; 2-DIMENSIONAL ELECTRON LIQUID; SHEAR-MODE DISPERSION; DIELECTRIC TENSOR; RESPONSE FUNCTION; LIMIT; THERMODYNAMICS AB The pair correlation function g(r) for a strongly coupled Yukawa liquid has been generated by using an HNC code for a wide range of nominal coupling (Gamma=beta Z(2)e(2)/a) and range (<(kappa)over bar> = kappa a) values (a is the interparticle distance). We have analyzed the collective mode structure of the system via the Quasi Localized Charge Approximation (QLCA) which requires the input of the correlation function [2]. The availability of g(r) has now made it possible to extend the analysis to arbitrary wave lengths for high K-values. Both mode frequencies approach the same asymptotic limit, the Einstein frequency of the localized mode. C1 Boston Coll, Dept Phys, Chestnut Hill, MA 02467 USA. Univ Calif San Diego, Dept Elect & Comp Engn, La Jolla, CA 92093 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Kalman, GJ (reprint author), Boston Coll, Dept Phys, Chestnut Hill, MA 02467 USA. NR 11 TC 8 Z9 8 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD MAR PY 2000 VL 10 IS P5 BP 403 EP 408 DI 10.1051/jp4:2000578 PG 6 WC Physics, Multidisciplinary SC Physics GA 313YB UT WOS:000087026300079 ER PT J AU Kitamura, H Murillo, MS Weisheit, JC AF Kitamura, H Murillo, MS Weisheit, JC TI Atomic excitation in strongly coupled plasmas SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT International Conference on Strongly Coupled Coulomb Systems CY SEP 04-10, 1999 CL ST MALO, FRANCE SP European Sci Fdn, CEA DAM, CNRS, Direct Gen Armement, European Res Off, Univ Paris Sud AB In dense plasmas atomic excitation rates arising from scattering between atoms and surrounding plasma particles are formulated on the basis of the equations of motion for density matrices in a stochastic potential. This model enables us to treat strong transitions for which the first-order perturbation theory does not apply. Within a decorrelation approximation, which enables one to break up the higher-order correlation functions of plasma density fluctuations into the products of binary correlation functions (i.e., dynamic structure factors), the interaction is effectively summed to infinite order. This method is applied to two-level atoms in hydrogen plasmas. It is thereby demonstrated that when the plasma density is sufficiently high, low-frequency ion-density fluctuations may cause coherent atomic excitation between close lying states. Such coherent excitation cannot be described by the conventional collisional rate equations based on the first-order perturbation theory. C1 Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. Univ Tokyo, Inst Solid State Phys, Tokyo 1068666, Japan. Rice Univ, Dept Space Phys & Astron, Houston, TX 77005 USA. RP Los Alamos Natl Lab, Div Appl Phys, POB 1663, Los Alamos, NM 87545 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD MAR PY 2000 VL 10 IS P5 BP 493 EP 496 DI 10.1051/jp4:2000595 PG 4 WC Physics, Multidisciplinary SC Physics GA 313YB UT WOS:000087026300096 ER PT J AU De Belie, N Richardson, M Braam, CR Svennerstedt, B Lenehan, JJ Sonck, B AF De Belie, N Richardson, M Braam, CR Svennerstedt, B Lenehan, JJ Sonck, B TI Durability of building materials and components in the agricultural environment: Part I, The agricultural environment and timber structures SO JOURNAL OF AGRICULTURAL ENGINEERING RESEARCH LA English DT Review ID WOOD DECAY; SILAGE EFFLUENT; SEWER PIPES; BROWN-ROT; FUNGI; PRESERVATIVES; CONCRETE; DERIVATIVES; CALIFORNIA; CORROSION AB Agricultural environments can be very aggressive to building materials and components due to the specific physical and chemical agents present. It is therefore evident from several viewpoints that the consideration of the durability of building materials and components is an important aspect of design. Economic considerations, animal welfare, pollution control and environmental aesthetics are all linked with durable design. In this review, an overview of the existing knowledge on durability of different building materials and components subject to this specific environment is given. The first part of the review focuses on the characteristics of the agricultural environment and the durability of timber structures. Different farm buildings are examined, including animal houses for cattle, pigs and poultry; slurry pits; horticultural buildings; farm roads; and silos and other storage systems for agricultural products. The susceptibility to degradation of these buildings or their components is highlighted. The use of wood in agricultural structures, its deterioration and methods for protection are dealt with. The review reveals that little has been published about timber degradation in specific agricultural environments. Laboratory tests and field trials are mostly developed to simulate decay in timber either in contact with the ground or in above-ground structures. Recent research focuses on fungal decay and attack by insects and (seldom) bacteria on different types of wood under a variety of environmental conditions (temperature, humidity, etc.). Methods to distinguish between fungi are proposed. Different measures to quantify the degree of decay are investigated. New diagnostic methods for detecting incipient wood decay in vitro and in situ are developed. New wood preservatives are being proposed continuously, including different methods to retard the leaching of boron from treated timber and the use of monomers that are polymerized in situ. Continuously, more attention is paid to the design of environmentally benign methods for preserving wood in service. (C) 2000 Silsoe Research Institute. C1 Univ Leuven, Dept Agroengn & Econ, Louvain, Belgium. Univ Coll Dublin, Dept Civil Engn, Dublin, Ireland. Delft Univ Technol, Fac Civil Engn, Concrete Struct Grp, Delft, Netherlands. Swedish Univ Agr Sci, Dept Agr Biosyst & Technol, Alnarp, Sweden. Agr & Food Dev Author, Grange Res Ctr, TEAGASC, Dunsany, Meath, Ireland. Agr Res Ctr, Dept Mechanisat Labour Bldg Anim Welf & Environm, Ghent, Belgium. RP De Belie, N (reprint author), Univ Leuven, Dept Agroengn & Econ, Louvain, Belgium. NR 97 TC 13 Z9 13 U1 2 U2 17 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0021-8634 J9 J AGR ENG RES JI J. Agr. Eng. Res. PD MAR PY 2000 VL 75 IS 3 BP 225 EP 241 DI 10.1006/jaer.1999.0505 PG 17 WC Agricultural Engineering SC Agriculture GA 297TH UT WOS:000086098400001 ER PT J AU Britt, PF AF Britt, PF TI Special issue - Fundamentals of pyrolysis - Preface SO JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS LA English DT Editorial Material ID THERMAL-CRACKING; HYDROCARBONS; ENERGIES; PROGRAM C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Phys Organ Chem Grp, Oak Ridge, TN 37831 USA. RP Britt, PF (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Phys Organ Chem Grp, Bld 4500N,D-28,MS-6197,POB 2008,1 Bethel Valley R, Oak Ridge, TN 37831 USA. NR 28 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-2370 J9 J ANAL APPL PYROL JI J. Anal. Appl. Pyrolysis PD MAR PY 2000 VL 54 IS 1-2 BP 1 EP 4 DI 10.1016/S0165-2370(99)00091-1 PG 4 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 291FA UT WOS:000085722400001 ER PT J AU Poutsma, ML AF Poutsma, ML TI Fundamental reactions of free radicals relevant to pyrolysis reactions SO JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS LA English DT Article DE free radicals; pyrolysis reactions; homolysis ID ATOM-TRANSFER-REACTIONS; BOND-DISSOCIATION ENERGIES; CARBON-CARBON BOND; STABILIZATION ENERGIES; HYDROGEN-ATOM; PHENYL ETHER; GAS-PHASE; RESONANCE STABILIZATION; THERMAL-DECOMPOSITION; HYDROCARBON RADICALS AB Free-radical mechanisms are ubiquitous for pyrolysis of organic substrates. Background information is supplied to assist in the interpretation of such reactions by dissection into the elementary radical-forming, radical-consuming, and radical-interconverting reactions that form the building blocks of overall mechanisms. Particular attention is given to homolysis, hydrogen abstraction, beta-scission-addition, and rearrangement steps, and to bond-breaking and bond-forming processes. Since the thermochemistry of such elementary reactions is dependent on the stability of the radicals involved, the major influences of structural changes on radical stability are reviewed. Kinetics of prototypical elementary reactions and their responses to structural changes are rationalized in terms of their Arrhenius parameters. The fundamental relationships between thermochemical parameters and kinetic parameters are summarized, and the use of these to estimate rate constants for cases where data is not available is demonstrated. Some kinetic consequences of the combination of elementary reactions to produce chain reactions are reviewed. Critical structural and kinetic features that determine the selectivity among product types and the response of reactions to temperature and substrate concentration are indicated. (C) 2000 Published by Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Poutsma, ML (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 89 TC 49 Z9 51 U1 3 U2 30 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-2370 J9 J ANAL APPL PYROL JI J. Anal. Appl. Pyrolysis PD MAR PY 2000 VL 54 IS 1-2 BP 5 EP 35 DI 10.1016/S0165-2370(99)00083-2 PG 31 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 291FA UT WOS:000085722400002 ER PT J AU Franz, JA Camaioni, DM Autrey, T Linehan, JC Alnajjar, MS AF Franz, JA Camaioni, DM Autrey, T Linehan, JC Alnajjar, MS TI Measurement of select radical processes in hydrocarbon pyrolysis SO JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS LA English DT Review DE pyrolysis; spectroscopy; KLS ID ABSOLUTE RATE CONSTANTS; SCAN FT-IR; ELECTRON-PARAMAGNETIC RESONANCE; RESOLVED STEP-SCAN; TERTIARY ALKYL RADICALS; TRANSIENT FREE-RADICALS; ATOM-TRANSFER-REACTIONS; HYDROGEN-ATOM; SPIN RESONANCE; INFRARED-SPECTROSCOPY AB Methods for the measurement of absolute and relative rates of reactions of organic free radicals related to hydrocarbon pyrolysis in the condensed phase are illustrated, Examples are provided of methods for the determination of absolute rate expressions. The absolute rate expressions are employed in competition kinetic experiments that measure the ratio of an unknown rate constant to the known basis rate constant, yielding the desired competing reaction rate. Examples of use of the absolute and competition kinetic methods to measure rates of select free radical reactions of interest to hydrocarbon pyrolysis are illustrated. Methods for the measurement of absolute rate expressions for reactions of organic free radicals that will be covered include kinetic laserflash optical spectroscopy (KLS), kinetic electron spin resonance spectroscopy (KESR), and kinetic laserflash time resolved infrared spectroscopy (TRIR). (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 99 TC 14 Z9 17 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-2370 EI 1873-250X J9 J ANAL APPL PYROL JI J. Anal. Appl. Pyrolysis PD MAR PY 2000 VL 54 IS 1-2 BP 37 EP 64 DI 10.1016/S0165-2370(99)00079-0 PG 28 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 291FA UT WOS:000085722400003 ER PT J AU Buchanan, AC Britt, PF AF Buchanan, AC Britt, PF TI Investigations of restricted mass transport effects on hydrocarbon pyrolysis mechanisms through silica immobilization SO JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS LA English DT Article DE hydrocarbon pyrolysis; silica immobilization; mass transport ID TEMPERATURE-PROGRAMMED REDUCTION; ORGANIC SULFUR FORMS; RADICAL CHAIN DECOMPOSITION; COAL SUB-STRUCTURES; SOLID-STATE; REACTION PATHWAYS; FLASH PYROLYSIS; MODEL COMPOUNDS; DISPERSED CATALYSTS; THERMAL-BEHAVIOR AB In the pyrolysis of polymers and other macromolecular systems including coal, kerogen, lignin, and cellulose, the importance of mass transport in affecting pyrolysis kinetics, tar and char yields, and product molecular weight distribution is becoming increasingly appreciated. However, detailed molecular level information on the effects of restricted mass transport on the reaction mechanisms for organic constituents in these complex organic materials is understandably more limited. Well-designed, experimental studies of the pyrolysis of model compounds and polymers are capable of providing such insights. In this paper, research employing silica-immobilized compounds is reviewed and selected examples from other types of model systems that explore mass transport effects are presented. (C) 2000 Published by Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Buchanan, AC (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, 1 Bethel Valley Rd,POB 2008, Oak Ridge, TN 37831 USA. NR 86 TC 13 Z9 13 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-2370 J9 J ANAL APPL PYROL JI J. Anal. Appl. Pyrolysis PD MAR PY 2000 VL 54 IS 1-2 BP 127 EP 151 DI 10.1016/S0165-2370(99)00078-9 PG 25 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 291FA UT WOS:000085722400007 ER PT J AU Paine, A Berkowitz, C AF Paine, A Berkowitz, C TI Tenth Joint Conference on Applications of Air Pollution Meteorology with the Air and Waste Management Association SO JOURNAL OF APPLIED METEOROLOGY LA English DT Editorial Material C1 ENSR Corp, Acton, MA 01720 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Paine, A (reprint author), ENSR Corp, Acton, MA 01720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD MAR PY 2000 VL 39 IS 3 BP 273 EP 274 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 298QL UT WOS:000086150600001 ER PT J AU Bowen, BM Baars, JA Stone, GL AF Bowen, BM Baars, JA Stone, GL TI Nocturnal wind direction shear and its potential impact on pollutant transport SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article; Proceedings Paper CT 10th Joint Conference on the Applications of Air Pollution Meteorology with the A&WMA / American-Meteorological-Society CY JAN 11-16, 1998 CL PHOENIX, ARIZONA SP Air & Waste Management Assoc, Amer Meteorol Soc ID COMPLEX TERRAIN; FLOWS AB The potential effects of vertical wind direction shear on pollutant transport at a complicated, semiarid site are examined using tower measurements. This high-elevation site is situated on a sloping plateau between mountains to the west and a river valley to the east. The local climate, which favors clear skies, low humidity, and light winds, permits terrain-generated winds to develop frequently. During the night, winds that are oriented along the valley frequently overlie shallow (<50-m deep) drainage winds. Results indicate the nighttime direction, hear between the levels at 92 and 12 m above ground exceeds 60 degrees 20% of the time and exceeds 20 degrees 50% of the time. Daytime shear is more modest: it is less than 20 degrees 90% of the time. The effects of vertical wind direction shear on plume transport are studied by performing two model simulations of release at 50 m above ground level during a period when strong directional shear persisted for several hours. the simulation using the full wind profile, southwest winds above a shallow drainage layer initially transport material to a community located 2 km to the northeast of the release. However. when only the 12-m wind is used, the model predicts that the material impacts a different community located 10 km to the southeast. This simulation demonstrates that ignoring the vertical shear effects can result in serious mistakes in responding to an emergency. C1 Univ Calif Lawrence Livermore Natl Lab, Natl Atmospher Release Advisory Ctr, Livermore, CA 94550 USA. Univ Calif Los Alamos Natl Lab, Air Qual Dept, Los Alamos, NM USA. RP Bowen, BM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Natl Atmospher Release Advisory Ctr, L-103,POB 808, Livermore, CA 94550 USA. NR 15 TC 7 Z9 7 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD MAR PY 2000 VL 39 IS 3 BP 437 EP 445 DI 10.1175/1520-0450(2000)039<0437:NWDSAI>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 298QL UT WOS:000086150600013 ER PT J AU Karabulut, M Marasinghe, GK Ray, CS Waddill, GD Day, DE Badyal, YS Saboungi, ML Shastri, S Haeffner, D AF Karabulut, M Marasinghe, GK Ray, CS Waddill, GD Day, DE Badyal, YS Saboungi, ML Shastri, S Haeffner, D TI A high energy x-ray and neutron scattering study of iron phosphate glasses containing uranium SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID EXTENDED-RANGE ORDER; STRUCTURAL-PROPERTIES; INTERMEDIATE-RANGE; DIFFRACTION; SILICA AB The atomic structure of iron phosphate glasses containing uranium has been studied by complementary neutron and x-ray scattering techniques. By combining x-ray and neutron structure factors, detailed information about different pair interactions has been obtained. Most of the basic structural features such as coordination numbers and O-O and P-O distances in uranium containing glasses are the same as those in the base glass of batch composition 40Fe(2)O(3)-60P(2)O(5) (mol %). However, the Fe-O distances change slightly with the addition of uranium. The observed structural parameters support a structural model in which the waste elements occupy voids in the Fe-O-P network, hence, not altering the basic structure of the parent iron phosphate glass. (C) 2000 American Institute of Physics. [S0021-8979(00)02605-0]. C1 Univ Missouri, Dept Phys, Rolla, MO 65401 USA. Univ Missouri, Dept Ceram Engn, Rolla, MO 65401 USA. Univ Missouri, Grad Ctr Mat Res, Rolla, MO 65401 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Karabulut, M (reprint author), Univ Missouri, Dept Phys, Rolla, MO 65401 USA. RI Saboungi, Marie-Louise/C-5920-2013 OI Saboungi, Marie-Louise/0000-0002-0607-4815 NR 30 TC 25 Z9 26 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2000 VL 87 IS 5 BP 2185 EP 2193 DI 10.1063/1.372160 PG 9 WC Physics, Applied SC Physics GA 287WK UT WOS:000085529500021 ER PT J AU Poonawala, N Dravid, VP Auciello, O Im, J Krauss, AR AF Poonawala, N Dravid, VP Auciello, O Im, J Krauss, AR TI Transmission electron microscopy study of hydrogen-induced degradation in strontium bismuth tantalate thin films SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MEMORIES AB The fabrication of nonvolatile ferroelectric random access memories based on SrBi2Ta2O9 (SBT) or other ferroelectric capacitors require exposure of these capacitors to processing gases mixtures including hydrogen. This results in a strong degradation of the capacitor electrical properties, mainly due to the interaction of hydrogen with the ferroelectric layer. Using surface analysis methods, we previously determined that the hydrogen-induced degradation of SBT capacitors might be partially due to the degradation of the near surface region of the SBT layer. It was also demonstrated that oxygen annealing after the hydrogen exposure results in the recovery of the degraded SBT surface layer and the electrical properties of the capacitor. We have now performed detailed cross sectional transmission electron microscopy studies of virgin, hydrogen, and oxygen annealed SBT/Pt/TiO2/SiO2/Si heterostructures. These studies combined microstructural imaging with a nanoscale compositional analysis of the SBT layer as a function of depth from the free surface of the film and across grain boundaries. High resolution energy dispersive x-ray spectroscopy revealed that hydrogen annealed SBT layers have a deficiency of Bi up to a depth of similar to 30 nm underneath the free surface, and that there is accumulation of Bi at the grain boundaries of pristine, hydrogen, and oxygen-recovery annealed SBT layers. This suggests that the diffusion of Bi is largely controlled by grain boundaries and they play a critical role in controlling the electrical properties of SBT capacitors. (C) 2000 American Institute of Physics. [S0021-8979(00)08604-7]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Auciello, O (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Dravid, Vinayak/B-6688-2009 NR 8 TC 22 Z9 22 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2000 VL 87 IS 5 BP 2227 EP 2231 DI 10.1063/1.372165 PG 5 WC Physics, Applied SC Physics GA 287WK UT WOS:000085529500026 ER PT J AU Kasnavi, R Sun, Y Mo, R Pianetta, P Griffin, PB Plummer, JD AF Kasnavi, R Sun, Y Mo, R Pianetta, P Griffin, PB Plummer, JD TI Characterization of arsenic dose loss at the Si/SiO2 interface SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SIO2/SI INTERFACE; SILICON; SEGREGATION; OXIDATION; DIFFUSION; DAMAGE; MODEL AB Careful sample preparation and secondary ion mass spectroscopy have been used to characterize arsenic dose loss to the silicon-oxide interface. Using high resolution x-ray photoelectron spectroscopy for microprofiling, we have directly observed the pileup of arsenic at the silicon dioxide-silicon interface. At least half of the pileup is shown to be on the silicon side of the interface in the first monolayer of silicon. Monolayer chemical oxidation and etching are successfully used to profile this pileup in silicon. This pileup contains most of the arsenic dose loss that occurs during transient enhanced diffusion. This result is crucial to correctly model the dose loss and provides physical justification for using a trap/detrap model at the interface, which is necessary to account for the fact that the arsenic surface concentration remains constant during an anneal and the fact that the dose loss is partially reversible. Finally, we have found that normal etching of the oxide in dilute hydroflouric acid and subsequent rinsing in water and exposure to air causes a permanent loss in arsenic dose. (C) 2000 American Institute of Physics. [S0021-8979(00)03004-8]. C1 Stanford Univ, Ctr Integrated Syst, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Kasnavi, R (reprint author), Stanford Univ, Ctr Integrated Syst, Stanford, CA 94305 USA. NR 16 TC 40 Z9 40 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2000 VL 87 IS 5 BP 2255 EP 2260 DI 10.1063/1.372169 PG 6 WC Physics, Applied SC Physics GA 287WK UT WOS:000085529500030 ER PT J AU Kessick, R Tepper, G Lee, E James, R AF Kessick, R Tepper, G Lee, E James, R TI Contactless thermally stimulated lifetime measurements in detector-grade cadmium zinc telluride SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CAVITY PERTURBATION TECHNIQUE; GAMMA-RAY; MICROWAVE AB Contactless thermally stimulated lifetime measurements were performed on detector-grade Cd1-xZnxTe (x similar to 0.1) crystals using a pulsed laser microwave cavity perturbation method. The carrier lifetime decreased from approximately 30 mu s at 110 K to 4 mu s at 160 K, and then remained relatively constant from 160 to 300 K. The sudden drop in carrier lifetime within a particular temperature range is consistent with the thermal activation of a charge trap with a detrapping time longer than the carrier lifetime. The maximum trap activation temperature and the minimum detrapping time are estimated from the lifetime versus temperature curve to be approximately 160 K and 10(-6) s, respectively. (C) 2000 American Institute of Physics. [S0021-8979(00)03605-7]. C1 Virginia Commonwealth Univ, Dept Chem Engn, Richmond, VA 23284 USA. Sandia Natl Labs, Livermore, CA 94551 USA. RP Tepper, G (reprint author), Virginia Commonwealth Univ, Dept Chem Engn, Richmond, VA 23284 USA. NR 13 TC 10 Z9 10 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2000 VL 87 IS 5 BP 2408 EP 2412 DI 10.1063/1.372193 PG 5 WC Physics, Applied SC Physics GA 287WK UT WOS:000085529500055 ER PT J AU Carmody, M Moeckly, BH Merkle, KL Marks, LD AF Carmody, M Moeckly, BH Merkle, KL Marks, LD TI Spatial variation of the current in grain boundary Josephson junctions SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID YBA2CU3O7-DELTA THIN-FILMS; MAGNETIC-FIELD; WEAK LINKS; DENSITY AB The spatial variation of the current across the boundary in several YBa2Cu3O7-x grain boundary Josephson junctions was determined using direct methods. A phase retrieval algorithm was used to calculate the positional critical current density J(x) from critical current versus applied magnetic field, I-c(B), measurements. The current distributions were highly nonuniform along the length of the junctions. These measurements are consistent with existing filamentary grain boundary models, low temperature scanning microscopy studies, and laser scanning microscopy studies of high T-c grain boundaries. The very large scatter in the critical currents reported in the literature for grain boundaries of the same macroscopic geometry appear to be due to the underlying variations in local critical currents. (C) 2000 American Institute of Physics. [S0021-8979(00)01905-8]. C1 Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Sci Technol Ctr Superconduct, Argonne, IL 60439 USA. Conductus Inc, Sunnyvale, CA 94086 USA. RP Carmody, M (reprint author), Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RI Marks, Laurence/B-7527-2009 NR 34 TC 9 Z9 9 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2000 VL 87 IS 5 BP 2454 EP 2459 DI 10.1063/1.372201 PG 6 WC Physics, Applied SC Physics GA 287WK UT WOS:000085529500063 ER PT J AU Budhani, RC Roy, C Lewis, LH Li, QA Moodenbaugh, AR AF Budhani, RC Roy, C Lewis, LH Li, QA Moodenbaugh, AR TI Magnetic ordering and granularity effects in La1-xBaxMnO3 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID COLOSSAL MAGNETORESISTANCE; NEGATIVE MAGNETORESISTANCE; GIANT MAGNETORESISTANCE; PEROVSKITES; FILMS; LAMNO3+DELTA AB We report detailed measurements of the magnetic behavior of La1-xBaxMnO3 bulk samples over a wide range of composition (0 less than or equal to x less than or equal to 1), temperature (4.2-775 K), and magnetic field strength (1 G-50 kG). The end members of this series namely LaMnO3+delta (with delta greater than or equal to 0) and BaMnO3 crystallize into pseudocubic perovskite and hexagonal lattices, respectively. The perovskite structure is stable for x less than or equal to 0.35 while a phase separation into La0.65Ba0.35MnO3 and BaMnO3 occurs for x > 0.35. The ordered moment on LaMnO3+delta depends sensitively on the processing conditions and the lowest value of 0.006 mu(B) per Mn ion at 4.2 K is realized in the antiferromagnetic compound of delta=0. The complex magnetic behavior of BaMnO3 suggests antiferromagnetic ordering below similar to 150 K. The Ba-substituted compounds order ferromagnetically with a monotonic increase of T-C and saturation magnetization M-s with x < 0.35. In the two-phase region, M-s scales with the fraction of the ferromagnetic phase present in the sample. Magnetic granularity, superparamagnetism, and an effective medium approach for susceptibility of the two-phase mixture are discussed. (C) 2000 American Institute of Physics. [S0021-8979(00)04104-9]. C1 Indian Inst Technol, Kanpur 208016, Uttar Pradesh, India. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Budhani, RC (reprint author), Indian Inst Technol, Kanpur 208016, Uttar Pradesh, India. NR 28 TC 13 Z9 13 U1 0 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 2000 VL 87 IS 5 BP 2490 EP 2496 DI 10.1063/1.372208 PG 7 WC Physics, Applied SC Physics GA 287WK UT WOS:000085529500070 ER PT J AU Richardson, SJ Splitt, ME Lesht, BM AF Richardson, SJ Splitt, ME Lesht, BM TI Enhancement of ARM Surface Meteorological Observations during the Fall 1996 Water Vapor Intensive Observation Period SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article AB This work describes in situ moisture sensor comparisons that were performed in conjunction with the first Water Vapor Intensive Observation Period (IOP) conducted at the Atmospheric Radiation Measurement (ARM) Program Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site during September of 1996. Two Raman lidars, two Atmospheric Emitted Radiance Interferometers. (AERIs), and a suite of 13 microwave radiometers were assembled at the CART site during the IOP. and in situ measurements were used for calibration and verification. In addition, this work was meant to help assess the current observing strategy in an effort to make improvements to the routine continuous measurements. To accomplish these goals, verification of the in situ measurements was required. Therefore, a laboratory intercomparison of the in situ moisture sensors (nine capacitive chip relative humidity sensors and four chilled mirror sensors) was performed at the Oklahoma Mesonet temperature and relative humidity testing and calibration facility. Tests were conducted both before and after the instruments were used in the IOP. making it possible to detect instrument problems prior to the IOP and to determine if instrument failure or drift occurred during the IOP. Preliminary results comparing in situ moisture measurements with remotely sensed atmospheric moisture will be presented and additional applications will be discussed. As a consequence of this work, modifications were made to the ARM CART calibration procedures. and there are now redundant temperature and relative humidity measurements so that sensor drift or calibration errors may be detected. These modifications: to the observation and calibration strategy led to improvements in the continuous routine measurements at the ARM CART site. C1 Univ Oklahoma, Sch Meteorol, Norman, OK 73019 USA. Univ Utah, Salt Lake City, UT USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Richardson, SJ (reprint author), Cooperat Inst Mesoscale Meteorol Studies, 100 E Boyd St,Suite 1110, Norman, OK 73019 USA. OI Splitt, Michael/0000-0002-7690-5100 NR 12 TC 10 Z9 10 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD MAR PY 2000 VL 17 IS 3 BP 312 EP 322 DI 10.1175/1520-0426(2000)017<0312:EOASMO>2.0.CO;2 PG 11 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 291FP UT WOS:000085723700004 ER PT J AU Saka, O Akaki, H Reeves, GD Baker, DN AF Saka, O Akaki, H Reeves, GD Baker, DN TI Magnetic fields and particle signatures in the vicinity of nightside geosynchronous altitudes in the first one-minute-interval of pi 2 onset: a case study (vol 62, pg 17, 2000) SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Correction C1 Kurume Natl Coll Technol, Dept Phys, Kurume, Fukuoka, Japan. Kyushu Univ, Dept Earth & Planetary Sci, Fukuoka 812, Japan. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. RP Saka, O (reprint author), Kurume Natl Coll Technol, Dept Phys, Kurume, Fukuoka, Japan. NR 1 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD MAR PY 2000 VL 62 IS 5 BP 395 EP 395 DI 10.1016/S1364-6826(00)00051-1 PG 1 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 320WW UT WOS:000087424700005 ER PT J AU Riccillo, PM Muglia, CI de Bruijn, FJ Roe, AJ Booth, IR Aguilar, OM AF Riccillo, PM Muglia, CI de Bruijn, FJ Roe, AJ Booth, IR Aguilar, OM TI Glutathione is involved in environmental stress responses in Rhizobium tropici, including acid tolerance SO JOURNAL OF BACTERIOLOGY LA English DT Article ID PHASEOLUS-VULGARIS L; ESCHERICHIA-COLI; SINORHIZOBIUM-MELILOTI; POTASSIUM CHANNELS; NITROGEN-FIXATION; FLANKING REGIONS; GENE; PH; CYANOBACTERIUM; EXPRESSION AB The isolation of rhizobial strains which exhibit an intrinsic tolerance to acidic conditions has been reported and has facilitated studies on the basic mechanisms underlying acid tolerance. Rhizobium tropici strain CIAT899 displays a high intrinsic tolerance to acidity and therefore was used in this work to study the molecular basis of bacterial responses to acid conditions and other environmental stresses. We generated a collection of R, tropici CIAT899 mutants affected in acid tolerance using Tn5-luxAB mutagenesis, and one mutant strain (CIAT899-13T2), which fails to grow under acid conditions, was characterized in detail. Strain CIAT899-13T2 was found to contain a single Tn5-luxAB insertion in a gene showing a high degree of similarity with the Escherichia coli gshB gene, encoding the enzyme glutathione synthetase. Intracellular potassium pools and intracellular pH levels were found to be lower in the mutant than in the parent. The glutathione-deficient mutant was shown to be sensitive to weak organic acids, osmotic and oxidative stresses, and the presence of methylglyoxal. Glutathione restores responses to these stresses almost to wild-type levels; Our data show that in R. tropici the production of glutathione is essential for growth in extreme environmental conditions. The mutant strain CIAT899-13T2 induced effective nodules; however, it was found to be outcompeted by the wild-type strain in coinoculation experiments. C1 Natl Univ La Plata, Fac Ciencias Exactas, Inst Bioquim & Biol Mol, RA-1900 La Plata, Argentina. Michigan State Univ, DOE Plant Res Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Microbiol, E Lansing, MI 48824 USA. Univ Aberdeen, Inst Med Sci, Dept Mol & Cell Biol, Aberdeen AB25 2ZD, Scotland. RP Aguilar, OM (reprint author), Natl Univ La Plata, Fac Ciencias Exactas, Inst Bioquim & Biol Mol, Calles 47 & 115, RA-1900 La Plata, Argentina. NR 45 TC 74 Z9 85 U1 0 U2 10 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0021-9193 J9 J BACTERIOL JI J. Bacteriol. PD MAR PY 2000 VL 182 IS 6 BP 1748 EP 1753 DI 10.1128/JB.182.6.1748-1753.2000 PG 6 WC Microbiology SC Microbiology GA 288VK UT WOS:000085585000034 PM 10692382 ER PT J AU Pujuguet, P Simian, M Liaw, J Timpl, R Werb, Z Bissell, MJ AF Pujuguet, P Simian, M Liaw, J Timpl, R Werb, Z Bissell, MJ TI Nidogen-1 regulates laminin-1-dependent mammary-specific gene expression SO JOURNAL OF CELL SCIENCE LA English DT Article DE nidogen-1; entactin; basement membrane; extracellular matrix; tissue-specific gene expression; epithelial-mesenchymal interaction; mammary gland ID BRANCHING EPITHELIAL MORPHOGENESIS; BASEMENT-MEMBRANE FORMATION; COLLAGEN TYPE-IV; EXTRACELLULAR-MATRIX; CELL-DIFFERENTIATION; SUBMANDIBULAR-GLAND; LAMININ GAMMA-1; CANCER-CELLS; IN-VITRO; ENTACTIN AB Nidogen-1 (entactin) acts as a bridge between the extracellular matrix molecules laminin-1 and type TV collagen, and thus participates in the assembly of basement membranes. To investigate the role of nidogen-1 in regulating cell-type-specific gene expression in mammary epithelium, we designed a culture microecosystem in which each component, including epithelial cells, mesenchymal cells, lactogenic hormones and extracellular matrix, could be controlled. We found that primary and established mesenchymal and myoepithelial cells synthesized and secreted nidogen-1, whereas expression was absent in primary and established epithelial cells. In an epithelial cell line containing mesenchymal cells, nidogen-1 was produced by the mesenchymal cells but deposited between the epithelial cells. In this mixed culture, mammary epithelial cells express beta-casein in the presence of lactogenic hormones, Addition of either laminin-1 plus nidogen-1, or laminin-1 alone, to mammary epithelial cells induced beta-casein production. We asked whether recombinant nidogen-1 alone could signal directly for beta-casein. Nidogen-1 did not induce beta-casein synthesis in epithelial cells, but it augmented the inductive capacity of laminin-1. These data suggest that nidogen-1 can cooperate with laminin-1 to regulate beta-casein expression, Addition of full-length nidogen-1 to the mixed cultures had no effect on beta-casein gene expression; however, a nidogen-1 fragment containing the laminin-1 binding domain, but lacking the type IV collagen-binding domain, had a dominant negative effect on beta-casein expression. These data point to a physiological role for nidogen-1 in the basement membrane-induced gene expression by epithelial cells. C1 Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. Max Planck Inst Biochem, D-82152 Martinsried, Germany. Univ Calif San Francisco, Dept Anat, San Francisco, CA 94143 USA. RP Bissell, MJ (reprint author), Lawrence Berkeley Natl Lab, Div Life Sci, 1 Cyclotron Rd,83-101, Berkeley, CA 94720 USA. FU NCI NIH HHS [R01 CA057621, R01 CA057621-07, CA-57621] NR 49 TC 43 Z9 44 U1 0 U2 1 PU COMPANY OF BIOLOGISTS LTD PI CAMBRIDGE PA BIDDER BUILDING CAMBRIDGE COMMERCIAL PARK COWLEY RD, CAMBRIDGE CB4 4DL, CAMBS, ENGLAND SN 0021-9533 J9 J CELL SCI JI J. Cell Sci. PD MAR PY 2000 VL 113 IS 5 BP 849 EP 858 PG 10 WC Cell Biology SC Cell Biology GA 298RL UT WOS:000086152900012 PM 10671374 ER PT J AU Bonner, NA Willes, EH AF Bonner, NA Willes, EH TI Tracer diffusion and electric mobility of ions in aqueous solutions: A method for estimating the average charge of complex ions SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article AB In the study of complex ions in aqueous solution it is useful to know the charge on the ion being studied. The Nernst equation implies a linear relationship between the charge (z) and the ratio of the electric mobility (mu) to the diffusion coefficient (D). The equation is strictly valid only at infinite dilution, but it might be assumed that the relationship in real solutions would be a fairly simple one. We have tested the assumption by measuring the values of mu and D for a group of cations at low concentration in 1 M HClO4. The ions measured were those of Na, Rb, Cs, Be, Co, Zn, Sr, Cr, Fe, Y, and Eu. The relationship is not linear but can be described by a function of the form z = A (1 - e(-Bz)), where A and B are empirically determined constants. We used radioactive tracers to make the measurements. C1 Univ Calif Lawrence Livermore Natl Lab, Analyt & Nucl Chem Div, Livermore, CA 94550 USA. RP Bonner, NA (reprint author), 1093 Nielsen Lane, Livermore, CA 94550 USA. NR 27 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD MAR-APR PY 2000 VL 45 IS 2 BP 324 EP 330 DI 10.1021/je9902544 PG 7 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 294GG UT WOS:000085903000039 ER PT J AU Bacon, JA Pratt, ST AF Bacon, JA Pratt, ST TI Photoelectron spectroscopy of autoionizing Rydberg states of ammonia SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TRIPLE-RESONANCE SPECTROSCOPY; HIGHER EXCITED-STATES; VIBRATIONAL AUTOIONIZATION; MULTIPHOTON IONIZATION; FLUORESCENCE EXCITATION; MODE SPECIFICITY; HIGH-RESOLUTION; H-2; PHOTOIONIZATION; NO2 AB Photoelectron spectroscopy was used to determine the ionic vibrational distributions following vibrational autoionization of Rydberg states of NH3. Two-color, two-photon resonant, three-photon excitation via selected rotational levels of the NH3 (C) over tilde' (1)A(1)'(0200) intermediate state was employed to populate vibrationally autoionizing Rydberg states between the v(2)(+)=1 and v(2)(+)=2 ionization thresholds of the NH3+ (X) over tilde (2)A(2)" ground electronic state. As expected from the propensity rule for vibrational autoionization, ionization with Delta v(2)=-1 was found to be the dominant process. The observed vibrational distributions appear to be independent of the rotational quantum number of the autoionizing state. Partially resolved rotational structure was exhibited within the photoelectron spectra providing information on the assignments of the Rydberg states and on the mechanism for vibrational autoionization. (C) 2000 American Institute of Physics. [S00219606(00)00109-4]. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Bacon, JA (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 40 TC 6 Z9 6 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 1 PY 2000 VL 112 IS 9 BP 4153 EP 4161 DI 10.1063/1.480962 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 286QA UT WOS:000085455600028 ER PT J AU Brito, HF Liu, GK AF Brito, HF Liu, GK TI Crystal field influence on the S-8(7/2) ground state splitting of Bk4+ in CeF4 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ACTINIDE TETRAFLUORIDES; SYSTEMATIC ANALYSIS; SPECTRA; CM3+; FLUORESCENCE; LACL3; LUPO4; IONS; GD3+ AB The one-particle models of crystal-field theory provide a qualitative interpretation for the observed ground state splitting of four Kramers doublets of the S-8(7/2) of Bk4+ doped into CeF4. A set of nine nonzero (B-q(k)) parameters corresponding a C-2v point symmetry provide a very good correlation between the experimental data and simulated energy level schemes within a rms deviation of 13.7 cm(-1). The calculated and experimental energy values have the same order-of-magnitude for the ground state and excited components. The total ground state splitting of the S-state ions of f-elements such as Bk4+ in CeF4 is larger when compared with Cm3+:LaCl3 and Gd3+:La(C2H5SO4)(3). 9H(2)O ions. The so-called crystal-field strength parameter, N-v, increases as a function of the increasing maximum splitting of the ground state due to a decrease in the participation of the pure S-8(7/2) in the final composition of the ground state eigenvector. (C) 2000 American Institute of Physics. [S0021-9606(00)70509-5]. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Univ Fed Sao Paulo, Inst Quim, BR-05599970 Sao Paulo, Brazil. RP Brito, HF (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Brito, Hermi/I-4392-2012; Institute of Chemistry - USP, Dept. of Chemistry/B-8988-2012 NR 42 TC 23 Z9 23 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 1 PY 2000 VL 112 IS 9 BP 4334 EP 4341 DI 10.1063/1.480980 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 286QA UT WOS:000085455600049 ER PT J AU Luo, S Burns, CJ Kubas, GJ Bryan, JC Crabtree, RH AF Luo, S Burns, CJ Kubas, GJ Bryan, JC Crabtree, RH TI Reactions of ReH3(CO)(PMe2Ph)(3) with metallic Lewis acids. Synthesis and structural characterization of hydride-bridged heterometallic rhenium-gold, rhenium-silver, and rhenium-copper complexes SO JOURNAL OF CLUSTER SCIENCE LA English DT Review DE heterometallic; hydride; cluster; rhenium; coinage metal ID RAY CRYSTAL-STRUCTURE; HETERONUCLEAR CLUSTER CHEMISTRY; GROUP 1B METALS; M = CU; MOLECULAR-STRUCTURE; DYNAMIC BEHAVIOR; HETEROBIMETALLIC COMPLEXES; TANTALOCENE TRIHYDRIDE; POLYHYDRIDE COMPLEXES; BIMETALLIC COMPLEXES AB This contribution presents a study of the reactions of ReH3(CO)(PMe2Ph)(3) (1) with a variety of metallic Lewis acids of the coinage metals to form hydrido-bridged heterometallic rhenium-gold, rhenium-silver, and rhenium-copper complexes. The reaction of 1 with AuCl(PPh3) proceeds with elimination of hydrogen to give the hydride-bridged heterobinuclear rhenium-gold complex (PMe2Ph)(3)(CO)ClRe(mu-H)Au(PPh3) (2). In contrast, the reactions of 1 with AgPF6, [Cu(CH3CN)(4)]PF6 or CuCl proceed without elimination of hydrogen to give the hydride-bridged heterotrinuclear rhenium-silver and rhenium-copper complexes [(PMe2Ph)(3)(CO)HRe(mu-H)(2)M(mu-H)(2)ReH(CO)(PMe2Ph)(3)]PF6 (M = Ag (3), Cu (4)) and the hydride-bridged heterotetranuclear rhenium-copper complex (PMe2Ph)(3)(CO)HRe(mu-H)(2)Cu(mu-Cl)(2)Cu(mu-H)(2)ReH(CO)(PMe2Ph)(3) (5), respectively. The molecular structures of compounds 2 and 3 have been determined by single-crystal X-ray diffraction studies. Crystallographic data for 2: monoclinic, space group P2(1)2(1)2(1), a=12.804(2) Angstrom, b=13.512(2) Angstrom, c=24.312(3) Angstrom, V=4206(1) Angstrom(3), Z = 4, and R = 0.042. Crystallographic data for 3: monoclinic, space group C2/c, a = 24.212(6) Angstrom, b = 13.098(3) Angstrom, c = 20.177(5) Angstrom, b=116.40(2)degrees, V=5732(2) Angstrom(3), Z=4, and R=0.044. The X-ray crystal structure of 2 exhibits a short contact (2.798(12) Angstrom) between the gold atom and the CO ligand that is primarily bound to the adjacent rhenium atom, suggesting an incipient semibridging relationship. C1 Bridgestone Firestone Inc, Cent Res Dept, Akron, OH 44317 USA. Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Yale Univ, Dept Chem, New Haven, CT 06520 USA. RP Luo, S (reprint author), Bridgestone Firestone Inc, Cent Res Dept, 1200 Firestone Pkwy, Akron, OH 44317 USA. NR 130 TC 7 Z9 7 U1 1 U2 7 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1040-7278 J9 J CLUST SCI JI J. Clust. Sci. PD MAR PY 2000 VL 11 IS 1 BP 189 EP 216 DI 10.1023/A:1009073017138 PG 28 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 296HT UT WOS:000086019500015 ER PT J AU Sytine, IV Porter, DH Woodward, PR Hodson, SW Winkler, KH AF Sytine, IV Porter, DH Woodward, PR Hodson, SW Winkler, KH TI Convergence tests for the piecewise parabolic method and Navier-Stokes solutions for homogeneous compressible turbulence SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE turbulence modeling; homogeneous compressible turbulence; Piecewise Parabolic Method; subgrid-scale models ID FLUID TRANSPORT ALGORITHM; LARGE-EDDY SIMULATION; NUMERICAL-SIMULATION; CORRECTED TRANSPORT; FLOWS; SPECTRA; SHASTA; WORKS AB The need to simulate fully developed turbulence with wide range of scales led us to use the Piecewise Parabolic Method (PPM) to solve the Euler equations of motions. To obtain data for 3-D homogeneous compressible decaying turbulence numerical simulations were performed on computational meshes of up to 1024(3) zones. These data were compared with data obtained by solving the Navier-Stokes (NS) equations. Results of studying the kinetic energy, enstrophy, and the energy power spectra with different resolutions are presented for both the PPM and NS data. The results of the comparison show convergence of the PPM and NS solutions to the same limit. (C) 2000 Academic Academic Press. C1 Univ Minnesota, Lab Computat Sci & Engn, Minneapolis, MN 55455 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sytine, IV (reprint author), Univ Minnesota, Lab Computat Sci & Engn, Minneapolis, MN 55455 USA. NR 28 TC 57 Z9 57 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAR 1 PY 2000 VL 158 IS 2 BP 225 EP 238 DI 10.1006/jcph.1999.6416 PG 14 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 292GT UT WOS:000085786500005 ER PT J AU Bantignies, JL Carr, GL Lutz, D Marull, S Williams, GP Fuchs, G AF Bantignies, JL Carr, GL Lutz, D Marull, S Williams, GP Fuchs, G TI Chemical imaging of hair by infrared microspectroscopy using synchrotron radiation SO JOURNAL OF COSMETIC SCIENCE LA English DT Article ID DRUG DISTRIBUTION; MICROSCOPY; SPECTROSCOPY; LIGHT AB For the first time, infrared microspectroscopy with a synchrotron source has been used to characterize human hair before and after bleaching. This high-brightness source allows a lateral resolution approaching the diffract ion limit (a few microns) to be achieved. Thus, 4-micron diameter areas have been analyzed, and chemical imaging of hair cross sections obtained with good contrast. In particular, the variations of the integrated absorbances of the amide stretching vibration (3230 cm(-1)) and CH stretching vibrations (between 3000 and 2800 cm(-1)) as a function of sample position have allowed chemical imaging of the medulla and cuticle. We also studied bleaching of the hair, and we checked different chemical effects as a function of position in the hair cross section. We also observed a non-homogeneous distribution of bonded water. The transformation, due to breakage of a specific chemical group, was observed and spatially characterized. The sulphonate contributions were given special attention and showed non-homogeneous distributions within the hair. C1 Elf Atochem Co, CRRA, F-69310 Pierre Benite, France. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. Yves Rocher Co, F-92444 Issy Les Moulineaux, France. RP Marull, S (reprint author), Elf Atochem Co, CRRA, Rue Henri Moissan,BP 63, F-69310 Pierre Benite, France. NR 22 TC 15 Z9 15 U1 0 U2 6 PU SOC COSMETIC CHEMISTS PI NEW YORK PA 120 WALL STREET, SUITE 2400, NEW YORK, NY 10005-4088 USA SN 0037-9832 J9 J COSMET SCI JI J. Cosmet. Sci. PD MAR-APR PY 2000 VL 51 IS 2 BP 73 EP 90 PG 18 WC Chemistry, Applied; Dermatology SC Chemistry; Dermatology GA 324NM UT WOS:000087628300001 ER PT J AU Sopori, B Wei, C Yi, Z Madjdpour, J AF Sopori, B Wei, C Yi, Z Madjdpour, J TI High-speed mapping of grown-in defects and their influence in large-area silicon photovoltaic devices SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 8th International Conference on Defects - Recognition, Imaging and Physics in Semiconductors CY SEP 15-18, 1999 CL NARITA, JAPAN SP Japan Soc Promot Sci, Japan Soc Appl Phys, Gakushuin Univ, Ratoc Syst Engn Co, Shin Etsu Handotai Co, Mitsubishi Mat Corp, Rigaku Corp, Sharp Corp, Mitsui Min & Smelting Co, Atago Bussan Co, NEC Corp, Japan Energy Co AB A scanning system for mapping defects, and for measuring their influence on the photovoltaic of Si solar cells, is described. The system uses optical scattering patterns to identify the nature of defects. The local density of the defects is statistically determined from the integrated scattered light. The optical system can also measure the reflectance and the light-induced current which is then used to yield maps of the internal photoresponse of the device. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Sopori, B (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 3 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAR PY 2000 VL 210 IS 1-3 BP 346 EP 350 DI 10.1016/S0022-0248(99)00708-3 PG 5 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 294YA UT WOS:000085937200070 ER PT J AU Sopori, B Chen, W AF Sopori, B Chen, W TI Influence of distributed defects on the photoelectric characteristics of a large-area device SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 8th International Conference on Defects - Recognition, Imaging and Physics in Semiconductors CY SEP 15-18, 1999 CL NARITA, JAPAN SP Japan Soc Promot Sci, Japan Soc Appl Phys, Gakushuin Univ, Ratoc Syst Engn Co, Shin Etsu Handotai Co, Mitsubishi Mat Corp, Rigaku Corp, Sharp Corp, Mitsui Min & Smelting Co, Atago Bussan Co, NEC Corp, Japan Energy Co AB A network model is developed to analyze the effects of crystal defects on the performance of a large-area photovoltaic device. The model assembles local segments of the device as dark current generators whose values depend on the local defect densities. The values of the parameters for different defect densities are determined empirically. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Sopori, B (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 4 TC 19 Z9 19 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAR PY 2000 VL 210 IS 1-3 BP 375 EP 378 DI 10.1016/S0022-0248(99)00714-9 PG 4 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 294YA UT WOS:000085937200076 ER PT J AU McHugo, SA Thompson, AC Flink, C Weber, ER Lamble, G Gunion, B MacDowell, A Celestre, R Padmore, HA Hussain, Z AF McHugo, SA Thompson, AC Flink, C Weber, ER Lamble, G Gunion, B MacDowell, A Celestre, R Padmore, HA Hussain, Z TI Synchrotron-based impurity mapping SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 8th International Conference on Defects - Recognition, Imaging and Physics in Semiconductors CY SEP 15-18, 1999 CL NARITA, JAPAN SP Japan Soc Promot Sci, Japan Soc Appl Phys, Gakushuin Univ, Ratoc Syst Engn Co, Shin Etsu Handotai Co, Mitsubishi Mat Corp, Rigaku Corp, Sharp Corp, Mitsui Min & Smelting Co, Atago Bussan Co, NEC Corp, Japan Energy Co DE silicon; X-ray characterization; metal impurities; chemical state ID SILICON AB Studies were performed on metal impurity precipitates in silicon using synchrotron-based X-rays. The elemental distribution and chemical state of metal impurities were measured by using synchrotron-based X-ray fluorescence (mu-XRF) and X-ray absorption spectroscopy (mu-XAS), both with a 1-2 mu m(2) spatial resolution. With these systems we have identified preferred precipitation sites for metal impurities in silicon and we have correlated poor solar cell performance with metal impurity distributions. Furthermore, we have studied the dissolution rate of metal precipitates as a function of thermal treatment and we have analyzed the chemical state of metal precipitates in silicon. Discussions of metal precipitate stability are presented in regards to the chemical state and material improvement. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Lawrence Berkeley Natl Lab, Adv Light Source Div, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci, Berkeley, CA 94720 USA. RP McHugo, SA (reprint author), Lawrence Berkeley Natl Lab, Adv Light Source Div, MS 2-400,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 7 TC 36 Z9 36 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAR PY 2000 VL 210 IS 1-3 BP 395 EP 400 DI 10.1016/S0022-0248(99)00718-6 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 294YA UT WOS:000085937200080 ER PT J AU Cao, XA Zhang, AP Dang, GT Ren, F Pearton, SJ Van Hove, JM Hickman, RA Shul, RJ Zhang, L AF Cao, XA Zhang, AP Dang, GT Ren, F Pearton, SJ Van Hove, JM Hickman, RA Shul, RJ Zhang, L TI Plasma damage in p-GaN SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE GaN; plasma; damage; ICP; diodes ID ETCHING-INDUCED DAMAGE; SCHOTTKY DIODES; TRANSISTOR AB The effect of Inductively Coupled Plasma H-2 or Ar discharges on the breakdown voltage of p-GaN diodes was measured over a range of ion energies and fluxes. The main effect of plasma exposure is a decrease in net acceptor concentration to depths of 400-550 Angstrom. At high ion fluxes or energies there can be type conversion of the initially p-GaN surface. Post etch annealing at 900 degrees C restores the initial conductivity. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Blue Lotus Micro Devices, Eden Prairie, MN 55344 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Cao, XA (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 26 TC 17 Z9 18 U1 0 U2 8 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAR PY 2000 VL 29 IS 3 BP 256 EP 261 DI 10.1007/s11664-000-0059-7 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 349QJ UT WOS:000089056900003 ER PT J AU Roh, Y Edwards, NT Lee, SY Stiles, CA Armes, S Foss, JE AF Roh, Y Edwards, NT Lee, SY Stiles, CA Armes, S Foss, JE TI Thermal-treated soil for mercury removal: Soil and phytotoxicity tests SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article AB Mercury (Hg) contamination of soils and sediments is one of many environmental problems at the Oak Ridge Reservation, Oak Ridge, TN, Mercury-contaminated soil from the Lower East Fork Poplar Creek (LEFPC) at the Oak Reservation was treated thermally to reduce Mg concentration to a below target level (20 mg kg-L) as a pilot scale thermal treatment demonstration. As a part of performance evaluation, the soil characteristics and plant growth response of the untreated and treated soil were examined. The soil treated at 350 degrees C retained most of its original soil properties, hut the soil treated at 600 degrees C exhibited considerable changes in mineralogical composition and physicochemical characteristics. Growth and physiological response of the three plant species radish (Raphanus sativus L.), fescue (Festuca arundinacea Schreb.), and oat (Avena sativa L.) indicated adverse effects of the thermal treatment. The addition of N fertilizer had beneficial effects in the 350 degrees C treated soil, hut had little beneficial effects in the 600 degrees C treated soil. Some changes of soil characteristics induced by thermal treatment cannot be avoided. Soil characteristics and phytotoxicity test results strongly suggest that changes occurring following the 350 degrees C treatment do not limit the use of the treated soil to refill the excavated site for full-scale remediation. The only problem with the 350 degrees C treatment is that small amounts of Hg compounds (<15 mg kg(-1)) remain in the soil and a processing cost of $45/Mg. C1 Univ Tennessee, Dept Plant & Soil Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Roane State Community Coll, Student Assistance Program, Oak Ridge, TN 37831 USA. RP Roh, Y (reprint author), Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. NR 29 TC 8 Z9 9 U1 1 U2 6 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD MAR-APR PY 2000 VL 29 IS 2 BP 415 EP 424 PG 10 WC Environmental Sciences SC Environmental Sciences & Ecology GA 355WR UT WOS:000089412000007 ER PT J AU Jackson, BP Miller, WP AF Jackson, BP Miller, WP TI Soil solution chemistry of a fly ash-, poultry litter-, and sewage sludge-amended soil SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID LAND APPLICATION; BROILER LITTER; ECOSYSTEMS; DISPOSAL; RESIDUES; NITROGEN; MANURE; METALS; RUNOFF; COPPER AB Mixing coal fly ash (FA) with organic wastes to provide balanced soil amendments offers a potential viable use of this industrial byproduct. When such materials are land-applied to supply nutrients for agronomic crops, trace element contaminant solubility must be evaluated. In this study, major and trace element soil solution concentrations arising from application of fly ash, organic wastes, and mixtures of the two were compared in a laboratory incubation. Two fly ashes, broiler poultry litter (PL), municipal sewage sludge (SS), and mixtures of FA with either PL or SS were mixed with a Cecil sandy loam:(fine, kaolinitic, thermic Typic Kanhapludult) at rates of 32.3, 8.1, and 16.1g kg(-1) soil for FA, FL, and SS, respectively. Treatments were incubated at 22 degrees C at 17% moisture content and soil solution was periodically extracted by centrifugation over 33 d. Initial soil solution concentrations of As, Mo, Se, and Cu were significantly greater in FA/PL treatments than the respective FA-only treatments. For Cu, increased solution concentrations were attributable to increased loading rates in FA/PL mixtures. Solution Cu concentrations were strongly correlated with dissolved C (R-2 > 0.96) in all PL treatments. Significant interactive effects for solution Mo and Se concentrations were observed for the FA/PL and may have resulted from the increased pH and competing anion concentrations of these treatments. Solution As concentrations showed a significant interactive effect for one FA/PL mixture. For the individual treatments, As was more soluble in the PL treatment than either FA treatment. Except for soluble Se from one FA/SS mixture, trace element solubility in the FA/SS mixtures was not significantly different than the respective FA-only treatment. C1 Univ Georgia, Savannah River Ecol Lab, Adv Analyt Ctr Environm Sci, Aiken, SC 29803 USA. Univ Georgia, Dept Crop & Soil Sci, Athens, GA 30602 USA. RP Jackson, BP (reprint author), Univ Georgia, Savannah River Ecol Lab, Adv Analyt Ctr Environm Sci, Aiken, SC 29803 USA. NR 32 TC 33 Z9 36 U1 2 U2 11 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD MAR-APR PY 2000 VL 29 IS 2 BP 430 EP 436 PG 7 WC Environmental Sciences SC Environmental Sciences & Ecology GA 355WR UT WOS:000089412000009 ER PT J AU Garten, CT Wullschleger, SD AF Garten, CT Wullschleger, SD TI Soil carbon dynamics beneath switchgrass as indicated by stable isotope analysis SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID C-13 NATURAL-ABUNDANCE; ORGANIC-MATTER; CULTIVATION; INVENTORIES; TURNOVER; PARTICULATE; STORAGE; MODEL AB Surface (0-40 cm) soil organic carbon (SOC) dynamics were studied beneath four switchgrass (Panicum virgatum L.) field trials in the southeastern United States, Soil organic carbon was partitioned into particulate organic matter (POM) and mineral-associated organic matter (MOM). Most (75-90%) of the SOC at each study site was affiliated with MOM I (<0.053 mm), Changes in stable carbon isotope ratios were used to derive carbon inputs to and losses from PORI and MOM at each site. Inventories of existing SOC and new Cs derived SOC beneath switchgrass decreased with increasing soil depth. Approximately 5 Sr after establishment, 19 to 31% of the existing SOC inventories beneath switchgrass had been derived from new C-4-carbon inputs, Calculated turnover times of POM and MOM ranged from 2.4 to 4.3 yr and 26 to 40 Sr, respectively. The turnover time of SOC in the POM fraction increased with decreasing mean annual temperature, A simple, two-compartment model was parameterized to predict the potential fur soil carbon sequestration under switchgrass. An example calculation with the model indicated a measurable and verifiable recovery of soil carbon (approximate to 12% increase) on degraded lands through one decade of switchgrass production. The potential to sequester carbon through switchgrass cultivation will depend on initial soil carbon inventories, prevailing climate, soil type, and site management. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Garten, CT (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Wullschleger, Stan/B-8297-2012 OI Wullschleger, Stan/0000-0002-9869-0446 NR 30 TC 70 Z9 73 U1 0 U2 23 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD MAR-APR PY 2000 VL 29 IS 2 BP 645 EP 653 PG 9 WC Environmental Sciences SC Environmental Sciences & Ecology GA 355WR UT WOS:000089412000035 ER PT J AU Mykles, DL Haire, MF Skinner, DM AF Mykles, DL Haire, MF Skinner, DM TI Immunocytochemical localization of actin and tubulin in the integument of land crab (Gecarcinus lateralis) and lobster (Homarus americanus) SO JOURNAL OF EXPERIMENTAL ZOOLOGY LA English DT Article ID MULTICATALYTIC PROTEINASE PROTEASOME; CRUSTACEAN EXOSKELETON; CALLINECTES-SAPIDUS; MYOFIBRILLAR PROTEINS; CUTICULAR PROTEINS; SECRETORY PATHWAY; PLASMA-MEMBRANE; GENE FAMILY; MOLT-CYCLE; BLUE-CRAB AB The crustacean integument consists of the exoskeleton and underlying epithelium and associated tissues. The epithelium, which is composed of a single layer of cells, is responsible for the cyclical breakdown and synthesis of the exoskeleton associated with molting (ecdysis). During premolt (proecdysis) the epithelial cells lengthen and secrete the two outermost layers (epicuticle and exocuticle) of the new exoskeleton while partially degrading the two innermost layers (endocuticle and membranous layer) of the overlying old exoskeleton. This increased cellular activity is associated with increased protein synthesis and a change in cell shape from cuboidal to columnar. The cytoskeleton, composed of microfilaments (actin) and microtubules (tubulin), plays important roles in the intracellular organization and motility of eukaryotic cells. Immunoblot analy- sis shows that the land crab exoskeleton contains actin, tubulin, and actin-related proteins (Varadaraj et al. 1996. Gene 171:177-184). In the present study, immunocytochemistry of land crab and lobster integument showed that both proteins were localized in various cell types, including epithelia, connective tissue, tendinal cells, and blood vessels. Muscle immunostained for actin and myosin, but not for tubulin. The membranous layer of land crab (the other layers of the exoskeleton were not examined) and membranous layer and endocuticle of lobster also reacted specifically with anti-beta-actin and anti-alpha-tubulin monoclonal antibodies, but not with an anti-myosin heavy chain antibody. During proecdysis immunolabeling of the membranous layer decreased probably due to protein degradation. The staining intensity for actin and tubulin in the proecdysial epithelium was similar to that in the intermolt (anecdysial) epithelium, suggesting that there was a net accumulation of both proteins proportional to the increase in cellular volume. These results support the previous biochemical analyses and, more specifically, localize actin and tubulin in exoskeletal structures, suggesting that they may serve both intracellular and extracellular functions in crustaceans. (C) 2000 Wiley-Liss, Inc. C1 Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA. Oak Ridge Natl Lab, Div Biol, Oak Ridge, TN 37831 USA. E Tennessee State Univ, Dept Anat & Cell Biol, Johnson City, TN 37614 USA. RP Mykles, DL (reprint author), Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA. NR 60 TC 10 Z9 10 U1 1 U2 6 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0022-104X J9 J EXP ZOOL JI J. Exp. Zool. PD MAR 1 PY 2000 VL 286 IS 4 BP 329 EP 342 DI 10.1002/(SICI)1097-010X(20000301)286:4<329::AID-JEZ1>3.0.CO;2-M PG 14 WC Zoology SC Zoology GA 288LD UT WOS:000085563500001 PM 10684556 ER PT J AU Robinson, AL Sextro, RG AF Robinson, AL Sextro, RG TI A novel technique to measure the magnitude and direction of flow in a tube SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID ATMOSPHERIC-PRESSURE FLUCTUATIONS; DRIVEN; ENTRY AB This paper describes a novel in-line sensor that measures the magnitude and direction of gas flow in a tribe. The sensor possesses a unique set of performance characteristics: low detection limit, little resistance to flow: and directional sensitivity. The sensor consists of two hot wire anemometers mounted in a U-shaped tube. Differences in the signals between the two hot wires under low velocity conditions are used to determine the direction of the pow. Calibration curves of flow rate versus measured velocity are used to determine the magnitude of the flow. The sensor has applications in systems that are characterized by naturally driven oscillating flows . [S0098-2202(00)02701-2]. C1 Carnegie Mellon Univ, Dept Mech Engn, Pittsburgh, PA 15213 USA. Carnegie Mellon Univ, Dept Engn & Publ Policy, Pittsburgh, PA 15213 USA. EO Lawrence Berkeley Natl Lab, Div Energy & Environm, Berkeley, CA 94720 USA. RP Robinson, AL (reprint author), Carnegie Mellon Univ, Dept Mech Engn, Pittsburgh, PA 15213 USA. RI Robinson, Allen/I-5713-2012; Robinson, Allen/M-3046-2014 OI Robinson, Allen/0000-0003-1053-7090; Robinson, Allen/0000-0002-1819-083X NR 4 TC 0 Z9 0 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD MAR PY 2000 VL 122 IS 1 BP 186 EP 188 DI 10.1115/1.483249 PG 3 WC Engineering, Mechanical SC Engineering GA 309HL UT WOS:000086762400029 ER PT J AU Gresham, GL Groenewold, GS Bauer, WF Ingram, JC AF Gresham, GL Groenewold, GS Bauer, WF Ingram, JC TI Secondary ion mass spectrometric characterization of nail polishes and paint surfaces SO JOURNAL OF FORENSIC SCIENCES LA English DT Article DE forensic science; paint; nail polish; static secondary ion mass spectrometry ID TRANSFORM INFRARED MICROSCOPY; LEAST-SQUARES METHODS; STATIC SIMS; GAS-CHROMATOGRAPHY; SOIL; IDENTIFICATION; PIGMENTS; FIBERS; MICROSPECTROPHOTOMETRY; SPECTROSCOPY AB A variety of paint and fingernail polish samples, which were visually similar, but had different chemical compositions and formulations, was analyzed using quadrupole static secondary ion mass spectrometry (SIMS). Coating distinction was easily achieved in many cases because of the presence of dominant ions derived from the components of the coating, which could be observed in the SIMS spectra. In other instances, coating distinction was difficult within a product line because of spectral complexity; for this reason and because of the large numbers of spectra generated in this study, multivariate statistical techniques were employed, which allowed the meaningful classification and comparison of spectra. Partial Least Squares (PLS) and Principal Component Analysis (PCA) were applied to quadrupole SIMS data. PCA showed distinct spectral differences between most spectral groups, and also emphasized the reproducibility of the SIMS spectra. When using PLS analysis, reasonably accurate coating identification was achieved with the data. Overall, the PLS model is more than 90% effective in identifying the spectrum of a particular coating, and nearly 100% effective at telling which coating components represented in the PLS models are not present in a spectrum. The level of spectral variation caused by sample bombardment in the SIMS analysis was investigated using Fourier transform infrared spectroscopy (FT-IR) and quadrupole static SIMS. Changes in the FT-IR spectra were observed and were most likely a result of a number of factors involving the static SIMS analysis. However, the bulk of the sample is unaltered and may be used for further testing. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Gresham, GL (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. RI Bauer, William/B-8357-2016 OI Bauer, William/0000-0002-7190-9700 NR 44 TC 14 Z9 14 U1 3 U2 15 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0022-1198 J9 J FORENSIC SCI JI J. Forensic Sci. PD MAR PY 2000 VL 45 IS 2 BP 310 EP 323 PG 14 WC Medicine, Legal SC Legal Medicine GA 298RP UT WOS:000086153200010 PM 10782951 ER PT J AU Grunder, H Berry, L Ellis, W Fonck, R Freidberg, J Gebbie, KB Hawryluk, RJ Montgomery, B Navratil, G Neilson, H Perkins, J Rosen, SL Schoenberg, K Weitzner, H AF Grunder, H Berry, L Ellis, W Fonck, R Freidberg, J Gebbie, KB Hawryluk, RJ Montgomery, B Navratil, G Neilson, H Perkins, J Rosen, SL Schoenberg, K Weitzner, H TI Recommendations on the nature and level of US participation in the International Thermonuclear Experimental Reactor (ITER) extension of the engineering design activities SO JOURNAL OF FUSION ENERGY LA English DT Article DE fusion energy; ITER AB The Department of Energy (DOE) Office of Energy Research chartered through the Fusion Energy Sciences Advisory Committee (FESAC) a panel to "address the topic of U.S. participation in an ITER construction phase, assuming the ITER Parties decide to proceed with construction." Given that there is expected to be a transition period of 3 to 5 years between the conclusion of the Engineering Design Activities (EDA) and the possible construction start, the DOE Office of Energy Research expanded the charge to "include the U.S. role in an interim period between the EDA and construction." This panel has heard presentations and received input from a wide cross-section of parties with an interest in the fusion program. The panel concluded it could best fulfill its responsibility under this charge by considering the fusion energy science and technology portion of the U.S. program in its entirely. Accordingly, the panel is making some recommendations for optimum use of the transition period considering the goals of the fusion program and budget pressures. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Raytheon Engineers & Constructors, New York, NY 10048 USA. Univ Wisconsin, Madison, WI 53706 USA. MIT, Cambridge, MA 02139 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Columbia Univ, New York, NY 10027 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Houston Lighting & Power, Wadsworth, TX 77843 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NYU, Courant Inst Math Sci, New York, NY 10012 USA. RP Grunder, H (reprint author), Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0164-0313 J9 J FUSION ENERG JI J. Fusion Energy PD MAR PY 2000 VL 19 IS 1 BP 35 EP 44 DI 10.1023/A:1012277725912 PG 10 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 490XQ UT WOS:000172079300002 ER PT J AU Harkness, SD Baker, CC Abdou, MA Davis, JW Hogan, W Kulcinski, GL Mauel, M McHargue, C Odette, R Petti, DA Shewmon, P Zweben, SJ AF Harkness, SD Baker, CC Abdou, MA Davis, JW Hogan, W Kulcinski, GL Mauel, M McHargue, C Odette, R Petti, DA Shewmon, P Zweben, SJ TI Review of the fusion materials research program SO JOURNAL OF FUSION ENERGY LA English DT Review DE fusion materials; fusion neutron source AB This report presents the results and recommendations of the deliberations of the U.S. Department of Energy (DOE) Fusion Energy Sciences Advisory Committee Panel on the Review of the Fusion Materials Research Program carried out during 1998. Metrics. evaluated included evidence of recognition, publications per worker, new people attracted to the work and significance of recent accomplishments. C1 Westinghouse Res Labs, Pittsburgh, PA 15235 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Boeing Co, St Louis, MO 63166 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Wisconsin, Madison, WI 53706 USA. Columbia Univ, New York, NY 10027 USA. Univ Tennessee, Knoxville, TN 37996 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Idaho Natl Engn Lab, Idaho Falls, ID 83415 USA. Ohio State Univ, Columbus, OH 43210 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Harkness, SD (reprint author), Westinghouse Res Labs, Pittsburgh, PA 15235 USA. OI Mauel, Michael/0000-0003-2490-7478 NR 9 TC 0 Z9 0 U1 0 U2 3 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0164-0313 J9 J FUSION ENERG JI J. Fusion Energy PD MAR PY 2000 VL 19 IS 1 BP 45 EP 64 DI 10.1023/A:1012229809982 PG 20 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 490XQ UT WOS:000172079300003 ER PT J AU Sauthoff, N Baker, C Baker, D Bengston, R Bloom, E Drake, J Faltens, A Granetz, R Lyon, J Mioduszewski, P Nevins, W Smith, D Ulrickson, M Van Dam, J Wurden, G Young, K AF Sauthoff, N Baker, C Baker, D Bengston, R Bloom, E Drake, J Faltens, A Granetz, R Lyon, J Mioduszewski, P Nevins, W Smith, D Ulrickson, M Van Dam, J Wurden, G Young, K TI Technical opportunities for international collaborations by the US fusion program SO JOURNAL OF FUSION ENERGY LA English DT Article DE fusion energy; international collaboration. AB This report was prepared by a Working Group at the request of the U.S. Department of Energy, Office of Fusion Energy Sciences in 1997. The report addresses technical opportunities for mutually beneficial collaboration between the United States and other international fusion research programs. A number of outstanding opportunities are discussed. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Gen Atom Co, San Diego, CA 92186 USA. Univ Texas, Austin, TX 78712 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Maryland, College Pk, MD 20742 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sauthoff, N (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Wurden, Glen/A-1921-2017 OI Wurden, Glen/0000-0003-2991-1484 NR 0 TC 0 Z9 0 U1 1 U2 2 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0164-0313 J9 J FUSION ENERG JI J. Fusion Energy PD MAR PY 2000 VL 19 IS 1 BP 65 EP 79 DI 10.1023/A:1012281826821 PG 15 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 490XQ UT WOS:000172079300004 ER PT J AU Karlsson, SBP Opgenoorth, HJ Eglitis, P Kauristie, K Syrjasuo, M Pulkkinen, T Lockwood, M Nakamura, R Reeves, G Romanov, S AF Karlsson, SBP Opgenoorth, HJ Eglitis, P Kauristie, K Syrjasuo, M Pulkkinen, T Lockwood, M Nakamura, R Reeves, G Romanov, S TI Solar wind control of magnetospheric energy content: Substorm quenching and multiple onsets SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID NEAR-EARTH MAGNETOTAIL; WESTWARD TRAVELING SURGE; CURRENT WEDGE; NEUTRAL LINE; GROWTH PHASE; IONOSPHERE; MODEL; EXCITATION; CONVECTION; DYNAMICS AB In this paper we report coordinated multispacecraft and ground-based observations of a double substorm onset close to Scandinavia on November 17, 1996. The Wind and the Geotail spacecraft, which were located in the solar wind and the subsolar magnetosheath, respectively, recorded two periods of southward directed interplanetary magnetic field (IMF). These periods were separated by a short northward IMF excursion associated with a solar wind pressure pulse, which compressed the magnetosphere to such a degree that Geotail for a short period was located outside the bow shock. The first period of southward IMF initiated a substorm growth. phase, which was clearly detected by an array of ground-based instrumentation and by Interball in the northern tail lobe. A first substorm onset occurred in close relation to the solar wind pressure pulse impinging on the magnetopause and almost simultaneously with the northward turning of the IMF. However, this substorm did not fully develop. In clear association with the expansion of the magnetosphere at the end of the pressure pulse, the auroral expansion was stopped, and the northern sky cleared. We will present evidence that the change in the solar wind dynamic pressure actively quenched the energy available for any further substorm expansion. Directly after this period, the magnetometer network detected signatures of a renewed substorm growth phase, which was initiated by the second southward turning of the IMF and which finally lead to a second, and this time complete, substorm intensification. We have used our multipoint observations in order to understand the solar wind control of the substorm onset and substorm quenching. The relative timings between the observations on the various satellites and on the ground were used to infer a possible causal relationship between the solar wind pressure variations and consequent substorm development. Furthermore, using a relatively simple algorithm to model the tail lobe field and the total tail flux, we show that there indeed exists a close relationship between the relaxation of a solar wind pressure pulse, the reduction of the tail lobe field, and the quenching of the initial substorm. C1 Swedish Inst Space Phys, Uppsala Div, S-79551 Uppsala, Sweden. Finnish Meteorol Inst, FIN-00101 Helsinki, Finland. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Nagoya Univ, Solar Terr Environm Lab, Toyokawa, Japan. Max Planck Inst Extraterr Phys, D-84740 Garching, Germany. Los Alamos Natl Lab, Los Alamos, NM USA. Russian Acad Sci, Inst Space Res, Moscow 117810, Russia. RP Swedish Inst Space Phys, Uppsala Div, S-79551 Uppsala, Sweden. EM opg@irfu.se RI Syrjasuo, Mikko/E-5088-2012; Lockwood, Mike/G-1030-2011; Nakamura, Rumi/I-7712-2013; Reeves, Geoffrey/E-8101-2011; Pulkkinen, Tuija/D-8403-2012 OI Lockwood, Mike/0000-0002-7397-2172; Nakamura, Rumi/0000-0002-2620-9211; Reeves, Geoffrey/0000-0002-7985-8098; Pulkkinen, Tuija/0000-0002-6317-381X NR 55 TC 6 Z9 6 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 1 PY 2000 VL 105 IS A3 BP 5335 EP 5356 DI 10.1029/1999JA900297 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 288TY UT WOS:000085581600022 ER PT J AU Chang, SW Scudder, JD Fennell, JF Friedel, R Lepping, RP Russell, CT Trattner, KJ Fuselier, SA Peterson, WK Spence, HE AF Chang, SW Scudder, JD Fennell, JF Friedel, R Lepping, RP Russell, CT Trattner, KJ Fuselier, SA Peterson, WK Spence, HE TI Energetic magnetosheath ions connected to the Earth's bow shock: Possible source of cusp energetic ions SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MAGNETIC-FIELD ORIENTATION; PLASMA DEPLETION LAYER; DIFFUSE IONS; SOLAR-WIND; DAYSIDE MAGNETOSHEATH; MAGNETOSPHERIC IONS; SUPRATHERMAL IONS; UPSTREAM; PARTICLE; ACCELERATION AB Plasma and magnetic field data detected by NASA GGS/Polar and Wind during the May 4, 1998, storm event are analyzed to demonstrate for the first time a causal relation between the magnetosheath energetic: ions and bow shock magnetic geometry. Intense magnetosheath energetic ions observed upstream from the cusp are from the quasi-parallel bow shock and show properties indicating that they are a possible source of cusp energetic ions. C1 Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Aerospace Corp, Los Angeles, CA 90009 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Lockheed Martin Adv Technol Ctr, Palo Alto, CA 94304 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. Boston Univ, Dept Astron & Space Phys, Boston, MA 02215 USA. RP Chang, SW (reprint author), Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. RI Friedel, Reiner/D-1410-2012; Scudder, Jack/D-8417-2013; Spence, Harlan/A-1942-2011; Peterson, WK/A-8706-2009; OI Friedel, Reiner/0000-0002-5228-0281; Scudder, Jack/0000-0001-7975-5630; Peterson, WK/0000-0002-1513-6096; Russell, Christopher/0000-0003-1639-8298; Spence, Harlan/0000-0002-2526-2205 NR 50 TC 29 Z9 29 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 1 PY 2000 VL 105 IS A3 BP 5471 EP 5488 DI 10.1029/1999JA900468 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 288TY UT WOS:000085581600034 ER PT J AU Harvey, JA Kachru, S Moore, G Silverstein, E AF Harvey, JA Kachru, S Moore, G Silverstein, E TI Tension is dimension SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE D-branes; conformal field models in string theory ID CONFORMAL-FIELD-THEORY; SU(2) WZW MODELS; D-BRANES; BOUNDARY-CONDITIONS; STRING THEORY; OPERATORS; DUALITY; STATES AB We propose a simple universal formula for the tension of a D-brane in terms of a regularized dimension of the associated conformal field theory statespace. C1 Univ Chicago, Dept Phys, Chicago, IL 60637 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, SLAC, Stanford, CA 94305 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. RP Harvey, JA (reprint author), Rutgers State Univ, Dept Phys & Astron, POB 849, Piscataway, NJ 08855 USA. EM harvey@theory.uchicago.edu; skachru@leland.stanford.edu; moore@castalia.physics.yale.edu; evas@SLAC.Stanford.EDU NR 44 TC 72 Z9 73 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 MAR PY 2000 IS 3 AR 001 PG 16 WC Physics, Particles & Fields SC Physics GA 345FH UT WOS:000088805600001 ER PT J AU Silverstein, E Song, YS AF Silverstein, E Song, YS TI On the critical behavior of D1-brane theories SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE D-branes; brane dynamics in gauge theories; conformal field models in string theory ID CONFORMAL FIELD-THEORIES; CALABI-YAU MANIFOLDS; LARGE N-LIMIT; STRING THEORY; GAUGE-THEORIES; DIMENSIONS; MODEL; EXPANSION; ORBIFOLDS; DYNAMICS AB We study renormalization-group ow patterns in theories arising on D1-branes in various supersymmetry-breaking backgrounds. We argue that the theory of N D1-branes transverse to an orbifold space can be fine-tuned to ow to the corresponding orbifold conformal field theory in the infrared, for particular values of the couplings and theta angles which we determine using the discrete symmetries of the model. By calculating various nonplanar contributions to the scalar potential in the worldvolume theory, we show that fine-tuning is in fact required at finite N, as would be generically expected. We further comment on the presence of singular conformal field theories (such as those whose target space includes a "throat" described by an exactly solvable CFT) in the non-supersymmetric context. Throughout the analysis two applications are considered: to gauge theory/gravity duality and to linear sigma model techniques for studying worldsheet string theory. C1 Inst Adv Study, Sch Nat Sci, Princeton, NJ 08540 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94305 USA. RP Silverstein, E (reprint author), Inst Adv Study, Sch Nat Sci, Olden Lane, Princeton, NJ 08540 USA. EM evas@slac.stanford.edu; yss@leland.stanford.edu NR 44 TC 4 Z9 4 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 MAR PY 2000 IS 3 AR 029 PG 21 WC Physics, Particles & Fields SC Physics GA 345FH UT WOS:000088805600029 ER PT J AU Kasunic, KJ AF Kasunic, KJ TI Design equations for the reflectivity of deep-etch distributed Bragg reflector gratings SO JOURNAL OF LIGHTWAVE TECHNOLOGY LA English DT Article DE distributed Bragg reflector (DBR) lasers; gratings; numerical modeling; optical diffraction; optical reflection; optical waveguide components; optoelectronic devices; semiconductor lasers ID EDGE-EMITTING LASERS; PHOTONIC MICROSTRUCTURES; MIRRORS AB This paper reports a computationally efficient, grid-independent method for calculating the reflectivity of deep-etch distributed Bragg reflector (DBR) gratings. The method employs Gaussian beam propagation in conjunction with a Fabry-Perot model that includes the effects of multiple reflections in multiple cavities, We include both grating pitch and number of Bragg pairs in our analysis. We obtain very good agreement with results generated by a Helmholtz equation solver. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Kasunic, KJ (reprint author), Univ Arizona, Dept Math, Tucson, AZ 85721 USA. NR 13 TC 15 Z9 16 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0733-8724 J9 J LIGHTWAVE TECHNOL JI J. Lightwave Technol. PD MAR PY 2000 VL 18 IS 3 BP 425 EP 429 DI 10.1109/50.827516 PG 5 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA 299NP UT WOS:000086205000020 ER PT J AU Keating, KA Myers, JD Pelton, JG Bair, RA Wemmer, DE Ellis, PD AF Keating, KA Myers, JD Pelton, JG Bair, RA Wemmer, DE Ellis, PD TI Development and use of a virtual NMR facility SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article DE collaboratory; collaboratorium; virtual NMR facility; electronic notebook; TeleViewer ID SHOCK TRANSCRIPTION FACTOR; DNA-BINDING DOMAIN; SPECTROSCOPY AB We have developed a "virtual NMR facility" (VNMRF) to enhance access to the NMR spectrometers in Pacific Northwest National Laboratory's Environmental Molecular Sciences Laboratory (EMSL). We use the term virtual facility to describe a real NMR facility made accessible via the Internet. The VNMRF combines secure remote operation of the EMSL's NMR spectrometers over the Internet with real-time videoconferencing, remotely controlled laboratory cameras, real-time computer display sharing, a Web-based electronic laboratory notebook, and other capabilities. Remote VNMRF users can see and converse with EMSL researchers, directly and securely control the EMSL spectrometers, and collaboratively analyze results. A customized Electronic Laboratory Notebook allows interactive Web-based access to group notes, experimental parameters, proposed molecular structures, and other aspects of a research project. This paper describes our experience developing a VNMRF and details the specific capabilities available through the EMSL VNMRF, We show how the VNMRF has evolved during a test project and present an evaluation of its impact in the EMSL and its potential as a model for other scientific facilities. All Collaboratory software used in the VNMRF is freely available from www.emsl.pnl.gov:2080/ docs/collab. (C) 2000 Academic press. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Myers, JD (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. OI Myers, James/0000-0001-8462-650X NR 14 TC 7 Z9 7 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD MAR PY 2000 VL 143 IS 1 BP 172 EP 183 DI 10.1006/jmre.1999.1974 PG 12 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 294MG UT WOS:000085914600019 PM 10698658 ER PT J AU Wind, RA Bai, S Hu, JZ Solum, MS Ellis, PD Grant, DM Pugmire, RJ Taylor, CMV Yonker, CR AF Wind, RA Bai, S Hu, JZ Solum, MS Ellis, PD Grant, DM Pugmire, RJ Taylor, CMV Yonker, CR TI H-1 dynamic nuclear polarization in supercritical ethylene at 1.4 T SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article DE DNP; Overhauser effect; supercritical fluids; ethylene ID AQUEOUS CHAR SUSPENSIONS; C-13 NMR-SPECTROSCOPY; LOW MAGNETIC-FIELD; SOLIDS; TEMPERATURE; FLUIDS; DNP AB H-1 dynamic nuclear polarization (DNP) has been measured in supercritical ethylene in the pressure range 60-300 bar in an external field of 1.4 T. A single-cell sapphire tube was used as a high-pressure cell, and powdered 1,3-bisdiphenylene-2-phenyl allyl (BDPA) free radicals were added and distributed at the wall of the cell. At all pressures the dominant DNP mechanism was a positive Overhauser enhancement, caused by proton-electron contact interactions at the fluid/solid radical interface. The observed enhancements varied from 12 at 60 bar to 17 at 300 bar. Besides the Overhauser enhancement, small solid state and thermal mixing enhancements also were observed, indicating that part of the ethylene was adsorbed at the radical surface for a prolonged time. The impacts of the experimental conditions on the Overhauser enhancement factors are discussed, and enhancements of at least 40-60 are estimated when the EPR saturation factor and the leakage factor become maximal. These data indicate that DNP-enhanced NMR has the potential of extending the impact of NMR in research areas involving supercritical fluids. (C) 2000 Academic Press. C1 Pacific NW Lab, Richland, WA 99352 USA. Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA. Univ Utah, Dept Chem & Fuels Engn, Salt Lake City, UT 84112 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Wind, RA (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. RI Hu, Jian Zhi/F-7126-2012 NR 36 TC 7 Z9 7 U1 0 U2 13 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD MAR PY 2000 VL 143 IS 1 BP 233 EP 239 DI 10.1006/jmre.2000.2016 PG 7 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 294MG UT WOS:000085914600027 PM 10698666 ER PT J AU Morrell, JS Xue, ZB Specht, ED Goyal, A Martin, PM Lee, DF Feenstra, R Verebelyi, DT Christen, DK Chirayil, TG Paranthaman, M Vallet, CE Beach, DB AF Morrell, JS Xue, ZB Specht, ED Goyal, A Martin, PM Lee, DF Feenstra, R Verebelyi, DT Christen, DK Chirayil, TG Paranthaman, M Vallet, CE Beach, DB TI Epitaxial growth of gadolinium oxide on roll-textured nickel using a solution growth technique SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID CRITICAL-CURRENT DENSITY; SUPERCONDUCTING TAPES; ALUMINATE FILMS; BUFFER LAYERS; YBA2CU3O7 AB Chemical solution epitaxy was used to deposit an epitaxial film of Gd2O3 on roll-textured nickel. A 2-methoxyethanol solution of gadolinium methoxyethoxide was used for spin-coating and dip-coating. Films were crystallized using a heat treatment at 1160 degrees C for 1 h in 4% H-2/96% Ar. Single-layer films were approximately 600 Angstrom in thickness, and thicker films could be produced using multiple coatings. theta/2 theta x-ray diffractograms revealed only (0041) reflections, indicating a high degree of out-of-plane texture. A pole-figure about the Gd2O3 (222) reflection indicated a single in-plane epitaxy. Scanning electron microscopy showed that the films were smooth, continuous, and free of pin holes. Atomic force microscopy revealed an average surface roughness of 53 Angstrom. Electron diffraction indicated that the misalignment of the majority of the grains in the plane was less than 10 degrees. High-current (0.4 MA/cm(2)) YBa2Cu3O7-delta films were grown on roll-textured nickel substrates using Gd2O3 as the base layer in a three-layer buffer structure. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RP Beach, DB (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, 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 15 TC 25 Z9 27 U1 0 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAR PY 2000 VL 15 IS 3 BP 621 EP 628 DI 10.1557/JMR.2000.0092 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 290VK UT WOS:000085698400007 ER PT J AU Zeuch, DH Montgomery, ST Holcomb, DJ AF Zeuch, DH Montgomery, ST Holcomb, DJ TI Uniaxial compression experiments on lead zirconate titanate 95/5-2Nb ceramic: Evidence for an orientation-dependent, "maximum compressive stress" criterion for onset of the ferroelectric to antiferroelectric polymorphic transformation SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID PHASE-TRANSFORMATION AB Recently we showed that, under nonhydrostatic loading, the F-R1 --> A(O) polymorphic transformation of unpoled lead zirconate titanate 95/5-2Nb (PNZT) ceramic began when the maximum compressive stress equaled the hydrostatic pressure at which the transformation otherwise occurred. More recently we showed that this criterion seemed not to apply to poled ceramic. However, unpoled ceramic is isotropic whereas poled ceramic is not. If we further assume that the transformation depends on both the stress magnitude and its orientation relative to PNZT's structure, these disparate results can be resolved. This modified hypothesis makes two predictions for transformation of unpoled ceramic under uniaxial compression: (i) it will begin when the compressive stress equals the hydrostatic pressure for transformation, and (ii) steadily increasing stress will be required to drive it to completion. Here we present experimental results that confirm these predictions. We then revisit our earlier results for poled and unpoled PNZT, The new hypothesis quantifies the observed effect of shear stress on the mean stress for onset of the transformation of unpoled ceramic and explains previously reported kinetic effects. C1 Sandia Natl Labs, Geomech Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Integrated Prod Dev Dept, Albuquerque, NM 87185 USA. RP Zeuch, DH (reprint author), Sandia Natl Labs, Geomech Dept, POB 5800-0751, Albuquerque, NM 87185 USA. NR 23 TC 18 Z9 19 U1 2 U2 8 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAR PY 2000 VL 15 IS 3 BP 689 EP 703 DI 10.1557/JMR.2000.0102 PG 15 WC Materials Science, Multidisciplinary SC Materials Science GA 290VK UT WOS:000085698400017 ER PT J AU Lenggoro, IW Hata, T Iskandar, F Lunden, MM Okuyama, K AF Lenggoro, IW Hata, T Iskandar, F Lunden, MM Okuyama, K TI An experimental and modeling investigation of particle production by spray pyrolysis using a laminar flow aerosol reactor SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID EVAPORATION AB The influence of operating parameters on the morphology of particles prepared by spray pyrolysis was investigated using a temperature-graded laminar flow aerosol reactor. Experimentally, zirconia particles were prepared by spray pyrolysis using an aqueous solution of zirconyl hydroxide chloride. Hollow particles were formed if the reactor temperature was high, the temperature gradient was too large, the flow rate of carrier gas was high, and the initial solute concentration was low. A numerical simulation of the pyrolysis process was developed using a combination of two previous models. The simulation results compared well with the experimental results. C1 Hiroshima Univ, Dept Chem Engn, Higashihiroshima 7398527, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Okuyama, K (reprint author), Hiroshima Univ, Dept Chem Engn, Kagamiyama 1-4-1, Higashihiroshima 7398527, Japan. RI Lenggoro, Wuled/B-8629-2009; Iskandar, Ferry/A-6696-2009; okuyama, kikuo/F-6092-2010 OI Lenggoro, Wuled/0000-0002-0048-8486; Iskandar, Ferry/0000-0002-0464-0035; NR 18 TC 101 Z9 102 U1 1 U2 9 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAR PY 2000 VL 15 IS 3 BP 733 EP 743 DI 10.1557/JMR.2000.0106 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA 290VK UT WOS:000085698400021 ER PT J AU Misra, A Kung, H Mitchell, TE Nastasi, M AF Misra, A Kung, H Mitchell, TE Nastasi, M TI Residual stresses in polycrystalline Cu/Cr multilayered thin films SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID MECHANICAL-PROPERTIES; INTERFACE STRESSES; MOLECULAR-DYNAMICS; INTRINSIC STRESS; VAPOR-DEPOSITION; MICROSTRUCTURE; COPPER AB Residual stresses in sputter-deposited Cu/Cr multilayers and Cu and Cr single-layered polycrystalline thin films were evaluated by the substrate curvature method. The stresses in the multilayers were found to be tensile and to increase in magnitude with increasing layer thickness (h) to a peak value of similar to 1 GPa for h = 50 nm. For h > 50 nm, the residual stress decreased with increasing h but remained tensile. The same trends were observed in single-layered Cu and Cr thin films, except that the maximum stress in Cu films is 1 order of magnitude lower than that in Cr. Transmission electron microscopy was used to study the rnicrostructural evolution as a function of layer thickness. The evolution of tensile growth stresses in Cr films is explained by island coalescence and subsequent growth with increasing thickness. Estimates of the Cr Film yield strength indicated that, for h greater than or equal to 50 nm, the residual stress may be limited by the yield strength. Substrate curvature measurements on bilayer films of different thicknesses were used to demonstrate that a non-negligible contribution to the total stress in the multilayers arises from the interface stress. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Misra, A (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RI Misra, Amit/H-1087-2012 NR 32 TC 21 Z9 21 U1 0 U2 10 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAR PY 2000 VL 15 IS 3 BP 756 EP 763 DI 10.1557/JMR.2000.0109 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 290VK UT WOS:000085698400024 ER PT J AU Wang, JG Choi, BW Nieh, TG Liu, CT AF Wang, JG Choi, BW Nieh, TG Liu, CT TI Crystallization and nanoindentation behavior of a bulk Zr-Al-Ti-Cu-Ni amorphous alloy SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID SUPERCOOLED LIQUID REGION; MECHANICAL-PROPERTIES; METALLIC-GLASS; TRANSITION; ZR41.2TI13.8CU12.5NI10.0BE22.5; PRECIPITATION; PARTICLES; DENSITY; OXYGEN; PHASE AB The crystallization and nanoindentation behavior of a Zr-10Al-STi-17.9Cu-14.6Ni (at.%) bulk amorphous alloy (BAA) were studied. Resulting from the kinetic nature of phase transformation in multicomponent alloys, the crystallization path is complex. Despite the complexity of different crystallization paths, the main final crystallized product in the Zr-based BAA is Zr2Cu. Young's modulus and hardness of the BAA were found to increase with an increase in annealing temperature. The observed mechanical properties were correlated with the microstructure of the material. Also, in the present paper, both the observed crystallization and nanoindentation behavior are compared with existing data. Zr-based BAAs exhibit a ratio of hardness to Young's modulus (H/E ratio) of about 1/10, suggesting the interatomic bonding in the alloys is close to being covalent. C1 Univ Calif Irvine, Dept Chem & Biochem Engn & Mat Sci, Irvine, CA 92697 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Wang, JG (reprint author), Univ Calif Irvine, Dept Chem & Biochem Engn & Mat Sci, Irvine, CA 92697 USA. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 32 TC 102 Z9 105 U1 1 U2 26 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAR PY 2000 VL 15 IS 3 BP 798 EP 807 DI 10.1557/JMR.2000.0114 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 290VK UT WOS:000085698400029 ER PT J AU Xu, HW Navrotsky, A Nyman, MD Nenoff, TM AF Xu, HW Navrotsky, A Nyman, MD Nenoff, TM TI Thermochemistry of microporous silicotitanate phases in the Na2O-Cs2O-SiO2-TiO2-H2O system SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID SODIUM TITANIUM SILICATE; ION-EXCHANGE PROPERTIES; PHARMACOSIDERITE ANALOG; POROUS TITANOSILICATE; CRYSTAL-STRUCTURES; CALORIMETRY; FRAMEWORKS; STABILITY AB Microporous silicotitanates can potentially be used as ion exchangers for removal of Cs+ from radioactive waste solutions. The enthalpies of formation from constituent oxides for two series of silicotitanates at 298 K have been determined by drop-solution calorimetry into molten 2PbO . B2O3 at 974 K: the (Na1-xCsx)(3)Ti4Si3O15(OH). nH(2)O (n = 4 to 5) phases with a cubic structure (P (4) over bar 3m), and the (Na1-xCsx)(3)Ti4Si2O13(OH). nH(2)O (n = 4 to 5) phases with a tetragonal structure (P4(2)/mcm). The enthalpies of formation from the oxides for the cubic series become more exothermic as Cs/(Na + Cs) increases, whereas those for the tetragonal series become less exothermic. This result indicates that the incorporation of Cs in the cubic phase is somewhat thermodynamically favorable, whereas that in the tetragonal phase is thermodynamically unfavorable and kinetically driven. In addition, the cubic phases are more stable than the corresponding tetragonal phases with the same Cs/Na ratios. These disparities in the energetic behavior between the two series are attributed to their differences in both local bonding configuration and degree of hydration. C1 Univ Calif Davis, Dept Chem Engn & Mat Sci, Thermochem Facil, Davis, CA 95616 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Xu, HW (reprint author), Univ Calif Davis, Dept Chem Engn & Mat Sci, Thermochem Facil, Davis, CA 95616 USA. NR 28 TC 19 Z9 20 U1 1 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAR PY 2000 VL 15 IS 3 BP 815 EP 823 DI 10.1557/JMR.2000.0116 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA 290VK UT WOS:000085698400031 ER PT J AU Percus, JK Percus, OE Perelson, AS AF Percus, JK Percus, OE Perelson, AS TI Random binding of dimers to chains SO JOURNAL OF MATHEMATICAL BIOLOGY LA English DT Article DE dimers; binding; probability theory; MHC ID PEPTIDES AB We develop a probabilistic model for the binding of a small linear polymer to a larger chain. We assume that we can approximate the energy of interaction of the two chains by summing the pairwise interactions between subunits. Because the energy of interaction between a pair of subunits can depend on neighboring subunits, which we assume vary along the chain, we assign the pairwise energies of interactions according to a specified probability distribution. Thus we develop a statistical model for the binding of two molecules. While such models may not be appropriate for studying the interaction of a particular pair of molecules, they can provide insight into quest-ions that deal with populations of molecules, such as why do MHC molecules bind peptides of a certain size? Here we analyze in detail the special case of a heterodimer binding to a polymer. C1 Univ Calif Los Alamos Natl Lab, Grp T 10, Los Alamos, NM 87545 USA. NYU, Courant Inst Math Sci, New York, NY 10012 USA. RP Perelson, AS (reprint author), Univ Calif Los Alamos Natl Lab, Grp T 10, Mail Stop K7190,POB 1663, Los Alamos, NM 87545 USA. FU NIAID NIH HHS [AI28433] NR 11 TC 1 Z9 1 U1 1 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0303-6812 J9 J MATH BIOL JI J. Math. Biol. PD MAR PY 2000 VL 40 IS 3 BP 278 EP 294 DI 10.1007/s002850050181 PG 17 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA 304CG UT WOS:000086464600004 PM 10794438 ER PT J AU Chang, YJ Stephen, JR Richter, AP Venosa, AD Bruggemann, J Macnaughton, SJ Kowalchuk, GA Haines, JR Kline, E White, DC AF Chang, YJ Stephen, JR Richter, AP Venosa, AD Bruggemann, J Macnaughton, SJ Kowalchuk, GA Haines, JR Kline, E White, DC TI Phylogenetic analysis of aerobic freshwater and marine enrichment cultures efficient in hydrocarbon degradation: effect of profiling method SO JOURNAL OF MICROBIOLOGICAL METHODS LA English DT Article DE enrichment cultures; DGGE; hydrocarbon degradation; polymerase chain reaction; phylogenetic analysis; 16S rDNA ID 16S RIBOSOMAL-RNA; GRADIENT GEL-ELECTROPHORESIS; DEGRADING BACTERIA; MICROBIAL-POPULATIONS; GENUS SPHINGOMONAS; ACTIVATED-SLUDGE; ECOLOGY; DIVERSITY; DATABASE; PROBES AB Aerobically grown enrichment cultures derived from hydrocarbon-contaminated seawater and freshwater sediments were generated by growth on crude oil as sole carbon source. Both cultures displayed a high rate of degradation for a wide range of hydrocarbon compounds. The bacterial species composition of these cultures was investigated by PCR of the 16S rDNA gene using multiple primer combinations. Near full-length 16S rDNA clone libraries were generated and screened by restriction analysis prior to sequence analysis. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was carried out using two other PCR primer sets targeting either the V3 or V6-V8 regions, and sequences derived from prominent DGGE bands were compared to sequences obtained via cloning. All data sets suggested that the seawater culture was dominated by alpha-subgroup proteobacteria, whereas the freshwater culture was dominated by members of the beta- and gamma-proteobacteria. However, the V6-V8 primer pair was deficient in the recovery of Sphingomonas-like 16S rDNA due to a 3' terminal mismatch with the reverse primer. Most 16S rDNA sequences recovered from the marine enrichment were not closely related to genera containing known oil-degrading organisms, although some were detected. All methods suggested that the freshwater enrichment was dominated by genera containing known hydrocarbon-degrading species. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37932 USA. US EPA, Cincinnati, OH 45268 USA. Netherlands Inst Ecol, NL-6666 ZG Heteren, Netherlands. Oak Ridge Natl Lab, Div Biol Sci, Oak Ridge, TN 37831 USA. RP Stephen, JR (reprint author), Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37932 USA. RI Kowalchuk, George/C-4298-2011 NR 44 TC 60 Z9 72 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-7012 J9 J MICROBIOL METH JI J. Microbiol. Methods PD MAR PY 2000 VL 40 IS 1 BP 19 EP 31 DI 10.1016/S0167-7012(99)00134-7 PG 13 WC Biochemical Research Methods; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA 293HD UT WOS:000085845300003 PM 10739339 ER PT J AU Godfrey, A Lassen, NCK AF Godfrey, A Lassen, NCK TI Unsupervised approval criteria for automated EBSP investigation of deformed metals SO JOURNAL OF MICROSCOPY-OXFORD LA English DT Article DE Al; BKD; calibration; deformation; EBSP; rolling ID ALUMINUM SINGLE-CRYSTAL; DEFORMATION STRUCTURES; LOCAL CRYSTALLOGRAPHY; SLIP PATTERN; MICROSTRUCTURE; ORIENTATIONS; EVOLUTION AB Unsupervised approval criteria have been investigated for orientations gathered from cold deformed samples (medium to high strain range) using the electron backscattering pattern technique. For such samples, the dislocation cell-size is on the order of the available step-size and pattern quality is generally low. Approval criteria for assessing the validity of measured orientations under these conditions were determined using, as a calibration, channel die cold deformed single crystals of stable orientations. In all cases, approval criteria based on an indexing confidence measure are found to be preferable. Different criteria are suggested, depending on whether the orientation data are subsequently to be used for texture analysis, or for a misorientation angle-based analysis. The latter is illustrated by an investigation of the number of deformation generated high angle boundaries introduced during a 90% cold reduction of a polycrystalline sample. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Riso Natl Lab, Dept Mat, DK-4000 Roskilde, Denmark. RP Godfrey, A (reprint author), Holly Cottage, Walk, Wootton By Woodstock OX20 1ED, Oxon, England. RI Godfrey, Andrew/G-4458-2010 OI Godfrey, Andrew/0000-0002-5496-0424 NR 16 TC 1 Z9 1 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-2720 J9 J MICROSC-OXFORD JI J. Microsc.-Oxf. PD MAR PY 2000 VL 197 BP 249 EP 259 PN 3 PG 11 WC Microscopy SC Microscopy GA 295BY UT WOS:000085947200004 ER PT J AU Tan, HS Espenson, JH AF Tan, HS Espenson, JH TI Regioselective oxidative cyclization of hydroxyalkenes to tetrahydrofurans catalyzed by methyltrioxorhenium SO JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL LA English DT Article DE catalysis; rhenium; hydroxyalkene; peroxide; oxidation ID METHYLRHENIUM TRIOXIDE; HYDROGEN-PEROXIDE; RHENIUM OXIDE; GAMMA-LACTONES; EPOXIDATION; OXO; 5-HYDROXYALKENES; MECHANISM; COMPLEXES; KINETICS AB The oxidation of 5-hydroxyalkenes by hydrogen peroxide, when catalyzed by CH3ReO3 (MTO), leads to functionalized tetrahydrofurans. In these cases, no tetrahydropyran was formed. The results show that the first reaction between the substrate and a peroxorhenium species formed from, and in equilibrium with, MTO and peroxide, yields an epoxide. This intermediate was not detected, however, because cyclization occurred so rapidly. 6-Hydroxyalkenes were similarly but more slowly converted to tetrahydropyran alcohols. A 4-hydroxyalkene was epoxidized but not cyclized. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Espenson, JH (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 46 TC 11 Z9 11 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1381-1169 J9 J MOL CATAL A-CHEM JI J. Mol. Catal. A-Chem. PD MAR 1 PY 2000 VL 152 IS 1-2 BP 83 EP 89 DI 10.1016/S1381-1169(99)00294-0 PG 7 WC Chemistry, Physical SC Chemistry GA 292PX UT WOS:000085805200009 ER PT J AU Tuan, VD Griffin, GD Alarie, JP Cullum, B Sumpter, B Noid, D AF Tuan Vo-Dinh Griffin, Guy D. Alarie, Jean Pierre Cullum, Brian Sumpter, Bobby Noid, Donald TI Development of nanosensors and bioprobes SO JOURNAL OF NANOPARTICLE RESEARCH LA English DT Article DE nanosensor; nanoprobe; nanotechnology; biosensor; antibody; benzopyrene tetrol; cyclodextrin; cancer AB We describe the development and application of nanosensors having bioreceptor probes for bioanalysis. The nanoprobes were fabricated with optical fibers pulled downto tips having distal end sizes of approximately 30-60 nm. The use of two different types of receptors was investigated. Fiberoptic nanoprobes were covalently bound either with bioreceptors, such as antibodies, or with other receptors, such as cyclodextrins that are selective for the size and chemical structure of the analyte molecules. Theoretical calculations were performed to model the binding of beta-cyclodextrin with pyrene and 5,6-benzoquinoline, and to illustrate the possibility of comparing experimental data with theoretical data. The antibody-based nanoprobe was used for in situ measurements of benzopyrene tetrol in single cells. The performance of the nanosensor is illustrated by intracellular measurements performed on a rat liver epithelial cell line (Clone 9) used as the model cell system. The usefulness and potential of these nanotechnology-based biosensors in biological research and applications are discussed. C1 [Tuan Vo-Dinh; Griffin, Guy D.; Alarie, Jean Pierre; Cullum, Brian; Sumpter, Bobby; Noid, Donald] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Tuan, VD (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. EM tvo@ornl.gov RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 FU LDRD; Office of Biological and Environmental Research, U.S. Department of Energy [DE-AC05-960R22464] FX This research is sponsored by the LDRD Project (Advanced Nanosensors), and by the Office of Biological and Environmental Research, U.S. Department of Energy under contract DE-AC05-960R22464 with Lockheed Martin Energy Research Corporation. Some of the STM measurements of the fiberoptic nanoprobes were performed by Sutter Instruments. NR 19 TC 26 Z9 26 U1 1 U2 8 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 1388-0764 J9 J NANOPART RES JI J. Nanopart. Res. PD MAR PY 2000 VL 2 IS 1 BP 17 EP 27 DI 10.1023/A:1010005908586 PG 11 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA V19IW UT WOS:000208067100004 ER PT J AU Pui, DYH Brock, JR Chen, DR Fissan, H Frisbie, CD Lyman, CE Miller, JC Mulholland, GW Pecora, R Preining, O Vo-Dinh, T AF Pui, D. Y. H. Brock, J. R. Chen, D-R. Fissan, H. Frisbie, C. D. Lyman, C. E. Miller, J. C. Mulholland, G. W. Pecora, R. Preining, O. Vo-Dinh, T. TI Instrumentation and measurement issues for nanometer particles: Workshop summary SO JOURNAL OF NANOPARTICLE RESEARCH LA English DT Article DE nanoparticles; measurements; instrumentation; standards; aerosols; colloids C1 [Pui, D. Y. H.; Chen, D-R.] Univ Minnesota, Dept Mech Engn, Particle Technol Lab, Minneapolis, MN 55455 USA. [Fissan, H.] Univ Duisburg, Dept Elect Engn, Duisburg, Germany. [Brock, J. R.] Univ Texas Austin, Dept Chem Engn, Austin, TX 78712 USA. [Frisbie, C. D.] Univ Minnesota, Dept Chem Engn, Minneapolis, MN 55455 USA. [Lyman, C. E.] Lehigh Univ, Dept Mat Sci & Engn, Bethlehem, PA 18015 USA. [Miller, J. C.] Oak Ridge Natl Lab, Biochem & Biophys Sect, Oak Ridge, TN 37831 USA. [Mulholland, G. W.] NIST, Bldg & Fire Res Lab, Gaithersburg, MD 20899 USA. [Pecora, R.] Stanford Univ, Dept Chem, Stanford, CA 94305 USA. [Preining, O.] Austrian Acad Sci, Clean Air Commiss, A-1010 Vienna, Austria. [Vo-Dinh, T.] Oak Ridge Natl Lab, Adv Monitoring Dev Grp, Oak Ridge, TN USA. RP Pui, DYH (reprint author), Univ Minnesota, Dept Mech Engn, Particle Technol Lab, 111 Church St SE, Minneapolis, MN 55455 USA. EM dyhpui@maroon.tc.umn.edu RI Frisbie, C Daniel/F-3995-2011 FU office of Basic Energy Sciences at the Department of Energy, through the Council on Energy Engineering Research (CEER) FX This work was supported by the Engineering Research Program of the office of Basic Energy Sciences at the Department of Energy, through the Council on Energy Engineering Research (CEER). The authors thank Dr. Bob Price for his active participation and encouragement. NR 9 TC 7 Z9 7 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 1388-0764 J9 J NANOPART RES JI J. Nanopart. Res. PD MAR PY 2000 VL 2 IS 1 BP 103 EP 112 DI 10.1023/A:1010025905861 PG 10 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA V19IW UT WOS:000208067100012 ER PT J AU Wiench, JW Pruski, M Tischendorf, B Otaigbe, JU Sales, BC AF Wiench, JW Pruski, M Tischendorf, B Otaigbe, JU Sales, BC TI Structural studies of zinc polyphosphate glasses by nuclear magnetic resonance SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 15th University Conference on Glass Science CY JUN 20-23, 1999 CL UNIV MISSOURI ROLLA, ROLLA, MISSOURI SP Univ Missouri Rolla HO UNIV MISSOURI ROLLA ID SHORT-RANGE STRUCTURE; NMR CHEMICAL-SHIFTS; X-RAY-DIFFRACTION; PHOSPHATE-GLASSES; P-31 NMR; MAGIC-ANGLE; SPECTROSCOPY; COORDINATION; SOLIDS AB Nuclear magnetic resonance (NMR) spectroscopy of solids and of liquids was used to study the structure of xZnO + (1 - x)P2O5 glasses prepared from a glass melt in the composition range 0.35 less than or equal to x less than or equal to 0.70. Relative concentrations of Q(n) units in the solid glasses have been compared with the liquid NMR spectra and with the predictions based on the reorganization theory. Disproportionation reactions in glass liquids of meta- and pyrophosphates are evident. Anisotropies of chemical shift tensor for all phosphorus units are given. Structural changes associated with CSA parameters, including the presence of rings and chains are discussed. Both solid and liquid state NMR spectra show that ultraphosphate glasses consist mainly of ring structures, while only chains are present in metaphosphates. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Pruski, M (reprint author), Iowa State Univ, Ames Lab, 230 Spedding Hall, Ames, IA 50011 USA. NR 35 TC 35 Z9 35 U1 0 U2 11 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 MAR PY 2000 VL 263 IS 1-4 BP 101 EP 110 DI 10.1016/S0022-3093(99)00671-7 PG 10 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 290AQ UT WOS:000085654500009 ER PT J AU Marasinghe, GK Karabulut, M Ray, CS Day, DE Shuh, DK Allen, PG Saboungi, ML Grimsditch, M Haeffner, D AF Marasinghe, GK Karabulut, M Ray, CS Day, DE Shuh, DK Allen, PG Saboungi, ML Grimsditch, M Haeffner, D TI Properties and structure of vitrified iron phosphate nuclear wasteforms SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 15th University Conference on Glass Science CY JUN 20-23, 1999 CL UNIV MISSOURI ROLLA, ROLLA, MISSOURI SP Univ Missouri Rolla HO UNIV MISSOURI ROLLA ID GLASSES; SPECTROSCOPY AB The structure of vitreous iron phosphates containing up to 35 wt% of one or more common nuclear waste components such as Na2O Cs2O, SrO, UO2 or Bi2O3 have been investigated using Fe-57 Mossbauer, X-ray absorption, X-ray photoelectron and Raman spectroscopies and high energy X-ray and neutron diffraction techniques. The glass samples investigated were prepared by melting appropriate chemicals in air at approximately 1200 degrees C for 2 h in alumina crucibles. The chemical durability of the glasses was investigated by measuring their dissolution rates in distilled water st 90 degrees C using the product consistency test (PCT) methodology. The chemical durability of these glasses is characterized by dissolution rates of 10-(10)-10-(11) g/cm(2)/min. The Mossbauer spectra indicate the presence of both Fe(II) and Fe(III). However, the maximum Fe(II) fraction, Fe(II)/[Fe(II)+ Fe(III)]. was 0.34. X-ray absorption data show that, on average, both species of iron ions are coordinated with approximately 5 near neighbor oxygens and that the iron-oxygen coordination is only slightly (<10%) influenced by the type or the concentration of the waste elements. Iron ions are also coordinated with 4-6 phosphorous ions in the second shell. Only a minority of the oxygen ions, about 22%, take part in bridging -P-O-P- bonds. Raman spectra show that the phosphorous-oxygen network, which is dominated by (P2O7)(4-) dimer units, in different samples are similar. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Missouri, Dept Phys, Dept Ceram Engn, Rolla, MO 65409 USA. Univ Missouri, Grad Ctr Mat Res, Rolla, MO 65409 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Marasinghe, GK (reprint author), Univ Missouri, Dept Phys, Dept Ceram Engn, 301 Straumanis Hall, Rolla, MO 65409 USA. RI Saboungi, Marie-Louise/C-5920-2013 OI Saboungi, Marie-Louise/0000-0002-0607-4815 NR 19 TC 73 Z9 79 U1 1 U2 12 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 MAR PY 2000 VL 263 IS 1-4 BP 146 EP 154 DI 10.1016/S0022-3093(99)00631-6 PG 9 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 290AQ UT WOS:000085654500015 ER PT J AU Sales, BC Boatner, LA Ramey, JO AF Sales, BC Boatner, LA Ramey, JO TI Chromatographic studies of the structures of amorphous phosphates: a review SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 15th University Conference on Glass Science CY JUN 20-23, 1999 CL UNIV MISSOURI ROLLA, ROLLA, MISSOURI SP Univ Missouri Rolla HO UNIV MISSOURI ROLLA ID FLOW-INJECTION ANALYSIS; LEAD PYROPHOSPHATE; GLASS STATE; CRYSTALLINE; DAMAGE AB The technique of high-performance liquid chromatography (HPLC) has been used to investigate the distribution of phosphate anions in a variety of amorphous phosphate solids. In many cases, HPLC can be used to quantitatively measure the type and distribution of phosphate tetrahedral chains and rings in the solid that are between 1 and 10 nm in size. The experimental details of the HPLC technique are presented and the strengths and limitations of the technique are reviewed. The structural information obtained using HPLC is compared with structural information obtained using solid state techniques such as NMR and XPS. Several specific examples that illustrate the power and sensitivity of the HPLC technique are reviewed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Sales, BC (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008,MS 6056,Bldg 3150, Oak Ridge, TN 37831 USA. RI Boatner, Lynn/I-6428-2013 OI Boatner, Lynn/0000-0002-0235-7594 NR 46 TC 26 Z9 26 U1 0 U2 7 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 MAR PY 2000 VL 263 IS 1-4 BP 155 EP 166 DI 10.1016/S0022-3093(99)00644-4 PG 12 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 290AQ UT WOS:000085654500016 ER PT J AU Jiang, JJ Cygan, RT Alam, TM AF Jiang, JJ Cygan, RT Alam, TM TI Molecular dynamics simulation of the structure and properties of lithium phosphate glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 15th University Conference on Glass Science CY JUN 20-23, 1999 CL UNIV MISSOURI ROLLA, ROLLA, MISSOURI SP Univ Missouri Rolla HO UNIV MISSOURI ROLLA ID VITREOUS P2O5; NEUTRON-DIFFRACTION; RAMAN-SPECTROSCOPY; AB-INITIO; TRANSITION; SPECTRA; SILICA; BEHAVIOR; ALKALI AB A new forcefield model was developed for the computer simulation of phosphate materials. The model provides a fundamental basis for the evaluation of phosphate glass structure and thermodynamics, and was used to perform molecular dynamics (MD) simulations of a series of lithium phosphate glass compositions (xLi(2)O . (1 - x)P2O5, 0 less than or equal to x less than or equal to 0.5). Microstructural features and thermodynamic properties, as well as their correlations with chemical compositions, were analyzed. An important structural feature observed for the phosphate glasses was the occurrence of ring structures that were related to the chemical composition. Relative stability of the ring structures with respect to the number of phosphate tetrahedra within the ring was investigated using molecular orbital calculations on various phosphate conformations of clusters. An increase in stability was observed as the ring size increases from two- to four-membered rings. A larger abundance of the smallest ring size, the 3-membered rings (P3O3), corresponds to the minimum of the glass transition temperature (T-g) in the lithium phosphate glass series (corresponding to the composition 0.2Li(2)O . 0.8P(2)PO(5)). The impact of these strained 3-membered rings, along with the changes in the Li-coordination environment, on determining the spectroscopic and thermodynamic properties of the phosphate glasses is discussed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Dept Geochem, Albuquerque, NM 87185 USA. Bulk Mat Sandia Natl Labs, Dept Aging & Reliabil, Albuquerque, NM 87185 USA. RP Jiang, JJ (reprint author), Sandia Natl Labs, Dept Geochem, POB 5800, Albuquerque, NM 87185 USA. NR 38 TC 0 Z9 0 U1 1 U2 7 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 MAR PY 2000 VL 263 IS 1-4 BP 167 EP 179 PG 13 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 290AQ UT WOS:000085654500017 ER PT J AU Suratwala, TI Steele, RA Wilke, GD Campbell, JH Takeuchi, K AF Suratwala, TI Steele, RA Wilke, GD Campbell, JH Takeuchi, K TI Effects of OH content, water vapor pressure, and temperature on sub-critical crack growth in phosphate glass SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 15th University Conference on Glass Science CY JUN 20-23, 1999 CL UNIV MISSOURI ROLLA, ROLLA, MISSOURI SP Univ Missouri Rolla HO UNIV MISSOURI ROLLA ID MOLECULAR-WEIGHT; STRESS-CORROSION; SILICA GLASS; PROPAGATION; FATIGUE; PERFORMANCE; FRACTURE; LASER; MODEL AB The effects of temperature and water vapor pressure on the rate of sub-critical crack growth in meta-phosphate laser glasses containing different OH concentrations (128 and 773 ppmw) are reported. The crack velocity was measured using the double-cleavage-drilled-compression method. When plotted as a function of stress intensity, the samples have the classic region I, II and III crack growth properties similar to that reported for silicate glasses. The glass containing the larger OH content has a 10-fold greater crack velocity in region I; crack velocities is region II are the nearly the same for both glasses. The crack velocities are analyzed using a chemical kinetic and mass-transport limited reaction rate model. At temperatures >150 degrees C and water vapor pressures >10 mmHg, crack tip blunting is observed and the glass containing the larger OH content is more prone to blunting. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Hoya Corp USA, Fremont, CA 94538 USA. RP Suratwala, TI (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. RI Suratwala, Tayyab/A-9952-2013 OI Suratwala, Tayyab/0000-0001-9086-1039 NR 42 TC 63 Z9 67 U1 1 U2 14 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 MAR PY 2000 VL 263 IS 1-4 BP 213 EP 227 DI 10.1016/S0022-3093(99)00680-8 PG 15 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 290AQ UT WOS:000085654500023 ER PT J AU Hayden, JS Marker, AJ Suratwala, TI Campbell, JH AF Hayden, JS Marker, AJ Suratwala, TI Campbell, JH TI Surface tensile layer generation during thermal annealing of phosphate glass SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 15th University Conference on Glass Science CY JUN 20-23, 1999 CL UNIV MISSOURI ROLLA, ROLLA, MISSOURI SP Univ Missouri Rolla HO UNIV MISSOURI ROLLA AB Surface tensile layers (up to 20 MPa) are generated during thermal annealing of metaphosphate glass in ambient air. The surface tensile stress is caused by changes in properties of the phosphate glass, particularly the glass transition temperature and the coefficient of thermal expansion. due to the glass reaction with water vapor and diffusion of OH groups into the region just below the surface (<2 mm). Pin increase in the OH content of the glass from about 80 to 5000 ppmw causes a decrease in the glass transition temperature from 468 to 405 degrees C and an increase in the linear thermal expansion coefficient from 12.9 to 14.2 x 10(-6) K-1. A mechanism for the generation of the tensile surface layer is proposed and simulated experimentally by fusion-bonding at 500 degrees C two samples of the same composition but with OH contents that differ by up to 50x, The stresses in the annealed fusion-bonded samples are determined from measured stress birefringence, Peak tensile stresses calculated by finite element analysis agree with measured values to within 30%. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Schott Glass Technol Inc, Duryea, PA 18642 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Hayden, JS (reprint author), Schott Glass Technol Inc, 400 York Ave, Duryea, PA 18642 USA. RI Suratwala, Tayyab/A-9952-2013 OI Suratwala, Tayyab/0000-0001-9086-1039 NR 24 TC 19 Z9 20 U1 0 U2 1 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 MAR PY 2000 VL 263 IS 1-4 BP 228 EP 239 DI 10.1016/S0022-3093(99)00672-9 PG 12 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 290AQ UT WOS:000085654500024 ER PT J AU Ehrmann, PR Campbell, JH Suratwala, TI Hayden, JS Krashkevich, D Takeuchi, K AF Ehrmann, PR Campbell, JH Suratwala, TI Hayden, JS Krashkevich, D Takeuchi, K TI Optical loss and Nd3+ non-radiative relaxation by Cu, Fe and several rare earth impurities in phosphate laser glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 15th University Conference on Glass Science CY JUN 20-23, 1999 CL UNIV MISSOURI ROLLA, ROLLA, MISSOURI SP Univ Missouri Rolla HO UNIV MISSOURI ROLLA ID POLYVALENT IONS; REDOX BEHAVIOR; PERFORMANCE; SYSTEM; RANGE; IRON AB Extinction coefficients (at 1053 nm) and Nd3+ fluorescence quenching rates are reported for Cu, Fe, Dy, Pr, Sm and Ce at doping concentrations up to 1000 ppmw in two meta-phosphate laser glasses melted under oxidizing conditions (1 atmosphere O-2). The extinction coefficient and quenching rate for Cu are 2.7(+/-0.1) x 10(-3) cm(-1)/ppmw and 10.4 +/- 0.2 Hz/ppmw, respectively. The extinction coefficient and quenching rate for Fe are concentration dependent below 300 ppmw due to an observed change in Fe2+/Fe3+ distribution; an empirically derived expression is used to describe this effect. The extinction coefficient and quenching rates for Dy, Pr and Sm, are nearly the same: 1.6, 1.2 and 1.3(+/-0.05) x 10(-5) cm(-1)/ppmw and 0.89, 0.72 and 0.63 +/- 0.04 Hz/ppmw, respectively, while those for Ce are less: 0.84(+/-0.03) x 10(-5) cm(-1)/ppmw and 0.061 +/- 0.03 Hz/ppmw. The quenching results are explained using the Forster-Dexter theory for dipolar energy transfer. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Schott Glass Technol Inc, Duryea, PA 18642 USA. Hoya Corp, Fremont, CA 94538 USA. RP Ehrmann, PR (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-500, Livermore, CA 94550 USA. RI Suratwala, Tayyab/A-9952-2013 OI Suratwala, Tayyab/0000-0001-9086-1039 NR 40 TC 23 Z9 25 U1 0 U2 11 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 MAR PY 2000 VL 263 IS 1-4 BP 251 EP 262 DI 10.1016/S0022-3093(99)00682-1 PG 12 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 290AQ UT WOS:000085654500026 ER PT J AU Campbell, JH Suratwala, TI AF Campbell, JH Suratwala, TI TI Nd-doped phosphate glasses for high-energy/high-peak-power lasers SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 15th University Conference on Glass Science CY JUN 20-23, 1999 CL UNIV MISSOURI ROLLA, ROLLA, MO SP Univ Missouri Rolla HO UNIV MISSOURI ROLLA ID RARE-EARTH IONS; RADIATIVE TRANSITION-PROBABILITIES; SODIUM ULTRAPHOSPHATE GLASSES; INERTIAL CONFINEMENT FUSION; JUDD-OFELT PARAMETERS; SPECTROSCOPIC PROPERTIES; ALUMINOPHOSPHATE GLASS; METAPHOSPHATE GLASSES; SPECTRAL PROPERTIES; FLUORIDE PHOSPHATE AB The composition and properties of neodymium-doped (Nd-duped) phosphate glasses used for simultaneous high-energy (10(3)-10(6) J) and high-peak-power (10(12)-10(15) W) laser applications such as fusion energy research, are reviewed. The most common base glasses are meta-phosphates (O/P similar to 3) with the approximate composition: 60P(2)O(5)-10Al(2)O(3)-30M(2)O/MO; K/Ba or K/Mg are typical modifiers. The spectroscopy of Nd3+ in these glasses is well understood and laser properties can be accurately determined from measured spectroscopic properties. The major mechanisms for Nd3+ non-radiative relaxation are reviewed and empirical expressions are presented that predict these effects in phosphate glasses. Optical and thermal-mechanical properties have been measured on a number of laser glasses and can be correlated with composition. Sub-critical crack growth rates in stress regions I, II and III have been reported for the first time in phosphate laser grasses. The mechanism for Pt inclusion formation and dissolution has been studied leading to damage resistant (Pt-inclusion-free) laser glasses, (C) 2000 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. EM campbell12@llnl.gov RI Suratwala, Tayyab/A-9952-2013 OI Suratwala, Tayyab/0000-0001-9086-1039 NR 141 TC 309 Z9 323 U1 7 U2 58 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 EI 1873-4812 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAR PY 2000 VL 263 IS 1-4 BP 318 EP 341 DI 10.1016/S0022-3093(99)00645-6 PG 24 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 290AQ UT WOS:000085654500035 ER PT J AU Campbell, JH Suratwala, TI Thorsness, CB Hayden, JS Thorne, AJ Cimino, JM Marker, AJ Takeuchi, K Smolley, M Ficini-Dorn, GF AF Campbell, JH Suratwala, TI Thorsness, CB Hayden, JS Thorne, AJ Cimino, JM Marker, AJ Takeuchi, K Smolley, M Ficini-Dorn, GF TI Continuous melting of phosphate laser glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 15th University Conference on Glass Science CY JUN 20-23, 1999 CL UNIV MISSOURI ROLLA, ROLLA, MISSOURI SP Univ Missouri Rolla HO UNIV MISSOURI ROLLA ID PERFORMANCE; SYSTEM AB Continuous melting of phosphate laser glass is being used for the first time to prepare meter-scale amplifier optics for megajoule lasers, a description of the melting process is given. Two key factors in the successful melting of laser glasses are the elimination of damage-causing Pt-inclusions and dehydroxylation of the glass to concentrations less than similar to 100 ppmw OH. Oxidizing conditions using 100% O-2 or O-2 + Cl-2 mixtures (at one atmosphere) can be used to dissolve Pt inclusions and the effects of different gases on the dissolution of Pt-inclusions show the trend O-2 + Cl-2 > O-2 much greater than N-2. The removal of hydroxyl groups is achieved by reactive (O-2 + Cl-2) or non-reactive (O-2) gas bubbling; model calculations are used to simulate this process. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Schott Glass Technol, Duryea, PA 18642 USA. Hoya Corp USA, Fremont, CA 94538 USA. ECO, Ctr Etud Limeil Valenton, EME, F-94795 Villeneuve St Georges, France. RP Campbell, JH (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. RI Suratwala, Tayyab/A-9952-2013 OI Suratwala, Tayyab/0000-0001-9086-1039 NR 57 TC 65 Z9 74 U1 1 U2 14 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 MAR PY 2000 VL 263 IS 1-4 BP 342 EP 357 DI 10.1016/S0022-3093(99)00675-4 PG 16 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 290AQ UT WOS:000085654500036 ER PT J AU Raman, SV AF Raman, SV TI Properties of metal phosphates and phosphides in glass-ceramic waste forms SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 15th University Conference on Glass Science CY JUN 20-23, 1999 CL UNIV MISSOURI ROLLA, ROLLA, MISSOURI SP Univ Missouri Rolla HO UNIV MISSOURI ROLLA ID APATITES; ORDER AB Condensed glass-ceramic waste forms were developed by partial vitrification in a hot isostatic press. The calcined nuclear waste simulants, inclusive of volatiles, are partitioned among a variety of crystalline phases and glass. Phosphorus occurs largely in orthophosphate and phosphide crystals. X-ray powder diffraction analysis reveals changes in the 'c/a' lattice parameters coincident with cadmium and cerium substitutions for calcium in fluor-apatite. The chemical durability of fluor-apatite is not affected by the changes in the cia ratio. The limited solubility of Ce and Cd in calcium fluor-apatite is attributed to differences in Cd-O and Ce-O hybrid bonding orbitals. Similarly, the covalent linkage between phosphorus and oxygen in the PO43- tetrahedra is conceptualized in terms of hybrid bonding. In addition to phosphates, metal phosphides occur dispersed in the glass matrix and their compositions Vary with changes in partial pressure of oxygen. Hybrid electron orbitals are proposed for the coordinating linkage between metals (M) and phosphorus (P). In (Fe, Cr)P-4, (Cd, Zr)P-4 and Zr3P4 phases, the M and P hybrid orbitals overlap more than in the phase (B, Ca, Sr, Cs, K, Na)(4)P and contribute to a greater durability for the former phases. In both phosphates and phosphides, the hybrid bonding concept leads to the speculation that non-bonding itinerant electrons originate from phosphorus and are expectably localized by the negatively charged oxygen barriers in the phosphate. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Dept Nucl Engn, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83402 USA. RP Raman, SV (reprint author), Dept Nucl Engn, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83402 USA. NR 34 TC 4 Z9 5 U1 2 U2 7 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 MAR PY 2000 VL 263 IS 1-4 BP 395 EP 408 DI 10.1016/S0022-3093(99)00648-1 PG 14 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 290AQ UT WOS:000085654500042 ER PT J AU Yi, JJL Yu, KM AF Yi, JJL Yu, KM TI Surface studies of semiconducting glass using ion beam methods SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 15th University Conference on Glass Science CY JUN 20-23, 1999 CL UNIV MISSOURI ROLLA, ROLLA, MISSOURI SP Univ Missouri Rolla HO UNIV MISSOURI ROLLA AB We have studied the near surface stoichiometry of a semiconducting vanadium phosphate glass for microchannel plate application using MeV ion beam techniques including Rutherford backscattering spectrometry (RBS), particle induced X-ray emission (PIXE) and elastic recoil detection (ERD) analysis. A conventional microchannel plate made of dielectric lead silicate glass with a surface conducting layer was also measured for comparison, The elemental profiles of the two samples showed that the semiconducting glass have a more uniform surface structure as compared to conventional microchannel prate glasses suggesting that the former is more stable. We suggest that our results indicate microchannel plates (MCPs) made of semiconducting glass should have long-term stability and therefore should have longer service life. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Circon ACMI, Stamford, CT 06904 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Yi, JJL (reprint author), Circon ACMI, 300 Stillwater Ave, Stamford, CT 06904 USA. RI Yu, Kin Man/J-1399-2012 OI Yu, Kin Man/0000-0003-1350-9642 NR 19 TC 0 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAR PY 2000 VL 263 IS 1-4 BP 416 EP 421 DI 10.1016/S0022-3093(99)00679-1 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 290AQ UT WOS:000085654500044 ER PT J AU Lee, EH Mansur, LK AF Lee, EH Mansur, LK TI Fe-15Ni-13Cr austenitic stainless steels for fission and fusion reactor applications. I. Effects of minor alloying elements on precipitate phases in melt products and implication in alloy fabrication SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID NI-CR ALLOYS; OXYGEN AB In an effort to develop alloys for fission and fusion reactor applications, 28Fe-15Ni-13Cr base alloys were fabricated by adding various combinations of the minor alloying elements, Mo, Ti, C, Si, P, Nb, and B. The results showed that a significant fraction of undesirable residual oxygen was removed as oxides when Ti, C, and Si were added. Accordingly, the concentrations of the latter three essential alloying elements were reduced also. Among these elements, Ti was the strongest oxide former, but the largest oxygen removal lover 80%) was observed when carbon was added alone without Ti, since gaseous CO boiled off during melting. This paper recommends an alloy melting procedure to mitigate solute losses while reducing the undesirable residual oxygen. In this work, 14 different types of precipitate phases were identified. Compositions of precipitate phases and their crystallographic data are documented. Finally, stability of precipitate phases was examined in view of Gibbs free energy of formation. (C) 2000 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 18 TC 9 Z9 9 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2000 VL 278 IS 1 BP 1 EP 10 DI 10.1016/S0022-3115(99)00234-2 PG 10 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 279XF UT WOS:000085069800001 ER PT J AU Lee, EH Mansur, LK AF Lee, EH Mansur, LK TI Fe-15Ni-13Cr austenitic stainless steels for fission and fusion reactor applications. II. Effects of minor elements on precipitate phase stability during thermal aging SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID IRRADIATION; ALLOYS AB The precipitate phase stability in Fe-15Ni-13Cr base austenitic alloys was investigated as a function of minor alloying additions after thermally aging at 600 degrees C and 675 degrees C for times ranging from 24 h to one year. Seven major precipitate phases were found in aged specimens, including M23C6, Laves, Era (eta), TiO, NbC, MC, and M2P. The types and amounts of precipitate phases varied with alloying element additions, aging temperature, and aging time. By analyzing the composition of each individual particle, it was possible to determine the essential constituent elements for each phase. From this information, a strategy to promote or suppress certain precipitate phases was developed. Among the seven phases, the most desirable precipitate phases were considered to be MC and M2P, because these particles form on a fine scale with a high number density and, therefore, can serve as effective gas atom trap sites under irradiation. (C) 2000 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 28 TC 14 Z9 16 U1 1 U2 7 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 MAR PY 2000 VL 278 IS 1 BP 11 EP 19 DI 10.1016/S0022-3115(99)00235-4 PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 279XF UT WOS:000085069800002 ER PT J AU Lee, EH Mansur, LK AF Lee, EH Mansur, LK TI Fe-15Ni-13Cr austenitic stainless steels for fission and fusion reactor applications. III. Phase stability during heavy ion irradiation SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID CR-NI ALLOYS; MICROSTRUCTURAL EVOLUTION; PRECIPITATION AB The phase stability in Fe-15Ni-13Cr alloys was investigated as a function of minor alloying additions after 4 MeV Ni ion irradiation at 948 K. The results showed that the stability of precipitate phases was dictated mainly by the defects produced by radiation damage and preferential segregation of Si and Ni at defects. In addition, radiation enhanced diffusion and cascade induced dissolution and mixing allowed kinetically sluggish phases to form rapidly under irradiation. These radiation effects caused an enhancement, retardation, or modification of thermal phases, and formation of new phases. The relative stability of precipitate phases varied sensitively with alloy composition. The roles of each alloying element on phase stability and the impact of radiation on the mechanisms of phase evolution were systematically studied and documented. The knowledge obtained from this work provides guidelines for designing alloys that lead to develop desired precipitate microstructures under irradiation. (C) 2000 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 35 TC 12 Z9 12 U1 1 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAR PY 2000 VL 278 IS 1 BP 20 EP 29 DI 10.1016/S0022-3115(99)00236-6 PG 10 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 279XF UT WOS:000085069800003 ER PT J AU Hooper, EB Cohen, RH Ryutov, DD AF Hooper, EB Cohen, RH Ryutov, DD TI Theory of edge plasma in a spheromak SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 13th International Conference on Plasma-Surface Interactions in Controlled Fusion Devices CY MAY 18-22, 1998 CL SAN DIEGO, CALIFORNIA SP Gen Atomics Co, US DOE AB Properties of the edge plasma in the SSPX spheromak during the plasma formation and sustainment phases are discussed. For the breakdown and formation phase, the main emphasis is on the analysis of possible plasma contamination by impurities from the electrodes of the plasma gun (helicity injector). The issue of an azimuthally uniform breakdown initiation is also discussed. After the plasma settles down in the main vacuum chamber, one has to sustain the current between the electrodes, in order to continuously inject helicity. We discuss properties of the plasma on the field lines intersecting the electrodes. We conclude that the thermal balance of this plasma is maintained by Joule heating competing with parallel heat losses to the electrodes. The resulting plasma temperature is in the range 15-30 eV. Under the expected operational conditions, the 'current' velocity of the: electrons is only slightly below their thermal velocity. Implications of this observation are briefly discussed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Hooper, EB (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-637, Livermore, CA 94550 USA. NR 7 TC 9 Z9 9 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 MAR PY 2000 VL 278 IS 1 BP 104 EP 110 DI 10.1016/S0022-3115(99)00217-2 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 279XF UT WOS:000085069800012 ER PT J AU Lotz, JC Kroeber, MW Heilmann, M Pericherla, K Kimmel, D Kinney, JH Lane, NE AF Lotz, JC Kroeber, MW Heilmann, M Pericherla, K Kimmel, D Kinney, JH Lane, NE TI Tibial plateau fracture as a measure of early estrogen-dependent bone fragility in rats SO JOURNAL OF ORTHOPAEDIC RESEARCH LA English DT Article ID OVARIECTOMIZED RATS; PARATHYROID-HORMONE; TRABECULAR BONE; BIOMECHANICAL PROPERTIES; MECHANICAL-PROPERTIES; IN-VIVO; MASS; STRENGTH; PROSTAGLANDIN; CONNECTIVITY AB The goals of this study were to develop a protocol to induce a compressive fracture at the tibial plateau of the rat knee in vitro and to determine if the biomechanical parameters provided a sensitive assessment of the early skeletal changes induced by estrogen deficiency. Sixty-one rats underwent an ovariectomy (n = 36) or sham operation (n = 25) and were maintained for 50 days after the procedure. Just before death, the proximal tibia of each animal was scanned with high-resolution x-ray tomography. From the three-dimensional images, the mean trabecular bone volume, thickness, and separation and the number of trabeculae were calculated. The knees were then harvested and mounted into a servohydraulic materials testing system so that the distal femoral condyle could be forced into the proximal tibial plateau until fracture. The fracture load of the ovariectomized rats was 24% less than that of the rats that had the sham operation. Similarly, the structural stiffness of the ovariectomized knees was decreased by 22%. Both of these differences were statistically significant (p < 0.01) and were explained by differences in trabecular bone volume (r = 0.56, p < 0.0001 and r = 0.42, p < 0.005, respectively). The other measures of trabecular bone structure were correlated with the volume and did not improve the prediction by the biomechanical parameters. These data demonstrate that biomechanical testing of the tibial plateau in rats can quantify the structural consequences of estrogen deficiency at an early time point before they become apparent at other bone sites, such as the lumbar spine. C1 Univ Calif San Francisco, Orthopaed Bioengn Lab, San Francisco, CA 94143 USA. Univ Calif San Francisco, Sch Med, San Francisco, CA 94143 USA. Creighton Univ, Sch Med, Osteoporosis Res Ctr, Omaha, NE USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Lotz, JC (reprint author), Univ Calif San Francisco, Orthopaed Bioengn Lab, 533 Parnassus Ave, San Francisco, CA 94143 USA. NR 26 TC 3 Z9 3 U1 0 U2 1 PU JOURNAL BONE JOINT SURGERY INC PI NEEDHAM PA 20 PICKERING ST, NEEDHAM, MA 02192 USA SN 0736-0266 J9 J ORTHOPAED RES JI J. Orthop. Res. PD MAR PY 2000 VL 18 IS 2 BP 326 EP 332 DI 10.1002/jor.1100180223 PG 7 WC Orthopedics SC Orthopedics GA 312NK UT WOS:000086949200022 PM 10815836 ER PT J AU Kaszuba, JP Wendlandt, RF AF Kaszuba, JP Wendlandt, RF TI Effect of carbon dioxide on dehydration melting reactions and melt compositions in the lower crust and the origin of alkaline rocks SO JOURNAL OF PETROLOGY LA English DT Article DE alkali basalt; alkaline rocks; carbon dioxide; dehydration melting; phonolite ID FLOOD PHONOLITES; PHASE-RELATIONS; KENYA RIFT; 10 KBAR; ARCHEAN TRONDHJEMITES; CONTINENTAL-CRUST; TONALITIC GNEISS; SILICATE MELTS; HIGH-PRESSURE; WEST-GERMANY AB Dehydration melting experiments of alkali basalt associated with the Kenya Rift were performed at 0.7 and 1.0 GPa, 850-1100 degrees C, 3-5 wt % H2O, and f(O2) near nickel-nickel oxide. Carbon dioxide [X-CO2 = molar CO2/(H2O + CO2) = 0.2-0.9] was added to experiments at 1025 and 1050 degrees C. Dehydration melting in the system alkali basalt-H2O produces quartz- and corundum-normative tracyandesite (6-7.5 wt % total alkalis) at 1000 and 1025 degrees C by the incongruent melting of amphibole (paragasite-magnesiohastingsite). Dehydration melting in the system alkali basalt-H2O-CO2 produces nepheline-normative tephriphonolite, trachyandesite, and trachyte (10.5-12 wt % total alkalis). In the latter case, the solidus is raised relative to the hydrous system, less melt is produced and the incongruent melting reaction involves kaersutite. The role of carbon dioxide in alkaline magma genesis is well documented for mantle systems. This study shows that carbon dioxide is also important to the petrogenesis of alkaline magmas at the lower pressures of crustal systems. Select suites of continental alkaline rocks, including those containing phonolite, may be derived by low-pressure dehydration melting of an alkali basalt-carbon dioxide crustal system. C1 Colorado Sch Mines, Dept Geol & Geol Sci, Golden, CO 80401 USA. RP Kaszuba, JP (reprint author), Univ Calif Los Alamos Natl Lab, Div Environm Sci & Technol, E-ET,Mail Stop J514, Los Alamos, NM 87545 USA. NR 70 TC 30 Z9 31 U1 0 U2 5 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-3530 J9 J PETROL JI J. Petrol. PD MAR PY 2000 VL 41 IS 3 BP 363 EP 386 DI 10.1093/petrology/41.3.363 PG 24 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 286WC UT WOS:000085471000004 ER PT J AU Cullander, C Jeske, S Imbert, D Grant, PG Bench, G AF Cullander, C Jeske, S Imbert, D Grant, PG Bench, G TI A quantitative minimally invasive assay for the detection of metals in the stratum corneum SO JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS LA English DT Article DE tape-stripping; skin; particle induced X-ray emission; stratum corneum ID PERCUTANEOUS-ABSORPTION; NUCLEAR MICROPROBE; SKIN; MICROANALYSIS; LIVERMORE; PACKAGE AB A quantitative, minimally invasive tape-stripping assay for the detection of metals on and in skin that also has application to the detection of metallic elements on dry surfaces (where human contact could occur) has been developed. This development included construction, using commercial products, of an approximately 25 mu m thick, low-metal content tape suitable both for tape-stripping and elemental analysis. Individual tapes were sequentially applied to the skin surface and then removed, taking with them a sample of the dead outer layer of the skin (stratum corneum). Analysis of such tape strip samples by particle induced X-ray emission (PIXE) - a well-characterized, sensitive, analytical technique based on X-ray spectrometry - identified and accurately quantified the metals in the sample. The assay had elemental sensitivities of approximately 1 ng/cm(2) for many metals and analysis of elemental contents could be performed in as little as 5 min. The feasibility of the assay for measuring metals in the stratum corneum was demonstrated on the forearms of healthy human volunteers. Samples from approximately half the subjects were found to contain zirconium, possibly arising from the use of roll-on antiperspirants. The assay has potential as a tool: (1) for risk assessment, (2) to identify exposure levels following possible contact with a hazardous metal, and (3) to determine the effectiveness of cleanup or removal measures. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif San Francisco, Sch Pharm, Dept Biopharmaceut Sci, San Francisco, CA 94143 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. RP Cullander, C (reprint author), Univ Calif San Francisco, Sch Pharm, Dept Biopharmaceut Sci, 513 Parnassus Ave, San Francisco, CA 94143 USA. RI imbert, daniel/H-7850-2014 NR 17 TC 16 Z9 16 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0731-7085 J9 J PHARMACEUT BIOMED JI J. Pharm. Biomed. Anal. PD MAR PY 2000 VL 22 IS 2 BP 265 EP 279 DI 10.1016/S0731-7085(99)00248-4 PG 15 WC Chemistry, Analytical; Pharmacology & Pharmacy SC Chemistry; Pharmacology & Pharmacy GA 290BL UT WOS:000085656400007 PM 10719909 ER PT J AU Montano, PA Ruett, U Beno, MA Jennings, G Kimball, CW AF Montano, PA Ruett, U Beno, MA Jennings, G Kimball, CW TI Magnetic compton scattering using the elliptical multipole wiggler at sector 11-ID-B SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Workshop on Inelastic X-ray Scattering CY OCT 18-21, 1998 CL LONG ISL CITY, NEW YORK SP US DOE, Div Mat Sci, Argonne Natl Lab, Blake Ind, Brookhaven Natl Lab, Brookhaven Sci Assoc, Oak Ridge Natl Lab, Synchrotron Radiat Res Ctr DE magnet polarity ID IRON AB Magnetic Compton scattering has been used to measure the momentum distribution of magnetic electrons in several materials. The polarization and frequency tunability of the elliptical multipole wiggler (EMW) makes it an ideal source for magnetic Compton scattering experiments. We performed the measurements using 50, 100 and 150 keV photons simultaneously. The EMW was operated at K-y = 14 (E-c = 32 keV) and K-x between 0.6 and 1.03. The degree of circular polarization was about 80% or higher. The sample was mounted between the poles of an electromagnet in a field of 0.8 T. The majority of Compton scattering measurements were performed by switching the magnet polarity. Tests using an iron foil target gave a similar magnetic Compton profile by either switching the magnetic field or the photon helicity. A 9-element Ge solid state detector array was used for detection. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Illinois, Dept Phys, Chicago, IL 60680 USA. No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. RP Montano, PA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 1 Z9 1 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAR PY 2000 VL 61 IS 3 BP 353 EP 356 DI 10.1016/S0022-3697(99)00315-7 PG 4 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 286XL UT WOS:000085474100005 ER PT J AU Eguiluz, AG Ku, W Sullivan, JM AF Eguiluz, AG Ku, W Sullivan, JM TI Dynamical response of correlated electrons in solids probed by inelastic scattering experiments: an ab initio theoretical perspective SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Workshop on Inelastic X-ray Scattering CY OCT 18-21, 1998 CL LONG ISL CITY, NY SP US DOE, Div Mat Sci, Argonne Natl Lab, Blake Ind, Brookhaven Natl Lab, Brookhaven Sci Assoc, Oak Ridge Natl Lab, Synchrotron Radiat Res Ctr DE X-ray scattering spectroscopy ID X-RAY-SCATTERING; DENSITY-FUNCTIONAL THEORY; LI METAL; COMPTON PROFILES; GW APPROXIMATION; BAND-STRUCTURE; ALKALI-METALS; SELF-ENERGY; AL METAL; GAS AB We present results of ab initio theoretical investigations of the excitation spectra of correlated electrons in metals (Al, K, and Li) and their interplay with inelastic scattering experiments. We resolve various anomalies contained in the data, which were originally viewed as signatures of strong dynamical electronic correlations; we show that, instead, the anomalies are due to band-structure effects. The underlying theoretical framework in our density-response calculations is time-dependent density-functional theory; with this scheme we discuss the lifetime of the K plasmon, and the dynamical structure factor of Al. From a self-consistent solution of the Dyson equation in the GW approximation for the electron self-energy, we discuss the electron momentum density in Li. Our results and methods point to a new way of thinking about electronic excitations in real materials. The main challenge ahead is the proper treatment of dynamical correlations for realistic representations of the band structure. (C) 2000 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Eguiluz, AG (reprint author), Univ Tennessee, Dept Phys & Astron, 1401 Circle Dr, Knoxville, TN 37996 USA. EM eguiluz@utk.edu NR 47 TC 18 Z9 18 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAR PY 2000 VL 61 IS 3 BP 383 EP 390 DI 10.1016/S0022-3697(99)00322-4 PG 8 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 286XL UT WOS:000085474100012 ER PT J AU Larson, BC Tischler, JZ Fleszar, A Eguiluz, AG AF Larson, BC Tischler, JZ Fleszar, A Eguiluz, AG TI Correlation and band structure effects in the electronic energy loss spectra of Al: an experimental perspective SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Workshop on Inelastic X-ray Scattering CY OCT 18-21, 1998 CL LONG ISL CITY, NEW YORK SP US DOE, Div Mat Sci, Argonne Natl Lab, Blake Ind, Brookhaven Natl Lab, Brookhaven Sci Assoc, Oak Ridge Natl Lab, Synchrotron Radiat Res Ctr DE band structure ID X-RAY-SCATTERING; DYNAMIC STRUCTURE FACTOR; METAL; LIQUID; ALUMINUM; STATE; GASES; LI AB Inelastic X-ray scattering measurements in aluminum are analyzed using first principles dynamical density response calculations including band structure, Band structure effects are shown to be important; significant effects include shifts of spectral features to lower energies and the presence of high-energy tails, in addition to the much discussed energy gaps and zone-boundary collective states. These non-jellium characteristics must be considered in investigating exchange and correlation effects in simple metals. Published by Elsevier Science Ltd. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Wurzburg, Inst Phys, D-97074 Wurzburg, Germany. Univ Tennessee, Dept Phys & Astronomy, Knoxville, TN 37996 USA. RP Larson, BC (reprint author), Oak Ridge Natl Lab, Div Solid State, Bldg 3025,POB 2008, Oak Ridge, TN 37831 USA. NR 29 TC 4 Z9 4 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAR PY 2000 VL 61 IS 3 BP 391 EP 396 DI 10.1016/S0022-3697(99)00323-6 PG 6 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 286XL UT WOS:000085474100013 ER PT J AU Montano, PA Macrander, AT AF Montano, PA Macrander, AT TI Inelastic X-ray scattering study of Cr(110): from low momentum transfer to the Compton scattering limit SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Workshop on Inelastic X-ray Scattering CY OCT 18-21, 1998 CL LONG ISL CITY, NEW YORK SP US DOE, Div Mat Sci, Argonne Natl Lab, Blake Ind, Brookhaven Natl Lab, Brookhaven Sci Assoc, Oak Ridge Natl Lab, Synchrotron Radiat Res Ctr DE inelastic X-ray scattering ID CR; AUTOIONIZATION; METAL; TI; LI AB Inelastic X-ray scattering (IXS) is an important tool to study a large number of physical properties in condensed matter systems. We use this technique to study electronic excitations in Cr(110). The IXS spectra were measured at sector 12-ID-B (BESSRC) at the APS. We used a backscattering geometry for the analyzer crystal, Ge (444) at 7.6 keV and Ge (555) at 9.5 keV. We used the BESSRC cryogenically cooled monochromator to select the desired energy, 180 meV resolution was obtained when using the Si (333) reflection. The spectra were obtained by scanning the incident energy with a fixed analyzer setting, inelastic X-ray scattering spectra were measured for a range of momentum transfers extending from 0.80 to 5.0 Angstrom(-1). We find spectral features corresponding to plasmons excitations, as well as a second peak corresponding to excitation from the 3p core states to the 3d valence states of Cr. This peak shows strong momentum dependence with no detectable intensity at low momentum transfer. We observed at high momentum transfer the appearance of a Compton scattering peak. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Illinois, Dept Phys, Chicago, IL 60680 USA. Argonne Natl Lab, Adv Photon Source, Expt Facil Div, Argonne, IL 60439 USA. RP Montano, PA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 2 Z9 2 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAR PY 2000 VL 61 IS 3 BP 415 EP 418 DI 10.1016/S0022-3697(99)00328-5 PG 4 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 286XL UT WOS:000085474100018 ER PT J AU Hill, JP Kao, CC Hamalainen, K Huotari, S Berman, LE Caliebe, WAL Matsubara, M Kotani, A Peng, JL Greene, RL AF Hill, JP Kao, CC Hamalainen, K Huotari, S Berman, LE Caliebe, WAL Matsubara, M Kotani, A Peng, JL Greene, RL TI Energy and polarization dependence of resonant inelastic X-ray scattering in Nd2CuO4 SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Workshop on Inelastic X-ray Scattering CY OCT 18-21, 1998 CL LONG ISL CITY, NEW YORK SP US DOE, Div Mat Sci, Argonne Natl Lab, Blake Ind, Brookhaven Natl Lab, Brookhaven Sci Assoc, Oak Ridge Natl Lab, Synchrotron Radiat Res Ctr DE X-ray ID EMISSION SPECTROSCOPY; K-EDGE; SPECTRA; LA2CUO4; EXCITATIONS; ABSORPTION; CUO AB We report the energy and polarization dependence of resonant inelastic X-ray scattering from Nd2CuO4. An energy loss feature at similar to 6 eV is observed in the vicinity of the Cu K-edge. Numerical calculations based on the Anderson impurity model identify this as a charge transfer excitation to the anti-bonding state. The incident polarization is shown to select the intermediate states participating in the resonance process. Resonances are observed at 8990 and 9000 eV with the incident polarization perpendicular and parallel to the CuO planes, respectively. In contrast to our single-site model calculations, no resonances are observed associated with the 1s3d(10)L intermediate states, suggesting that non-local effects play a role. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. Univ Tokyo, Inst Solid State Phys, Minato Ku, Tokyo 106, Japan. Univ Maryland, Dept Phys & Astron, Ctr Superconduct Res, College Pk, MD 20742 USA. RP Hill, JP (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Hamalainen, Keijo/A-3986-2010; Hill, John/F-6549-2011 OI Hamalainen, Keijo/0000-0002-9234-9810; NR 15 TC 4 Z9 4 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAR PY 2000 VL 61 IS 3 BP 425 EP 429 DI 10.1016/S0022-3697(99)00330-3 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 286XL UT WOS:000085474100020 ER PT J AU Mamontov, E Dmowski, W Egami, T Kao, CC AF Mamontov, E Dmowski, W Egami, T Kao, CC TI Electronic excitation in a catalytic support oxide, CeO2 SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Workshop on Inelastic X-ray Scattering CY OCT 18-21, 1998 CL LONG ISL CITY, NEW YORK SP US DOE, Div Mat Sci, Argonne Natl Lab, Blake Ind, Brookhaven Natl Lab, Brookhaven Sci Assoc, Oak Ridge Natl Lab, Synchrotron Radiat Res Ctr DE X-ray resonant Raman scattering ID SCATTERING AB X-ray resonant Raman scattering (XRRS) measurements were performed on a single crystal of ceria, CeO2, near the Ce Lm edge. Ceria is an important component of automotive catalytic converters, and helps to maintain the oxygen pressure in the vicinity of metal catalysts through the valence change Ce4+ <----> Ce3+. The XRRS spectra show rich features of electronic excitations in ceria involving various f state occupations of cerium that change with temperature and/or surface composition. Determining the electronic process that leads to valence change would facilitate the understanding of the buffering function of ceria. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Univ Penn, Res Struct Matter Lab, Philadelphia, PA 19104 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Egami, T (reprint author), Univ Penn, Dept Mat Sci & Engn, 3231 Walnut St, Philadelphia, PA 19104 USA. RI Mamontov, Eugene/Q-1003-2015 OI Mamontov, Eugene/0000-0002-5684-2675 NR 8 TC 7 Z9 7 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAR PY 2000 VL 61 IS 3 BP 431 EP 433 DI 10.1016/S0022-3697(99)00331-5 PG 3 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 286XL UT WOS:000085474100021 ER PT J AU Ederer, DL Moewes, A Kurmaev, EZ Callcott, TA Grush, MM Stadler, S Winarski, R Perera, RCC Terminello, LJ AF Ederer, DL Moewes, A Kurmaev, EZ Callcott, TA Grush, MM Stadler, S Winarski, R Perera, RCC Terminello, LJ TI Resonant Raman scattering in Nd2O3 and the electronic structure of Sr2RuO4 Studied by synchrotron radiation excitation SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Workshop on Inelastic X-ray Scattering CY OCT 18-21, 1998 CL LONG ISL CITY, NEW YORK SP US DOE, Div Mat Sci, Argonne Natl Lab, Blake Ind, Brookhaven Natl Lab, Brookhaven Sci Assoc, Oak Ridge Natl Lab, Synchrotron Radiat Res Ctr DE soft X-ray spectroscopy ID X-RAY-FLUORESCENCE; NONCUPRATE SUPERCONDUCTOR SR2RUO4; EXTENDED VANHOVE SINGULARITY; INELASTIC-SCATTERING; EMISSION-SPECTROSCOPY; BAND-STRUCTURE; GRATING MONOCHROMATOR; UNDULATOR BEAMLINE; ENERGY DEPENDENCE; SI AB This paper is intended to illustrate two points. The first is the extensive growth of resonant Raman soft X-ray scattering due to the emergence of third-generation X-ray sources, With these sources, the ubiquitous presence of Raman scattering near the 3d and 4d ionization thresholds has been used to elucidate the excitation process in a number of rare earth and transition metal compounds. Such scattering can produce dramatic changes in the emission spectrum, as we show in our example of inelastic scattering at the 3d threshold of Nd2O3 Photon-in photon-out soft X-ray spectroscopy is adding a new dimension to soft X-ray spectroscopy by providing many opportunities for exciting research, especially at third-generation synchrotron light sources, Second, it is very effective to use theory and experiment to characterize the electronic properties of materials. In particular we confirmed in-plane oxygen-ruthenium bonding in Sr2RuO4, the first copperless perovskite superconductor, by analyses using calculations, soft X-ray emission spectroscopy (SXE) and photoelectron spectroscopy (PES). Measurements of this type illustrate the importance of combining SXE and PES measurements with theoretical calculations. (C) 2000 Published by Elsevier Science Ltd. All rights reserved. C1 Tulane Univ, New Orleans, LA 70118 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. USN, Res Lab, Washington, DC 20021 USA. Ctr Adv Microstruct & Devices, Baton Rouge, LA 70888 USA. Russian Acad Sci, Inst Phys Met, Ural Div, Yekaterinburg 620219, Russia. Univ Tennessee, Knoxville, TN 37996 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Ederer, DL (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RI Kurmaev, Ernst/J-4254-2013 OI Kurmaev, Ernst/0000-0003-4625-4930 NR 64 TC 1 Z9 1 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAR PY 2000 VL 61 IS 3 BP 435 EP 444 DI 10.1016/S0022-3697(99)00332-7 PG 10 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 286XL UT WOS:000085474100022 ER PT J AU Qian, Q Tyson, TA Kao, CC Rueff, JP deGroot, FMF Croft, M Cheong, SW Greenblatt, M Subramanian, MA AF Qian, Q Tyson, TA Kao, CC Rueff, JP deGroot, FMF Croft, M Cheong, SW Greenblatt, M Subramanian, MA TI Valence measurement of Mn oxides using Mn K-beta emission spectroscopy SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Workshop on Inelastic X-ray Scattering CY OCT 18-21, 1998 CL LONG ISL CITY, NEW YORK SP US DOE, Div Mat Sci, Argonne Natl Lab, Blake Ind, Brookhaven Natl Lab, Brookhaven Sci Assoc, Oak Ridge Natl Lab, Synchrotron Radiat Res Ctr DE valence measurement ID EDGE AB High resolution Mn K-beta emission spectra provide a direct method to probe the effective spin state and charge density on Mn sites. Direct comparison of MnF2 and MnO reveals significant changes due to the degree of covalency. The detailed shape and energy shift of thr spectra for the perovskite LaMnO3 and CaMnO3 compounds are found to be very similar to Mn2O3 and MnO2, respectively. Detailed Mn K-beta X-ray emission results on La1-xCaxMnO3 can be well fit by linear superpositions of the end member spectra. However, for x < 0.3, a retarded response is found. No evidence for Mn2+ is found. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. New Jersey Inst Technol, Dept Phys, Newark, NJ 07102 USA. Univ Nijmegen, NL-6526 ED Nijmegen, Netherlands. Rutgers State Univ, Dept Phys, Piscataway, NJ 08855 USA. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Rutgers State Univ, Dept Chem, Piscataway, NJ 08855 USA. Dupont Co, Cent Res & Dev, Wilmington, DE 19880 USA. RP Kao, CC (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI de Groot, Frank/A-1918-2009; Rueff, Jean-Pascal/D-8938-2016 OI Rueff, Jean-Pascal/0000-0003-3594-918X NR 14 TC 11 Z9 11 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAR PY 2000 VL 61 IS 3 BP 457 EP 460 DI 10.1016/S0022-3697(99)00336-4 PG 4 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 286XL UT WOS:000085474100026 ER PT J AU Emery, VJ Kivelson, SA AF Emery, VJ Kivelson, SA TI Charge inhomogeneity and high temperature superconductivity SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Workshop on Inelastic X-ray Scattering CY OCT 18-21, 1998 CL LONG ISL CITY, NEW YORK SP US DOE, Div Mat Sci, Argonne Natl Lab, Blake Ind, Brookhaven Natl Lab, Brookhaven Sci Assoc, Oak Ridge Natl Lab, Synchrotron Radiat Res Ctr DE superconductivity; charge inhomogeneity ID T-C SUPERCONDUCTORS; MUON SPIN ROTATION; PHASE-SEPARATION; FERMI-SURFACE; J MODEL; GAP ANISOTROPY; LA2-XSRXCUO4; BI2SR2CACU2O8+DELTA; ANTIFERROMAGNETS; LA1.85SR0.15CUO4 AB When charge is doped into a correlated insulator, it forms an inhomogeneous state which may be fluctuating, ordered or glassy. The outstandingly successful BCS theory of superconductivity was not designed for doped insulators, and an appropriate theory must incorporate the local electronic structure on the scale of the superconducting coherence length. Unlike conventional materials, superconductivity in the cuprates is driven by lowering the in-plane zero-point kinetic energy. There is extensive experimental evidence in support of this picture. Inelastic X-ray scattering can give information about the existence and energy scale of the charge structure, especially in optimally doped materials. (C) 2000 Published by Elsevier Science Ltd. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. RP Emery, VJ (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 51 TC 8 Z9 8 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAR PY 2000 VL 61 IS 3 BP 467 EP 471 DI 10.1016/S0022-3697(99)00338-8 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 286XL UT WOS:000085474100028 ER PT J AU Schwoerer-Bohning, M Macrander, AT AF Schwoerer-Bohning, M Macrander, AT TI Phonons in large-band-gap materials SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Workshop on Inelastic X-ray Scattering CY OCT 18-21, 1998 CL LONG ISL CITY, NEW YORK SP US DOE, Div Mat Sci, Argonne Natl Lab, Blake Ind, Brookhaven Natl Lab, Brookhaven Sci Assoc, Oak Ridge Natl Lab, Synchrotron Radiat Res Ctr DE phonons; large-band-gap materials; lattice dynamics ID NITRIDE SINGLE-CRYSTALS; ALUMINUM NITRIDE; LATTICE-DYNAMICS; ALN AB The outstanding thermal and chemical stability of large-band-gap materials like silicon carbide and III-V nitride semiconductors make them promising candidates for high-temperature electronics and short-wavelength optical applications. We present first studies of the phonon dispersion in hexagonal silicon carbide along the T-K-M direction and in hexagonal aluminum nitride along all three high-symmetry directions. Investigating the lattice dynamics of small single crystals (volume less than or equal to 1 mm(3)) has become feasible with the advent of high-resolution inelastic X-ray scattering. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Adv Photon Source, Carnegie Inst Washington, Argonne, IL 60439 USA. Argonne Natl Lab, Adv Photon Source, Expt Facil Div, Argonne, IL 60439 USA. RP Schwoerer-Bohning, M (reprint author), Argonne Natl Lab, Adv Photon Source, Carnegie Inst Washington, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 6 Z9 6 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAR PY 2000 VL 61 IS 3 BP 485 EP 487 DI 10.1016/S0022-3697(99)00341-8 PG 3 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 286XL UT WOS:000085474100031 ER PT J AU Liu, LC Ma, WH AF Liu, LC Ma, WH TI The xi(2230) meson and the pomeron trajectory SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Letter ID J/PSI RADIATIVE DECAYS; GLUEBALL; MODEL AB We examine the possibility that the xi(2230) meson is a member of the pomeron trajectory. A method of connecting the xi --> p (p) over bar decay width and the pp cross sections through the pomeron residue function is presented. We have used a relativistic, singularity-free form factor to make the analytic continuation of the residue function between crossed channels. We predict that if the xi(2230) meson is a pomeron, then it should have a xi --> p (p) over bar decay width of about 2 MeV. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Acad Sinica, Inst High Energy Phys, Beijing, Peoples R China. RP Liu, LC (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, T-2, Los Alamos, NM 87545 USA. NR 16 TC 14 Z9 17 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD MAR PY 2000 VL 26 IS 3 BP L59 EP L63 DI 10.1088/0954-3899/26/3/103 PG 5 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 297YR UT WOS:000086111200003 ER PT J AU Juutilainen, J Stevens, RG Anderson, LE Hansen, NH Kilpelainen, M Kumlin, T Laitinen, JT Sobel, E Wilson, BW AF Juutilainen, J Stevens, RG Anderson, LE Hansen, NH Kilpelainen, M Kumlin, T Laitinen, JT Sobel, E Wilson, BW TI Nocturnal 6-hydroxymelatonin sulfate excretion in female workers exposed to magnetic fields SO JOURNAL OF PINEAL RESEARCH LA English DT Article DE ELF; human; magnetic fields; melatonin; 6-OHMS; urine ID PINEAL-GLAND; MELATONIN PRODUCTION; PLASMA MELATONIN; RAILWAY WORKERS; SERUM MELATONIN; BREAST-CANCER; RATS AB The objective of this study was to determine whether daytime occupational exposure to extremely low frequency magnetic fields (MFs) suppresses nocturnal melatonin production. Sixty female volunteers were recruited. Thirty-nine worked in a garment factory, and 21 office workers served as a reference group. Exposure assessment was based on the type of sewing machine used and MF measurements around each type of machine. Eye-level MF flux density was used to classify the operators to higher (> 1 mu T) and lower (0.3-1 mu T) exposure categories. A third group of factory workers had diverse MF exposures from other sources. The reference group had average exposure of about 0.15 mu T. Urine samples were collected on Friday and Monday for three consecutive weeks. Melatonin production was assessed as urinary 6-hydroxymelatonin sulfate (6-OHMS) excretion. The ratio of Friday morning/Monday morning 6-OHMS was used to test the hypothesis that melatonin production is suppressed after 4 days of occupational MF exposure with significant recovery during the weekend. Possible chronic suppression of melatonin production was evaluated by studying exposure-related differences in the Friday values by multivariate regression analysis. The Monday/Friday ratios were close to 1.0, suggesting that there is no increase in melatonin production over the weekend. The average 6-OHMS excretion on Friday was lower among the factory workers than in the reference group, but no monotonous dose-response was observed. Multivariate regression analysis identified MF exposure, smoking, and age as significant explanatory variables associated with decreased 6-OHMS excretion. C1 Univ Kuopio, Dept Environm Sci, FIN-70211 Kuopio, Finland. Univ Kuopio, Dept Physiol, FIN-70211 Kuopio, Finland. Pacific NW Lab, Richland, WA USA. Univ So Calif, Sch Med, Los Angeles, CA USA. RP Juutilainen, J (reprint author), Univ Kuopio, Dept Environm Sci, POB 1627, FIN-70211 Kuopio, Finland. EM jukka.juutilainen@uku.fi NR 35 TC 34 Z9 37 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0742-3098 J9 J PINEAL RES JI J. Pineal Res. PD MAR PY 2000 VL 28 IS 2 BP 97 EP 104 DI 10.1034/j.1600-079X.2001.280205.x PG 8 WC Endocrinology & Metabolism; Neurosciences; Physiology SC Endocrinology & Metabolism; Neurosciences & Neurology; Physiology GA 287NQ UT WOS:000085512500005 PM 10709971 ER PT J AU Chalk, SG Miller, JF Wagner, FW AF Chalk, SG Miller, JF Wagner, FW TI Challenges for fuel cells in transport applications SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 6th Grove Fuel Cell Symposium Fuel Cells - The Competitive Option for Sustainable Energy Supply CY SEP 13-16, 1999 CL LONDON, ENGLAND SP Queen Elizabeth II Conference Ctr DE US Department of Energy (DOE); Partnership for a New Generation of Vehicles (PNGV); polymer electrolyte membrane (PEM) fuel cells; fuel cell stack; fuel processing AB The US Department of Energy (DOE) and the US automotive industry are working cooperatively under the auspices of the Partnership for a New Generation of Vehicles (PNGV) to develop a six-passenger automobile that can achieve up to 80 miles/gal. These partners are continuing to invest heavily in research and development of polymer electrolyte membrane (PEM) fuel cells as a clean and efficient alternative technology for transport applications. In the past few years, US automakers have made significant advances in fuel cell technology and have announced plans to put fuel cell vehicles on the market by 2004. DOE is working with industry suppliers to address some of the biggest remaining challenges, which include fuel processing and lowering the cost of fuel cell systems. The refueling infrastructure necessary to support fuel cell vehicles presents additional unresolved issues. This paper provides a status report on the PNGV program and provides an overview of the technical accomplishments and future plans of the DOE Fuel Cells for Transportation Program. (C) 2000 Elsevier Science S.A. All rights reserved. C1 US DOE, Off Adv Automot Technol, Washington, DC 20585 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Energetics, Columbia, MD USA. RP Chalk, SG (reprint author), US DOE, Off Adv Automot Technol, 1000 Independence Ave SW, Washington, DC 20585 USA. NR 6 TC 96 Z9 105 U1 2 U2 13 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0378-7753 J9 J POWER SOURCES JI J. Power Sources PD MAR PY 2000 VL 86 IS 1-2 BP 40 EP 51 DI 10.1016/S0378-7753(99)00481-4 PG 12 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 305KE UT WOS:000086538200008 ER PT J AU Ren, XM Zelenay, P Thomas, S Davey, J Gottesfeld, S AF Ren, XM Zelenay, P Thomas, S Davey, J Gottesfeld, S TI Recent advances in direct methanol fuel cells at Los Alamos National Laboratory SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 6th Grove Fuel Cell Symposium Fuel Cells - The Competitive Option for Sustainable Energy Supply CY SEP 13-16, 1999 CL LONDON, ENGLAND SP Queen Elizabeth II Conference Ctr DE direct methanol fuel cell; transport application; portable power application; methanol crossover ID ELECTROLYTE AB This paper describes recent advances in the science and technology of direct methanol fuel cells (DMFCs) made at Los Alamos National Laboratory (LANL). The effort on DMFCs at LANL includes work devoted to portable power applications, funded by the Defense Advanced Research Project Agency (DARPA), and work devoted, to potential transport applications, funded by the US DOE. We describe recent results with a new type of DMFC stack hardware that allows to lower the pitch per cell to 2 mm while allowing low air flow and air pressure drops. Such stack technology lends itself to both portable power and potential transport applications. Power densities of 300 W/1 and 1 kW/1 seem achievable under conditions applicable to portable power and transport applications, respectively. DMFC power system analysis based on the performance of this stack, under conditions applying to transport applications (joint effort with U.C. Davis), has shown that, in terms of overall system efficiency and system packaging requirements, a power source for a passenger vehicle based on a DMFC could compete favorably with a hydrogen-fueled fuel cell system, as well as with fuel cell systems based on fuel processing on board. As part of more fundamental studies performed, we describe optimization of anode catalyst layers in terms of PtRu catalyst nature, loading and catalyst layer composition and structure. We specifically show that, optimized content of recast ionic conductor added to the catalyst layer is a sensitive, function of the nature of the catalyst. Other elements of membrane/electrode assembly (MEA) optimization efforts are also described, highlighting our ability to resolve, to a large degree, a well-documented problem of polymer electrolyte DMFCs, namely "methanol crossover". This was achieved by appropriate cell design, enabling fuel utilization as high as 90% in highly performing DMFCs. (C) 2000 Elsevier Science S.A. An rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ren, XM (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI ren, xiaoming/F-3953-2011 NR 7 TC 536 Z9 577 U1 8 U2 91 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0378-7753 J9 J POWER SOURCES JI J. Power Sources PD MAR PY 2000 VL 86 IS 1-2 BP 111 EP 116 DI 10.1016/S0378-7753(99)00407-3 PG 6 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 305KE UT WOS:000086538200017 ER PT J AU Bauche, J Bauche-Arnoult, C Bachelier, A Palmeri, P Fournier, KB Goldstein, WH AF Bauche, J Bauche-Arnoult, C Bachelier, A Palmeri, P Fournier, KB Goldstein, WH TI Interpretation of atomic transition arrays generated by far-configuration interaction SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID X-RAY-SPECTRUM; LINES; TOKAMAK AB It is known that some radiative transition arrays, between configurations of opposite parities, are forbidden when the configurations are pure, and allowed when they are perturbed by configuration interaction. A method is described for computing the total strengths of such arrays, through the use of compact formulas, when the perturbing and the perturbed configurations lie far apart in energy. Numerical applications to the MoXVI spectrum are compared with the results of detailed line-by-line calculations. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 CNRS, Aime Cotton Lab, F-91405 Orsay, France. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Bauche-Arnoult, C (reprint author), CNRS, Aime Cotton Lab, Campus Orsay,Batiment 505, F-91405 Orsay, France. NR 13 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD MAR PY 2000 VL 64 IS 6 BP 549 EP 561 DI 10.1016/S0022-4073(99)00129-6 PG 13 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 277YP UT WOS:000084961400001 ER PT J AU Olson, GL Auer, LH Hall, ML AF Olson, GL Auer, LH Hall, ML TI Diffusion, P-1 and other approximate forms of radiation transport SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE time-dependent radiation transport; diffusion; P-1 approximation; P-1/3 approximation; radiation transport; flux-limited diffusion; Eddington factors AB Full transport solutions of time-dependent problems can be:computationally very expensive. Therefore, considerable effort has been devoted to developing approximate solution techniques that are much faster computationally and yet are accurate enough for a particular application. Many of these approximate solutions have been used in isolated problems and have not been compared to each other. This paper presents two test problems that test and compare several approximate transport techniques. In addition to the diffusion and P-1 approximations, we will test several different flux-limited diffusion theories and variable Eddington factor closures, For completeness, we will show some variations that have not yet appeared in the literature that have some interesting consequences, For example, we have found a trivial way to modify the P-1 equations to get the correct propagation velocity of a radiation front in the optically thin limit without modifying the accuracy of the solution in the optically thick limit, Also, we will demonstrate nonphysical behavior in some published techniques. (C) 1999 Elsevier Science Ltd, All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Transport Methods Grp, Los Alamos, NM 87545 USA. RP Olson, GL (reprint author), Univ Calif Los Alamos Natl Lab, Transport Methods Grp, POB 1663,MS D409, Los Alamos, NM 87545 USA. NR 11 TC 63 Z9 65 U1 0 U2 5 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 MAR PY 2000 VL 64 IS 6 BP 619 EP 634 DI 10.1016/S0022-4073(99)00150-8 PG 16 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 277YP UT WOS:000084961400006 ER PT J AU Paruelo, JM Lauenroth, WK Roset, PA AF Paruelo, JM Lauenroth, WK Roset, PA TI Technical note: Estimating aboveground plant biomass using a photographic technique SO JOURNAL OF RANGE MANAGEMENT LA English DT Article DE ANPP estimation; non-destructive methods; semiarid grassland ID PRODUCTIVITY; GRASSLANDS; STEPPE AB We present a non-destructive, photographic method to estimate biomass in semiarid grasslands. Though the method needs to be calibrated, it allows for a dramatic increase in the number of samples compared with the clipping method. The method is based on a relationship between the percentage of "green pixels" in a digital image and green biomass, We identified "green pixels" as those satisfying the following condition: G/B > 1 and G/R > 1, where G, B and R are the intensities of a particular pixel in the green, blue, and red bands respectively. The percentage of green pixels of the image and green grass biomass showed a correlation of 0.87 (n = 36, p < 0.001) when data were pooled from 3 sample dates, The relationship was slightly curvilinear and a log transformation of green biomass yielded a better correlation (r = 0.91, n = 36, p < 0.001), The percentage of green pixels showed a lower correlation with total green biomass than with grass biomass (r = 0.59 for the linear model and 0.73 for the log transformed model). The relationship between the percentage of green pixels and either green grass or total green biomass changed during the growing season. Both the slope and the Y-intercept of the model differed significantly among dates. Correlation coefficients for different dates ranged between 0.76 and 0.95. C1 Univ Buenos Aires, Fac Agron, Dept Ecol, IFEVA, RA-1417 Buenos Aires, DF, Argentina. Colorado State Univ, NREL, Ft Collins, CO 80523 USA. Colorado State Univ, Dept Rangeland Ecosyst Sci, Ft Collins, CO 80523 USA. RP Paruelo, JM (reprint author), Univ Buenos Aires, Fac Agron, Dept Ecol, IFEVA, Av San Martin 4453, RA-1417 Buenos Aires, DF, Argentina. NR 24 TC 30 Z9 34 U1 2 U2 8 PU SOC RANGE MANAGEMENT PI LAKEWOOD PA 445 UNION BLVD, STE 230, LAKEWOOD, CO 80228-1259 USA SN 0022-409X J9 J RANGE MANAGE JI J. Range Manage. PD MAR PY 2000 VL 53 IS 2 BP 190 EP 193 DI 10.2307/4003281 PG 4 WC Agriculture, Dairy & Animal Science; Ecology SC Agriculture; Environmental Sciences & Ecology GA 337MT UT WOS:000088365900009 ER PT J AU Edwards, DD Mason, TO Sinkler, W Marks, LD Poeppelmeier, KR Hu, Z Jorgensen, JD AF Edwards, DD Mason, TO Sinkler, W Marks, LD Poeppelmeier, KR Hu, Z Jorgensen, JD TI Tunneled intergrowth structures in the Ga2O3-In2O3-SnO2 system SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID ELECTRON-DIFFRACTION AB The structures of several Ga2O3-In2O3-SnO2 phases were investigated using high-resolution electron microscopy, X-ray diffraction, and Rietveld analysis of time-of-flight neutron diffraction data. The phases, expressed as Ga(4-4)xIn(4x)Sn(n-4)O(2n-2) (n = 6 and 7-17, odd), are intergrowths between the beta-gallia structure of (Ga, In)(2)O-3 and the rutile structure of SnO2. Samples prepared with n greater than or equal to 9 crystallize in C2/m and are isostructural with intergrowths in the Ga2O3TiO2 system. Samples prepared with n = 6 and n = 7 are members of an alternative intergrowth series that crystallizes in P2/m, Both intergrowth series are similar in that their members possess 1-D tunnels along the b axis. The difference between the two series is described in terms of different crystallographic sheer plane operations (CSP) on the parent futile structure. (C) 2000 Academic Press. C1 Alfred Univ, New York State Coll Ceram, Dept Ceram Engn & Mat Sci, Alfred, NY 14802 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Argonne Natl Lab W, Idaho Falls, ID 83403 USA. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Edwards, DD (reprint author), Alfred Univ, New York State Coll Ceram, Dept Ceram Engn & Mat Sci, Alfred, NY 14802 USA. RI Mason, Thomas/B-7528-2009; Marks, Laurence/B-7527-2009 NR 17 TC 16 Z9 17 U1 0 U2 9 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 MAR PY 2000 VL 150 IS 2 BP 294 EP 304 DI 10.1006/jssc.1999.8594 PG 11 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 295PY UT WOS:000085978100008 ER PT J AU Richter, KW Franzen, HF AF Richter, KW Franzen, HF TI Structure-composition relations and fractional site occupancy of new M5Ge4 compounds in the system Ge-Ta-Zr SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article DE tantalum zirconium germanides; crystal structure; bonding; disorder; differential fractional site occupancy ID CRYSTAL-STRUCTURE; TERNARY; STABILIZATION; PHOSPHIDES; GERMANIDES; SULFIDES; TANTALUM; NIOBIUM AB The new ternary phases Zr4-xTa1+xGe4 (0.1 i + 4 residues (DpSpSEEKFLRRIGRFG) using rotational echo double resonance (REDOR). Peptides singly labeled at amino acids pS(3), L-8, and G(12) were used for relaxation and line width measurements. The peptides adsorbed to the HAP surface have an average phi of -85 degrees at the N-terminus (pSpS), -60 degrees in the middle (FL) and -73 degrees near the C-terminus (IG). The average phi angle measured at the pSpS position and the observed high conformational dispersion suggest a random coil conformation at this position. However, the FL position displays an average phi that indicates significant alpha-helical content, and the long time points in the DRAWS experiment fit best to a relatively narrow distribution of phi that falls within the protein data bank alpha-helical conformational space. REDOR measurements confirm the presence of helical content, where the distance across the LG hydrogen bond of the adsorbed peptide has been found to be 5.0 Angstrom. The phi angle measured at the IG position falls at the upper end of the protein data bank alpha-helical distribution, with a best fit to a relatively broad phi distribution that is consistent with a distribution of alpha-helix and more extended backbone conformation. These results thus support a structural model where the N-terminus is disordered, potentially to maximize interactions between the HAP surface and the negatively charged side chains found in this region, the middle portion is largely alpha-helical, and the C-terminus has a more extended conformation (or a mixture of helix and extended conformations). C1 Univ Washington, Dept Bioengn, Seattle, WA 98195 USA. Univ Washington, Dept Chem, Seattle, WA 98195 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Stayton, PS (reprint author), Univ Washington, Dept Bioengn, Box 352125, Seattle, WA 98195 USA. NR 58 TC 72 Z9 75 U1 5 U2 22 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 MAR 1 PY 2000 VL 122 IS 8 BP 1709 EP 1716 DI 10.1021/ja9842823 PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA 289NV UT WOS:000085629600018 ER PT J AU Klei, SR Tilley, TD Bergman, RG AF Klei, SR Tilley, TD Bergman, RG TI The mechanism of silicon-hydrogen and carbon-hydrogen bond activation by iridium(III): Production of a silylene complex and the first direct observation of Ir(III)/Ir(V) C-H bond oxidative addition and reductive elimination SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID METAL-COMPLEXES; STABILIZATION; GENERATION; PLATINUM; METHANE C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Tilley, TD (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 25 TC 118 Z9 118 U1 2 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD MAR 1 PY 2000 VL 122 IS 8 BP 1816 EP 1817 DI 10.1021/ja992954z PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 289NV UT WOS:000085629600036 ER PT J AU McCandlish, CA McMahon, JM Todd, PJ AF McCandlish, CA McMahon, JM Todd, PJ TI Secondary ion images of the rodent brain SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID TANDEM MASS-SPECTROMETRY; IDENTIFICATION AB Sections of biologic tissue obtained from laboratory rodents are prepared and analyzed by secondary ion mass spectrometry. The intensity of phosphocholine secondary ions is used to identify anatomical features of the brain from secondary ion images and to evaluate the effectiveness of procedures developed. Secondary ion emission of phosphocholine (m/z 184), is found to be abundant and its intensity is heterogeneous. Effects of sample thickness are addressed. Correspondence between conventional optical images of stained tissue and secondary ion images shows that successive ion images may be used to produce a three-dimensional map of the brain, i.e., an atlas. (C) 2000 American Society for Mass Spectrometry. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Todd, PJ (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008,Bldg 5510A, Oak Ridge, TN 37831 USA. FU NIGMS NIH HHS [R01-GM41617] NR 29 TC 23 Z9 23 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD MAR PY 2000 VL 11 IS 3 BP 191 EP 199 DI 10.1016/S1044-0305(99)00145-2 PG 9 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 285NW UT WOS:000085396000001 PM 10697814 ER PT J AU Maier, CS Yan, XG Harder, ME Schimerlik, MI Deinzer, ML Pasa-Tolic, L Smith, RD AF Maier, CS Yan, XG Harder, ME Schimerlik, MI Deinzer, ML Pasa-Tolic, L Smith, RD TI Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometric analysis of the recombinant human macrophage colony stimulating factor beta and derivatives SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID INFRARED MULTIPHOTON DISSOCIATION; ESCHERICHIA-COLI; PROTEINS; PURIFICATION; ASSIGNMENT; CLEAVAGE AB The potential of electrospray ionization (ESI) Fourier transform ion cyclotron mass spectrometry (FTICR-MS) to assist in the structural characterization of monomeric and dimeric derivatives of the macrophage colony stimulating factor beta (rhM-CSF beta) was assessed. Mass spectrometric analysis of the 49 kDa protein required the use of sustained off-resonance irradiation (SORT) in-trap cleanup to reduce adduction. High resolution mass spectra were acquired for a fully reduced and a fully S-cyanylated monomeric derivative (similar to 25 kDa). Mass accuracy for monomeric derivatives was better than 5 ppm, after applying a new calibration method (i.e., DeCAL) which eliminates space charge effects upon high accuracy mass measurements. This high mass accuracy allowed the direct determination of the exact number of incorporated cyanyl groups. Collisionally induced dissociation using SORI yielded b- and y-fragment ions within the N- and C-terminal regions for the monomeric derivatives, but obtaining information on other regions required proteolytic digestion, or potentially the use of alternative dissociation methods. (C) 2000 American Society for Mass Spectrometry. C1 Oregon State Univ, Dept Chem, Corvallis, OR 97331 USA. Oregon State Univ, Dept Biochem & Biophys, Corvallis, OR 97331 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA USA. RP Deinzer, ML (reprint author), Oregon State Univ, Dept Chem, Gilbert Hall 153, Corvallis, OR 97331 USA. RI Harder, Mark/A-7142-2009; Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 FU NCEH CDC HHS [NIEHS 00040] NR 32 TC 13 Z9 14 U1 0 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD MAR PY 2000 VL 11 IS 3 BP 237 EP 243 DI 10.1016/S1044-0305(99)00139-7 PG 7 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 285NW UT WOS:000085396000006 PM 10697819 ER PT J AU Lee, YJ Wang, F Mukerjee, S McBreen, J Grey, CP AF Lee, YJ Wang, F Mukerjee, S McBreen, J Grey, CP TI Li-6 and Li-7 magic-angle spinning nuclear magnetic resonance and in situ X-ray diffraction studies of the charging and discharging of LixMn2O4 at 4 V SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID RECHARGEABLE LITHIUM BATTERIES; CATHODE MATERIALS; SPINEL PHASE; ELECTROCHEMICAL CHARACTERIZATION; STRUCTURE REFINEMENT; PECHINI PROCESS; ION BATTERIES; LIMN2O4; INSERTION; OXIDES AB Li-6 and Li-7 magic-angle spinning (MAS) nuclear magnetic resonance (NMR) and in situ X-ray diffraction (XRD) have been used to study lithium manganate cathode materials (LixMn2O4, 0 < x less than or equal to 1) during and following charging and discharging. Only one major local environment is observed by 6Li MAS NMR from 0 to 1 50% charging from lithium in the tetrahedral sites of the spinel structure, the resonance shifting by no more than 8 ppm in this range (from its original position at ca. 520 ppm). When the cell is charged above 50%, a new resonance is observed at approximate to 645 ppm, due to Li+ in a spinel local environment with nearby manganese ions in oxidation states close to +4 (e.g., in a composition such as Li0.1Mn2O4). The two resonances at approximate to 520 and 645 ppm are both observed in the range 70 to <80 and 80 to 90% for the samples annealed at 850 and 650 degrees C, respectively. These coexistences occur over the same ranges as the two-phase coexistence, as observed by XRD during the first charging cycle. Resonances were observed at 830 and 930 ppm,,for the samples annealed at 650 and 850 degrees C. respectively, at greater than or equal to 90% charging. These same resonances were seen after multiple charging cycles and are assigned to defect spinels with high manganese oxidation states. Additional resonances are observed for electrodes with high carbon contents at -2 to -13 ppm, from nonspinel phases, which grow in intensity with the number of charging cycles. The presence of the defect spinels and the additional impurity phases contribute to the reduced capacity of these materials. Three-phase behavior is observed by in situ XRD during the first discharging cycle. These results are discussed in terms of previous in situ XRD charging/discharging results. (C) 2000 The Electrochemical Society. S0013-4651(99)05-031-4. All rights reserved. C1 SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. Northeastern Univ, Dept Chem, Boston, MA 02115 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11793 USA. RP Lee, YJ (reprint author), SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. OI Lee, Young Joo/0000-0002-5782-6431 NR 54 TC 55 Z9 56 U1 3 U2 38 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 MAR PY 2000 VL 147 IS 3 BP 803 EP 812 DI 10.1149/1.1393276 PG 10 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 294LL UT WOS:000085912700001 ER PT J AU Dunn, D Newman, J AF Dunn, D Newman, J TI Predictions of specific energies and specific powers of double-layer capacitors using a simplified model SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ACTIVATED CARBONS; ELECTRODE AB A model based on dilute-solution porous-electrode theory is proposed to describe electrochemical devices that store energy in the double layer (double-layer capacitors). Various assumptions, such as neglecting concentration polarization, potential-dependent capacitance, and micropore effects, are made in the model. For constant-current discharges, the model reduces to a resistance-capacitance (RC) series circuit model after the initial discharging transients. The RC series circuit model is seen to fit existing experimental data for the discharge times available. The specific energy for constant-current and constant-power discharges is maximized over a range of discharge times by optimizing the electrode thickness, electrode porosity, and the final voltage constrained by the cutoff voltage. This maximization allows predictions of the attainable specific energies and powers for these devices and shows the influence of the various cell properties. Energy efficiencies are found for cycles when the capacitor is discharged in a given time and then charged infinitely slowly, and when the capacitor is discharged and charged in the same amount of time. Limitations to the model are discussed. (C) 2000 The Electrochemical Society. S0013-4651(99)05-100-9. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Dunn, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RI Newman, John/B-8650-2008 OI Newman, John/0000-0002-9267-4525 NR 20 TC 38 Z9 38 U1 3 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 MAR PY 2000 VL 147 IS 3 BP 820 EP 830 DI 10.1149/1.1393278 PG 11 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 294LL UT WOS:000085912700003 ER PT J AU Mansour, AN Mukerjee, S Yang, XQ McBreen, J AF Mansour, AN Mukerjee, S Yang, XQ McBreen, J TI In situ X-ray absorption and diffraction study of the Li reaction with a tin composite oxide glass SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID LITHIUM AB We have measured the X-ray absorption fine structure spectra of a sample of tin-based composite oxide (TCO) material with a nominal composition of Sn1.0B0.56P0.40Al0.42O3.47 during the discharge and charge cycles in an in situ configuration. Our results confirm the amorphous nature of TCO material and show that Sn in the pristine state of TCO is coordinated with three oxygen atoms at a distance of 2.12 a. Upon discharging, initially LE interacts with the electrochemically active Sn-O center, forming metallic Sn in a highly dispersed form (i.e., clusters containing just a few atoms). Upon further discharge, Li alloys with Sn, forming highly dispersed forms of Li,Sn alloys with x being dependent on the degree of Li intercalation. The structural nature of the highly dispersed alloys differs from those of the corresponding crystalline phases such as Li2Sn5, LiSn, Li7Sn3, Li5Sn2, Li13Sn5, and Li7Sn2. Upon charging, Li dealloys from Li,Sn, forming metallic Sn in a highly dispersed form with a Sn-Sn distance intermediate to those of gray and white Sn. (C) 2000 The Electrochemical Society. S0013-4651(99)04-108-5. All rights reserved. C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. Northeastern Univ, Dept Chem, Boston, MA 02115 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. EM MansourAN@nswccd.navy.mil NR 19 TC 19 Z9 20 U1 0 U2 6 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 EI 1945-7111 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAR PY 2000 VL 147 IS 3 BP 869 EP 873 DI 10.1149/1.1393284 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 294LL UT WOS:000085912700009 ER PT J AU Schoeler, AC Kaun, TD Bloom, I Lanagan, M Krumpelt, M AF Schoeler, AC Kaun, TD Bloom, I Lanagan, M Krumpelt, M TI Corrosion behavior and interfacial resistivity of bipolar plate materials under molten carbonate fuel cell cathode conditions SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID HIGH-ALLOY STEELS; IRON; NI AB A material is needed for bipolar plate materials in molten carbonate fuel cells (MCFCs) that combines the low oxide resistivity of 316L stainless steel (SS) with the low corrosion rate of the type 310 SS. We tested a group of materials that included Nitronic 50 SS and a newly developed high-temperature nickel-rich alloy, having chromium contents ranging from 16 to 31 wt %. Our results indicate that chromium content is the primary determinant of oxide scale composition and resistivity. In the MCFC cathode compartment, all tested alloys formed a duplex structure with an inner Cr-rich layer and an outer Fe-rich one. The composition of the inner Cr-rich layer was determined by the chromium content of the base alloy and has a controlling effect on scale resistivity. Oxide scale resistivity was measured for three electrolyte compositions: Li/K, Li/Na, and newly developed (Li, Na, Ca, Ba) carbonates. Changes in the physical/mechanical properties (spallation/cracking): in the oxide scale of 316L SS provided an understanding of its resistivity fluctuations over time. (C) 2000 The Electrochemical Society. S0013-4651(99)04-004-5. AU rights reserved. C1 Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, Argonne, IL 60439 USA. RP Schoeler, AC (reprint author), Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 23 TC 10 Z9 10 U1 1 U2 3 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 MAR PY 2000 VL 147 IS 3 BP 916 EP 921 DI 10.1149/1.1393292 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 294LL UT WOS:000085912700017 ER PT J AU Kim, JC Auh, KH Schilling, CH AF Kim, JC Auh, KH Schilling, CH TI Effects of polysaccharides on the rheology of alumina slurries SO JOURNAL OF THE EUROPEAN CERAMIC SOCIETY LA English DT Article DE Al2O3; polysaccharides; rheology; suspensions ID PARTICLE PACKING; HYDRATION FORCES; CONSOLIDATION; SUSPENSIONS; POTENTIALS; BEHAVIOR; SURFACES; AL2O3; DLVO AB The rheological behaviors of alumina slurries with polysaccharides having different concentrations and molecular weights were analyzed. The polysaccharide molecule absorbs to the surface of alumina powder in an aqueous slurry to give sorbate-mediated steric hindrance. Rheological measurements were used to compare the strength of alumina particulate networks. The network strength of alumina slurry increased at first and decreased later with the increase of molecular weight of polysaccharides. The network strength of alumina slurry became weaker with the addition of polysaccharides of low molecular weight and stronger with the addition of polysaccharides of higher molecular weight. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Hanyang Univ, Ceram Mat Res Inst, Seoul 133791, South Korea. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Kim, JC (reprint author), Hanyang Univ, Ceram Mat Res Inst, Seoul 133791, South Korea. NR 23 TC 14 Z9 14 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0955-2219 J9 J EUR CERAM SOC JI J. European Ceram. Soc. PD MAR PY 2000 VL 20 IS 3 BP 259 EP 266 DI 10.1016/S0955-2219(99)00168-5 PG 8 WC Materials Science, Ceramics SC Materials Science GA 282FT UT WOS:000085207900004 ER PT J AU Landis, CM Beyerlein, IJ McMeeking, RM AF Landis, CM Beyerlein, IJ McMeeking, RM TI Micromechanical simulation of the failure of fiber reinforced composites SO JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS LA English DT Article DE fiber-reinforced composite material; stress concentrations; fracture mechanisms; probability and statistics; shear lag ID SINGLE-FILAMENT COMPOSITE; BUNDLES PROBABILITY MODEL; WEIBULL FIBERS; INFLUENCE SUPERPOSITION; MATRIX COMPOSITES; FIBROUS MATERIALS; STRENGTH; FRAGMENTATION; STATISTICS; FRACTURE AB The strength of unidirectionally reinforced fiber composites is simulated using the three dimensional shear lag model of Landis, C. M., McGlockton, M. A. and McMeeking, R. M. (1999) (An improved shear lag model for broken fibers in composites. J. Comp. Mat. 33, 667-680) and Weibull fiber statistics. The governing differential equations for the fiber displacements and stresses are solved exactly for any configuration of breaks using an influence superposition technique. The model predicts the tensile strength of well bonded, elastic fiber/matrix systems with fibers arranged in a square array. Length and strength scalings are used which are relevant for elastic, local load sharing composites. Several hundred Monte Carlo simulations were executed to determine the statistical strength distributions of the composite for three values of the fiber Weibull modulus, m = 5, 10 and 20. Stress-strain behavior and the evolution of fiber damage are studied. Bundle sizes of 10 x 10, 15 x 15, 20 x 20, 25 x 25, 30 x 30 and 35 x 35 fibers of various lengths are investigated to determine the dependence of strength on the composite size. The validity of weakest link statistics for composite strength is examined as well. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Univ Calif Santa Barbara, Dept Mech & Environm Engn, Santa Barbara, CA 93106 USA. RP Landis, CM (reprint author), Harvard Univ, Div Engn & Appl Sci, Pierce Hall, Cambridge, MA 02138 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 24 TC 98 Z9 106 U1 5 U2 21 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-5096 J9 J MECH PHYS SOLIDS JI J. Mech. Phys. Solids PD MAR PY 2000 VL 48 IS 3 BP 621 EP 648 DI 10.1016/S0022-5096(99)00051-4 PG 28 WC Materials Science, Multidisciplinary; Mechanics; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 282GT UT WOS:000085210400009 ER PT J AU Mulholland, PJ Tank, JL Sanzone, DM Wollheim, WM Peterson, BJ Webster, JR Meyer, JL AF Mulholland, PJ Tank, JL Sanzone, DM Wollheim, WM Peterson, BJ Webster, JR Meyer, JL TI Food resources of stream macroinvertebrates determined by natural-abundance stable C and N isotopes and a N-15 tracer addition SO JOURNAL OF THE NORTH AMERICAN BENTHOLOGICAL SOCIETY LA English DT Article DE stream macroinvertebrates; food resources; N cycling; tracer addition; stable isotope; N-15; C-13 ID WOODLAND STREAM; LABORATORY STREAMS; CARBON-ISOTOPE; TUNDRA RIVER; ECOSYSTEM; WEB; PERIPHYTON; DYNAMICS AB Trophic relationships were examined using natural-abundance C-13 and N-15 analyses and a N-15-tracer addition experiment in Walker Branch a Ist-order forested stream in eastern Tennessee. In the N-15-tracer addition experiment we added (NH4)-N-15 to stream water over a 6-wk period in early spring, and measured N-15:N-14 ratios in different taxa and biomass compartments over distance and time. Samples collected from a station upstream from the N-15 addition provided data on natural-abundance C-13:C-12 and N-15:N-14 ratios. The natural abundance N-15 analysis proved to be of Limited value in identifying food resources of macroinvertebrates because N-15 values were not greatly different among food resources. In general, the natural-abundance stable isotope approach was most useful for determining whether epilithon or detritus were important food resources for organisms that may use both (e.g., the snail Elimia clavaeformis), and to provide corroborative evidence of food resources of tara for which the N-15 tracer results were not definitive. The N-15 tracer results showed that the mayflies Stenonema spp. and Baetis spp. assimilated primarily epilithon, although Baetis appeared to assimilate a portion of the epilithon (e.g., algal cells) with more rapid N turnover than the bulk pool sampled. Although Elimia did not reach isotopic equilibrium during the tracer experiment, application of a N-turnover model to the field data suggested that it assimilated a combination of epilithon and detritus. The amphipod Gammarus minus appeared to depend mostly on fine benthic organic matter (FBOM), and the coleopteran Anchytarsus bicolor on epixylon. The caddisfly Diplectrona modesta appeared to assimilate primarily a fast N-turnover portion of the FBOM pool, and Simuliidae a fast N-turnover component of the suspended particulate organic matter pool rather than the bulk pool sampled. Together, the natural-abundance stable C and N isotope analyses and the experimental N-15 tracer approach proved to be very useful tools for identifying food resources in this stream ecosystem. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Illinois, Dept Nat Resources & Environm Sci, Urbana, IL 61801 USA. Univ Georgia, Inst Ecol, Athens, GA 30602 USA. Marine Biol Lab, Ctr Ecosyst, Woods Hole, MA 02543 USA. Virginia Polytech Inst & State Univ, Dept Biol, Blacksburg, VA 24061 USA. RP Mulholland, PJ (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. EM mulhollandpj@ornl.gov RI Mulholland, Patrick/C-3142-2012 NR 29 TC 47 Z9 47 U1 1 U2 35 PU NORTH AMER BENTHOLOGICAL SOC PI LAWRENCE PA 1041 NEW HAMSPHIRE STREET, LAWRENCE, KS 66044 USA SN 0887-3593 J9 J N AM BENTHOL SOC JI J. N. Am. Benthol. Soc. PD MAR PY 2000 VL 19 IS 1 BP 145 EP 157 DI 10.2307/1468287 PG 13 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 317BM UT WOS:000087205700010 ER PT J AU Sze, RC Smith, CA AF Sze, RC Smith, CA TI High-temperature absorption studies of the Schumann-Runge band of oxygen at ArF laser wavelengths SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID EXCIMER-LASER AB The possibility of a simple single-shot oxygen monitor for a float-glass plant by use of the Schumann-Runge absorption lines within the broadband lasing structure of an ArF excimer laser initiated this detailed study. We present the theoretical predictions and the experimental absorption profiles at temperatures from 76 to 2000 degrees F. Laboratory experiments predict that detection of a few to ten parts per million of oxygen in the float section of the plant is doable. (C) 2000 Optical Society of America [S0740-3224(00)01603-9] OCIS codes: 300.0300, 300.6210. C1 Univ Calif Los Alamos Natl Lab, Grp CST 6, Los Alamos, NM 87545 USA. PPG Ind Inc, Glass Technol Ctr, Pittsburgh, PA 15238 USA. RP Sze, RC (reprint author), Univ Calif Los Alamos Natl Lab, Grp CST 6, MS E535, Los Alamos, NM 87545 USA. NR 11 TC 1 Z9 1 U1 0 U2 2 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 MAR PY 2000 VL 17 IS 3 BP 462 EP 475 DI 10.1364/JOSAB.17.000462 PG 14 WC Optics SC Optics GA 294MY UT WOS:000085916100015 ER PT J AU Kimura, H Hirota, K Lee, CH Yamada, K Shirane, G AF Kimura, H Hirota, K Lee, CH Yamada, K Shirane, G TI Structural instability associated with the tilting of CuO6 octahedra in La2-xSrxCuO4 SO JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN LA English DT Article DE La2-xSrxCuO4; soft phonons; incommensurate structural diffuse peak ID INELASTIC-NEUTRON-SCATTERING; SINGLE-CRYSTAL LA2-XSRXCUO4; PHASE-TRANSITION; SUPERCONDUCTING-TRANSITION; LATTICE INSTABILITY; OXYGEN DEFICIENCY; LA1.85SR0.15CUO4; TEMPERATURE; DEPENDENCE; TRANSPORT AB Comprehensive inelastic neutron-scattering measurements were performed to study the soft optical phonons in La2-xSrxCuO4 at x = 0.10, 0.12 and 0.18. We found at x = 0.18 that the softening of Z-point phonon, suggesting incipient structural transition from the low-temperature orthorhombic (LTO) to low-temperature tetragonal (LTT) phase, breaks at T-c, which is consistent with the previous report by Lee et al. for the optimally doped x = 0.15 sample. As for x = 0.10 and 0.12, on the other hand, the softening continues even below T-c. It is thus clarified that the breaking of soft phonon is characteristic of La2-xSrxCuO4 in the optimally and overdoped regions. In the course of studying the soft phonons, we discovered that a central peak remains above the LTO to high-temperature tetragonal (HTT) phase transition at T-s1 and splits into incommensurate components along title [1 1 0](HTT) direction at higher temperatures. This is a common feature for both x = 0.12 and 0.18 and their temperature dependences of the splitting 2 delta can be scaled by using a renormalized temperature T/T-s1. In the high temperature limit, delta saturates around delta similar to 0.12 r.l.u., which value is close to the splitting of incommensurate magnetic signals. This implies that the incipient lattice modulation starts appearing at very high temperature. Details of this modulation and its relations with other properties are, however, not yet clarified. C1 Tohoku Univ, Dept Phys, Aoba Ku, Sendai, Miyagi 9808578, Japan. Electrotech Lab, Div Phys Sci, Tsukuba, Ibaraki 3058568, Japan. Kyoto Univ, Chem Res Inst, Uji, Kyoto 6100011, Japan. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Japan Sci & Technol Corp, CREST, Tsukuba, Ibaraki 3050047, Japan. RP Kimura, H (reprint author), Tohoku Univ, Sci Measurements Res Inst, Aoba Ku, Sendai, Miyagi 9808577, Japan. RI Hirota, Kazuma/C-6797-2008; Yamada, Kazuyoshi/C-2728-2009 NR 32 TC 20 Z9 20 U1 0 U2 3 PU PHYSICAL SOC JAPAN PI TOKYO PA YUSHIMA URBAN BUILDING 5F, 2-31-22 YUSHIMA, BUNKYO-KU, TOKYO, 113-0034, JAPAN SN 0031-9015 J9 J PHYS SOC JPN JI J. Phys. Soc. Jpn. PD MAR PY 2000 VL 69 IS 3 BP 851 EP 857 DI 10.1143/JPSJ.69.851 PG 7 WC Physics, Multidisciplinary SC Physics GA 299MF UT WOS:000086201800034 ER PT J AU Haynes, JA AF Haynes, JA TI Materials challenges in developing advanced thermal barrier coatings SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Editorial Material C1 Oak Ridge Natl Lab, Ceram Surface Syst Grp, Oak Ridge, TN 37831 USA. RP Haynes, JA (reprint author), Oak Ridge Natl Lab, Ceram Surface Syst Grp, Oak Ridge, TN 37831 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD MAR PY 2000 VL 9 IS 1 BP 3 EP 5 PG 3 WC Materials Science, Coatings & Films SC Materials Science GA 306FZ UT WOS:000086587800001 ER PT J AU Haynes, JA Ferber, MK Porter, WD AF Haynes, JA Ferber, MK Porter, WD TI Thermal cycling behavior of plasmsa-sprayed thermal barrier coatings with various MCrAlX bond coats SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Article DE TBCs; thermal barrier coatings; cyclic oxidation; plasma spray; bond coat ID GAS-TURBINE ENGINES; FAILURE MECHANISMS; ALLOYS AB The influence of bond coat composition on the spallation resistance of plasma-sprayed thermal barrier coatings (TBCs) on single-crystal Rene N5 substrates was assessed by furnace thermal cycle testing of TBCs with various vacuum plasma spray (VPS) or air plasma-sprag (APS) MCrAlX (M = Ni and/or Co; and X = Y, Hf, and/or Si) bond coats. The TBC specimens with VPS bond coats were fabricated using identical parameters, with the exception of bond coat composition. The TBC lifetimes mere compared with respect to MCrAlX composition (before and after oxidation testing) and MCrAlX properties (surface roughness, thermal expansion, hardness, and Young's modulus). The average TBC spallation lifetimes varied significantly (from 174 to 344 1 h cycles at 1150 degrees C) as a function of bond coat composition. Results suggested a relationship between TBC durability and bond coat thermal expansion behavior below 900 degrees C. Although there mere only slight differences in their relative rates of cyclic oxidation weight gain, VPS MCrAlX bond coats with better oxide scale adhesion provided superior TBC lifetimes. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Haynes, JA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 20 TC 61 Z9 62 U1 1 U2 16 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD MAR PY 2000 VL 9 IS 1 BP 38 EP 48 DI 10.1361/105996300770350041 PG 11 WC Materials Science, Coatings & Films SC Materials Science GA 306FZ UT WOS:000086587800012 ER PT J AU Lance, MJ Haynes, JA Ferber, MK Cannon, WR AF Lance, MJ Haynes, JA Ferber, MK Cannon, WR TI Monoclinic zirconia distributions in plasma-sprayed thermal barrier coatings SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Article DE Raman microscopy; TBC; HOSP; plasma spraying; zirconia ID X-RAY-DIFFRACTION; RAMAN-SPECTROSCOPY; STABILIZED ZIRCONIA; YTTRIA; CERAMICS AB Phase composition in an air plasma-sprayed Y2O3-stabilized ZrO2 (YSZ) top coating of a thermal barrier coating (TBC) system was characterized. Both the bulk phase content and localized pockets of monoclinic zirconia were measured with Raman spectroscopy, The starting powder consisted of similar to 15 vol.% monoclinic zirconia, which decreased to similar to 2 vol.% in the as-sprayed coating. Monoclinic zirconia was concentrated in porous pockets that were evenly distributed throughout the TBC. The pockets resulted from the presence of unmelted granules in the starting powder. The potential effect of the distributed monoclinic pockets on TBC performance is discussed. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Rutgers State Univ, Dept Ceram & Mat Engn, Piscataway, NJ 08854 USA. RP Lance, MJ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Lance, Michael/I-8417-2016 OI Lance, Michael/0000-0001-5167-5452 NR 14 TC 10 Z9 10 U1 0 U2 5 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD MAR PY 2000 VL 9 IS 1 BP 68 EP 72 DI 10.1361/105996300770350078 PG 5 WC Materials Science, Coatings & Films SC Materials Science GA 306FZ UT WOS:000086587800015 ER PT J AU Bajt, S AF Bajt, S TI Molybdenum-ruthenium/beryllium multilayer coatings SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID EXTREME-ULTRAVIOLET AB A newly developed beryllium-based multilayer system consisting of polycrystalline Be and amorphous MoRu layers is presented. The multilayer exhibits many remarkable properties: reflectivity as high as 69.3% at a wavelength of 11.4 nm (achieved with 50 bilayers giving a bandwidth of 0.35 nm), near-zero intrinsic stress, and excellent smoothing properties. As compared with Mo/Si multilayers at 13.4 nm, the shorter wavelength of 11.4 nm is better matched to the spectral output of gas-jet laser produced plasma sources, allowing a much higher optical throughput of the extreme ultraviolet lithography (EUVL) tool. The properties of MoRu/Be are compared to other beryllium-based multilayers, which have been considered for reflective coatings for EUVL optics. (C) 2000 American Vacuum Society. [S0734-2101(00)08402-5]. C1 Univ Calif Lawrence Livermore Natl Lab, Informat Sci & Technol Program, Livermore, CA 94550 USA. RP Bajt, S (reprint author), Univ Calif Lawrence Livermore Natl Lab, Informat Sci & Technol Program, Livermore, CA 94550 USA. RI Bajt, Sasa/G-2228-2010 NR 14 TC 17 Z9 17 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAR-APR PY 2000 VL 18 IS 2 BP 557 EP 559 DI 10.1116/1.582224 PG 3 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 293BG UT WOS:000085831200045 ER PT J AU Gokhale, MB Stone, JM Gomersall, E AF Gokhale, MB Stone, JM Gomersall, E TI Co-synthesis to a hybrid RISC/FPGA architecture SO JOURNAL OF VLSI SIGNAL PROCESSING SYSTEMS FOR SIGNAL IMAGE AND VIDEO TECHNOLOGY LA English DT Article AB Hybrid architectures combining conventional processors with configurable logic resources enable efficient coordination of control with datapath computation. With integration of the two components on a single device, housekeeping tasks and, optionally, loop control and data-dependent branching, can be handled by the conventional processor, while regular datapath computation occurs on the configurable hardware. This paper describes a novel approach to programming such hybrid devices that gives the programmer control over mapping of data and computation between conventional processor and configurable logic. With a simple set of pragma and intrinsic function directives, the NAPA C language provides for manual control over perhaps the most important aspect of programming such hybrid devices. Alternatively, as experience is gained about tradeoffs between the two computational resources, mapping directives may eventually be generated by an external tool. The paper further describes a research prototype compiler that targets the hybrid processor model, with a concrete implementation for the National Semiconductor NAPA1000 chip. The NAPA C compiler parses the mapping directives, performs semantic analysis, and co-synthesizes a conventional processor executable combined with a configuration bit stream for the configurable logic. Two major compiler phases, the synthesis of pipelined loops and the datapath synthesis, are described in detail. C1 Sarnoff Corp, Princeton, NJ USA. Natl Semicond Corp, Santa Clara, CA USA. RP Gokhale, MB (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87544 USA. EM maya@sarnoff.com; edson@nsc.com NR 14 TC 13 Z9 13 U1 0 U2 2 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0922-5773 J9 J VLSI SIG PROC SYST JI J. VLSI Signal Process. Syst. Signal Image Video Technol. PD MAR PY 2000 VL 24 IS 2-3 BP 165 EP 180 DI 10.1023/A:1008141305507 PG 16 WC Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 293KC UT WOS:000085849900004 ER PT J AU Johnson, VM Rogers, LL AF Johnson, VM Rogers, LL TI Accuracy of neural network approximators in simulation-optimization SO JOURNAL OF WATER RESOURCES PLANNING AND MANAGEMENT-ASCE LA English DT Article ID GROUNDWATER-MANAGEMENT; GENETIC ALGORITHM; SAMPLING DESIGN; REMEDIATION AB Heuristic search techniques are highly flexible but computationally intensive optimization methods that require hundreds, sometimes thousands, of evaluations of the objective function to reach termination criteria in common water resources optimization applications. One way to make these techniques more tractable when the objective function depends on a time-consuming flow and transport model is to employ an empirical approximation of the model. The current study examines the impact of employing artificial neural networks (ANNs) and linear approximators (LAs) on the quality and quantity of solutions obtained from simulated annealing-driven searches on two different ground-water remediation problems. The quality of results obtained when ANNs served as substitutes for the full model was consistently comparable to that of results obtained when the full model itself was called in the course of the search. The effect on quality of results of substituting an LA for the full model was more variable. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Johnson, VM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 27 TC 70 Z9 72 U1 1 U2 14 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 USA SN 0733-9496 J9 J WATER RES PL-ASCE JI J. Water Resour. Plan. Manage.-ASCE PD MAR-APR PY 2000 VL 126 IS 2 BP 48 EP 56 DI 10.1061/(ASCE)0733-9496(2000)126:2(48) PG 9 WC Engineering, Civil; Water Resources SC Engineering; Water Resources GA 285FT UT WOS:000085379600002 ER PT J AU Boehly, TR Babushkin, A Bradley, DK Craxton, RS Delettrez, JA Epstein, R Kessler, TJ Knauer, JP McCrory, RL McKenty, PW Meyerhofer, DD Regan, S Seka, W Skupsky, S Smalyuk, VA Town, RPJ Yaakobi, B AF Boehly, TR Babushkin, A Bradley, DK Craxton, RS Delettrez, JA Epstein, R Kessler, TJ Knauer, JP McCrory, RL McKenty, PW Meyerhofer, DD Regan, S Seka, W Skupsky, S Smalyuk, VA Town, RPJ Yaakobi, B TI Laser uniformity and hydrodynamic stability experiments at the OMEGA laser facility SO LASER AND PARTICLE BEAMS LA English DT Article ID INERTIAL-CONFINEMENT-FUSION; RAYLEIGH-TAYLOR GROWTH; 3RD-HARMONIC GENERATION; BURNTHROUGH EXPERIMENTS; DRIVEN; SYSTEM; SUPPRESSION; SATURATION; TARGETS AB Experiments to demonstrate the effects of various beam-smoothing techniques have been performed on the 60-beam, 30-kJ UV OMEGA laser system. These include direct measurements of the effect beam-smoothing techniques have on laser beam nonuniformity and on both planar and spherical targets. Demonstrated techniques include polarization smoothing and "dual-tripler" third-harmonic generation required for future broad bandwidth (similar to1 THz) smoothing by spectral dispersion (SSD). The effects of improvements in single-beam uniformity are clearly seen in the target-physics experiment which also show the effect of the laser pulse shape on the efficacy of SSD smoothing. Saturation of the Rayleigh-Taylor (RT) growth of the broad-bandwidth features, in agreement with the Haan model (Haan, 1989),produced by laser imprinting has also been observed. C1 Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Boehly, TR (reprint author), Univ Rochester, Laser Energet Lab, 250 E River Rd, Rochester, NY 14623 USA. NR 31 TC 3 Z9 3 U1 2 U2 3 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0263-0346 J9 LASER PART BEAMS JI Laser Part. Beams PD MAR PY 2000 VL 18 IS 1 BP 11 EP 19 DI 10.1017/S0263034600181029 PG 9 WC Physics, Applied SC Physics GA 382QL UT WOS:000165833700002 ER PT J AU Axford, RA AF Axford, RA TI Solutions of the Noh problem for various equations of state using LIE groups SO LASER AND PARTICLE BEAMS LA English DT Article AB A method for developing invariant equations of state (EOS) for which solutions of the Noh problem will exist is developed. The ideal gas EOS is shown to be a special case of the general method. Explicit solutions of the Noh problem in planar, cylindrical, and spherical geometry are determined for a Mie-Gruneisen and the stiff gas equation of state. C1 Univ Calif Los Alamos Natl Lab, X HIM, Los Alamos, NM 87545 USA. RP Axford, RA (reprint author), Univ Illinois, Dept Nucl Engn, 103 S Goodwin Ave, Urbana, IL 61801 USA. NR 2 TC 4 Z9 4 U1 1 U2 4 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0263-0346 J9 LASER PART BEAMS JI Laser Part. Beams PD MAR PY 2000 VL 18 IS 1 BP 93 EP 100 DI 10.1017/S026303460018111X PG 8 WC Physics, Applied SC Physics GA 382QL UT WOS:000165833700011 ER PT J AU Burton, H AF Burton, H TI Minds, machines, and the multiverse: The quest for the quantum computer. SO LIBRARY JOURNAL LA English DT Book Review C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Burton, H (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD MAR 1 PY 2000 VL 125 IS 4 BP 116 EP 116 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 291CY UT WOS:000085717600175 ER PT J AU Trollsas, M Claesson, H Atthoff, B Hedrick, JL Pople, JA Gast, AP AF Trollsas, M Claesson, H Atthoff, B Hedrick, JL Pople, JA Gast, AP TI Conformational and structural properties of high functionality dendrimer-like star polymers synthesized from living polymerization techniques SO MACROMOLECULAR SYMPOSIA LA English DT Article; Proceedings Paper CT International Symposium on Recent Advances in Ring Opening (Metathesis) Pollmerization (RO(M)P 99) CY APR 12-15, 1999 CL MONS, BELGIUM SP Univ Mons Hainaut, Lab Polymer & Composite Mat, European Polymer Federat ID ANGLE NEUTRON-SCATTERING; ALIPHATIC POLYESTERS; BLOCK-COPOLYMERS; MOLECULAR-DYNAMICS; RATIONAL DESIGN; BUILDING-BLOCKS; END-GROUPS; MACROMOLECULES; ARCHITECTURES; INITIATION AB The design, synthesis and solution properties of dendritic-linear hybrid macromolecules is described. The synthetic strategy employs living ring-opening polymerization in combination with selective and quantitative organic transformations for the preparation of new molecular architectures similar to classical star polymers and dendrimers. The polymers were constructed from high molecular weight poly(epsilon-capiolactone) initiated from the surface hydroxyl groups of dendrimers derived from bis(hydroxymethyl) propionic acid (bis-MPA) in the presence of stannous 2-ethyl hexanoate (Sn(Oct)a). In this way, star and hyperstar poly(epsilon-caprolactones) were elaborated depending on the generation of dendrimer employed. The ROP from these hydroxy groups was found to be a facile process leading to controlled molecular weight, low dispersity products (Mw/M-n) < 1.15). In addition to the use of dendrimers as building blocks to star polymers, functional dendrons derived from bis-MPA were attached to chain ends of the star polymers, yielding structures that closely resemble that of the most advanced dendrimers. Measurements of the solution properties (hydrodynamic volume vs, molecular weight) on the dendritic-linear hybrids show a deviation from linearity, with a lower than expected hydrodynamic volume, analogous to the solution properties of dendrimers of high generation number. The onset of the deviation begins with the polymers initiated from the second generation dendrimer of bis-MPA and becomes more exaggerated with the higher generations. It was found that polymerization amplifies the nonlinear solution behavior of dendrimers. Small angle neutron scattering (SANS) measurements revealed that the radius of gyration scaled with arm functionality (f) as f(2/3), in accordance with the Daoud-Cotton model for many arm star polymer. C1 IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Stanford Univ, Dept Chem Engn, Stanford, CA 94305 USA. RP Hedrick, JL (reprint author), IBM Corp, Almaden Res Ctr, 650 Harry Rd, San Jose, CA 95120 USA. NR 59 TC 17 Z9 17 U1 0 U2 4 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1022-1360 J9 MACROMOL SYMP JI Macromol. Symp. PD MAR PY 2000 VL 153 BP 87 EP 108 DI 10.1002/1521-3900(200003)153:1<87::AID-MASY87>3.0.CO;2-B PG 22 WC Polymer Science SC Polymer Science GA 326EU UT WOS:000087720400009 ER PT J AU Chu, WJ Kuzniecky, RI Hugg, JW Abou-Khalil, B Gilliam, F Faught, E Hetherington, HP AF Chu, WJ Kuzniecky, RI Hugg, JW Abou-Khalil, B Gilliam, F Faught, E Hetherington, HP TI Statistically driven identification of focal metabolic abnormalities in temporal lobe epilepsy with corrections for tissue heterogeneity using H-1 spectroscopic imaging SO MAGNETIC RESONANCE IN MEDICINE LA English DT Article DE spectroscopic imaging; epilepsy; segmentation; N-acetyl-aspartate; creatine ID MAGNETIC-RESONANCE SPECTROSCOPY; HUMAN BRAIN; 4.1 T; LATERALIZATION; SEGMENTATION; MATTER; WATER; GRAY AB H-1 spectroscopic imaging of N-acetyl-aspartate, creatine, and choline has proven to be a sensitive indicator for the lateralization of seizure foci in temporal lobe epilepsy. Previous studies have used right-left comparisons to identify the epileptogenic tissue assuming that alterations due to the disease process outweigh the effects of tissue heterogeneity. To evaluate the effectiveness of tissue heterogeneity corrected analyses, we evaluated three criteria for lateralization of the seizure focus: 1) a statistically driven method adjusted for tissue composition, 2) a single valued threshold, and 3) a single global index of the hippocampus. The statistically driven analysis lateralized all eight patients correctly, whereas the single threshold method incorrectly lateralized one case and the global index failed to identify a significant difference in two cases. These findings indicate that increased accuracy and sensitivity can be obtained by correcting for tissue heterogeneity when analyzing spectroscopy studies of temporal lobe epilepsy. (C) 2000 Wiley-Liss, Inc. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Univ Alabama, Ctr Nucl Imaging Res, Birmingham, AL USA. Univ Alabama, UAB Epilepsy Ctr, Birmingham, AL USA. Univ Alabama, Dept Med, Birmingham, AL 35294 USA. Univ Alabama, Dept Neurol, Birmingham, AL 35294 USA. Vanderbilt Univ, Dept Neurol, Nashville, TN USA. RP Hetherington, HP (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. FU NCRR NIH HHS [RR11811]; NINDS NIH HHS [NS33991, NS33919] NR 41 TC 22 Z9 22 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0740-3194 J9 MAGNET RESON MED JI Magn. Reson. Med. PD MAR PY 2000 VL 43 IS 3 BP 359 EP 367 DI 10.1002/(SICI)1522-2594(200003)43:3<359::AID-MRM7>3.0.CO;2-C PG 9 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 288JF UT WOS:000085559100007 PM 10725878 ER PT J AU Yoshizaki, G Jin, W Patino, R Thomas, P Janecek, L AF Yoshizaki, G Jin, W Patino, R Thomas, P Janecek, L TI Structural organization of the Atlantic croaker connexin 32.2 gene and its 5 ' flanking region SO MARINE BIOTECHNOLOGY LA English DT Article DE AP-1; CRE; exon; intron; response elements; teleost ID OOCYTE MATURATIONAL COMPETENCE; GLUCOCORTICOID-RESPONSE ELEMENTS; GAP JUNCTION GENES; FUNCTIONAL-ANALYSIS; MOLECULAR-CLONING; ESTROGEN-RECEPTOR; MESSENGER-RNA; RAINBOW-TROUT; ER GENE; PROMOTER AB Gonadotropic hormone stimulates the accumulation of connexin (Cx) 32.2 messenger RNA in ovaries of the marine teleost Atlantic croaker. This effect can be mimicked by protein kinase A (PKA) activators and blocked by PKA inhibitors as well as protein kinase C (PKC) stimulators. However, the mechanisms of Cx32.2 gene regulation are unknown. In this study, we determined the structure of the Cx32.2 gene as a first step toward characterizing the regulatory mechanisms of Cx32.2 gene expression. A cosmid library of croaker genomic DNA was screened with a Cx32.2 complementary DNA probe. One positive clone was subcloned and sequenced. The Cx32.2 gene contained two exons and one intron. The first exon contained a portion of the 5' untranslated region (UTR), and the second exon contained the remaining 5' UTR, the amino acid coding region, and the 3' UTR. The distal 5' nanking region also contained a sequence homologous to a different croaker Cx gene, Cx32.7, but it is unclear if this sequence constitutes a pseudogene or an exon of the Cx32.7 gene. The 5' flanking region of the Cx32.2 gene contained two core cyclic AMP response elements (CRE, CGTCA) and one full-consensus activating protein- (AP)-1 binding site (AGTCAG). The distal core CRE was associated with a sequence that enhances CRE activity (GAGC). A third core CRE site was present in the intron. These Findings are consistent with the following hypotheses: the induction of ovarian Cx32.2 mRNA levels by gonadotropic hormone is at least partly mediated by CRE-dependent activation of the Cx32.2 gene, and the inhibition of basal and gonadotropic-hormone-stimulated ovarian Cx32.2 mRNA by PKC is due to negative effects on transcription via the AP-1 transcription factor complex. This study is the first to characterize the structure and putative response elements of the 5' flanking region of fish Cx genes. C1 Texas Tech Univ, Texas Cooperat Fish & Wildlife Res Unit, Lubbock, TX 79409 USA. Tokyo Univ Fisheries, Dept Aquat Biosci, Minato Ku, Tokyo 1088477, Japan. Univ Texas, MD Anderson Canc Ctr, Dept Med Specialties, Sect Endocrine Neoplasia & Hormonal Disorders, Houston, TX 77030 USA. Univ Texas, Inst Marine Sci, Port Aransas, TX 78373 USA. Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Patino, R (reprint author), Texas Tech Univ, Texas Cooperat Fish & Wildlife Res Unit, Lubbock, TX 79409 USA. RI YOSHIZAKI, Goro/O-1937-2014 NR 45 TC 4 Z9 5 U1 0 U2 3 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1436-2228 J9 MAR BIOTECHNOL JI Mar. Biotechnol. PD MAR-APR PY 2000 VL 2 IS 2 BP 154 EP 160 PG 7 WC Biotechnology & Applied Microbiology; Marine & Freshwater Biology SC Biotechnology & Applied Microbiology; Marine & Freshwater Biology GA 311VA UT WOS:000086905400005 ER PT J AU Greenwood, MS Minachi, A Thompson, RB AF Greenwood, MS Minachi, A Thompson, RB TI Effects of surface conditions on an ultrasonic inservice inspection SO MATERIALS EVALUATION LA English DT Article DE ultrasonic inservice inspection; surface roughness; step discontinuity on surface; weld crowns; computer modeling; inservice inspection recommendations; methods for NDT reliability; nondestructive testing; nuclear industry; piping; quality control; ultrasonic testing; weld inspection AB The primary objective of this research was to develop recommendations to limit the adverse effects of a rough surface and thereby increase the reliability of ultrasonic inse,ice inspections. To achieve this objective, engineering studies were conducted to validate experimentally a computer code that had been developed to model a pulse echo measurement. After the computer model had been validated, it was used as an engineering tool to study the effect of surface conditions and then used as a basis to develop recommendations relating to inservice inspections. The paper presents a brief description of the computer model, the results of extensive validation experiments, a description of an inservice inspection over a step discontinuity on the surface of a plate, use of the computer code to predict results of such an inspection for a 45 degree shear wave inspection, conclusions from the computer modeling studies, and the recommendations to limit adverse effects of a rough surface. C1 Pacific NW Lab, Richland, WA 99352 USA. SW Res Inst, San Antonio, TX 78228 USA. Iowa State Univ, Ctr Nondestruct Evaluat, Ames, IA 50011 USA. RP Greenwood, MS (reprint author), Pacific NW Lab, POB 999,MS K5-26, Richland, WA 99352 USA. NR 5 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC NON-DESTRUCTIVE TEST PI COLUMBUS PA 1711 ARLINGATE LANE PO BOX 28518, COLUMBUS, OH 43228-0518 USA SN 0025-5327 J9 MATER EVAL JI Mater. Eval. PD MAR PY 2000 VL 58 IS 3 BP 439 EP 448 PG 10 WC Materials Science, Characterization & Testing SC Materials Science GA 291DN UT WOS:000085719000011 ER PT J AU Kim, JC Schilling, CH Tomasik, P Auh, KH AF Kim, JC Schilling, CH Tomasik, P Auh, KH TI Effect of ultrasonication on the rheological behavior of alumina slurries with maltodextrin SO MATERIALS LETTERS LA English DT Article DE ultrasonication; rheology; alumina; slurry; maltodextrin; experimental; design ID SUSPENSIONS AB The rheology of alumina slurries with maltodextrin was studied with different shear rates using experimental design and statistical analysis. Different levels of ultrasonication were applied to the slurries before or after adding maltodextrin. Viscosities of the slurries were measured after equilibrating samples in a shaker for different shaking times, The: viscosities of alumina slurries decreased with the addition of maltodextrin and increased with ultrasonication intensity. There were minor differences in the viscosities of the slurries depending on whether maltodextrin was added before or after ultrasonication. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Hanyang Univ, Ceram Mat Res Inst, Seongdong Gu, Seoul 133791, South Korea. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Univ Agr, Dept Chem & Phys, Krakow, Poland. RP Kim, JC (reprint author), Hanyang Univ, Ceram Mat Res Inst, Seongdong Gu, 17 HanengdangDong, Seoul 133791, South Korea. EM kimjongcheol@netscape.net NR 15 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-577X J9 MATER LETT JI Mater. Lett. PD MAR PY 2000 VL 42 IS 6 BP 390 EP 393 DI 10.1016/S0167-577X(99)00217-7 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 291DC UT WOS:000085718000010 ER PT J AU Mitchell, BJ Richardson, JW Murphy, CD Ma, B Balachandran, U Hodges, JP Jorgensen, JD AF Mitchell, BJ Richardson, JW Murphy, CD Ma, B Balachandran, U Hodges, JP Jorgensen, JD TI Study of the mixed conducting SrFeCo0.5Oy ceramic membrane material by in-situ neutron powder diffraction SO MATERIALS RESEARCH BULLETIN LA English DT Article DE oxides; ceramics; neutron scattering; phase transactions ID OXYGEN PERMEATION; SURFACE EXCHANGE; METHANE; SYNGAS AB Dense ceramic tubes of the multi-phase mixed ionic/electronic conductor SrFeCo0.5Oy have been synthesized by solid-state reaction, and the stability of its component phases studied using in-situ neutron diffraction over the oxygen partial pressure (pO(2)) range 10(-0.68) to 10(-15.0) atm at 900 degrees C, This being the likely conditions to which membranes are exposed in operational methane conversion reactors. This material is stable between air and log pO(2) = -2.3, with Sr-2(Fe,Co)(3)O-y (236) being the majority phase. When the oxygen partial pressure is lowered, 236 starts decomposing into perovskite and rocksalt phases. The small fraction of remaining 236 rapidly undergoes decomposition at log pO(2) = -12.2, leaving only SrFeO2.5 and CoO. Rietveld analysis indicates that the oxygen content of the perovskite phase does not drop below O = 2.5 when log pO(2) = -15.0, while there is an indication that CoO is reduced to cobalt metal. This decomposition at low partial pressures may be reversed when the gas is switched back to air, i.e., SrFeO2.5 + CoO re-form Sr-2(Fe,Co)(3)O-y, to an extent that is seemingly dependent on sample and thermal history. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Richardson, JW (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Hodges, Jason/K-1421-2013; Ma, Beihai/I-1674-2013; OI Ma, Beihai/0000-0003-3557-2773; Hodges, Jason/0000-0003-3016-4578 NR 16 TC 18 Z9 18 U1 0 U2 2 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 MAR 1 PY 2000 VL 35 IS 4 BP 491 EP 501 DI 10.1016/S0025-5408(00)00242-7 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA 340YU UT WOS:000088564900001 ER PT J AU Meldrum, A Boatner, LA White, CW Ewing, RC AF Meldrum, A Boatner, LA White, CW Ewing, RC TI Ion irradiation effects in nonmetals: formation of nanocrystals and novel microstructures SO MATERIALS RESEARCH INNOVATIONS LA English DT Article DE zircon; pretulite; nanocrystals; irradiation; semiconductors; microstructure; nonmetals; ZnS; CdS ID SEMICONDUCTOR NANOCRYSTALS; OPTICAL-PROPERTIES; GAAS NANOCRYSTALS; BEAM SYNTHESIS; FUSED-SILICA; PROTON IMPLANTATION; CDSE NANOCRYSTALS; ZIRCON; GLASS; PARTICLES AB Ion implantation is a versatile and powerful technique for producing nanocrystal precipitates embedded in the near-surface region of materials. Radiation effects that occur during the implantation process can lead to complex microstructures and particle size distributions, and in the present work, we focus on the application of these effects to produce novel microstructural properties for insulating or semiconducting nanocrystals formed in optical host materials. Nanocrystal precipitates can be produced in two ways: by irradiation of pure (i.e., non-implanted) crystalline or amorphous materials, or by ion implantation followed by either thermal annealing or subsequent additional irradiation. Different methods for the formation of novel structural relationships between embedded nanocrystals and their hosts have been developed, and the results presented here demonstrate the general flexibility of ion implantation and irradiation techniques for producing unique near-surface nanocomposite microstructures in irradiated host materials. C1 Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Michigan, Dept NE & RS, Ann Arbor, MI 48109 USA. RP Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. EM dept@phys.ualberta.ca RI Boatner, Lynn/I-6428-2013 OI Boatner, Lynn/0000-0002-0235-7594 NR 89 TC 34 Z9 36 U1 0 U2 4 PU MANEY PUBLISHING PI LEEDS PA STE 1C, JOSEPHS WELL, HANOVER WALK, LEEDS LS3 1AB, W YORKS, ENGLAND SN 1432-8917 EI 1433-075X J9 MATER RES INNOV JI Mater. Res. Innov. PD MAR PY 2000 VL 3 IS 4 BP 190 EP 204 DI 10.1007/s100190050003 PG 15 WC Materials Science, Multidisciplinary SC Materials Science GA 294JT UT WOS:000085908700003 ER PT J AU Staudhammer, KP AF Staudhammer, KP TI A new brick micro production system which gives process cost savings and pollution reduction - and its application to the Ciudad Juarez El Paso micro brick industry SO MATERIALS TECHNOLOGY LA English DT Article C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Environm Waste Management LEG, Los Alamos, NM 87545 USA. RP Staudhammer, KP (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, POB 1663, Los Alamos, NM 87545 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MATRICE TECHNOLOGY LIMITED PI POULTON PA PO BOX 41, POULTON FY6 8GD, ENGLAND SN 1066-7857 J9 MATER TECHNOL JI Mater. Technol. PD MAR PY 2000 VL 15 IS 1 BP 25 EP 33 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA 325ZU UT WOS:000087707900006 ER PT J AU Battal, T Inal, OT Kurz, KL Causey, RA AF Battal, T Inal, OT Kurz, KL Causey, RA TI Metal coatings - Effects of deuterium irradiation on copper deposited aluminum 6061 substrates SO MATERIALS TECHNOLOGY LA English DT Review ID FILMS; ADHESION; PLASMA; TUNGSTEN AB There are several applications for metals where hydrogen isotope implantation may be a factor. One example is the inside of a fusion reactor. While most areas inside existing tokamaks are lined with graphite or carbon composites, certain areas are difficult to cover with these materials. To minimize hydrogen embrittlement and to minimize tritium inventory in fusion devices using this hydrogen isotope, the application of a copper coating to the metal may serve to lower the retention of the hydrogen. This effect is achieved by using a material like copper that has a high recombination rate coefficient for hydrogen. Another classic example of the use of copper coatings to minimize hydrogen uptake is the proposed Accelerator Production of Tritium (APT) device. In APT helium-3 is contained in aluminum tubes located in the intense neutron field generated by the proton spallation of neutrons from tungsten. The reaction of the neutrons with the helium-3 results in the production of energetic tritons. For the APT design, approximately 15% of all of the tritium produced will be implanted into the aluminum walls. The application of a copper coating to these aluminum tubes reduces the retention of tritium in the aluminum. This article considers a novel technique, based on plasma assisted physical vapor deposition, was utilized to deposit elemental pure copper on aluminum 6061 substrates at varying temperatures (150-200 degrees C). Copper coated substrates were then irradiated by a deuterium accelerator at 40+120 keV in a multienergetic cycle, which resulted in ion implantation with a total fluence of 3x10(17) ions/cm(2). Scanning Electron Microscopy, X-Ray Diffraction Analysis, Residual Stress Measurements, Secondary Ion Mass Spectroscopy Tensile Pull Testing and Scratch Adhesion Testing were performed to characterize the samples. Characterization of the irradiated samples revealed that coating pure copper onto the surface promoted the recombination of deuterium on the copper surface without its permeation into the substrate aluminum 6061. C1 New Mexico Tech, Dept Met & Mat Engn, Socorro, NM USA. Sandia Natl Labs, Adv Mat Res Dept, Livermore, CA 94550 USA. RP Inal, OT (reprint author), New Mexico Inst Min & Technol, Socorro, NM 87801 USA. NR 16 TC 0 Z9 0 U1 0 U2 1 PU MATRICE TECHNOLOGY LIMITED PI POULTON PA PO BOX 41, POULTON FY6 8GD, ENGLAND SN 1066-7857 J9 MATER TECHNOL JI Mater. Technol. PD MAR PY 2000 VL 15 IS 1 BP 61 EP 69 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA 325ZU UT WOS:000087707900011 ER PT J AU Atalay, M Laaksonen, DE Khanna, S Kaliste-Korhonen, E Hanninen, O Sen, CK AF Atalay, M Laaksonen, DE Khanna, S Kaliste-Korhonen, E Hanninen, O Sen, CK TI Vitamin E regulates changes in tissue antioxidants induced by fish oil and acute exercise SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Article DE glutathione; glutathione dependent enzymes; catalase; lipid peroxidation; protein oxidation ID MICROSOMAL LIPID-PEROXIDATION; HIGH-FAT DIETS; OXIDATIVE STRESS; SKELETAL-MUSCLE; CORN-OIL; GLUTATHIONE-PEROXIDASE; RAT-LIVER; HEART; PROTECTION; ACIDS AB Purpose: Prooxidant effects of fish oil supplementation could unfavorably affect the cardiovascular benefits of fish oil. We tested the effects of 8 wk vitamin E cosupplementation with fish oil on antioxidant defenses at rest and in response to exhaustive exercise in rats. Methods: Rats (N = 80) were divided into fish oil, fish oil and vitamin E (FOVE), soy oil, and soy oil and vitamin E (SOVE) supplemented groups. For the vitamin E supplemented rats, corresponding groups (FOVE-Ex and SOVE-Ex) performed an acute bout of exhaustive exercise after the supplementation period. Results: Fish oil supplementation increased the activity of catalase, glutathione peroxidase, and glutathione-S-transferase in the liver and red gastrocnemius (RG) muscle. Fish oil decreased liver total glutathione (TGSH) levels. Vitamin E supplementation decreased antioxidant enzyme activities to levels at or near those in SOVE in a tissue specific pattern. Vitamin E increased TGSH in liver, heart, and RG. Regression analysis showed TGSH to be a negative determinant of protein oxidative damage as measured by protein carbonyl levels in both liver and RG. Catalase activity was associated with liver lipid peroxidation as measured by thiobarbituric acid-reacting substances. The exercise-induced decrease in hepatic TGSH tended to be less in FOVE versus SOVE. Exhaustive exercise also modulated tissue antioxidant enzymes. Conclusions: Vitamin E supplementation markedly decreased fish oil induced antioxidant enzyme activities in all tissues. Sparing of glutathione may be an important mechanism by which vitamin E decreased tissue protein oxidative damage. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, EETD, Berkeley, CA 94720 USA. Univ Kuopio, Dept Physiol, FIN-70211 Kuopio, Finland. Univ Kuopio, Natl Lab Anim Ctr, FIN-70211 Kuopio, Finland. RP Sen, CK (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, EETD, 1 Cyclotron Rd,Bldg 90,Room 3031,Mail Stop 3200, Berkeley, CA 94720 USA. RI Sen, Chandan/A-8762-2013; Khanna, Savita/E-3378-2011 FU NIGMS NIH HHS [GM27345] NR 35 TC 26 Z9 26 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAR PY 2000 VL 32 IS 3 BP 601 EP 607 DI 10.1097/00005768-200003000-00008 PG 7 WC Sport Sciences SC Sport Sciences GA 294XD UT WOS:000085935000008 PM 10731001 ER PT J AU Molodkin, VB Nemoshkalenko, VV Nizkova, AI Olikhovskii, SI Pervak, KV Grankina, AI Ece, JE Larson, BK AF Molodkin, VB Nemoshkalenko, VV Nizkova, AI Olikhovskii, SI Pervak, KV Grankina, AI Ece, JE Larson, BK TI Combined methods of an integrated X-ray diffractometry for diagnostics of imperfect monocrystals SO METALLOFIZIKA I NOVEISHIE TEKHNOLOGII LA Russian DT Article ID OXYGEN PRECIPITATION; SILICON; GENERATION; CRYSTALS; DEFECTS AB The relatively simple analytical formulas derived previously by the authors for the total integrated reflection power (TIRP) of single crystals with randomly distributed defects in the limiting cases of the dynamical X-ray diffraction (the approximations of thin and thick crystals for symmetric Laue and asymmetric Bragg diffraction geometries) are applied to develop the new (combined) TIRP methods for the determination of defect parameters. The expressions for TIRP depend explicitly on the static Debye-Waller factor and two coefficients of the absorption due to the diffuse scattering for coherent and diffuse components of TIRP respectively, which include both defect and diffraction parameters. The cooperative treatment of thickness (at Laue geometry) and/or azimuth (at Bragg geometry) dependencies of TIRP measured for different wavelengths and/or reflections increases the sensitivity and reliability of TIRP methods for the determination of defect parameters. Potentialities of the combined methods are demonstrated theoretically and experimentally for the annealed silicon single crystal. C1 GV Kurdyumov Met Phys Inst, UA-03680 Kiev, Ukraine. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Molodkin, VB (reprint author), GV Kurdyumov Met Phys Inst, Bulv Akad Vernadskogo 36, UA-03680 Kiev, Ukraine. NR 28 TC 18 Z9 18 U1 0 U2 0 PU NATL ACAD SCIENCES UKRAINE, INST METAL PHYSICS PI KIEV 142 PA 36 ACADEMICIAN VERNADSKY BLVD, KIEV 142, UKRAINE UA-252180 SN 0204-3580 J9 METALLOFIZ NOV TEKH+ JI Metallofiz. Nov. Tekhnol.-Met. Phys. Adv. Techn. PD MAR PY 2000 VL 22 IS 3 BP 3 EP 16 PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 311FW UT WOS:000086874900001 ER PT J AU Minor, AM Morris, JW AF Minor, AM Morris, JW TI Growth of a Au-Ni-Sn intermetallic compound on the solder-substrate interface after aging SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article C1 Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. RP Minor, AM (reprint author), Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. NR 7 TC 72 Z9 73 U1 0 U2 9 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 MAR PY 2000 VL 31 IS 3 BP 798 EP 800 DI 10.1007/s11661-000-0022-5 PG 3 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 292UW UT WOS:000085814300022 ER PT J AU Gray, GT Meyers, MA Thadhani, NN Vecchio, KS AF Gray, GT Meyers, MA Thadhani, NN Vecchio, KS TI Symposium on Dynamic Behavior of Materials - (Part II) - Foreword SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Editorial Material C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif San Diego, San Diego, CA 92103 USA. Georgia Inst Technol, Atlanta, GA 30332 USA. RP Gray, GT (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RI Meyers, Marc/A-2970-2016 OI Meyers, Marc/0000-0003-1698-5396 NR 0 TC 0 Z9 0 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD MAR PY 2000 VL 31 IS 3A BP 809 EP 809 PG 1 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 297XC UT WOS:000086107100001 ER PT J AU Rivas, JM Zurek, AK Thissell, WR Tonks, DL Hixson, RS AF Rivas, JM Zurek, AK Thissell, WR Tonks, DL Hixson, RS TI Quantitative description of damage evolution in ductile fracture of tantalum SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Dynamic Behavior of Materials held at the 1998 Fall TMS/ASM Meeting CY OCT 11-15, 1998 CL ROSEMONT, ILLINOIS SP TMS, ASM Flow & Fracture Comm ID SPALLATION; GROWTH; NUCLEATION; ALLOYS; SOLIDS; MODEL AB Dynamic ductile fracture has been studied through incipient spallation experiments on two grades of tantalum. A commercially pure Ta material incipiently spalled at 252 m/s, a highly pure Ta material incipiently spalled at 246 m/s, and a highly pure Ta material preshocked at 250 m/s and incipiently spalled at 246 m/s were used. Microstructural parameters of the fracture process such as porosity, void-size distributions, and void aspect ratios have been quantified using image analysis and optical profilometry techniques. The commercially pure Ta,the highly pure Ta preshocked prior to spall, and the annealed high-purity Ta exhibited 27, 16.6, and 5.5 pet porosity, respectively. The void-size distribution observed in all three tests was adequately represented by either a log-normal or a linear combination of a log-normal and a Weibull distribution function. At least 80 pet of the aspect ratios observed in all three tests were adequately represented by a gamma distribution function. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Rivas, JM (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 36 TC 22 Z9 22 U1 2 U2 9 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 MAR PY 2000 VL 31 IS 3A BP 845 EP 851 DI 10.1007/s11661-000-0028-z PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 297XC UT WOS:000086107100006 ER PT J AU Rangaswamy, P Daymond, MR Bourke, MAM Von Dreele, R Bennett, K Jayaraman, N AF Rangaswamy, P Daymond, MR Bourke, MAM Von Dreele, R Bennett, K Jayaraman, N TI Texture and residual strain in two SiC/Ti-6-2-4-2 titanium composites SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Mechanisms and Mechanics of Composites Fracture held at the 1998 TMS Fall Meeting CY OCT 11-15, 1998 CL ROSEMONT, IL SP TMS, SMD, ASM, MSCTS ID RIETVELD REFINEMENT; MATRIX COMPOSITES; STRESSES; DIFFRACTION; MICROSTRUCTURE AB Residual strain and texture variations were measured in two titanium matrix composites reinforced with silicon carbide fibers (Ti/SiC) of similar composition but fabricated by different processing routes. Each composite comprised a Ti-6242 alpha/beta matrix alloy containing vol 35 pet continuous SiC fibers. In one, the matrix was produced by a plasma sprayed (PS) route, and in the other by a wire-drawn (WD) process. The PS and WD composites were reinforced with SCS-6 (SiC) and Trimarc (SiC) fibers, respectively. The texture in the titanium matrices differed significantly. The titanium matrix for the PS material exhibited random texture pre and post fabrication of the composite. For the WD material, the starting texture of the monolithic titanium matrix was approximate to 17 times random, but after consolidation into composite form, it was approximate to 6 times random. No significant differences were noted in the fiber-induced matrix residual strains between the composites prepared by the two procedures. However, the Trimarc (WD) fibers recorded higher (approximate to 1.3 times) compressive strains than the SCS-6 (PS) fibers. Stresses and stress balance results are reported. Plane-specific elastic moduli, measured in load tests on the unreinforced matrices, showed little difference. C1 Los Alamos Natl Lab, Lujan Ctr, Los Alamos, NM 87545 USA. Rutherford Appleton Lab, ISIS, Didcot OX11 0QX, Oxon, England. Univ Cincinnati, Dept Mat Sci & Engn, Cincinnati, OH 45221 USA. RP Rangaswamy, P (reprint author), Los Alamos Natl Lab, Lujan Ctr, POB 1663, Los Alamos, NM 87545 USA. OI Daymond, Mark/0000-0001-6242-7489 NR 42 TC 9 Z9 9 U1 0 U2 6 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 MAR PY 2000 VL 31 IS 3A BP 889 EP 898 DI 10.1007/s11661-000-0032-3 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 297XC UT WOS:000086107100011 ER PT J AU Zhao, W Liaw, PK Belardinelli, R Joy, DC Brooks, CR McHargue, CJ AF Zhao, W Liaw, PK Belardinelli, R Joy, DC Brooks, CR McHargue, CJ TI Damage mechanisms and fiber orientation effects on the load-bearing capabilities of a NEXTEL/BLACKGLAS low-cost ceramic composite SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Mechanisms and Mechanics of Composites Fracture held at the 1998 TMS Fall Meeting CY OCT 11-15, 1998 CL ROSEMONT, ILLINOIS SP TMS, SMD, ASM, MSCTS ID SCANNING ELECTRON-MICROSCOPY; MODULI AB In this article, the fiber orientation effect on the load-bearing capabilities of a NEXTEL/BLACKGLAS low-cost composite was experimentally investigated, and damage mechanisms were analyzed. Ultrasonic nondestructive evaluation (NDE) was performed to interrogate the composite samples before testing. A four-point bending test was conducted to study the mechanical behavior. Scanning electron microscopy (SEM) fractography and SEM energy-dispersive X-ray spectroscopy (EDXS) along with SEM/EDXS elemental mapping were employed to characterize damage mechanisms, microstructures, and the microchemical distribution of elements following mechanical tests. A mechanistic understanding of the fracture behavior of the NEXTEL/BLACKGLAS ceramic composite was provided. C1 Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. Northrop Grumman Mil Aircraft Syst Div, Dallas, TX 75265 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Oak Ridge, TN 37831 USA. RP Zhao, W (reprint author), Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. NR 29 TC 12 Z9 12 U1 0 U2 1 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 MAR PY 2000 VL 31 IS 3A BP 911 EP 920 DI 10.1007/s11661-000-0034-1 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 297XC UT WOS:000086107100013 ER PT J AU Hofer, P Miller, MK Babu, SS David, SA Cerjak, H AF Hofer, P Miller, MK Babu, SS David, SA Cerjak, H TI Atom probe field ion microscopy investigation of boron containing martensitic 9 Pct chromium steel SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID GRAIN-BOUNDARY SEGREGATION; AUSTENITIC STAINLESS-STEEL; BEHAVIOR AB The chemical compositions of the ferrite matrix and various other phases in an Fe-0.17 C-9 Cr-1.55 Mo-0.27 V-0.015 N-0.01B (mass pct) steel in as-received and crept conditions were measured with atom probe field ion microscopy (APFIM). The results showed the presence of some residual boron within the ferrite matrix. Analyses showed that boron was distributed within M23C6, M6C, MX, and Laves phases. Phosphor atoms were detected at the M23C6-ferrite interface in the crept condition. The results are compared to predictions from thermodynamic calculations. C1 Graz Tech Univ, Inst Mat Sci Welding & Forming, Graz, Austria. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hofer, P (reprint author), Andriz Co, A-8010 Graz, Austria. RI Babu, Sudarsanam/D-1694-2010 OI Babu, Sudarsanam/0000-0002-3531-2579 NR 21 TC 23 Z9 24 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 MAR PY 2000 VL 31 IS 3A BP 975 EP 984 DI 10.1007/s11661-000-0039-9 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 297XC UT WOS:000086107100018 ER PT J AU Jin, Z Cady, C Gray, GT Kim, YW AF Jin, Z Cady, C Gray, GT Kim, YW TI Mechanical behavior of a fine-grained duplex gamma-TiAl alloy SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID POLYSYNTHETICALLY TWINNED CRYSTALS; POSITIVE TEMPERATURE-DEPENDENCE; AT-PERCENT AL; TITANIUM ALUMINIDES; YIELD STRESS; DEFORMATION CHARACTERISTICS; DISLOCATION CONFIGURATIONS; INTERMETALLIC COMPOUND; PST CRYSTALS; SUPERPLASTIC BEHAVIOR AB The mechanical behavior of a fine-grained duplex gamma-TiAl alloy was studied in compression at strain rates ranging from 0.001 to 2000 s(-1) and temperatures from -196 degrees C to 1200 degrees C. The temperature dependence of the yield and flow stresses is found to depend on the strain rate. At strain rates of 0.001 and 0.1 s(-1), the yield stress decreases as the temperature increases, with a plateau between 600 degrees C and 800 degrees C. At strain rates of 35 and 2000 s-(1), the yield stress exhibits a positive temperature dependence at temperatures above 600 degrees C; however, postyield flow stresses exhibit a reduced temperature dependency. The work-hardening rate decreases dramatically with temperature at low and high temperatures, with a plateau occurring at intermediate temperatures for all strain rates. The work-hardening-rate plateau is seen to extend to higher temperatures as the strain rate increases. The strain-rate sensitivity at strain rates of 0.1 s(-1) and greater is lower than 0.1, although it increases slightly with temperature. At 0.001 s(-1), the strain-rate sensitivity increases dramatically at high temperatures (equal to 4.5 at 1200 degrees C), The anomalous (positive) temperature dependence of the yield stress at high strain rates (>1 s(-1)) and high temperatures (>600 degrees C) is explained via a dislocation-jog pinning mechanism. The negative temperature dependence of the yield stress at low strain rates (<1 s(-1)) and high temperatures (>900 degrees C) is thought to be due to a thermally activated dislocation-jog climb process in the grain interiors and/or deformation and recovery processes at/near grain boundaries. The decreased anomalous temperature dependence of the flow stress at high strain fates and high temperatures is ascribed to dynamic recovery promoted by adiabatic heating. C1 Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Universal Energy Syst Inc, Mat & Proc Div, Dayton, OH 45432 USA. RP Jin, Z (reprint author), Reynolds Met Co, Chester, VA 23836 USA. NR 63 TC 20 Z9 24 U1 3 U2 15 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1073-5623 EI 1543-1940 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD MAR PY 2000 VL 31 IS 3A BP 1007 EP 1016 DI 10.1007/s11661-000-0042-1 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 297XC UT WOS:000086107100021 ER PT J AU Dong, JH Lin, YS Hu, MZC Peascoe, RA Payzant, EA AF Dong, JH Lin, YS Hu, MZC Peascoe, RA Payzant, EA TI Template-removal-associated microstructural development of porous-ceramic-supported MFI zeolite membranes SO MICROPOROUS AND MESOPOROUS MATERIALS LA English DT Article DE calcination; crack formation; gas separation; MFI zeolite membrane; thermal behavior ID SILICALITE MEMBRANES; PERMEATION; SEPARATION; MIXTURES; FILMS; VIEW AB Defect-free thin MFI zeolite films were synthesized on porous alpha-alumina and yttria-doped zirconia (YZ) substrates by an in situ crystallization method using tetrapropylammonium hydroxide (TPAOH) as a template. The microstructure evolution of the supported zeolite films during calcination for template removal was studied by high-temperature X-ray diffraction and in situ gas permeance. Removal of the template from the zeolite films occurs at 350-500 degrees C and is accompanied by a substantial shrinkage in the zeolite framework. After the template is removed from the zeolite at high temperatures, the zeolite crystals expand on cooling while the support shrinks. A compressive stress develops in the zeolite film during the cooling process when the zeolite crystallites are bound to the support after template removal. Without annealing prior to template removal, this stress induces cracks in the YZ-supported MFI films. High-quality MFI membranes were obtained on both alpha-alumina and YZ supports by using a suitable calcination temperature program. Removal of the template can either create or enlarge intercrystalline gaps as the zeolite crystallites decrease in size and draw away from adjacent crystallites. These gaps constitute the microporous non-zeolitic pores affecting the permselectivity of single-gas permeation for H-2 and SF6. Both alumina- and YZ-supported MFI membranes show very good separation properties for hydrogen and n-butane mixtures, although the YZ-supported MFI films appear to have larger non-zeolitic pores than the alumina-supported membranes. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Cincinnati, Dept Chem Engn, Cincinnati, OH 45221 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Lin, YS (reprint author), Univ Cincinnati, Dept Chem Engn, Cincinnati, OH 45221 USA. RI Payzant, Edward/B-5449-2009; Lin, Jerry/F-1235-2010; OI Payzant, Edward/0000-0002-3447-2060; Lin, Jerry/0000-0001-5905-8336; Hu, Michael/0000-0001-8461-9684 NR 20 TC 166 Z9 172 U1 4 U2 53 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-1811 J9 MICROPOR MESOPOR MAT JI Microporous Mesoporous Mat. PD MAR PY 2000 VL 34 IS 3 BP 241 EP 253 DI 10.1016/S1387-1811(99)00175-4 PG 13 WC Chemistry, Applied; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 299VH UT WOS:000086218200001 ER PT J AU Thoma, SG Nenoff, TM AF Thoma, SG Nenoff, TM TI A novel synthesis of zeolite W using organometallic precursors SO MICROPOROUS AND MESOPOROUS MATERIALS LA English DT Article DE MER framework; merlinoite; organocation template; synthesis; zeolite W ID PURE-SILICA ZEOLITES; STRUCTURE DIRECTION; MERLINOITE; MECHANISM AB Zeolite W has been synthesized hydrothermally using organometallic silicon and aluminum precursors both with and without an organocation. The reaction using the organocation yielded a fully crystalline, relatively uniform crystal size product, with no organic molecules occluded in the pores. In contrast, the product obtained from an identical reaction, except for the absence of the organocation reactant, contained amorphous as well as crystalline material and the crystalline phase showed a large diversity in both crystal size and morphology. The use of organometallic precursors, either with or without an organocation, allows for the crystallization of the MER framework at much lower OH/SiO2 and (K+Na-Al)/Si ratios than is typical of inorganic systems. The reaction products were characterized by X-ray diffraction, scanning electron microscopy, electron dispersive spectroscopy, Fourier transform infrared, and thermal analyses. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Catalysis & Chem Technol Dept, Albuquerque, NM 87185 USA. RP Nenoff, TM (reprint author), Sandia Natl Labs, Catalysis & Chem Technol Dept, POB 5800,MS 0710, Albuquerque, NM 87185 USA. NR 9 TC 11 Z9 12 U1 2 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-1811 J9 MICROPOR MESOPOR MAT JI Microporous Mesoporous Mat. PD MAR PY 2000 VL 34 IS 3 BP 301 EP 306 DI 10.1016/S1387-1811(99)00182-1 PG 6 WC Chemistry, Applied; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 299VH UT WOS:000086218200006 ER PT J AU Zimmerman, JA Gao, HJ Abraham, FF AF Zimmerman, JA Gao, HJ Abraham, FF TI Generalized stacking fault energies for embedded atom FCC metals SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID CRACK-TIP; DISLOCATION NUCLEATION; ULTRASOFT PSEUDOPOTENTIALS; INSTABILITY DYNAMICS; COMPUTER-SIMULATION; MOLECULAR-DYNAMICS; FIRST-PRINCIPLES; FRACTURE; SILICON; BRITTLE AB Atomistic calculations for the [112]-generalized stacking fault (GSF) energy curve are performed for various embedded atom models of FCC metals. Models include those by Voter and Chen: Angelo, Moody and Baskes; Oh and Johnson; Mishin and Farkas; and Ercolessi and Adams. The resulting curves show similar characteristics but vary in their agreement with the experimental estimates of the intrinsic stacking fault energy, gamma(sf), and with density functional theory (DFT) calculations of the GSF curve. These curves are used to obtain estimates of the unstable stacking fault energy, gamma(us), a quantity used in a criterion for dislocation nucleation. Curves For nickel and copper models show the theoretically expected skewed sinusoidal shape; however, several of the aluminium models produce an irregularly shaped GSF curve. Copper and aluminium values for gamma(us) are underestimates of calculations from DFT, although some of the nickel models produce a value matching one of the available DFT results. Values for gamma(sf) are either fitted to, or underestimate, the measured results. For use in simulations, the authors recommend using the Voter and Chen potential for copper, and either the Angelo, Moody and Baskes potential or the Voter and Chen potential for nickel. None of the potentials model aluminium well, indicating the need for a more-advanced empirical potential. C1 Stanford Univ, Div Mech & Computat, Stanford, CA 94305 USA. IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. RP Zimmerman, JA (reprint author), Sandia Natl Labs, Mail Stop 9161,POB 969, Livermore, CA 94551 USA. RI Gao, Huajian/F-9360-2010; Zimmerman, Jonathan/A-8019-2012 NR 39 TC 175 Z9 178 U1 8 U2 62 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD MAR PY 2000 VL 8 IS 2 BP 103 EP 115 DI 10.1088/0965-0393/8/2/302 PG 13 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 301RX UT WOS:000086325000002 ER PT J AU Nedelcu, S Kizler, P Schmauder, S Moldovan, N AF Nedelcu, S Kizler, P Schmauder, S Moldovan, N TI Atomic scale modelling of edge dislocation movement in the alpha-Fe-Cu system SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID SIMULATIONS; CRYSTALS AB The aim of the present work is to investigate by molecular dynamics (MD) calculations the interaction between a moving edge dislocation in an alpha-Fe crystal and a copper precipitate. In the absence of external stresses, two edge dislocations with the same slip plane and opposite Burgers vectors within a perfect a-Fe crystal lattice are investigated. In agreement with Frank's rule, the movement of the dislocations under mutual attraction is found and attention is focused on the interaction between one of the dislocations and the Cu precipitate. The critical resolved,sear stress of the Fe was calculated and the influence of different sizes of Cu precipitates on the dislocation mobility was studied. The pinning of the dislocation line at the Cu inclusion as derived from the atomistic modelling agrees with previously published continuum theoretical behaviour of pinned dislocations. Therefore, nanosimulation as a way to model precipitation hardening could be established as a useful scientific tool. C1 Univ Stuttgart, Staatliche Mat Prufungsanstalt, D-70569 Stuttgart, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. RP Kizler, P (reprint author), Univ Stuttgart, Staatliche Mat Prufungsanstalt, Pfaffenwaldring 32, D-70569 Stuttgart, Germany. NR 23 TC 25 Z9 27 U1 0 U2 11 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD MAR PY 2000 VL 8 IS 2 BP 181 EP 191 DI 10.1088/0965-0393/8/2/308 PG 11 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 301RX UT WOS:000086325000008 ER PT J AU Lacks, SA Ayalew, S de la Campa, AG Greenberg, B AF Lacks, SA Ayalew, S de la Campa, AG Greenberg, B TI Regulation of competence for genetic transformation in Streptococcus pneumoniae: expression of dpnA, a late competence gene encoding a DNA methyltransferase of the DpnII restriction system SO MOLECULAR MICROBIOLOGY LA English DT Article ID DIPLOCOCCUS-PNEUMONIAE; ESCHERICHIA-COLI; PLASMID; CLONING; RESISTANCE; METHYLASE; PROTEINS; CASSETTE; OPERON AB The chromosomal DpnII gene cassette of Streptococcus pneumoniae encodes two methyltransferases and an endonuclease. One methyltransferase acts on double-stranded and the other on single-stranded DNA. Two mRNAs are transcribed from the cassette. One, a SigA promoter transcript, includes all three genes; the other includes a truncated form of the second methyltransferase gene (dpnA) and the endonuclease gene. The truncated dpnA, which is translated from the second start codon in the full gene, was shown to produce active enzyme. A promoter reporter plasmid for S. pneumoniae was devised to characterize the promoter for the second mRNA. This transcript was found to depend on a promoter that responded to the induction of competence for genetic transformation. The promoter contains the combox sequence recognized by a SigH-containing RNA polymerase. As part of the competence regulon, the dpnA gene makes a product able to methylate incoming plasmid strands to protect them from the endonuclease and allow plasmid establishment. Its function differs from most genes in the regulon, which are involved in DNA uptake. Comparison of R6 and Rx strains of S. pneumoniae showed the temperature dependence of transformation in R6 to result from temperature sensitivity of the uptake apparatus and not the development of competence. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Lacks, SA (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. EM lacks@bnl.gov FU NIAID NIH HHS [AI14885] NR 38 TC 32 Z9 33 U1 0 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0950-382X J9 MOL MICROBIOL JI Mol. Microbiol. PD MAR PY 2000 VL 35 IS 5 BP 1089 EP 1098 DI 10.1046/j.1365-2958.2000.01777.x PG 10 WC Biochemistry & Molecular Biology; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA 289MP UT WOS:000085625800011 PM 10712690 ER PT J AU Yang, F Forrer, P Dauter, Z Conway, JF Cheng, NQ Cerritelli, ME Steven, AC Pluckthun, A Wlodawer, A AF Yang, F Forrer, P Dauter, Z Conway, JF Cheng, NQ Cerritelli, ME Steven, AC Pluckthun, A Wlodawer, A TI Novel fold and capsid-binding properties of the lambda-phage display platform protein gpD SO NATURE STRUCTURAL BIOLOGY LA English DT Article ID HERPES-SIMPLEX VIRUS; BACTERIOPHAGE-LAMBDA; RECOMBINANT BACULOVIRUSES; MACROMOLECULAR STRUCTURES; SURFACE LATTICE; SYSTEM; VP26; DIFFRACTION; REPLACEMENT; MATURATION AB The crystal structure of gpD, the capsid-stabilizing protein of bacteriophage lambda, was solved at 1.1 Angstrom resolution. Data were obtained from twinned crystals in space group PZ, and refined with anisotropic temperature factors to an R-factor of 0.098 (R-free = 0.132). GpD (109 residues) has a novel fold with an unusually low content of regular secondary structure. Noncrystallographic trimers with substantial intersubunit interfaces were observed. The C-termini are well ordered and located on one side of the trimer, relatively far from its three-fold axis. The N-termini are disordered up to Ser 15, which is close to the three-fold axis and on the same side as the C-termini. A density map of the icosahedral viral capsid at 15 Angstrom resolution, obtained by cryo-electron microscopy and image reconstruction, reveals gpD trimers, seemingly indistinguishable from the ones seen in the crystals, at all threefold sites. The map further reveals that the side of the trimer that binds to the capsid is the side on which both termini reside. Despite this orientation of the gpD trimer, fusion proteins connected by linker peptides to either terminus bind to the capsid, allowing protein and peptide display. C1 Univ Zurich, Inst Biochem, CH-8057 Zurich, Switzerland. NCI, Macromol Crystallog Lab, Program Struct Biol, Frederick Canc Res & Dev Ctr, Frederick, MD 21702 USA. Brookhaven Natl Lab, NCI, FCRDC, Upton, NY 11973 USA. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. NIAMSD, Struct Biol Lab, Bethesda, MD 20892 USA. RP Pluckthun, A (reprint author), Univ Zurich, Inst Biochem, Winterthurerstr 190, CH-8057 Zurich, Switzerland. RI Pluckthun, Andreas/C-2746-2009; Conway, James/A-2296-2010 OI Pluckthun, Andreas/0000-0003-4191-5306; Conway, James/0000-0002-6581-4748 NR 54 TC 108 Z9 114 U1 1 U2 7 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 MAR PY 2000 VL 7 IS 3 BP 230 EP 237 PG 8 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 289YE UT WOS:000085648900020 PM 10700283 ER PT J AU Unal, C Bohl, WR Pasamehmetoglu, KO AF Unal, C Bohl, WR Pasamehmetoglu, KO TI Modeling of heat and mass transfer in accelerator targets during postulated accidents SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article AB The modeling of thermal-chemical behavior of targets used in accelerator applications is an important part of safety analysis. Tungsten is considered as a target material to produce tritium in a linear proton accelerator. The prediction of the chemical reactivity of tungsten in a steam flow at high temperatures is the most important part of a safety analysis of target design. The oxidation and volatilization of tungsten in steam at high temperatures is a complex phenomenon that involves various mechanisms (depending on the temperature), steam pressure, and steam velocity. A simple diffusion model that considers chemical equilibrium at the reaction interface and effective diffusion thickness, including the boundary and oxide layers, is proposed for predicting the volatilization rate. The proposed simple model predicts the available data reasonably well. The proposed model is implemented into a computer program that is developed to predict the radiological releases during postulated loss-of-coolant accidents (LOCAs). The computer program models heat production, heat transfer, and oxidation reactions in the multiple radiation enclosures representing the accelerator target elements. It treats each element of the radiation enclosures as a lumped control volume, or heat structure. Each heat structure may generate or lose heal by conduction, convection, or radiation and is subject to mass loss as a result of oxidation, melting, and volatilization. Postulated beyond-design-basis LOCAs are simulated with this computer program for the accelerator-production-of-tritium target. Sample calculations demonstrate oxidation/volatilization model capabilities and sensitivity to the assumptions selected. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Nucl Syst Design & Anal Grp, Los Alamos, NM 87545 USA. RP Unal, C (reprint author), Univ Calif Los Alamos Natl Lab, Nucl Syst Design & Anal Grp, POB 1663,TSA-10,MS K575, Los Alamos, NM 87545 USA. NR 20 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0029-5493 J9 NUCL ENG DES JI Nucl. Eng. Des. PD MAR PY 2000 VL 196 IS 2 BP 185 EP 200 DI 10.1016/S0029-5493(99)00297-6 PG 16 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 284ZP UT WOS:000085363000006 ER PT J AU Baker, C Glad, S AF Baker, C Glad, S TI Maintaining a steady arm SO NUCLEAR ENGINEERING INTERNATIONAL LA English DT Article C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Baker, C (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU REED BUSINESS INFORMATION LTD PI SUTTON PA QUADRANT HOUSE THE QUADRANT, SUTTON SM2 5AS, SURREY, ENGLAND SN 0029-5507 J9 NUCL ENG INT JI Nucl. Eng. Int. PD MAR PY 2000 VL 45 IS 548 BP 30 EP 31 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 295HZ UT WOS:000085961800006 ER PT J AU Oikawa, T Ushigusa, K Forest, CB Nemoto, M Naito, O Kusama, Y Kamada, Y Tobita, K Suzuki, S Fujita, T Shirai, H Fukuda, T Kuriyama, M Itoh, T Okumura, Y Watanabe, K Grisham, L AF Oikawa, T Ushigusa, K Forest, CB Nemoto, M Naito, O Kusama, Y Kamada, Y Tobita, K Suzuki, S Fujita, T Shirai, H Fukuda, T Kuriyama, M Itoh, T Okumura, Y Watanabe, K Grisham, L CA JT-60 Team TI Heating and non-inductive current drive by negative ion based NBI in JT-60U SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA ID H-MODE TRANSITION; PLASMAS; INJECTION; TOKAMAK AB The current drive and heating properties of negative ion based NBI have been studied comprehensively in JT-60U. It has been confirmed from shine-through measurements of the injected beam (350 keV) that multistep ionization processes are essential in the ionization processes of high energy particles. The profile of the current density driven by a negative ion based NE (N-NB) has been determined experimentally. This is in good agreement with the theoretical prediction, and N-NB driven current reached 0.6 MA with E-B = 360 eV and P-INJ = 3.7 MW. The current drive efficiency rico is increased by increasing electron temperature and improved by increasing beam energy. The fast ions from N-NBs are well confined in the enhanced confinement core by the weak poloidal magnetic field of reversed shear plasmas. A clear H mode transition was obtained with N-NB dominant heating, where the net absorbed power required for an H mode transition seemed similar to the previous result obtained in JT-60U using a low energy beam (90 keV). With the strong electron heating by N-NBI (80% absorbed by electrons), an H factor (= tau(E)/tau(E)(ITER-89PL)) of 1.64 with T-e(0) = 1.4T(i)(0) was obtained in the steady state ELMy phase. C1 Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki 31101, Japan. Univ Wisconsin, Madison, WI USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Oikawa, T (reprint author), Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki 31101, Japan. RI Kikuchi, Mitsuru/O-1036-2015; Suzuki, Shingo/I-6137-2016 OI Kikuchi, Mitsuru/0000-0002-5485-8737; Suzuki, Shingo/0000-0002-2023-0490 NR 15 TC 32 Z9 32 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 MAR PY 2000 VL 40 IS 3Y SI 3 BP 435 EP 443 DI 10.1088/0029-5515/40/3Y/301 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500002 ER PT J AU Phillips, CK Bell, MG Bell, RE Bernabei, S Bettenhausen, M Bush, CE Clark, D Darrow, DS Fredrickson, ED Hanson, GR Hosea, JC LeBlanc, BP Majeski, RP Medley, SS Nazikian, R Ono, M Park, HK Petrov, MP Rogers, JH Schilling, G Skinner, CH Smithe, DN Synakowski, EJ Taylor, G Wilson, JR AF Phillips, CK Bell, MG Bell, RE Bernabei, S Bettenhausen, M Bush, CE Clark, D Darrow, DS Fredrickson, ED Hanson, GR Hosea, JC LeBlanc, BP Majeski, RP Medley, SS Nazikian, R Ono, M Park, HK Petrov, MP Rogers, JH Schilling, G Skinner, CH Smithe, DN Synakowski, EJ Taylor, G Wilson, JR TI ICRF heating and profile control techniques in TFTR SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA ID EDGE TURBULENCE; PLASMAS AB In fast wave to ion Bernstein wave made conversion experiments in DT supershot plasmas, localized efficient ion heating rather than electron heating was observed, which was due to Doppler broadened tritium cyclotron resonance overlap into the mode conversion region. The ion temperature heat pulse associated with RF power modulation in this regime could provide a diagnostic tool for measuring the local ion thermal conductivity in various confinement regimes. In direct launch ion Bernstein wave heating experiments, core power coupling was limited by the excitation of parasitic edge modes. However, a sheared poloidal flow was observed that is consistent in both magnitude and direction with theoretical models based on RF driven Reynolds stress. With the modest power coupled to the core (similar to 360 kW), the magnitude of the shear in the observed flow was estimated to be a factor of 3-4 too low to trigger transport barrier formation through localized shear suppression of turbulence. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Mission Res Corp, Newington, VA USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. RP Phillips, CK (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 10 TC 22 Z9 22 U1 4 U2 11 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAR PY 2000 VL 40 IS 3Y SI 3 BP 461 EP 466 DI 10.1088/0029-5515/40/3Y/304 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500005 ER PT J AU Willi, O Barringer, L Bell, A Borghesi, M Davies, J Gaillard, R Iwase, A MacKinnon, A Malka, G Meyer, C Nuruzzaman, S Taylor, R Vickers, C Hoarty, D Gobby, P Johnson, R Watt, RG Blanchot, N Canaud, B Croso, H Meyer, B Miquel, JL Reverdin, C Pukhov, A Meyer-ter-Vehn, J AF Willi, O Barringer, L Bell, A Borghesi, M Davies, J Gaillard, R Iwase, A MacKinnon, A Malka, G Meyer, C Nuruzzaman, S Taylor, R Vickers, C Hoarty, D Gobby, P Johnson, R Watt, RG Blanchot, N Canaud, B Croso, H Meyer, B Miquel, JL Reverdin, C Pukhov, A Meyer-ter-Vehn, J TI Inertial confinement fusion and fast ignitor studies SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA ID LASER IMPRINT; FOAM BUFFER; RESOLUTION; TARGETS; PLASMA; PULSE AB Laser imprinting has been studied and, in particular, saturation of areal density perturbations induced by near single mode laser imprinting was observed. Several issues important for the foam buffered direct drive scheme have been investigated. These studies included measurements of the absolute levels of stimulated Brillouin and Raman scattering observed from laser irradiated low density foam targets, either bare or overcoated with a thin layer of gold. A novel scheme is proposed to increase the pressure in indirectly driven targets. By heating a foam supersonically that is attached to a solid target the pressure generated is not only the ablation pressure but also the combined pressure due to ablation at the foam-foil interface and the heated foam material. Planar brominated plastic foil targets overcoated with a low density foam were irradiated by a soft ?( ray pulse. The pressure was obtained by comparing the rear side trajectory of the driven target observed by soft X ray. radiography with one dimensional radiation hydrodynamic simulations. Observations were also carried out of the transition from supersonic to subsonic propagation of an ionization front in low density chlorinated foam targets irradiated by an intense soft X ray pulse. The diagnostic for these measurements was K shell point projection absorption spectroscopy. In the fast ignitor area the channelling and guiding of picosecond laser pulses through underdense plasmas, preformed density channels and microtubes were investigated. It was observed that a large fraction of the incident laser energy can be propagated. Megagauss magnetic fields were measured, with a polarimetric technique, during and after propagation of intense picosecond pulses in preionized plasmas. Two types of toroidal fields, of opposite orientation, were detected. In addition, the production and propagation of an electron beam through solid glass targets irradiated at intensities above 10(19) W/cm(2) were observed using optical probing techniques. C1 Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London, England. AWE Aldermaston, Reading, Berks, England. Los Alamos Natl Lab, Los Alamos, NM USA. CEA, Ctr Etud Limeil Valenton, Villeneuve St Georges, France. Max Planck Inst Quantum Opt, Garching, Germany. RP Willi, O (reprint author), Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London, England. EM o.willi@ic.ac.uk RI Davies, Jonathan/J-2611-2012; Borghesi, Marco/K-2974-2012; MacKinnon, Andrew/P-7239-2014; pukhov, alexander/C-8082-2016 OI MacKinnon, Andrew/0000-0002-4380-2906; NR 12 TC 9 Z9 9 U1 0 U2 3 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAR PY 2000 VL 40 IS 3Y SI 3 BP 537 EP 545 DI 10.1088/0029-5515/40/3Y/314 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500015 ER PT J AU Ono, M Kaye, SM Peng, YKM Barnes, G Blanchard, W Carter, MD Chrzanowski, J Dudek, L Ewig, R Gates, D Hatcher, RE Jarboe, T Jardin, SC Johnson, D Kaita, R Kalish, M Kessel, CE Kugel, HW Maingi, R Majeski, R Manickam, J McCormack, B Menard, J Mueller, D Nelson, BA Nelson, BE Neumeyer, C Oliaro, G Paoletti, F Parsells, R Perry, E Pomphrey, N Ramakrishnan, S Raman, R Rewoldt, G Robinson, J Roquemore, AL Ryan, P Sabbagh, S Swain, D Synakowski, EJ Viola, M Williams, M Wilson, JR AF Ono, M Kaye, SM Peng, YKM Barnes, G Blanchard, W Carter, MD Chrzanowski, J Dudek, L Ewig, R Gates, D Hatcher, RE Jarboe, T Jardin, SC Johnson, D Kaita, R Kalish, M Kessel, CE Kugel, HW Maingi, R Majeski, R Manickam, J McCormack, B Menard, J Mueller, D Nelson, BA Nelson, BE Neumeyer, C Oliaro, G Paoletti, F Parsells, R Perry, E Pomphrey, N Ramakrishnan, S Raman, R Rewoldt, G Robinson, J Roquemore, AL Ryan, P Sabbagh, S Swain, D Synakowski, EJ Viola, M Williams, M Wilson, JR CA NSTX Team TI Exploration of spherical torus physics in the NSTX device SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA ID TOKAMAK; PLASMAS; BETA AB The National Spherical Torus Experiment (NSTX) is being built at Princeton Plasma Physics Laboratory to test the fusion physics principles for the spherical torus concept at the MA level. The NSTX nominal plasma parameters are R-o = 85 cm; a = 67 cm, R/a greater than or equal to 1.26, B-t = 3 kG, I-p = 1 MA, q(95) = 14, elongation k less than or equal to 2.2, triangularity delta less than or equal to 0.5 and a plasma pulse length of up to 5 s. The plasma heating/current drive tools are high harmonic fast wave (6 MW, 5 s), neutral beam injection (5 MW, 80 keV, 5 s) and coaxial helicity injection. Theoretical calculations predict that NSTX should provide exciting possibilities for exploring a number of important new physics regimes, including very high plasma beta, naturally high plasma elongation, high bootstrap current fraction, absolute magnetic well and high pressure driven sheared flow. In addition, the NSTX programme plans to explore fully non-inductive plasma startup as well as a dispersive scrape-off layer for heat and particle flux handling. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Washington, Seattle, WA 98195 USA. Columbia Univ, New York, NY USA. RP Ono, M (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Jardin, Stephen/E-9392-2010; pomphrey, neil/G-4405-2010; Sabbagh, Steven/C-7142-2011; OI Menard, Jonathan/0000-0003-1292-3286 NR 11 TC 293 Z9 293 U1 2 U2 16 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 MAR PY 2000 VL 40 IS 3Y SI 3 BP 557 EP 561 DI 10.1088/0029-5515/40/3Y/316 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500017 ER PT J AU Spong, DA Hirshman, SP Whitson, JC Batchelor, DB Sanchez, R Carreras, BA Lynch, VE Lyon, JF Valanju, PM Miner, WH Moroz, PE Zarnstorff, MC Monticello, DA Ware, AS Garcia, L AF Spong, DA Hirshman, SP Whitson, JC Batchelor, DB Sanchez, R Carreras, BA Lynch, VE Lyon, JF Valanju, PM Miner, WH Moroz, PE Zarnstorff, MC Monticello, DA Ware, AS Garcia, L TI Design studies of low aspect ratio quasi-omnigenous stellarators SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA ID OPTIMIZATION; TRANSPORT; DEVICES; FIELDS AB Significant progress has been made in the development of new, compact stellarator devices that could test optimization principles for the design of a more attractive reactor. These are 3 and 4 field period low aspect ratio quasi-omnigenous stellarators based on an optimization method that aims at improved confinement, stability, ease of coil design, low aspect ratio and low bootstrap current. With respect to the analysis of these devices, the authors have developed improved measures of neoclassical transport, collisionless loss analyses of ICRF tail and ct population confinement and methods for the rapid assessment of ballooning stability boundaries. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Texas, Austin, TX 78712 USA. Univ Wisconsin, Madison, WI USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Montana, Missoula, MT 59812 USA. Univ Carlos III Madrid, Madrid, Spain. RP Spong, DA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Sanchez, Raul/C-2328-2008; Garcia, Luis/A-5344-2015; Spong, Donald/C-6887-2012; Lynch, Vickie/J-4647-2012 OI Garcia, Luis/0000-0002-0492-7466; Spong, Donald/0000-0003-2370-1873; Lynch, Vickie/0000-0002-5836-7636 NR 14 TC 5 Z9 5 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 MAR PY 2000 VL 40 IS 3Y SI 3 BP 563 EP 567 DI 10.1088/0029-5515/40/3Y/317 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500018 ER PT J AU Lee, GS Kim, J Hwang, SM Chang, CS Chang, HY Cho, MH Choi, BH Kim, K Cho, KW Cho, S Choh, KK Choi, CH Choi, JH Choi, JW Choi, IS Do, CJ Ha, TH Han, JH Hong, JS Hong, KH Hur, NI Hwang, IS Im, KH Jhang, HG Jung, YS Kim, BC Kim, DL Kim, GH Kim, HS Kim, JS Kim, JY Kim, WC Kim, YS Kwon, KH Kyum, MC Lee, BJ Lee, DK Lee, HG Lee, JM Lee, SG Na, HG Oh, YK Park, JH Ri, HC Ryoo, YS Song, KY Yang, HL Yang, JG Yoo, BJ Yoo, SJ Yoon, NS Yoon, SB You, GH You, KI Choe, W Choi, DI Jeong, SG Lee, DY Bae, YS Kang, HS Kim, GN Ko, IS Namkung, W Oh, JS Bae, YD Cho, YS Hong, BG Hong, G Hwang, CK In, SR Ju, MH Lee, HJ Oh, BH Yoon, BJ Baang, S Choi, HJ Hwang, J Kim, MG Kim, YJ Lee, SI Yee, J Yoon, CS Chung, KH Hong, SH Hwang, YS Kim, SH Kim, YH Chung, KH Lim, JY Ha, DW Oh, SS Ryu, KS Wang, QL Ko, TK Joo, J Suh, S Choi, CH Lee, JH Lee, YW Shin, HS Song, IH Baek, J Han, IY Koh, Y Park, PY Ryu, C Cho, JJ Hwang, DM Kim, YS Schmidt, JA Park, HK Neilson, GH Reiersen, WT Simmons, RT Bernabei, S Dahlgren, F Grisham, LR Jardin, SC Kessel, CE Manickam, J Medley, SS Pomphrey, N Sinnis, JC Brown, TG White, RB Young, KM Schultz, J Wang, PW Sevier, L Carter, MD Ryan, PM Swain, DW Hill, DN Nevins, WM Braams, BJ AF Lee, GS Kim, J Hwang, SM Chang, CS Chang, HY Cho, MH Choi, BH Kim, K Cho, KW Cho, S Choh, KK Choi, CH Choi, JH Choi, JW Choi, IS Do, CJ Ha, TH Han, JH Hong, JS Hong, KH Hur, NI Hwang, IS Im, KH Jhang, HG Jung, YS Kim, BC Kim, DL Kim, GH Kim, HS Kim, JS Kim, JY Kim, WC Kim, YS Kwon, KH Kyum, MC Lee, BJ Lee, DK Lee, HG Lee, JM Lee, SG Na, HG Oh, YK Park, JH Ri, HC Ryoo, YS Song, KY Yang, HL Yang, JG Yoo, BJ Yoo, SJ Yoon, NS Yoon, SB You, GH You, KI Choe, W Choi, DI Jeong, SG Lee, DY Bae, YS Kang, HS Kim, GN Ko, IS Namkung, W Oh, JS Bae, YD Cho, YS Hong, BG Hong, G Hwang, CK In, SR Ju, MH Lee, HJ Oh, BH Yoon, BJ Baang, S Choi, HJ Hwang, J Kim, MG Kim, YJ Lee, SI Yee, J Yoon, CS Chung, KH Hong, SH Hwang, YS Kim, SH Kim, YH Chung, KH Lim, JY Ha, DW Oh, SS Ryu, KS Wang, QL Ko, TK Joo, J Suh, S Choi, CH Lee, JH Lee, YW Shin, HS Song, IH Baek, J Han, IY Koh, Y Park, PY Ryu, C Cho, JJ Hwang, DM Kim, YS Schmidt, JA Park, HK Neilson, GH Reiersen, WT Simmons, RT Bernabei, S Dahlgren, F Grisham, LR Jardin, SC Kessel, CE Manickam, J Medley, SS Pomphrey, N Sinnis, JC Brown, TG White, RB Young, KM Schultz, J Wang, PW Sevier, L Carter, MD Ryan, PM Swain, DW Hill, DN Nevins, WM Braams, BJ TI The KSTAR project: An advanced steady state superconducting tokamak experiment SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA AB The Korea Superconducting Tokamak Advanced Research (KSTAR) project is the major effort of the national fusion programme of the Republic of Korea. Its aim is to develop a steady state capable advanced superconducting tokamak to establish a scientific and technological basis for an attractive fusion reactor. The major parameters of the tokamak are: major radius 1.8 mi minor radius 0.5 m. toroidal held 3.5 T and plasma current 2 MA, with a strongly shaped plasma cross-section and double null divertor. The initial pulse length provided by the poloidal magnet system is 20 s, but the pulse length can be increased to 300 s through non-inductive current drive. The plasma heating and current drive system consists of neutral beams? ion cyclotron waves, lower hybrid waves and electron cyclotron waves for flexible profile control in advanced tokamak operating modes. A comprehensive set of diagnostics is planned for plasma control, performance evaluation and physics understanding. The project has completed its conceptual design and moved to the engineering design and construction phase. The target date for the first plasma is 2002. C1 Korea Basic Sci Inst, Natl Fus Res & Dev Ctr, Taejon, South Korea. Korea Adv Inst Sci & Technol, Taejon 305701, South Korea. Pohang Univ Sci & Technol, Pohang, South Korea. Korea Atom Energy Res Inst, Taejon, South Korea. Samsung Adv Inst Technol, Taejon, South Korea. Seoul Natl Univ, Seoul, South Korea. Korea Res Inst Stand & Sci, Taejon, South Korea. Korea Electrotechnol Res Inst, Changwon, South Korea. Yonsei Univ, Seoul 120749, South Korea. Sungkyunkoan Univ, Seoul, South Korea. POSCON Corp, Pohang, South Korea. Dae Sung Cable Co, Seoul, South Korea. Korea Iron Steel Wire Ltd, Seoul, South Korea. CVE Corp, Seoul, South Korea. Samsung Aerosp Corp, Changwon, South Korea. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. MIT, Cambridge, MA 02139 USA. Gen Atom Co, San Diego, CA USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. NYU, New York, NY USA. RP Lee, GS (reprint author), Korea Basic Sci Inst, Natl Fus Res & Dev Ctr, Taejon, South Korea. RI Jardin, Stephen/E-9392-2010; pomphrey, neil/G-4405-2010; Choe, Wonho/C-1556-2011; Chang, Hong-Young/C-1964-2011; Braams, Bastiaan/E-7687-2011; Hwang, Yong-Seok/D-8347-2012; White, Roscoe/D-1773-2013 OI Braams, Bastiaan/0000-0003-4086-9969; White, Roscoe/0000-0002-4239-2685 NR 5 TC 129 Z9 130 U1 3 U2 15 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 MAR PY 2000 VL 40 IS 3Y SI 3 BP 575 EP 582 DI 10.1088/0029-5515/40/3Y/319 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500020 ER PT J AU Peng, YKM Reiersen, W Kaye, SM Jardin, SC Menard, J Gates, D Robinson, J Dahlgren, F Grisham, LR Majeski, R Mikkelsen, DR Ono, M Schmidt, JA Wilson, JR Woolley, R Cheng, ET Cerbone, RJ Strickler, DJ Galambos, JD Sviatoslavsky, IN Shaing, KC Wang, X AF Peng, YKM Reiersen, W Kaye, SM Jardin, SC Menard, J Gates, D Robinson, J Dahlgren, F Grisham, LR Majeski, R Mikkelsen, DR Ono, M Schmidt, JA Wilson, JR Woolley, R Cheng, ET Cerbone, RJ Strickler, DJ Galambos, JD Sviatoslavsky, IN Shaing, KC Wang, X TI Science and technology of the 10 MA spherical tori SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA ID TOKAMAK PLASMAS; NEUTRON SOURCE AB The scientific parameters and the technology issues for a modest size spherical torus (ST) at 10 MA plasma current are discussed. This class of devices includes a DT-capable ST experiment (DTST, R-o = 1.2 m) for extended plasma performance tests for limited pulse lengths and neutron fluences, and a volume neutron source (VNS, R-o = 1.1 m) for steady state energy technology testing to high neutron fluences. The scientific issues of interest for DTST include non-inductive ramp-up of plasma current on a limited timescale (similar to 30 s), the confinement needed for high Q burn, the behaviour of energetic particles, the physics and techniques to handle intense plasma exhaust, and the possibility of high performance plasma regimes free of disruptions or large disruption impact. Of further interest for the VNS would be steady state operation using large external current drive, possibly at a modest Q (similar to 1-2), achieving significant neutron wall loading (similar to 1 MW/m(2)) and a configuration relatively amenable to remote maintenance. A much longer timescale would be permitted in a VNS for noninductive current ramp-up. The centre leg of the toroidal field coils, possibly multiturn for DTST and necessarily single turn for a VNS without significant nuclear shielding, presents technical and material issues of unique importance to the ST. Positive ion neutral beam injection and high harmonic fast wave (similar to 80 MHz) heating and current drive systems already available are likely to be adequate for DTST following pulse length extension to similar to 50 s. Given an adequate physics database, the remaining enabling technologies needed for the VNS appear largely similar in nature to those of the ITER EDA design. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. TSI Res Inc, Solana Beach, CA USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Wisconsin, Madison, WI USA. Univ Texas, Austin, TX 78712 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. RP Peng, YKM (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Jardin, Stephen/E-9392-2010; OI Menard, Jonathan/0000-0003-1292-3286 NR 23 TC 3 Z9 3 U1 1 U2 2 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAR PY 2000 VL 40 IS 3Y SI 3 BP 583 EP 587 DI 10.1088/0029-5515/40/3Y/320 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500021 ER PT J AU Moslang, A Ehrlich, K Shannon, TE Rennich, MJ Jameson, RA Kondo, T Katsuta, H Maekawa, H Martone, M Teplyakov, V AF Moslang, A Ehrlich, K Shannon, TE Rennich, MJ Jameson, RA Kondo, T Katsuta, H Maekawa, H Martone, M Teplyakov, V TI Suitability and feasibility of the International Fusion Materials Irradiation Facility (IFMIF) for fusion materials studies SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA ID DESIGN AB There is a global consensus among materials scientists and engineers that the qualification of materials in an appropriate test environment is indispensable for the design, construction and safe operation of demonstration fusion reactors as well as for the calibration of data generated from fission reactor and accelerator irradiations. In an evaluation process based on a series of technical workshops it was concluded that an accelerator driven D-Li stripping source would be the best choice to fulfil the requirements within a realistic time frame. In response to this need, an international design team with members from the European Union, Japan, the United States of America and the Russian Federation has developed, under the auspices of the International Energy Agency during a conceptual design activity phase (1994-1996), a suitable and feasible concept for an accelerator driven D-Li stripping source. This reference design for the International Fusion Materials Irradiation Facility (IFMIF) is based on conservative linac technology and two parallel operating 125 mA, 40 MeV deuteron beams that are focused onto a common liquid Li target with a beam footprint of 50 mm by 200 mm. The materials testing volume behind the Li target is subdivided into different flux regions: the high flux test region (0.5 L, 20-55 dpa/full power year), the medium flux test region (6 L, 1-20 dpa/full power year), and the low flux test region (>100 L, <1 dpa/full power year). The design developed was the basis for the conceptual design evaluation phase (1997-1998) and for subsequent engineering oriented activities. On the basis of comprehensive neutron transport calculations, an evaluation of the irradiation parameters and the available testing volumes has shown that the users' requirements can be fulfilled. Major engineering efforts have been undertaken to establish an IFMIF design that is based on available and already proven technologies. The design developed is based on extensive reliability availability, maintainability and safety studies and is conceived for long term operation with a total annual facility availability of at least 70%. C1 Euratom FZK Assoc, Forschungszentrum Karlsruhe, Karlsruhe, Germany. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. ENEA, Ctr Ric Frascati, Frascati, Italy. Inst High Energy Phys, Protvino, Russia. Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. RP Moslang, A (reprint author), Euratom FZK Assoc, Forschungszentrum Karlsruhe, Karlsruhe, Germany. OI Rennich, Mark/0000-0001-6945-0075 NR 15 TC 17 Z9 17 U1 0 U2 2 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAR PY 2000 VL 40 IS 3Y SI 3 BP 619 EP 627 DI 10.1088/0029-5515/40/3Y/324 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500025 ER PT J AU Dimits, AM Cohen, BI Mattor, N Nevins, WM Shumaker, DE Parker, SE Kim, C AF Dimits, AM Cohen, BI Mattor, N Nevins, WM Shumaker, DE Parker, SE Kim, C TI Simulation of ion temperature gradient turbulence in tokamaks SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA ID GYROKINETIC SIMULATIONS; FLUID SIMULATIONS; DRIVEN; MODES AB Results are presented from non-linear gyrokinetic simulations of toroidal ion temperature gradient turbulence and transport. The ion thermal fluxes are found to have an offset linear dependence on the temperature gradient and are significantly lower than gyrofluid or IFS-PPPL model predictions. A new phenomenon of non-linear effective critical gradients larger than the linear instability threshold gradients is observed and is associated with undamped flux surface averaged shear flows. The nonlinear gyrokinetic codes have passed extensive tests, including comparison against independent linear calculations, a series of non-linear convergence tests and a comparison between two independent nonlinear gyrokinetic codes. The most realistic simulations to date used actual reconstructed equilibria from experiments and a model for dilution by impurity and beam ions. These simulations highlight the importance of both self-generated and external E x B flow shear as well as the need for still more physics to be included. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Colorado, Boulder, CO 80309 USA. RP Dimits, AM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 18 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 MAR PY 2000 VL 40 IS 3Y SI 3 BP 661 EP 666 DI 10.1088/0029-5515/40/3Y/329 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500030 ER PT J AU Kotschenreuther, M Dorland, W Liu, QP Zarnstorff, MC Miller, RL Lin-Liu, YR AF Kotschenreuther, M Dorland, W Liu, QP Zarnstorff, MC Miller, RL Lin-Liu, YR TI Attaining neoclassical transport in ignited tokamaks SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA ID ASPECT-RATIO TOKAMAKS; STABILITY; BARRIERS; PLASMAS; SHEAR; INSTABILITIES; SIMULATIONS; CONFINEMENT; TURBULENCE; EQUILIBRIA AB The requirements to stabilize microinstabilities with velocity shear in tokamaks are examined for both aspect ratio A = 3 and A = 1.4. A comprehensive linear gyrokinetic code is used to compute growth rates in realistic numerical equilibria. Growth rates for A = 3 and A = 1.4 are generally similar for electron drift modes and ion temperature gradient modes. Velocity shear is stronger at low aspect ratio; how-ever, low A profiles have a stronger microtearing mode which is more difficult to shear stabilize. Nonetheless, low aspect ratio devices are predicted to have good confinement and may ignite at very small size. Profiles are presented which may allow high beta, MHD stable operation at A = 1.4 with high confinement. The possibility of using a controlled application of non-turbulent loss processes to control profiles to prevent turbulent transport and to maximize beta is suggested. C1 Univ Texas, Inst Fus Studies, Austin, TX 78712 USA. Univ Maryland, Inst Plasma Phys, College Pk, MD 20742 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Gen Atom Co, San Diego, CA USA. RP Kotschenreuther, M (reprint author), Univ Texas, Inst Fus Studies, Austin, TX 78712 USA. RI Dorland, William/B-4403-2009 OI Dorland, William/0000-0003-2915-724X NR 26 TC 39 Z9 39 U1 0 U2 2 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAR PY 2000 VL 40 IS 3Y SI 3 BP 677 EP 684 DI 10.1088/0029-5515/40/3Y/331 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500032 ER PT J AU Xu, XQ Cohen, RH Porter, GD Rognlien, TD Ryutov, DD Myra, JR D'Ippolito, DA Moyer, RA Groebner, RJ AF Xu, XQ Cohen, RH Porter, GD Rognlien, TD Ryutov, DD Myra, JR D'Ippolito, DA Moyer, RA Groebner, RJ TI Turbulence studies in tokamak boundary plasmas with realistic divertor geometry SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA ID SCRAPE-OFF-LAYER AB Results are presented from the 3-D non-local electromagnetic turbulence code BOUT and the linearized shooting code BAL for studies of turbulence in tokamak boundary plasmas and its relationship to the GH transition, in a realistic divertor plasma geometry. The key results include: (1) the identification of the dominant resistive X point mode in divertor geometry; (2) turbulence suppression in the L-H transition by shear in the E x B drift velocity, ion diamagnetism and finite polarization; (3) the fact that calculated values of the thermal diffusivities such as Xi are comparable to those inferred from the experimentally measured plasma density and temperature profiles. On the basis of simulation results, a parameterization of the transport is given that includes the dependence on the relevant physical parameters. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Lodestar Res Corp, Boulder, CO USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Gen Atom Co, San Diego, CA USA. RP Xu, XQ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 10 TC 33 Z9 33 U1 2 U2 8 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 MAR PY 2000 VL 40 IS 3Y SI 3 BP 731 EP 736 DI 10.1088/0029-5515/40/3Y/339 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500040 ER PT J AU Lin, Z Chance, MS Hahm, TS Krommes, JA Lee, WW Manuilskiy, I Mynick, HE Qin, H Rewoldt, G Tang, WM White, RB AF Lin, Z Chance, MS Hahm, TS Krommes, JA Lee, WW Manuilskiy, I Mynick, HE Qin, H Rewoldt, G Tang, WM White, RB TI Numerical and theoretical studies of turbulence and transport with E x B shear flows SO NUCLEAR FUSION LA English DT Article; Proceedings Paper CT 17th IAEA Fusion Energy Conference CY OCT 19-24, 1998 CL YOKOHAMA, JAPAN SP IAEA ID POLOIDAL ROTATION; PLASMAS; SIMULATIONS; TOKAMAKS AB A report is given of: (a) a substantial transport reduction by the turbulence driven E x B flows observed in three dimensional non-linear gyrokinetic simulations of microturbulence in magnetically confined toroidal plasmas, (b) an analytical derivation of the effective shearing rate for the time dependent E x B flow; (c) an interpretation of experimental data using linear gyrokinetic microinstability rotation models of E x B shear; (d) other developments in gyrokinetic theory and simulation. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Lin, Z (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI White, Roscoe/D-1773-2013 OI White, Roscoe/0000-0002-4239-2685 NR 16 TC 0 Z9 0 U1 0 U2 4 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 MAR PY 2000 VL 40 IS 3Y SI 3 BP 737 EP 741 DI 10.1088/0029-5515/40/3Y/340 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 302GZ UT WOS:000086358500041 ER PT J AU Elias, J Klimenko, S Konigsberg, J Korytov, A Mitselmakher, G Nomerotski, A Northacker, D Safonov, A Vidal, R AF Elias, J Klimenko, S Konigsberg, J Korytov, A Mitselmakher, G Nomerotski, A Northacker, D Safonov, A Vidal, R TI Luminosity monitor based on Cherenkov counters for p(p)over-bar colliders SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE luminosity; Cherenkov counter; p(p)over-bar collider AB We describe here a novel approach to luminosity measurements for p (p) over bar collider experiments. We propose to use low-pressure gaseous Cherenkov counters at small angles relative to the beam direction to determine the rate of inelastic p (p) over bar interactions. With a propotype counter, we measured at a beam test a light yield of over 100 photoelectrons and a timing resolution of better than 50 ps. The CDF collaboration will use a detector based on this technique for luminosity measurements at the upgraded Tevatron collider. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. RP Nomerotski, A (reprint author), Fermi Natl Accelerator Lab, Mail Stop 318,POB 500, Batavia, IL 60510 USA. RI Nomerotski, Andrei/A-5169-2010 NR 6 TC 18 Z9 18 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 MAR 1 PY 2000 VL 441 IS 3 BP 366 EP 373 DI 10.1016/S0168-9002(99)00973-0 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 295JH UT WOS:000085962600008 ER PT J AU Rachinhas, PJBM Simoes, PCPS Lopes, JAM Dias, THVT Morgado, RE dos Santos, JMF Stauffer, AD Conde, CAN AF Rachinhas, PJBM Simoes, PCPS Lopes, JAM Dias, THVT Morgado, RE dos Santos, JMF Stauffer, AD Conde, CAN TI Simulation and experimental results for the detection of conversion electrons with gas proportional scintillation counters SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE gas scintillation detectors; conversion electrons; Monte Carlo simulation; digital pulse processing ID MONTE-CARLO SIMULATION; X-RAY SPECTROMETRY; CROSS-SECTIONS; TRANSPORT PARAMETERS; XENON; PHOTOIONIZATION; PERFORMANCE; SPECTROSCOPY; ABSORPTION; SCATTERING AB The application of gas proportional scintillation counters (GPSC) to the detection and identification of conversion electrons in the medium energy range is investigated. Experimental and Monte Carlo results are presented for the response of a xenon GPSC, filled at atmospheric pressure, to the decay of a Cd-109 source. This source emits 88.0 keV gamma-rays, e(L) = 84.6 keV and e(K) = 62.5 keV conversion electrons, as well as fluorescence X-rays and Auger electrons. Good agreement is found between the measured and the calculated energy spectra. The response to higher-energy electrons is investigated by Monte Carlo simulation, by considering a hypothetical GPSC filled with xenon at 10 atm and doped with the Xe-133m metastable isotope. The calculated energy spectra for the absorption of the Xe-133m 233.2keV gamma-rays, e(K) = 198.6keV and e(L) = 228.4keV conversion electrons, as well as fluorescence X-rays and Auger electrons, are presented and discussed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Coimbra, Dept Fis, P-3004516 Coimbra, Portugal. Inst Super Engn Coimbra, P-3001601 Coimbra, Portugal. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. York Univ, Dept Phys & Astron, Toronto, ON M3J 1P3, Canada. RP Rachinhas, PJBM (reprint author), Univ Coimbra, Dept Fis, P-3004516 Coimbra, Portugal. RI matias-lopes, jose/H-6074-2012; dos Santos, Joaquim/B-3058-2015; OI matias-lopes, jose/0000-0002-6366-2963; Dias, Teresa/0000-0001-5101-4902; Conde, Carlos/0000-0002-1387-2161; dos Santos, Joaquim Marques Ferreira/0000-0002-8841-6523 NR 48 TC 11 Z9 12 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 MAR 1 PY 2000 VL 441 IS 3 BP 468 EP 478 DI 10.1016/S0168-9002(99)00978-X PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 295JH UT WOS:000085962600016 ER PT J AU Bowyer, TW Geelhood, BD Hossbach, TW Hansen, R Wilcox, WA AF Bowyer, TW Geelhood, BD Hossbach, TW Hansen, R Wilcox, WA TI In situ, high sensitivity, measurement of (90)strontium in ground water using Cherenkov light SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB The measurement of Sr-90 in soils and ground water is important for characterization and remediation of radioactively contaminated sites. Measuring the Sr-90 content to a few pCi/g of soil has been accomplished based on a design of scintillating fibers in a multilayered configuration measuring the high-energy beta emitted from Y-90 decay (when in secular equilibrium with Sr-90), but has not been applied to water because the technique is sensitive to only the first few mm of soil. The volume of the source to which the detector is sensitive limits the theoretical sensitivity of such a detector, unless chemical preprocessing to strip the Sr-90 from the water is performed. Sr-90 activity in water can be quantified by detecting the high-energy beta particle by the Cherenkov light it produces when the high-energy beta from Y-90 passes through the medium. We have used this phenomenon to sensitively measure Sr-90 (Y-90) from a volume of water large enough (765 cm(3)) to make very sensitive measurements with short count limes. For counting intervals of about 1000 s, we were able to achieve a minimum detectable concentration (MDC) (at 4.65 sigma above background) of 14 pCi/L, and for 3000 s counts the MDC dropped to the drinking water limit of 8 pCi/L. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Bowyer, TW (reprint author), Pacific NW Lab, POB 999,902 Battelle Blvd, Richland, WA 99352 USA. NR 3 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 MAR 1 PY 2000 VL 441 IS 3 BP 577 EP 582 DI 10.1016/S0168-9002(99)00975-4 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 295JH UT WOS:000085962600029 ER PT J AU Peshkin, M AF Peshkin, M TI A no-go theorem for matter-wave interferometry with application to the neutron's electric-dipole moment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE matter-wave interferometry; neutron electric-dipole moment ID INTERFERENCE AB A general theorem for matter-wave interferometry that relies only on the unitary property of the Schroedinger equation and not upon any classical or semi-classical approximation restricts the benefits of using long drift spaces. In particular, it negates some, but not all, suggestions that have been made for measuring the neutron's electric-dipole moment by interferometry. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Peshkin, M (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 10 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 MAR 1 PY 2000 VL 441 IS 3 BP 583 EP 587 DI 10.1016/S0168-9002(99)00989-4 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 295JH UT WOS:000085962600030 ER PT J AU Schenkel, T Newman, MW Niedermayr, TR Machicoane, GA McDonald, JW Barnes, AV Hamza, AV Banks, JC Doyle, BL Wu, KJ AF Schenkel, T Newman, MW Niedermayr, TR Machicoane, GA McDonald, JW Barnes, AV Hamza, AV Banks, JC Doyle, BL Wu, KJ TI Electronic sputtering of solids by slow, highly charged ions: Fundamentals and applications SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 14th International Conference on Ion Beam Analysis/6th European Conference on Accelerators in Applied Research and Technology CY JUL 26-30, 1999 CL DRESDEN, GERMANY SP Res Ctr Rossendorf, Inst Ion Beam Phys & Mat Res DE electronic sputtering; highly charged ions; surface analysis; coincidences ID BACKSCATTERING SPECTROMETRY HIBS; MASS-SPECTROMETRY; STIMULATED DESORPTION; THIN-FILMS; EMISSION; SURFACES; SILICON; EXCITATION; GAAS; MICROSCOPY AB Electronic sputtering in the interaction of slow (v < V-Bohr), highly charged ions (SHCI) with solid surfaces has been subject of controversial discussions for almost 20 years. We review results from recent studies of total sputtering yields and discuss distinct microscopic mechanisms (such as defect mediated desorption, Coulomb explosions and effects of intense electronic excitation) in the response of insulators and semiconductors to the impact of SHCI. We then describe an application of ions like Xe44+ and AU(69+) as projectiles in time-of-flight secondary ion mass spectrometry for surface characterization of semiconductors. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Charles Evans & Associates, Redwood City, CA 94063 USA. RP Schenkel, T (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. EM schenkel@llnl.gov NR 60 TC 20 Z9 21 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAR PY 2000 VL 161 BP 65 EP 75 DI 10.1016/S0168-583X(99)00880-0 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 299NE UT WOS:000086204100009 ER PT J AU Browning, JF Langley, RA Doyle, BL Banks, JC Wampler, WR AF Browning, JF Langley, RA Doyle, BL Banks, JC Wampler, WR TI High accuracy, high energy He-ERD analysis of H, D and T SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 14th International Conference on Ion Beam Analysis/6th European Conference on Accelerators in Applied Research and Technology CY JUL 26-30, 1999 CL DRESEDEN, GERMANY SP Res Ctr Rossendorf, Inst Ion Beam Phys & Mat Res DE elastic recoil detection; elastic scattering cross-sections; hydrogen isotopes AB A new analysis technique using high-energy helium ions for the simultaneous elastic recoil detection of all three hydrogen isotopes in metal hydride systems extending to depths of several mu m's is presented. Analysis shows that it is possible to separate each hydrogen isotope in a heavy matrix such as erbium to depths of 5 mu m using incident 11.48 MeV He-4 ions with a detection system composed of a range foil and Delta E - E telescope detector. Newly measured cross-sections for the elastic recoil scattering of He-4 ions from protons and deuterons are presented in the energy range 10-11.75 MeV for the laboratory recoil angle of 30 degrees. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Browning, JF (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. OI Browning, James/0000-0001-8379-259X NR 14 TC 16 Z9 17 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAR PY 2000 VL 161 BP 211 EP 215 DI 10.1016/S0168-583X(99)00893-9 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 299NE UT WOS:000086204100036 ER PT J AU Font, AC Banks, JC Doyle, BL AF Font, AC Banks, JC Doyle, BL TI Quantitative analysis with heavy ion E-TOF-ERD SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 14th International Conference on Ion Beam Analysis/6th European Conference on Accelerators in Applied Research and Technology CY JUL 26-30, 1999 CL DRESEDEN, GERMANY SP Res Ctr Rossendorf, Inst Ion Beam Phys & Mat Res DE heavy ion elastic recoil detection; E-TOF-ERD; quantification of E-TOF-ERD spectra ID ELASTIC RECOIL DETECTION; TIME-OF-FLIGHT; LIGHT-ELEMENTS; TRANSPORT; HYDROGEN; H-1 AB Moderate-velocity heavy ion TOF-ERD combined with energy detection (E-TOF-ERD) is a powerful analytical technique, with large cross sections (similar to 10(-21) cm(2)/sr), high depth resolution (similar to 2 nm), and good mass resolution (similar to 1 amu). Measurements on several oxides were performed with the E-TOF-ERD system at Sandia National Laboratories using 10-15 MeV Au and 6.5 MeV I incident beams. Commercially available multi-parameter acquisition software was used for data collection. Quantitative information about the composition of the oxide samples was obtained by converting the time domain spectra into the energy domain and analyzed with the computer simulation code, SIMNRA. Use of these acquisition and simulation software codes will be discussed. Several problems associated with the use of moderate-velocity heavy ion E-TOF-ERD were identified during measurement and analysis of the oxide samples. These include (1) difficulty in accurately measuring the beam dose, (2) unreliable tabulated stopping powers for heavy ions, and (3) erosion of some thin oxides by Coulomb explosions caused by the beam. These problems are also discussed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Autonoma Madrid, Dept Fis Aplicada C12, ES-28049 Madrid, Spain. Univ Autonoma Madrid, Inst Nicolas Cabrera, ES-28049 Madrid, Spain. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Font, AC (reprint author), Univ Autonoma Madrid, Dept Fis Aplicada C12, ES-28049 Madrid, Spain. RI Climent-Font, Aurelio/G-8449-2016 NR 16 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAR PY 2000 VL 161 BP 255 EP 259 DI 10.1016/S0168-583X(99)00854-X PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 299NE UT WOS:000086204100045 ER PT J AU Bianconi, M Abel, F Banks, JC Font, AC Cohen, C Doyle, BL Lotti, R Lulli, G Nipoti, R Vickridge, I Walsh, D Wendler, E AF Bianconi, M Abel, F Banks, JC Font, AC Cohen, C Doyle, BL Lotti, R Lulli, G Nipoti, R Vickridge, I Walsh, D Wendler, E TI The Si surface yield as a calibration standard for RBS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 14th International Conference on Ion Beam Analysis/6th European Conference on Accelerators in Applied Research and Technology CY JUL 26-30, 1999 CL DRESEDEN, GERMANY SP Res Ctr Rossendorf, Inst Ion Beam Phys & Mat Res DE Rutherford backscattering spectrometry; calibration standards; stopping power; silicon ID RUTHERFORD BACKSCATTERING; SIMULATION AB The Rutherford backscattering spectroscopy (RBS) surface height of a pure bulk material can be used as an absolute standard Value to calibrate the detector solid angle. This work presents the results of an international collaboration started at the beginning of 1998 to define the surface height of the RES spectrum (H-0) of Si, amorphized by ion implantation to avoid channeling. The analyses were performed with 1-3 MeV He beams and 170 degrees scattering angle. The detector solid angle was estimated in the different laboratories either by geometrical measurement or by a calibrated standard. The agreement of the experimental Ho Values is of the order +/-2%, the claimed accuracy for RES. The results are also consistent at 2% level with both the stopping power measurements of Konac et al. (1998), and the measurements of Lennard et al. (1999). (C) 2000 Elsevier Science B.V. All rights reserved. C1 CNR, Ist Lamel, I-40129 Bologna, Italy. GPS, Paris, France. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Autonoma Madrid, E-28049 Madrid, Spain. Univ Jena, Inst Festkorperphys, D-6900 Jena, Germany. RP Bianconi, M (reprint author), CNR, Ist Lamel, Via Gobetti 101, I-40129 Bologna, Italy. RI Vickridge, Ian/E-4266-2010; Lulli, Giorgio/N-6203-2014; Nipoti, Roberta/N-6162-2014; Bianconi, Marco/P-5637-2014; Climent-Font, Aurelio/G-8449-2016 OI Lulli, Giorgio/0000-0002-1222-367X; Nipoti, Roberta/0000-0002-8019-9149; Bianconi, Marco/0000-0001-5742-7839; NR 17 TC 26 Z9 26 U1 1 U2 12 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 MAR PY 2000 VL 161 BP 293 EP 296 DI 10.1016/S0168-583X(99)00927-1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 299NE UT WOS:000086204100052 ER PT J AU Doyle, BL Vizkelethy, G Walsh, DS AF Doyle, BL Vizkelethy, G Walsh, DS TI Ion beam induced charge collection (IBICC) studies of cadmium zinc telluride (CZT) radiation detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 14th International Conference on Ion Beam Analysis/6th European Conference on Accelerators in Applied Research and Technology CY JUL 26-30, 1999 CL DRESDEN, GERMANY SP Res Ctr Rossendorf, Inst Ion Beam Phys & Mat Res AB Cadmium zinc telluride (CZT) is an emerging material for room temperature radiation detectors. In order to optimize the performance of these detectors, it is important to determine how the electronic properties of CZT are related to the presence of impurities and defects that are introduced during the crystal growth and detector fabrication. At the Sandia microbeam facility IBICC lion beam induced charge collection) and time resolved IBICC (TRIBICC) were used to image electronic properties of various CZT detectors. Two-dimensional areal maps of charge collection efficiency were deduced from the measurements. In order to determine radiation damage to the detectors, we measured the deterioration of the IBICC signal as the function of dose. A model to explain quantitatively the pattern observed in the charge collection efficiency maps of the damaged detectors has been developed and applied to the data. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Rad Solid Inter & Proc Dept, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, Rad Solid Inter & Proc Dept, MS 1056,POB 5800, Albuquerque, NM 87185 USA. EM bldoyle@sandia.gov NR 10 TC 6 Z9 6 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X EI 1872-9584 J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAR PY 2000 VL 161 BP 457 EP 461 DI 10.1016/S0168-583X(99)00929-5 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 299NE UT WOS:000086204100084 ER PT J AU Thevuthasan, S Baskaran, S Domansky, K Liu, J Engelhard, M AF Thevuthasan, S Baskaran, S Domansky, K Liu, J Engelhard, M TI Effectiveness of high energy ion beam techniques for the characterization of mesoporous low dielectric-constant materials SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 14th International Conference on Ion Beam Analysis/6th European Conference on Accelerators in Applied Research and Technology CY JUL 26-30, 1999 CL DRESEDEN, GERMANY SP Res Ctr Rossendorf, Inst Ion Beam Phys & Mat Res DE ion scattering; Rutherford backscattering spectrometry (RBS); nuclear reaction analysis (NRA); mesoporous silica materials ID LOW-DENSITY XEROGELS; LOW-K-DIELECTRICS; AMBIENT-PRESSURE; FILMS; SILICA AB Highly porous silica films can potentially reduce power dissipation, cross talk, and interconnection delay in the deep submicron regime of semiconductor devices. We have synthesized "mesoporous" silica films using both cationic and non-ionic surfactants to template porosity in spin-on sol-gel silica. During this development we have effectively used high-energy ion beam techniques along with optical profilometry to characterize the porosity of these films. Rutherford backscattering spectrometry (RBS), and O-16(d, p(1))O-17 nuclear reaction were used to determine the total number of Si and O atoms in the films. Interaction of these films with water was characterized by the H-1(F-19, alpha gamma)O-16 resonant nuclear reaction. Combination of these techniques provides fast, accurate, and quantitative methods for characterizing these films. However, the high-energy ion beams appear to cause significant damage in the films. X-ray photoelectron spectroscopy (XPS) measurements from the ion beam interacted region show a tail in the low binding energy side of the Si 2p core level spectrum which is characteristic to metal Si. In addition, craters as deep as 175 nn were left in the films where the ion beams interacted with the material. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Thevuthasan, S (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999,MSIN K8-93, Richland, WA 99352 USA. RI Engelhard, Mark/F-1317-2010; OI Engelhard, Mark/0000-0002-5543-0812 NR 20 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAR PY 2000 VL 161 BP 476 EP 481 DI 10.1016/S0168-583X(99)00816-2 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 299NE UT WOS:000086204100088 ER PT J AU Jiang, W Thevuthasan, S Weber, WJ Grotzschel, R AF Jiang, W Thevuthasan, S Weber, WJ Grotzschel, R TI Deuterium channeling analysis for He+-implanted 6H-SiC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 14th International Conference on Ion Beam Analysis/6th European Conference on Accelerators in Applied Research and Technology CY JUL 26-30, 1999 CL DRESEDEN, GERMANY SP Res Ctr Rossendorf, Inst Ion Beam Phys & Mat Res DE RBS and NRA/channeling; ion-beam-induced damage; damage recovery; 6H-SiC ID ACCUMULATION; DAMAGE AB Deuterium ion channeling is applied to study accumulated disorder on Si and C sublattices in 6H-SiC crystals irradiated with 50 keV He+ ions at 100 and 300 K. The relative disorder on both sublattices follows sigmoidal dependence on dose. Carbon disorder is higher at low doses, suggesting a smaller C displacement energy. Above an ion fluence of 1.0 x 10(16) He+/cm(2), more C defects can be recovered during irradiation, indicating a lower activation energy for C migration and recombination. Isochronal annealing data show that the recovery behavior on the Si and C sublattices is similar. Annealing of a buried amorphous SiC layer, produced at 100 K (2.5 x 10(16) He+/cm(2)), exhibits an epitaxial growth rate of similar to 0.154 nm/K in the temperature range 370-870 K. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Rossendorf Inc, Forschungszentrum Rossendorf EV, D-01314 Dresden, Germany. RP Jiang, W (reprint author), Pacific NW Lab, POB 999,MS K8-93,902 Battelle Blvd, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 12 TC 27 Z9 27 U1 0 U2 2 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 MAR PY 2000 VL 161 BP 501 EP 504 DI 10.1016/S0168-583X(99)00692-8 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 299NE UT WOS:000086204100093 ER PT J AU Thevuthasan, S McCready, DE Jiang, W Yi, SI Maheswaran, S Keefer, KD Chambers, SA AF Thevuthasan, S McCready, DE Jiang, W Yi, SI Maheswaran, S Keefer, KD Chambers, SA TI Ion beam analysis of interface reactions in magnetite and maghemite thin films SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 14th International Conference on Ion Beam Analysis/6th European Conference on Accelerators in Applied Research and Technology CY JUL 26-30, 1999 CL DRESDEN, GERMANY SP Res Ctr Rossendorf, Inst Ion Beam Phys & Mat Res DE ion scattering; Rutherford backscattering spectrometry (RBS); channeling; magnetite (Fe3O4); maghemite (gamma-Fe2O3); magnesioferrite (MgFe2O4); Mg diffusion ID EPITAXIAL-FILMS; GROWTH; FE3O4; ALPHA-FE2O3; GAMMA-FE2O3 AB We have investigated interface reactions between expitaxially-grown magnetite (Fe3O4) and maghemite (gamma-Fe2O3) films with MgO substrates using Rutherford backscattering (RBS), channeling, and X-ray diffraction (XRD), Annealing these films in 2.0x10(-6) Torr of O at temperatures up to 970 K enhances Mg outdiffusion into the films and increases the film thickness depending on temperature. The Fe3O4 film thickness reach a limiting value at 870 K anneal while the gamma-Fe2O3 film thickness did not maximize after annealing at 970 K. After the annealing at 970 K, both films produced a compound with composition close to magnesioferrite (MgFe2O4). XRD results reveal the formation of MgFe2O4 films after annealing both films at 970 K in O. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Western Sydney Nepean, Sch Sci, Kingswood, NSW 2747, Australia. RP Thevuthasan, S (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999,MSIN K2-12, Richland, WA 99352 USA. EM theva@pnl.gov OI Jiang, Weilin/0000-0001-8302-8313 NR 15 TC 7 Z9 7 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X EI 1872-9584 J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAR PY 2000 VL 161 BP 510 EP 514 DI 10.1016/S0168-583X(99)00701-6 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 299NE UT WOS:000086204100095 ER PT J AU Thevuthasan, S Jiang, W Young, JS Weber, WJ AF Thevuthasan, S Jiang, W Young, JS Weber, WJ TI Investigation of thermal recovery behavior in hydrogen-implanted SrTiO3 using high energy ion beam techniques SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 14th International Conference on Ion Beam Analysis/6th European Conference on Accelerators in Applied Research and Technology CY JUL 26-30, 1999 CL DRESEDEN, GERMANY SP Res Ctr Rossendorf, Inst Ion Beam Phys & Mat Res DE ion scattering; Rutherford backscattering spectrometry (RBS); nuclear reaction analysis (NRA); radiation effects; damage accumulation; strontium titanate (SrTiO3); hydrogen ID EPITAXIAL RECRYSTALLIZATION; AMORPHIZED SRTIO3 AB Damage accumulation, recovery process, and the influence of hydrogen on the recovery process have been investigated in single crystal SrTiO3 irradiated with low-energy (40 keV) H+ using in-situ hydrogen nuclear reaction analysis (NRA) and Rutherford backscattering spectrometry/channeling (RBS/C) techniques. Samples were irradiated at a temperature of 120 It with ion fluences of 5.0 x 10(16) and 1.0 x 10(17) H+/cm(2). For annealing temperatures up to similar to 470 K, isochronal annealing results indicate increasing disorder on the Sr, Ti, and O sublattices with temperature in the vicinity of the implanted hydrogen for low fluences of 5.0 x 10(16) H+/cm(2). Annealing this sample above 570 K. resulted in the cleavage of the entire irradiated surface. On-the-other-hand, high-temperature isochronal annealing results for 1.0 x 10(17) H+/cm(2) fluence show an increase in the backscattering yield across the penetration depth of the implant hydrogen due to the formation of hydrogen blisters. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Thevuthasan, S (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999,MSIN K8-93, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 12 TC 7 Z9 7 U1 1 U2 9 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 MAR PY 2000 VL 161 BP 544 EP 548 DI 10.1016/S0168-583X(99)00841-1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 299NE UT WOS:000086204100102 ER PT J AU Walsh, DS Doyle, BL AF Walsh, DS Doyle, BL TI Simultaneous nuclear reaction analyses of boron and phosphorus in thin borophosphosilicate glass films using (alpha, p) reactions SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 14th International Conference on Ion Beam Analysis/6th European Conference on Accelerators in Applied Research and Technology CY JUL 26-30, 1999 CL DRESEDEN, GERMANY SP Res Ctr Rossendorf, Inst Ion Beam Phys & Mat Res DE nuclear reaction analysis; (alpha, p); borophosphosilicate glass AB A method combining (alpha, p) nuclear reaction analysis (NRA) and ellipsometry has been developed for measuring the boron and phosphorus content of borophosphosilicate glass (BPSG) used for interlevel dielectrics in integrated circuits. Yields from the P-31(alpha, p(0))S-34 (Q = 0.63 MeV) and B-10(alpha, p(0))C-13 (Q = 4.06 MeV) reactions are coupled with ellipsometry thickness measurements to determine the average atomic percent of B and P in the film. We have determined that 6.0 MeV incident alpha's with a detector angle of 135 degrees and about 100 mu m of Mylar range foil are optimum for our system. The yield for the B-10(alpha, p(0))C-13 reaction is quite constant in our energy range of interest (similar to 5.8-6 MeV) but the yield for the P-31(alpha,p(0))S-34 is not. Consequently, a simple conversion from "standard" BPSG reference samples (independently quantified by ICP mass spectrometry) is adequate to calculate a film's %B content. The %P calculation is more complex, involving a three-dimensional fit of the P yield data and measured film thickness to the him %P content. This fit is based upon yield data from a matrix of standard film samples. The technique is sensitive to 0.1% with an accuracy of +/-10% depending on the sample. This measurement method is now used routinely at Sandia National Laboratories in support of our fabrication process lines. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Walsh, DS (reprint author), Sandia Natl Labs, POB 5800,MS 1056, Albuquerque, NM 87185 USA. NR 10 TC 6 Z9 7 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAR PY 2000 VL 161 BP 629 EP 634 DI 10.1016/S0168-583X(99)00981-7 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 299NE UT WOS:000086204100119 ER PT J AU Glover, CJ Ridgway, MC Byrne, AP Yu, KM Foran, GJ Clerc, C Hansen, JL Larsen, AN AF Glover, CJ Ridgway, MC Byrne, AP Yu, KM Foran, GJ Clerc, C Hansen, JL Larsen, AN TI Micro- and macro-structure of implantation-induced disorder in Ge SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 14th International Conference on Ion Beam Analysis/6th European Conference on Accelerators in Applied Research and Technology CY JUL 26-30, 1999 CL DRESDEN, GERMANY SP Res Ctr Rossendorf, Inst Ion Beam Phys & Mat Res DE Ge; extended X-ray absorption fine structure spectroscopy; perturbed angular correlation; ion implantation; defect characterisation; Rutherford backscattering spectrometry ID AMORPHOUS-GERMANIUM AB The structure of ion implantation-induced damage in Ge substrates has been investigated with a combination of ion-and photon-based techniques including Rutherford backscattering spectrometry (RBS), perturbed angular correlation (PAC) and extended X-ray absorption fine structure (EXAFS) spectroscopy. For MeV Ge ion implantation at -196 degrees C, the dose dependence of the decrease in local atomic order, determined from EXAFS and PAC, was compared to the number of displaced atoms determined from RES measurements. An EXAFS determined damage fraction was shown to be a better estimate of amorphous fraction than the number of displaced atoms. PAC was used to elucidate the evolution of defective configurations, and was compared to the RES and EXAFS results. A fit to the Overlap model with the overlap of two ion cascades for complete amorphization best described the experimental results. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Australian Natl Univ, Res Sch Phys Sci & Engn, Canberra, ACT, Australia. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. Aarhus Univ, Inst Phys & Astron, DK-8000 Aarhus, Denmark. RP Glover, CJ (reprint author), Australian Natl Univ, Res Sch Phys Sci & Engn, GPO Box 4, Canberra, ACT, Australia. EM chris.glover@anu.edu.au RI Yu, Kin Man/J-1399-2012; Ridgway, Mark/D-9626-2011; OI Yu, Kin Man/0000-0003-1350-9642; Ridgway, Mark/0000-0002-0642-0108; Byrne, Aidan/0000-0002-7096-6455 NR 16 TC 8 Z9 8 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAR PY 2000 VL 161 BP 1033 EP 1037 DI 10.1016/S0168-583X(99)00887-3 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 299NE UT WOS:000086204100195 ER PT J AU Berger, EL Klasen, M AF Berger, EL Klasen, M TI Low mass lepton pair production in hadron collisions SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT International Conference on the Structure and Interactions of the Photon (PHOTON 99)/12th International Workshop on Photon-Photon Collisions CY MAY 23-27, 1999 CL FREIBURG, GERMANY SP Deutsch Forsch Germeinsch, Deutsch Elektronen Synchrotron ID TO-LEADING ORDER; PARTON DISTRIBUTIONS; GLOBAL ANALYSIS; QCD AB The hadroproduction of lepton pairs with mass & and transverse momentum Q(T) can be described in perturbative QCD by the same partonic subprocesses as prompt photon production. We demonstrate that, like prompt photon production, lepton pair production is dominated by quark-gluon scattering in the region Q(T) > Q/2. This leads to sensitivity to the gluon density in kinematical regimes that are accessible both at collider and fixed target experiments while eliminating the theoretical and experimental uncertainties present in prompt photon production. C1 Argonne Natl Lab, HEP Theory Grp, Argonne, IL 60439 USA. RP Berger, EL (reprint author), Argonne Natl Lab, HEP Theory Grp, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 15 TC 4 Z9 4 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 MAR PY 2000 VL 82 BP 179 EP 184 DI 10.1016/S0920-5632(00)00151-1 PG 6 WC Physics, Particles & Fields SC Physics GA 308HD UT WOS:000086703700029 ER PT J AU Lathrop, KD AF Lathrop, KD TI A comparison of angular difference schemes for one-dimensional spherical geometry S-N equations SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article AB To investigate errors caused by angular differencing in approximating the streaming terms of the transport equation, five different approximations are evaluated for three test problems in one-dimensional spherical geometry. The following schemes are compared: diamond, special truncation error minimizing weighted diamond, linear continuous (the original SN scheme), linear discontinuous, and new quadratic continuous. To isolate errors caused by angular differencing, the approximations are derived from the transport equation without spatial differencing, and the resulting coupled ordinary differential equations (ODEs) are solved with art ODE solver. Results from the approximations are compared with analytic solutions derived for two-region purely absorbing spheres. Most of the approximations are derived by taking moments of the conservation form of the transport equation. The quadratic continuous approximation is derived taking the zeroth moment of both the transport equation and the first angular derivative of the transport equation. The advantages of this approach are described. In all of the approximations, the desirability is shown of using all initializing computation of the mu = -1 angular flux to correctly compute the central flux and of having a difference approximation that ensures this central flux is the same for all directions. The behavior of the standard discrete ordinates equations in the diffusion limit is reviewed, and the linear and quadratic continuous approximations are shown to have the correct diffusion limit if an equal interval discrete quadrature is used. In all three test problems, the weighted diamond difference approximation has smaller maximum and average relative flux errors than the diamond or the linear continuous difference approximations. The quadratic continuous approximation and the linear discontinuous approximation are both more accurate than the other approximations, and the quadratic continuous approximation has a decided edge over the linear discontinuous approximation in relative flux errors. The diamond, weighted diamond, and linear continuous approximations show quadratic system absorption and system leakage error reduction behavior with increasing N. The linear discontinuous and quadratic continuous approximations show fourth-order error reduction in these quantities. In one of the two-region test problems, the slope of the exact angular flux changes from nearly vertical to nearly horizontal at those points in the exterior region at which the interior region source just becomes visible. At these spatial points, errors in the continuous approximations propagate to each successive outgoing direction, leading to an oscillatory spatial error. The discontinuous approximation does not propagate these errors, although errors near the point of rapid slope change are larger than in the quadratic continuous approximation. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Lathrop, KD (reprint author), Stanford Linear Accelerator Ctr, POB 4349, Stanford, CA 94309 USA. NR 11 TC 16 Z9 18 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD MAR PY 2000 VL 134 IS 3 BP 239 EP 264 PG 26 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 287ME UT WOS:000085509000001 ER PT J AU Chang, GS Ryskamp, JM AF Chang, GS Ryskamp, JM TI Depletion analysis of mixed-oxide fuel pins in light water reactors and the advanced test reactor SO NUCLEAR TECHNOLOGY LA English DT Article AB An experiment containing weapons-grade mixed-oxide (WG-MOX) fuel has been designed and is being irradiated in the Advanced Test Reactor (ATR) at the Idaho National Engineering and Environmental Laboratory (INEEL). The ability to accurately predict fuel pin performance is an essential requirement for the MOX fuel test assembly design, Detailed radial fission power and temperature profile effects and fission gas release in the fuel pin are a function of the fuel pin's temperature, fission power, and fission product and actinide concentration profiles. In addition, the burnup-dependent profile analyses in irradiated fuel pins is important for fuel performance analysis to support the potential licensing of the MOX fuel made from WG-plutonium and depleted uranium for use in U.S. reactors. The MCNP Coupling With ORIGEN2 burnup calculation code (MCWO) can analyze the detailed burnup profiles of WG-MOX and reactor-grade mixed-oxide (RG-MOX) fuel pins. The validated code MCWO can provide the best-estimate neutronic characteristics of fuel burnup performance analysis. Applying this capability with a new minicell method allows calculation of detailed nuclide concentration and power distributions within the MOX pins as a function of burnup. This methodology was applied to MOX fuel in a commercial pressurized water reactor and in an experiment currently being irradiated in the ATR. The prediction of nuclide concentration profiles and power distributions in irradiated MOX pins via this new methodology can provide insights into MOX fuel performance. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Chang, GS (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 23 TC 15 Z9 15 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 MAR PY 2000 VL 129 IS 3 BP 326 EP 337 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 283XP UT WOS:000085301600003 ER PT J AU Blanchat, TK Malliakos, AC AF Blanchat, TK Malliakos, AC TI Testing a passive autocatalytic recombiner in the Surtsey facility SO NUCLEAR TECHNOLOGY LA English DT Article AB Performance tests of a scaled passive autocatalytic recombiner (PAR) were performed in the Surtsey test vessel at Sandia National Laboratories. Measured hydrogen depletion rate data ware obtained and compared with previous work. Depletion rate is most likely proportional to PAR scale. PAR performance in steamy environments (with and without hydrophobic coating) was investigated. The rests determined that the PAR startup delay times decrease with increasing hydrogen concentrations in steamy environments. Tests with placement of the PAR near a wall (as opposed to a center location) yielded reduced depletion rates. Tests at low oxygen concentrations also showed a reduced recombination rate. The PAR repeatedly ignited hydrogen at similar to 6 mol% concentration with a catalyst temperature near 940 K. Velocity data at the PAR exhaust were used to calculate the volumetric flow rare through the PAR as a function of the vessel hydrogen concentration. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. US Nucl Regulatory Commiss, Washington, DC 20555 USA. RP Blanchat, TK (reprint author), Sandia Natl Labs, POB 5800,Mail Stop 1139, Albuquerque, NM 87185 USA. NR 10 TC 4 Z9 4 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD MAR PY 2000 VL 129 IS 3 BP 356 EP 373 PG 18 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 283XP UT WOS:000085301600005 ER PT J AU Li, WH Hesabi, B Babbo, A Pacione, C Liu, JM Chen, DJ Nickoloff, JA Shen, ZY AF Li, WH Hesabi, B Babbo, A Pacione, C Liu, JM Chen, DJ Nickoloff, JA Shen, ZY TI Regulation of double-strand break-induced mammalian homologous recombination by UBL1, a RAD51-interacting protein SO NUCLEIC ACIDS RESEARCH LA English DT Article ID UBIQUITIN-LIKE PROTEIN; GTPASE-ACTIVATING PROTEIN; NUCLEAR-PORE COMPLEX; DOT-ASSOCIATED PROTEINS; CROSS-LINKING AGENTS; YEAST RAD52 PROTEIN; REPAIR GENE RAD23; SACCHAROMYCES-CEREVISIAE; DNA-REPAIR; IONIZING-RADIATION AB Mammalian RAD51 protein plays essential roles in DNA homologous recombination, DNA repair and cell proliferation. RAD51 activities are regulated by its associated proteins, It was previously reported that a ubiquitin-like protein, UBL1, associates with RAD51 in the yeast two-hybrid system. One function of UBL1 is to covalently conjugate with target proteins and thus modify their function. In the present study we found that non-conjugated UBL1 forms a complex with RAD51 and RAD52 proteins in human cells. Overexpression of UBL1 down-regulates DNA double-strand break-induced homologous recombination in CHO cells and reduces cellular resistance to ionizing radiation in HT1080 cells. With or without overexpressed UBL1, most homologous recombination products arise by gene conversion. However, overexpression of UBL1 reduces the fraction of bidirectional gene conversion tracts. Overexpression of a mutant UBL1 that is incapable of being conjugated retains the ability to inhibit homologous recombination. These results suggest a regulatory role for UBL1 in homologous recombination. C1 Univ Illinois, Coll Med, Dept Mol Genet MC669, Chicago, IL 60607 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ New Mexico, Sch Med, Dept Mol Genet & Microbiol, Albuquerque, NM 87131 USA. RP Shen, ZY (reprint author), Univ Illinois, Coll Med, Dept Mol Genet MC669, 900 S Ashland Ave, Chicago, IL 60607 USA. FU NCI NIH HHS [CA77693, R01 CA077693, R37 CA050519, R01 CA050519, CA54079]; NIEHS NIH HHS [R29 ES008353, R01 ES008353, ES08353] NR 90 TC 57 Z9 57 U1 2 U2 3 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD MAR 1 PY 2000 VL 28 IS 5 BP 1145 EP 1153 DI 10.1093/nar/28.5.1145 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 289YA UT WOS:000085648500015 PM 10666456 ER PT J AU Stomakhin, AA Vasiliskov, VA Timofeev, E Schulga, D Cotter, RJ Mirzabekov, AD AF Stomakhin, AA Vasiliskov, VA Timofeev, E Schulga, D Cotter, RJ Mirzabekov, AD TI DNA sequence analysis by hybridization with oligonucleotide microchips: MALDI mass spectrometry identification of 5mers contiguously stacked to microchip oligonucleotides SO NUCLEIC ACIDS RESEARCH LA English DT Article ID GENETIC INFORMATION; ARRAYS; LIGATION AB Matrix-assisted laser desorption ionization mass spectrometry (MALDI MS) has been applied to increase the informational output from DNA sequence analysis. It has been used to analyze DNA by hybridization with microarrays of gel-immobilized oligonucleotides extended with stacked 5mers. In model experiments, a 28 nt long DNA fragment was hybridized with 10 immobilized, overlapping 8mers. Then, in a second round of hybridization DNA-8mer duplexes were hybridized with a mixture of 10 5mers. The stability of the 5mer complex with DNA was increased to raise the melting temperature of the duplex by 10-15 degrees C as a result of stacking interaction with 8mers. Contiguous 13 bp duplexes containing an internal break were formed. MALDI MS identified one or, in some cases, two 5mers contiguously stacked to each DNA-8mer duplex formed on the microchip. Incorporating a mass label into 5mers optimized MALDI MS monitoring. This procedure enabled us to reconstitute the sequence of a model DNA fragment and identify polymorphic nucleotides. The application of MALDI MS identification of contiguously stacked 5mers to increase the length of DNA for sequence analysis is discussed. C1 Argonne Natl Lab, Biochip Technol Ctr, Argonne, IL 60439 USA. Russian Acad Sci, Engelhard Inst Mol Biol, Moscow 117984, Russia. Moscow Inst Phys & Technol, Dolgoprudnyi 141700, Russia. Johns Hopkins Univ, Sch Med, Dept Pharmacol & Mol Sci, Middle Atlantic Mass Spectrometry Lab, Baltimore, MD 21205 USA. RP Mirzabekov, AD (reprint author), Argonne Natl Lab, Biochip Technol Ctr, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 24 TC 30 Z9 33 U1 0 U2 3 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD MAR 1 PY 2000 VL 28 IS 5 BP 1193 EP 1198 DI 10.1093/nar/28.5.1193 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 289YA UT WOS:000085648500021 PM 10666462 ER PT J AU Phuoc, TX AF Phuoc, TX TI Laser spark ignition: experimental determination of laser-induced breakdown thresholds of combustion gases SO OPTICS COMMUNICATIONS LA English DT Article DE laser ignition; breakdown threshold ID MIXTURES; FLAME AB This short paper reports preliminary results on experimental measurements of breakdown threshold laser intensities of air, O-2,O- N-2, H-2, and CH4 using a Q-switched Nd-Yag laser operating at 532 nm and 1064 nm and 5.5 ns pulse. The breakdown threshold intensities were measured for the range of pressure from 150 to about 3040 Torr. The results showed that the pressure dependence of breakdown threshold is I-thr proportional to p(-n) which is in agreement with the inverse bremsstrahlung absorption process creating breakdown, The degree by which I-thr depends on pressure was found to be stronger at 532 nm than at 1064 nm indicating the important effect of diffusion loss. Published by Elsevier Science B.V. C1 Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. RP Phuoc, TX (reprint author), Fed Energy Technol Ctr, POB 10940,MS 84-340, Pittsburgh, PA 15236 USA. NR 13 TC 114 Z9 114 U1 2 U2 22 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD MAR 1 PY 2000 VL 175 IS 4-6 BP 419 EP 423 DI 10.1016/S0030-4018(00)00488-0 PG 5 WC Optics SC Optics GA 292AU UT WOS:000085772600021 ER PT J AU Li, YL Schillinger, H Ziener, C Sauerbrey, R AF Li, YL Schillinger, H Ziener, C Sauerbrey, R TI Reinvestigation of the Duguay soft X-ray laser: a new parameter space for high power femtosecond laser pumped systems (vol 144, pg 118, 1997) SO OPTICS COMMUNICATIONS LA English DT Correction C1 Univ Jena, Inst Opt & Quantenelekt, D-07743 Jena, Germany. RP Li, YL (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD MAR 1 PY 2000 VL 175 IS 4-6 BP 477 EP 477 PG 1 WC Optics SC Optics GA 292AU UT WOS:000085772600027 ER PT J AU Gorbarenko, SA Southon, JR AF Gorbarenko, SA Southon, JR TI Detailed Japan Sea paleoceanography during the last 25 kyr: Constraints from AMS dating and delta O-18 of planktonic foraminifera SO PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY LA English DT Article DE Japan Sea; sea level; surface water salinity; water exchange ID YOUNGER DRYAS EVENT; NORTHWESTERN PACIFIC; OXYGEN ISOTOPES; STABLE-ISOTOPE; RED-SEA; LEVEL; RECORD; ICE; HOLOCENE; CLIMATE AB We have reconstructed paleoceanographic changes in the Japan Sea for the period from the Last Glacial Maximum (LGM) to the present, using expanded paleoclimate proxy records from two cores, together with previously published results from three others. A suite of new Accelerated Mass Spectrometer (AMS) C-14 dates provides chronologies that differ from earlier age models and suggest correlation between conditions in the Japan Sea, changes in the North Pacific, and global sea level and climate changes. We present evidence that reduced salinity of the Japan Sea surface water during the late Pleistocene was due primarily to the increased importance of the precipitation-evaporation balance at a time when lowered sea level had reduced water exchange with the Pacific to a few percent of the present value. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific Oceanol Inst, Vladivostok 690041, Russia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Gorbarenko, SA (reprint author), Pacific Oceanol Inst, Baltiyskaya 43, Vladivostok 690041, Russia. NR 53 TC 78 Z9 91 U1 1 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0031-0182 J9 PALAEOGEOGR PALAEOCL JI Paleogeogr. Paleoclimatol. Paleoecol. PD MAR 1 PY 2000 VL 156 IS 3-4 BP 177 EP 193 DI 10.1016/S0031-0182(99)00137-6 PG 17 WC Geography, Physical; Geosciences, Multidisciplinary; Paleontology SC Physical Geography; Geology; Paleontology GA 289KR UT WOS:000085620300001 ER PT J AU Waldemark, K Lindblad, T Becanovic, V Guillen, JLL Klingner, PL AF Waldemark, K Lindblad, T Becanovic, V Guillen, JLL Klingner, PL TI Patterns from the sky - Satellite image analysis using pulse coupled neural networks for pre-processing, segmentation and edge detection SO PATTERN RECOGNITION LETTERS LA English DT Article DE satellite images; segmentation; artefacts; textures; PCNN; FORTE AB In this work we attempt to distinguish land from water in satellite images, specifically images taken by the FORTE satellite. First, we successfully approximate areas hidden by stationary artefacts in the image. We then segment regions of land from water. Finally, we determine the boundaries of the surrounding landmasses. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Royal Inst Technol, Dept Phys, SE-10405 Stockholm, Sweden. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Lindblad, T (reprint author), Royal Inst Technol, Dept Phys, Frascativagen 24, SE-10405 Stockholm, Sweden. NR 32 TC 25 Z9 27 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8655 J9 PATTERN RECOGN LETT JI Pattern Recognit. Lett. PD MAR PY 2000 VL 21 IS 3 BP 227 EP 237 DI 10.1016/S0167-8655(99)00152-X PG 11 WC Computer Science, Artificial Intelligence SC Computer Science GA 293PY UT WOS:000085862900004 ER PT J AU Somogyi, G Jenei, E Szokol, J Buris, L Busis, L Nagy, D Pap, L AF Somogyi, G Jenei, E Szokol, J Buris, L Busis, L Nagy, D Pap, L TI Distribution of inorganic elements in human autopsy tissue SO PHARMAZIE LA English DT Article; Proceedings Paper CT 2nd Conference on Retrometabolism Based Drug Design and Targeting CY MAY 11-14, 1999 CL AMELIA ISL, FL ID ACUTE MYOCARDIAL-INFARCTION; HUMAN-HEART MUSCLE; TRACE-ELEMENTS; MAGNESIUM; IRON; POTASSIUM; DISEASE; CALCIUM; SAMPLES; DEATH AB In the practice of forensic medicine, we find many of cases of death when the actual cause is not determinable with autopsy, histological or toxicological examinations. In these cases of death, we can consider cardiac dysfunction of unknown origin, in the background of which such a physiologic cardiac insufficiency occurs that cannot be detected with the previously mentioned methods. The dysfunction is possibly associated with a significant change in certain inorganic elements, primarily in the conduction system of the heart. In the absence of published data, our goal was to determine the concentration of inorganic elements in the specialized rhythm determining muscle cell groups in the heart: sinus node (SN), atrioventricular node (AV), septum (SE), left ventricle anterior wall (LVAW). With microwave technology we destroyed the muscle tissue and measured the concentration of ions (Na, Mg, K, Ca, Mn, Fe, Cu, Zn, P, S) using inductive Completed Plasma Atom Emission Spectrometry (ICP-AES) equipment. Of the 24 cases examined, the average ion concentrations in mu g/g were the following; Sinus: Na 2602 +/- 493, Mg 120 +/- 24, K 1787 +/- 347, Ca 244 +/- 41,Mn 0.129 +/- 0.011, Fe 58 +/- 12, Cu 2.171 +/- 0.46, Zn 10.4 +/- 2.027. P 1147 +/- 227, S 2301 +/- 245; Septum: Na 1452 +/- 315, Mg 243 +/- 56, K 3269 +/- 689, Ca 105 +/- 26, Mn 0.17 +/- 0.05, Fe 74 +/- 16, Cu 3.557 +/- 0.952, Zn 25.75 +/- 8.4, P 2764 +/- 494, S 3001 +/- 523; Av: Na 2614 +/- 517, Mg 242 +/- 40.2, K 2010 +/- 395, Ca 271 +/- 27.3, Mn 0.13 +/- 0.029, Fe 54 +/- 12, Cu 2.369 +/- 0.297, Zn 15 +/- 3.2, P 1625 +/- 291, S 2535 +/- 346; Lvaw: Na 1340 +/- 201. Mg 250 +/- 37, K 3659 +/- 532, Ca 88 +/- 22, Mn 0.175 +/- 0.05, Fe 76 +/- 19, Cu 3.62 +/- 0.58, Zn 27.13 +/- 3.1, P 3025 +/- 441 S 3140 +/- 440. C1 Univ Debrecen, Sch Med, Inst Forens Med, H-4012 Debrecen, Hungary. Univ Debrecen, Dept Surg 2, H-4012 Debrecen, Hungary. Univ Calif Berkeley, Ctr Funct Imaging, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Debrecen, Inst Inorgan Chem, Debrecen, Hungary. RP Somogyi, G (reprint author), Univ Debrecen, Sch Med, Inst Forens Med, Nagyerdei Krt 98, H-4012 Debrecen, Hungary. EM gsomogyi@jaguar.dote.hu NR 24 TC 4 Z9 4 U1 0 U2 3 PU GOVI-VERLAG PHARMAZEUTISCHER VERLAG GMBH PI ESCHBORN PA PHARMAZEUTISCCARL MANNICH STR 26, D-65760 ESCHBORN, GERMANY SN 0031-7144 J9 PHARMAZIE JI Pharmazie PD MAR PY 2000 VL 55 IS 3 BP 239 EP 242 PG 4 WC Chemistry, Medicinal; Chemistry, Multidisciplinary; Pharmacology & Pharmacy SC Pharmacology & Pharmacy; Chemistry GA 305LH UT WOS:000086541200015 PM 10756547 ER PT J AU Lebedev, OI Van Tendeloo, G Amelinckx, S Ju, HL Krishnan, KM AF Lebedev, OI Van Tendeloo, G Amelinckx, S Ju, HL Krishnan, KM TI High-resolution electron microscopy study of strained epitaxial La0.7Sr0.3MnO3 thin films SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article AB The microstructure of strained epitaxial La0.7Sr0.3MnO3 (LSMO) films on a LaAlO3 (001) substrate has been investigated by means of electron diffraction and high-resolution electron microscopy in cross-section and plan view. Fourier transforms of the high-resolution images allow us to deduce the local lattice parameters at increasing distance from the interface. The evolution of stress in the film is studied as a function of film thickness and thermal treatment. It is found that, close to the interface, both the film and the substrate are elastically strained in the opposite sense such that the interface is perfectly coherent for thin films not exceeding a certain thickness (about 30-35nm). In thicker films, inhomogeneities develop in the as-grown films. In thicker (about 120nm) films the stress is partially relieved after annealing by the formation of misfit dislocations with an edge character. In annealed thick films we also provide some evidence for the formation of coherent 'precipitates' that contribute to the relief of stress. It is suggested that part of the mismatch strain is accommodated by the isomorphous substitution of ions of a different size and/or a different charge. C1 Univ Ctr Antwerpen, EMAT, B-2020 Antwerp, Belgium. Univ Calif Berkeley, Div Mat Sci, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Lebedev, OI (reprint author), Univ Ctr Antwerpen, EMAT, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. RI Lebedev, Oleg/B-4443-2014 NR 12 TC 53 Z9 53 U1 4 U2 24 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAR PY 2000 VL 80 IS 3 BP 673 EP 691 PG 19 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 293VF UT WOS:000085873500011 ER PT J AU Heggen, M Feuerbacher, M Schall, P Klein, H Fisher, IR Canfield, PC Urban, K AF Heggen, M Feuerbacher, M Schall, P Klein, H Fisher, IR Canfield, PC Urban, K TI Plastic deformation of icosahedral Zn-Mg-Dy single quasicrystals SO PHILOSOPHICAL MAGAZINE LETTERS LA English DT Article ID QUASI-CRYSTALS; GROWTH AB Plastic deformation experiments have been performed on Zn-Mg-Dy icosahedral single quasicrystals at temperatures between 490 and 530 degrees C and at strain rates of 10(-5) and 10(-6) s(-1). The stress-strain curves show strong yielding followed by a steady-state regime with a constant flow stress level up to strains of about 8%. Thermodynamic activation parameters of the deformation process were determined and are discussed in comparison with those found for icosahedral Al-Pd-Mn. Microstructural investigations by transmission electron microscopy on deformed samples were performed and indicate a deformation mechanism mediated by dislocations. C1 Forschungszentrum Julich, Inst Festkorperforsch, D-52425 Julich, Germany. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Heggen, M (reprint author), Forschungszentrum Julich, Inst Festkorperforsch, Postfach 1913, D-52425 Julich, Germany. EM m.feuerbacher@fz-juelich.de RI Feuerbacher, Michael/K-3768-2013; Heggen, Marc/K-5099-2013; Canfield, Paul/H-2698-2014 OI Feuerbacher, Michael/0000-0003-2882-4960; Heggen, Marc/0000-0002-2646-0078; NR 19 TC 14 Z9 15 U1 3 U2 7 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0950-0839 J9 PHIL MAG LETT JI Philos. Mag. Lett. PD MAR PY 2000 VL 80 IS 3 BP 129 EP 136 DI 10.1080/095008300176254 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 298KV UT WOS:000086139000001 ER PT J AU Garrett, AJ Irvine, JM King, AD Evers, TK Levine, DA Ford, C Smyre, JL AF Garrett, AJ Irvine, JM King, AD Evers, TK Levine, DA Ford, C Smyre, JL TI Application of multispectral imagery to assessment of a hydrodynamic simulation of an effluent stream entering the Clinch River SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article ID SUSPENDED SEDIMENT; GROWTH AB This study investigates the feasibility of using remote sensing systems to estimate and model contaminant transport at known hazardous waste sites. We used airborne (Daedalus) imagery and 3D hydrodynamic simulations to estimate the pow rate of Popular Creek as it enters the Clinch River, located on the U.S. Department of Energy (DOE) Oak Ridge Reservation (ORR) in Tennessee. The collection of ground-truth data and the simulations were complicated by the variability of the Clinch River flow, which we attempted to reproduce in the simulations. Comparisons of the Daedalus imagery to images created from the simulations led to the conclusion that the Clinch River/ Poplar Creek system shifts back and forth between three distinct pow regimes that have different pollutant transport patterns. Results of this research suggest that remote-sensing delta combined with high-resolution numerical modeling and limited surface measurements might be able to define pollutant transport in large bodies of water as well as methods that rely only on more extensive surface measurements. C1 Westinghouse Savannah River Co, Rivers Technol Ctr, Aiken, SC 29808 USA. Sci Applicat Int Corp, Arlington, VA USA. Oak Ridge Natl Lab, Lockheed Martin Energy Res Corp, Oak Ridge, TN 37831 USA. RP Garrett, AJ (reprint author), Westinghouse Savannah River Co, Rivers Technol Ctr, Bldg 773-A,Off A-1000, Aiken, SC 29808 USA. NR 12 TC 9 Z9 9 U1 0 U2 0 PU AMER SOC PHOTOGRAMMETRY PI BETHESDA PA 5410 GROSVENOR LANE SUITE 210, BETHESDA, MD 20814-2160 USA SN 0099-1112 J9 PHOTOGRAMM ENG REM S JI Photogramm. Eng. Remote Sens. PD MAR PY 2000 VL 66 IS 3 BP 329 EP 335 PG 7 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA 290FQ UT WOS:000085666000009 ER PT J AU Mezei, F AF Mezei, F TI A pilgrim's progress SO PHYSICA B LA English DT Editorial Material C1 Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Mezei, F (reprint author), Hahn Meitner Inst Kernforsch Berlin GmbH, Glienickerstr 100, D-14109 Berlin, Germany. NR 0 TC 0 Z9 0 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 1 EP 5 DI 10.1016/S0921-4526(99)01352-6 PG 5 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000003 ER PT J AU Zsigmond, G Mezei, F AF Zsigmond, G Mezei, F TI Simulation of the time-of-flight-backscattering neutron spectrometer IRIS - The Monte Carlo data reduction technique SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE backscattering; time of fight; resolution function; Monte Carlo simulations AB It was demonstrated that it is possible to compute the resolution function of TRIS with high precision which is comparable to the raw data precision limits. The numerical calculations were performed by MC computer simulations by taking into account the very detailed spectrometer geometry and the exact material specifications of the instrument components. Precise vanadium data were used to fine-tune and bench mark the MC modelling of the spectrometer. Unlike the conventional methods of data analysis which perform convolution of the expected resolution and various model S(q, w)'s, here the numerical fitting method, MC data reduction (MCDR) was introduced on the LRIS, which is based on computer simulations of the measured spectra for models of the scattering function. The most probable values of the model parameters may thus be determined by the criterion of best agreement between measured and simulated spectra. With this method the counts which are experimentally observed in each single-detector channel were numerically computed and thus, as an example, a very detailed line-shape analysis of rotons in superfluid He-4 was made possible. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Zsigmond, G (reprint author), Hahn Meitner Inst Kernforsch Berlin GmbH, Glienicker Str 100, D-14109 Berlin, Germany. NR 2 TC 3 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 106 EP 107 DI 10.1016/S0921-4526(99)01267-3 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000037 ER PT J AU Mezei, F Russina, M Schorr, S AF Mezei, F Russina, M Schorr, S TI The multiwavelength cold neutron time-of-flight spectrometer project IN500 at LANSCE SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE neutron instruments; time of flight; pulsed neutrons AB The IN500 projects lakes advantage of three novel techniques to achieve a more than an order of magnitude gain in beam intensity delivered onto the sample at equal resolution compared to the best existing cold neutron TOF spectrometers: ta) the newly installed high intensity, long pulse coupled moderator at the Lujan center short pulse spallation source facility, (bl the recently proposed repetition rate multiplication trick to improve data collection efficiency and (c) the reduction of beam losses in long neutron guides by using a novel, "ballistic" design. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. RP Mezei, F (reprint author), Univ Calif Los Alamos Natl Lab, MS H805, Los Alamos, NM 87545 USA. RI Russina, Margarita/E-9886-2016 OI Russina, Margarita/0000-0003-2067-606X NR 2 TC 10 Z9 10 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 128 EP 129 DI 10.1016/S0921-4526(99)01377-0 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000048 ER PT J AU Lefmann, K Nielsen, K Tennant, A Lake, B AF Lefmann, K Nielsen, K Tennant, A Lake, B TI McStas 1.1: a tool for building neutron Monte Carlo simulations SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE Monte Carlo simulations; neutron instruments; resolution function ID TRIPLE-AXIS SPECTROMETER AB McStas is a project to develop general tools for the creation of simulations of neutron scattering experiments. In this paper, we briefly introduce McStas and describe a particular application of the program: the Monte Carlo calculation of the resolution function of a standard triple-axis neutron scattering instrument. The method compares well with the analytical calculations of Popovici. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Riso Natl Lab, Condensed Matter Phys & Chem Dept, DK-4000 Roskilde, Denmark. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Lefmann, K (reprint author), Riso Natl Lab, Condensed Matter Phys & Chem Dept, Frederiksborgvej 399, DK-4000 Roskilde, Denmark. RI Lefmann, Kim/M-9228-2014; Tennant, David/Q-2497-2015; OI Lefmann, Kim/0000-0003-4282-756X; Tennant, David/0000-0002-9575-3368; Lake, Bella/0000-0003-0034-0964 NR 6 TC 16 Z9 16 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 152 EP 153 DI 10.1016/S0921-4526(99)01409-X PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000060 ER PT J AU Pappas, C Kali, G Boni, P Kischnik, R Mertens, LA Granz, P Mezei, F AF Pappas, C Kali, G Boni, P Kischnik, R Mertens, LA Granz, P Mezei, F TI The novel multidetector neutron spin echo spectrometer SPAN at BENSC SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE neutron spin echo; neutron instruments; polarized neutrons; cold neutrons AB The peculiarity in the design of SPAN is in the NSE precession field, which is created by three pairs of coils with diameters 1, 3 and 4.8 mi respectively, and allows for simultaneous NSE measurements over a wide angular range. The experimental results confirmed the high axial symmetry of the precession field and show that the new magnetic field configuration of SPAN is particularly appropriate for multidetector NSE over a wide angular range. (C) 2000 Elsevier Science B.V. All rights reserved. C1 HMI Berlin, Hahn Meitner Inst, BENSC, D-14109 Berlin, Germany. ETH Zurich, Neutron Scattering Lab, CH-5232 Villigen, Switzerland. PSI, CH-5232 Villigen, Switzerland. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Pappas, C (reprint author), HMI Berlin, Hahn Meitner Inst, BENSC, Glienicker Str 100, D-14109 Berlin, Germany. RI Kali, Gyorgy/C-2070-2008 NR 3 TC 9 Z9 10 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 162 EP 163 DI 10.1016/S0921-4526(99)01300-9 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000065 ER PT J AU Schober, H Dianoux, AJ Cook, JC Mezei, F AF Schober, H Dianoux, AJ Cook, JC Mezei, F TI Upgrade of the INS cold neutron time-of-flight spectrometer SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE neutron instruments; time of flight AB We present the main design characteristics and give a concise performance evaluation of the new IN5 cold-neutron time-of-flight spectrometer at the ILL. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Inst Laue Langevin, F-38042 Grenoble, France. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Schober, H (reprint author), Inst Laue Langevin, BP 156, F-38042 Grenoble, France. NR 4 TC 4 Z9 4 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 164 EP 165 DI 10.1016/S0921-4526(99)01338-1 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000066 ER PT J AU Farhi, E Tagantsev, AK Hehlen, B Currat, R Boatner, LA Courtens, E AF Farhi, E Tagantsev, AK Hehlen, B Currat, R Boatner, LA Courtens, E TI The broad Brillouin doublets and central peak of KTaO3 SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE computer modelling; perovskite compounds; phonons; spectroscopy ID SRTIO3; 4-K AB The incipient ferroelectric KTaO3 presents low-T Brillouin spectra anomalies, e.g. a broad central peak (CP), and some additional Brillouin doublets (BD). whose origin are interpreted in terms of phonon-density fluctuation processes. A parameterisation from new extensive high-resolution neutron-scattering measurements is used to show that hydrodynamic second sound from high damping (compared to ED frequency). TA phonons may exist in the crystal. Furthermore, low damping thermal phonons may scatter light through two-phonon difference processes and appear on Brillouin spectra either as a sharp or a broader ED, depending on the phonon damping and group velocity The comparison between computed anisotropies and experimental measurements favours the second process. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Inst Max Von Laue Paul Langevin, F-38042 Grenoble 9, France. Univ Montpellier 2, Lab Verres, F-34095 Montpellier, France. Ecole Polytech Fed Lausanne, Lab Ceram, CH-1015 Lausanne, Switzerland. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Farhi, E (reprint author), Inst Max Von Laue Paul Langevin, BP 156, F-38042 Grenoble 9, France. RI Tagantsev, Alexander/E-3707-2010; Boatner, Lynn/I-6428-2013 OI Boatner, Lynn/0000-0002-0235-7594 NR 10 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 274 EP 275 DI 10.1016/S0921-4526(99)01482-9 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000116 ER PT J AU Fuhrmann, D Criswell, L Mo, H Volkmann, UG Herwig, KW Taub, H Hansen, FY AF Fuhrmann, D Criswell, L Mo, H Volkmann, UG Herwig, KW Taub, H Hansen, FY TI Diffusive motion in model soft matter systems: quasielastic neutron scattering study of short- and intermediate-length alkane layers SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE diffusion; quasielastic scattering; alkane layers ID GRAPHITE; BUTANE AB Among organic-chain molecules, normal alkanes [CH3(CH2)(n-2)CH3; n < 40] provide model systems in which to study the effect of molecular flexibility on diffusion in adsorbed films. Here we give an overview of our quasielastic neutron scattering studies of alkane films adsorbed on a graphite substrate, emphasizing the dependence of the observed spectra on the molecular length. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Univ Missouri, Res Reactor Facil, Columbia, MO 65211 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Pontificia Univ Catolica Chile, Fac Fis, Santiago 22, Chile. Tech Univ Denmark, Dept Chem, DK-2800 Lyngby, Denmark. RP Taub, H (reprint author), Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. RI Herwig, Kenneth/F-4787-2011; Volkmann, Ulrich/H-1802-2014 NR 7 TC 10 Z9 10 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 345 EP 346 DI 10.1016/S0921-4526(99)01550-1 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000148 ER PT J AU Russina, M Mezei, F AF Russina, M Mezei, F TI Intermediate range order dynamics - key to understanding of the glass transition SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE glass transitions; relaxation phenomena; mode coupling; quasielastic scattering AB Introducing a new experimental approach allowed us to extend the study of the collective dynamics to the length scale of intermediate range order in the model glass former Ca-K-NO3 (CKN) using time-of-flight (NEAT/BENSC) and spin-echo (InLL/lLL) technique. Our results provide for the first time direct experimental evidence that the beta-process is of relaxational nature and corresponds to fast heterogeneous flow of groups of atoms. We did not observe any sign of the sharp singularity of the effective Debye-Waller factor, which could be an indication of the mode coupling theory critical temperature (Gotze, Z. Phys, 60 (1985) 195; Gotze and Sjogren, Rep. Progr. Phys. 55 (1992) 242). (C) 2000 Elsevier Science B.V, All rights reserved. C1 Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Russina, M (reprint author), Hahn Meitner Inst Kernforsch Berlin GmbH, Glienicker Str 100, D-14109 Berlin, Germany. NR 8 TC 1 Z9 1 U1 4 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 437 EP 439 DI 10.1016/S0921-4526(99)01654-3 PG 3 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000193 ER PT J AU Rehm, C Fritzsche, H Maletta, H Klose, F AF Rehm, C Fritzsche, H Maletta, H Klose, F TI Modification of structural properties of Nb/Fe(110) multilayers via hydrogen absorption SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE reflectometry; hydrogen; thin films ID FILMS AB We report on the structural effect of hydrogen loading from the gas phase on Nb/Fe multilayers (t(Nb) = 10-1000 Angstrom). The equilibrium hydrogen concentration in the Nb layers and the hydrogen-induced layer thickness expansion perpendicular to the him plane were determined as function of external hydrogen pressure by means of in situ neutron reflectivity measurements. In situ X-ray diffraction experiments performed on the same samples yielded the corresponding expansion of the out-of-plane Nb(1 1 0) interplanar spacing. It was found in all samples that the relative expansion of the Nb layers is considerably larger than the relative increase of the Nb(1 1 0) interplanar spacing, indicating a second absorption mechanism aside from the well-known incorporation of hydrogen at interstitial sites of the host metal. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. RP Maletta, H (reprint author), Hahn Meitner Inst Kernforsch Berlin GmbH, Glienicker Str 100, D-14109 Berlin, Germany. OI Fritzsche, Helmut/0000-0001-5288-8302 NR 4 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 549 EP 550 DI 10.1016/S0921-4526(99)01403-9 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000244 ER PT J AU Radaelli, PG Ibberson, RM Cheong, SW Mitchell, JF AF Radaelli, PG Ibberson, RM Cheong, SW Mitchell, JF TI Neutron scattering studies of phase segregation in Pr0.7Ca0.3MnO3 SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE neutron scattering; phase segregation AB By using high-resolution time-of-flight neutron powder diffraction, we have investigated phase segregation in the narrow-bandwidth manganite Pr0.7Ca0.3MnO3. Unexpectedly, our data clearly demonstrate that phase segregation in Pr0.7Ca0.3MnO3 is unrelated to electronic phase segregation, but is primarily driven by chemical disorder and intra-granular strains, similar to martensitic phase transitions. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08855 USA. Argonne Natl Lab, MSD, Argonne, IL 60439 USA. RP Radaelli, PG (reprint author), Rutherford Appleton Lab, ISIS Facil, Chilton, Didcot OX11 0QX, Oxon, England. RI Radaelli, Paolo/C-2952-2011; Ibberson, Richard/P-8397-2015 OI Radaelli, Paolo/0000-0002-6717-035X; Ibberson, Richard/0000-0003-0007-706X NR 4 TC 14 Z9 14 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 551 EP 553 DI 10.1016/S0921-4526(99)01740-8 PG 3 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000245 ER PT J AU Coldea, R Hayden, SM Aeppli, G Perring, TG Frost, CD Mason, TE Cheong, SW Fisk, Z AF Coldea, R Hayden, SM Aeppli, G Perring, TG Frost, CD Mason, TE Cheong, SW Fisk, Z TI Spin excitations and exchange couplings in the cuprate antiferromagnet La2CuO4 SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE high-T-c superconductors; two-dimensional systems; spin waves; antiferromagnetism ID HEISENBERG-ANTIFERROMAGNET AB The spin excitations in La2CuO4, a two-dimensional spin-1/2 Heisenberg antiferromagnet and parent compound of high-T-c, superconductors, have been measured throughout the Brillouin zone using high-resolution inelastic neutron scattering. The observed dispersion relations show evidence for substantial second- or third-nearest-neighbour exchange couplings in addition to the strong first nearest-neighbour antiferromagnetic exchange. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. NEC Res Inst, Princeton, NJ 08540 USA. Lucent Technol, Murray Hill, NJ 07974 USA. Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. RP Coldea, R (reprint author), Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England. RI Hayden, Stephen/F-4162-2011; Mason, Thomas/M-5809-2014 OI Hayden, Stephen/0000-0002-3209-027X; Mason, Thomas/0000-0003-1880-3971 NR 8 TC 5 Z9 5 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 592 EP 593 DI 10.1016/S0921-4526(99)01772-X PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000265 ER PT J AU Caspi, EN Melamud, M Pinto, H Shaked, H Chmaissem, O Jorgensen, JD Short, S AF Caspi, EN Melamud, M Pinto, H Shaked, H Chmaissem, O Jorgensen, JD Short, S TI Phase separation and magnetic ordering studied by high-resolution neutron diffraction SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE actinides; antiferromagnetism; powder diffraction; neutron time-of-flight diffraction AB High-resolution neutron diffraction study of the U1-xNdxCo2Ge2 (x = 0.25) compound shows a separation into two phases, each order antiferromagnetically at a different temperature. The temperature dependence of the magnetic moment is deduced for both phases. The results are in agreement with previous low-resolution neutron diffraction measurements, (C) 2000 Elsevier Science B.V. All rights reserved. C1 Ben Gurion Univ Negev, Dept Phys, IL-84105 Beer Sheva, Israel. Nucl Res Ctr Negev, IL-84190 Beer Sheva, Israel. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Caspi, EN (reprint author), Ben Gurion Univ Negev, Dept Phys, POB 653, IL-84105 Beer Sheva, Israel. NR 3 TC 1 Z9 1 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 604 EP 605 DI 10.1016/S0921-4526(99)01370-8 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000271 ER PT J AU Chang, S Nakotte, H Schultz, AJ Bordallo, HN Torikachvili, MS Sechovsky, V Andreev, AV AF Chang, S Nakotte, H Schultz, AJ Bordallo, HN Torikachvili, MS Sechovsky, V Andreev, AV TI Crystallographic order and magnetism in UCo1/3T2/3Al compounds (T = Ru, Rh, Pt) SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE uranium intermetallics; hybridization; crystal structure; magnetic structure ID TERNARY AB We report on neutron diffraction studies of UCo1/3T2/3Al solid solutions, where T = Ru, Pt or Rh. Preferential occupation of two non-equivalent sites by the transition metals was determined for each compound. In addition, long-range magnetic order was confirmed for all three compounds. Correlations between the crystallographic and magnetic structures are discussed in terms of the Sf-ligand hybridization. (C) 2000 Elsevier Science B.V. All rights reserved. C1 New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. San Diego State Univ, Dept Phys, San Diego, CA 92182 USA. Charles Univ, Dept Elect Struct, Prague 12116 2, Czech Republic. RP Chang, S (reprint author), New Mexico State Univ, Dept Phys, POB 30001, Las Cruces, NM 88003 USA. RI Andreev, Alexander/B-6057-2011; Bordallo, Heloisa/I-6836-2012; Sechovsky, Vladimir/A-5256-2008 OI Bordallo, Heloisa/0000-0003-0750-0553; Sechovsky, Vladimir/0000-0003-1298-2120 NR 6 TC 0 Z9 0 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 634 EP 635 DI 10.1016/S0921-4526(99)01389-7 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000286 ER PT J AU Goff, JP Sarthour, RS McMorrow, DF Yakhou, F Vigliante, A Gibbs, D Ward, RCC Wells, MR AF Goff, JP Sarthour, RS McMorrow, DF Yakhou, F Vigliante, A Gibbs, D Ward, RCC Wells, MR TI Diffuse magnetic scattering from DHCP HoxCe1-x alloys SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE rare earth metals; diffuse scattering and hybridisation AB The magnetic ordering in HoxCe1-x alloys has been investigated by neutron diffraction and X-ray magnetic resonant scattering (XMRS). The DHCP alloys display a rich phase diagram, and highly unusual, diffuse neutron magnetic scattering is observed over the composition range 0.35 less than or equal to x less than or equal to 0.5. The diffuse intensity may be the magnetic response of the conduction band, and this interpretation is supported by the XMRS measurements, which show that there is hybridisation of the Ce 4f electron with the conduction electrons. (C) 2000 Elsevier science B.V. All rights reserved. C1 Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Riso Natl Lab, 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 Liverpool, Dept Phys, Oliver Lodge Lab, Oxford St, Liverpool L69 7ZE, Merseyside, England. RI McMorrow, Desmond/C-2655-2008 OI McMorrow, Desmond/0000-0002-4947-7788 NR 7 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 696 EP 697 DI 10.1016/S0921-4526(99)01803-7 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000317 ER PT J AU Bordallo, HN Nakotte, H Kolomiets, AV Christianson, A Havela, L Schultz, AJ Drulis, H Iwasieczko, W AF Bordallo, HN Nakotte, H Kolomiets, AV Christianson, A Havela, L Schultz, AJ Drulis, H Iwasieczko, W TI Properties of UNiAlD2.1 and UNiAlH2.3 SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE crystal structure; heavy fermion; magnetic order; powder diffraction AB Neutron diffraction and bulk magnetic studies have been performed in UNiAID(2.1), and UNiA.lHa(2.3). Due to the lattice expansion and weakening of the 5f-ligand hybridization, UNiAlD2.1 orders magnetically at a much higher temperature than the isostructural UNiAl. (C) 2000 Elsevier Science B.V. AII rights reserved. C1 Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. Charles Univ, Dept Elect Struct, Prague 12116 2, Czech Republic. Colorado State Univ, Dept Phys, Ft Collins, CO 80523 USA. Polish Acad Sci, W Trzebiatowski Inst Low Temp & Struct Res, PL-50950 Wroclaw, Poland. RP Bordallo, HN (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Bordallo, Heloisa/I-6836-2012; christianson, andrew/A-3277-2016 OI Bordallo, Heloisa/0000-0003-0750-0553; christianson, andrew/0000-0003-3369-5884 NR 5 TC 12 Z9 12 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 706 EP 707 DI 10.1016/S0921-4526(99)01810-4 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000322 ER PT J AU Coad, S Hiess, A McMorrow, DF Lander, GH Aeppli, G Fisk, Z Stewart, GR Hayden, SM Mook, HA AF Coad, S Hiess, A McMorrow, DF Lander, GH Aeppli, G Fisk, Z Stewart, GR Hayden, SM Mook, HA TI Magnetic response in UBe13 SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE heavy fermions; magnetic correlations; superconductors; neutron scattering AB Uranium-based heavy-fermion superconductors have attracted interest because of the opportunity to study the interplay between magnetism and superconductivity. All of these materials have been found to order antiferromagnetically with T-N > T-c with the exception of UBe13 in which no neutron evidence for static magnetism has been reported. In experiments on single crystals at Riso National Lab., we have observed antiferromagnetic short-range magnetic correlations situated at q = < 0.5,0.5,0 >. Their breadth in q-space shows that the correlations are short range; while the absence of a signal in certain directions suggests that the components we observe are longitudinally polarised with respect to their propagation vector. In energy space, the correlations extend to similar to 2 meV and no signal is observable for T > 30 K. The remaining question concerns the energy dependence of this response around T-c. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. Inst Transuranium Elements, D-76125 Karlsruhe, Germany. Riso Natl Lab, DK-4000 Roskilde, Denmark. NEC Res Inst, Princeton, NJ 08540 USA. Natl Magnet Field Lab, Tallahassee, FL 32306 USA. Univ Florida, Dept Phys, Gainesville, FL 32611 USA. Univ Bristol, Bristol BS8 1TH, Avon, England. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hiess, A (reprint author), Inst Max Von Laue Paul Langevin, BP 156, F-38042 Grenoble, France. RI McMorrow, Desmond/C-2655-2008; Hayden, Stephen/F-4162-2011 OI McMorrow, Desmond/0000-0002-4947-7788; Hayden, Stephen/0000-0002-3209-027X NR 2 TC 9 Z9 9 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 764 EP 765 DI 10.1016/S0921-4526(99)01285-5 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000349 ER PT J AU Katano, S Fernandez-Baca, JA Yamada, Y AF Katano, S Fernandez-Baca, JA Yamada, Y TI Phase transitions, diffuse scattering and segregation kinetics in the colossal magnetoresistance material Pr70Ca30MnO3 SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE colossal magnetoresistance; Pr70Ca30MO3; diffuse scattering; segregation kinetics ID NEUTRON-DIFFRACTION; PR0.7CA0.3MNO3 AB The successive phase transitions to the charge-ordered (CO), antiferromagnetic (AFM) and ferromagnetic (FM) states in Pr70Ca30MnO3, as well as the enhancement of the FM state by the application of a magnetic field, have been studied using neutron diffraction. FM diffuse scattering that persists down to low temperatures indicates the existence of FM clusters. The relaxation process from a metastable FM to a CO and AFM state reveals percolative nature of the dramatic metal-to-insulator transition of this system. These results show that the system is phase-separated. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Japan Atom Energy Res Inst, Adv Sci Res Ctr, Neutron Scattering Grp, Tokai, Ibaraki 3191195, Japan. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Waseda Univ, Adv Res Ctr Sci & Engn, Shinjyuku Ku, Tokyo 1690072, Japan. RP Katano, S (reprint author), Japan Atom Energy Res Inst, Adv Sci Res Ctr, Neutron Scattering Grp, Tokai, Ibaraki 3191195, Japan. RI Fernandez-Baca, Jaime/C-3984-2014 OI Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 5 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 786 EP 787 DI 10.1016/S0921-4526(99)01644-0 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000360 ER PT J AU Ioffe, A Arif, M Jacobson, D Mezei, F AF Ioffe, A Arif, M Jacobson, D Mezei, F TI Does quantum entanglement invalidate contrast variation practices in neutron scattering? SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE interferometry; small-angle neutron scattering ID CONDENSED MATTER AB A surprising observation of the anomalous deep inelastic neutron scattering from liquid H2O-D2O mixtures was reported recently in PRL. It has also been suggested that such anomalous scattering can manifest itself as a deviation of the neutron scattering length density Nb from the conventional theory, based upon the assumption that the molecular volumes of the constituents are additive in the mixture. For H2O-D2O mixtures deviations as much as 5-10% are predicted from the conventionally expected value Nb. This fact would result in serious consequences for the widely used technique of contrast variation in neutron scattering. We have used an advanced neutron interferometry technique in order to verify these predictions and confirmed the experimental practice of isotopic contrast variation with high precision. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. RP Ioffe, A (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,Stop 8461, Gaithersburg, MD 20899 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 952 EP 953 DI 10.1016/S0921-4526(99)01685-3 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000435 ER PT J AU Mezei, F Ioffe, A Fischer, P Arif, M Jacobson, DL AF Mezei, F Ioffe, A Fischer, P Arif, M Jacobson, DL TI Observation of 4 pi-symmetry of the neutron wave function under space rotation SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE neutron interferometry ID PRECESSION AB We observed 4 pi-symmetry of the neutron Rave function under rotation in space produced by slowly rotating an adiabatic guide field. In contrast to all previous works, the present experiment is of purely topological nature, i.e. it does not involve the Larmor precession and the result depends only on the topology and not on the value of the magnetic field and the neutron magnetic moment. This is the first experimental observation which cannot be explained by simply applying the common concept of wave optical dynamic phase, consistently with the Stern-Gerlach spin quantization, to each of the "spin-up" and "spin-down" energy eigenstates superposed in the neutron wave function. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ioffe, A (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,Stop 8461, Gaithersburg, MD 20899 USA. 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 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 979 EP 980 DI 10.1016/S0921-4526(99)01530-6 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000447 ER PT J AU Mezei, F Ehlers, G Pappas, C Russina, M Hicks, TJ Ling, MF AF Mezei, F Ehlers, G Pappas, C Russina, M Hicks, TJ Ling, MF TI What neutrons do tell us about the nature of (spin) glasses? SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Studsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Corp, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE spin glasses; glasses; disordered materials ID DYNAMICS AB A common feature of all glassy systems is the decisive role of dynamics in the evolution of macroscopic properties, while the short and eventually partial long-range order shows little difference between the different phases. Our recent neutron scattering results on a Cu-Mn spin glass dramatically illustrate this point, and provide unambiguous evidence against recent suggestions that behaviour in Cu-Mn is driven by spin density waves rather than glassy dynamics. Recent findings in Au-Fe provide the first circumstantial evidence for the theoretically predicted extremely long correlation lengths at the spin-glass transition. Recent experimental advances opened up the way to investigate dynamics in glasses and liquids on extended length scales, where only spin correlations could be studied by now. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Hahn Meitner Inst Berlin GmbH, Berlin Neutron Ctr, D-14109 Berlin, Germany. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Monash Univ, Dept Phys, Clayton, Vic 3168, Australia. RP Glienicker Str 100, D-14109 Berlin, Germany. EM mezei@hmi.de RI Ehlers, Georg/B-5412-2008; Russina, Margarita/E-9886-2016 OI Ehlers, Georg/0000-0003-3513-508X; Russina, Margarita/0000-0003-2067-606X NR 13 TC 3 Z9 3 U1 1 U2 5 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 MAR PY 2000 VL 276 BP 543 EP 546 DI 10.1016/S0921-4526(99)01364-2 PG 4 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000242 ER PT J AU Cha, YS AF Cha, YS TI Magnetic diffusion in high-T-c superconductors SO PHYSICA C LA English DT Article DE magnetic diffusion; pulsed current experiments; high-T-c superconductors; critical state model ID FIELD AB An equation for nonlinear magnetic diffusion is derived for high-temperature (high-T-c) superconductors by using the power law for the electric field/current density relationship in the flux creep regime. Limitation of the Bean's critical-scare model in a transient experiment is discussed, Some experimental evidence for magnetic diffusion in high-T-c superconductors is provided. Effects of dissipation and heating on magnetic diffusion are discussed. (C) 2000 Elsevier Science B,V. All rights reserved. C1 Argonne Natl Lab, Energy Technol Div 335, Argonne, IL 60439 USA. RP Cha, YS (reprint author), Argonne Natl Lab, Energy Technol Div 335, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 9 TC 17 Z9 17 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 MAR 1 PY 2000 VL 330 IS 1-2 BP 1 EP 8 DI 10.1016/S0921-4534(99)00584-5 PG 8 WC Physics, Applied SC Physics GA 286QQ UT WOS:000085457000001 ER PT J AU Kurdak, C Rimberg, AJ Ho, TR Clarke, J Walker, JD AF Kurdak, C Rimberg, AJ Ho, TR Clarke, J Walker, JD TI Controlling the charging energy of arrays of tunnel junctions SO PHYSICA E LA English DT Article DE Josephson junction array; charging energy; three-dimensional electron gas ID SINGLE-ELECTRON SOLITONS; 2-DIMENSIONAL ARRAYS; JOSEPHSON-JUNCTIONS; DYNAMICS; TRANSITION; MOTION AB We describe a new technique to control in situ charging energy of systems of coupled metallic or superconducting islands. To illustrate the technique, we have fabricated two-dimensional arrays of Al islands on GaAs/AlAs hterostructures. Each island is coupled to its nearest-neighbor by a submicron Al/AlOx/Al tunnel junction and to the three-dimensional electron gas (3DEG) located below the surface of the heterostructure by a capacitance C-g. We vary C-g, which dominates the charging energy of the array, by depleting the electrons in the 3DEG by means of a negative voltage applied to the array. With the array driven normal by a magnetic field, a decrease in C-g increases in both the offset voltage and the period of the Coulomb blockade oscillations. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Kurdak, C (reprint author), Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. RI Rimberg, Alexander/B-8076-2010 NR 26 TC 3 Z9 3 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1386-9477 J9 PHYSICA E JI Physica E PD MAR PY 2000 VL 5 IS 4 BP 274 EP 279 DI 10.1016/S1386-9477(99)00258-1 PG 6 WC Nanoscience & Nanotechnology; Physics, Condensed Matter SC Science & Technology - Other Topics; Physics GA 295XZ UT WOS:000085995100002 ER PT J AU Riva, C Peeters, FM Varga, K AF Riva, C Peeters, FM Varga, K TI Ground state of excitons and charged excitons in a quantum well SO PHYSICA STATUS SOLIDI A-APPLIED RESEARCH LA English DT Article; Proceedings Paper CT 6th International Conference on Optics of Excitons in Confined Systems (OECS-6) CY AUG 30-SEP 02, 1999 CL ASCONA, SWITZERLAND ID TRANSITIONS; FIELD AB A variational calculation of the ground state of a neutral exciton and of positively and negatively charged excitons (trions) in a single quantum well is presented. We study the dependence of the correlation energy and of the binding energy on the well width and on the hole mass. Our results are compared with previous theoretical results and with available experimental data. C1 Univ Instelling Antwerp, Dept Natuurkunde, B-2610 Wilrijk, Belgium. Argonne Natl Lab, Dept Phys, Argonne, IL 60439 USA. RP Riva, C (reprint author), Univ Instelling Antwerp, Dept Natuurkunde, B-2610 Wilrijk, Belgium. RI Varga, Kalman/A-7102-2013; CMT, UAntwerpen Group/A-5523-2016 NR 11 TC 12 Z9 12 U1 0 U2 0 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0031-8965 J9 PHYS STATUS SOLIDI A JI Phys. Status Solidi A-Appl. Res. PD MAR PY 2000 VL 178 IS 1 BP 513 EP 517 DI 10.1002/1521-396X(200003)178:1<513::AID-PSSA513>3.0.CO;2-1 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 303TG UT WOS:000086440500089 ER PT J AU Aselage, TL Emin, D McCready, SS AF Aselage, TL Emin, D McCready, SS TI Bipolaron hopping conduction in boron carbides SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Article; Proceedings Paper CT 8th International Conference on Hopping and Related Phenomena (HRP8) CY SEP 07-10, 1999 CL MURCIA, SPAIN SP Spanish Direc Gen Ensenanza Superior, Fdn Seneca, Univ Murcia AB The electrical conductivities of boron carbides, B12+xC3-x With 0.1 < x < 1.7, between 300 and 1200 K suggest the hopping of a nearly temperature-independent density of small (bi)polarons. The activation energies of the mobilities are low, approximate to 0.16 eV, and are nearly independent of the composition. At lower temperatures, conductivities have non-Arrhenius temperature dependencies and strong sensitivity to carbon concentration. Percolative aspects of low-temperature hopping are evident in this sensitivity to composition. Boron carbides' Seebeck coefficients are anomalous in that 1. they are much larger than expected from boron carbides' large carrier densities and 2. they depend only weakly on the carrier density. Carrier-induced softening of local vibrations gives contributions to the Seebeck coefficient that mirror the magnitudes and temperature dependencies found in boron carbides. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. RP Aselage, TL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 9 Z9 9 U1 0 U2 5 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD MAR PY 2000 VL 218 IS 1 BP 255 EP 258 DI 10.1002/(SICI)1521-3951(200003)218:1<255::AID-PSSB255>3.0.CO;2-S PG 4 WC Physics, Condensed Matter SC Physics GA 303PJ UT WOS:000086431000052 ER PT J AU Guo, CL Li, M Nibarger, JP Gibson, GN AF Guo, CL Li, M Nibarger, JP Gibson, GN TI Nonsequential double ionization of molecular fragments SO PHYSICAL REVIEW A LA English DT Article ID MULTIELECTRON DISSOCIATIVE IONIZATION; STRONG LASER FIELDS; DIATOMIC-MOLECULES; HELIUM; HE; DEPENDENCE; PULSE AB High-precision ion yields are taken with 30-fs ultrashort laser pulses in various species of doubly ionized diatomic molecules, N-2 and O-2, including metastable, charge symmetric, and asymmetric dissociating channels. The experimental results indicate that the detailed electronic structure is a critical factor influencing strong field nonsequential ionization. The study of ellipticity effects of nonsequential ionization is also extended, for the first time to our knowledge, to the molecular system. C1 Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. RP Guo, CL (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. NR 22 TC 49 Z9 49 U1 1 U2 7 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 MAR PY 2000 VL 61 IS 3 BP art. no. EP 033413 DI 10.1103/PhysRevA.61.033413 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 293DM UT WOS:000085836300083 ER PT J AU Kielpinski, D King, BE Myatt, CJ Sackett, CA Turchette, QA Itano, WM Monroe, C Wineland, DJ Zurek, WH AF Kielpinski, D King, BE Myatt, CJ Sackett, CA Turchette, QA Itano, WM Monroe, C Wineland, DJ Zurek, WH TI Sympathetic cooling of trapped ions for quantum logic SO PHYSICAL REVIEW A LA English DT Article ID LINEAR PAUL TRAP; PHASE-TRANSITIONS; CRYSTALS; STATE AB One limit to the fidelity of quantum logic operations on trapped ions arises from heating of the ions' collective modes of motion. Sympathetic cooling of the ions during the logic operations may eliminate this source of errors. We discuss the benefits and drawbacks of this proposal, and describe possible experimental implementations. We also present an overview of trapped-ion dynamics in this scheme. C1 Natl Inst Stand & Technol, Div Time & Frequency, Boulder, CO 80303 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kielpinski, D (reprint author), Natl Inst Stand & Technol, Div Time & Frequency, Boulder, CO 80303 USA. RI Monroe, Christopher/G-8105-2011 NR 17 TC 73 Z9 75 U1 2 U2 16 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 MAR PY 2000 VL 61 IS 3 BP art. no. EP 032310 DI 10.1103/PhysRevA.61.032310 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 293DM UT WOS:000085836300034 ER PT J AU Utter, SB Beiersdorfer, P Brown, GV AF Utter, SB Beiersdorfer, P Brown, GV TI Measurement of an unusual M1 transition in the ground state of Ti-like W52+ SO PHYSICAL REVIEW A LA English DT Article AB Using a high-efficiency, transmission grating spectrometer the 3s(2)3p(6)3d(4) J = 2-3 ground-state transition was measured in Ti-like W52+. The measurement has achieved 20 times better precision than the only previously reported high-Z measurement. As such, it tests recent structure calculations for complex highly charged ions. Discrepancies of around 100 Angstrom are found. This is true even for semi-empirical calculations. The measurement, however, validates a very recent calculation with which agreement is within 2 Angstrom. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Utter, SB (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 14 TC 44 Z9 44 U1 2 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAR PY 2000 VL 61 IS 3 BP art. no. EP 030503 DI 10.1103/PhysRevA.61.030503 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 293DM UT WOS:000085836300004 ER PT J AU Kimura, M Gu, JP Hirsch, G Buenker, RJ Stancil, PC AF Kimura, M Gu, JP Hirsch, G Buenker, RJ Stancil, PC TI Electron capture in collisions of protons with CO molecules in the keV region: The steric effect SO PHYSICAL REVIEW A LA English DT Article ID CHARGE-TRANSFER PROCESSES; CI CALCULATIONS; ENERGY EXTRAPOLATION; INELASTIC PROCESSES; MATRIX-ELEMENTS; CARBON-MONOXIDE; EXCITED-STATES; CROSS-SECTIONS; ION; IONIZATION AB Electron capture resulting from collisions of H+ ions with CO molecules has been investigated based on the molecular representation within the fully quantum-mechanical formalism below 10 keV/u. Three different molecular configurations have been considered for collision dynamics, i.e., (i) the proton approaches the center of mass of the CO molecule in the perpendicular configuration, (ii) the proton approaches the C atom in the collinear configuration, and (iii) the proton approaches the O atom in the collinear configuration. Electron-capture dynamics and corresponding capture cross sections depend very sensitively on the molecular configuration, thus revealing a strong steric effect. The capture cross section from the CO electronic ground slate is about 1.3 x 10(-15) cm(2) at 10 keV/u, which is in good agreement with experimental findings. Differential cross sections (DCS's) for three molecular orientations have been examined both for elastic and electron-capture processes, and the DCS averaged over all the configurations was found to agree well with a measurement from 0.02 degrees to 1 degrees at 1.5 keV/u. C1 Berg Univ Gesamthsch Wuppertal, D-42097 Wuppertal, Germany. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Yamaguchi Univ, Sch Med, Ube, Yamaguchi 755, Japan. RP Kimura, M (reprint author), Berg Univ Gesamthsch Wuppertal, D-42097 Wuppertal, Germany. NR 28 TC 26 Z9 26 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAR PY 2000 VL 61 IS 3 AR 032708 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 293DM UT WOS:000085836300051 ER PT J AU Nieto, MM AF Nieto, MM TI Electrons above a helium surface and the one-dimensional Rydberg atom SO PHYSICAL REVIEW A LA English DT Article ID LIQUID-HELIUM; HYDROGEN-ATOM; QUANTUM-MECHANICS; WAVE-FUNCTIONS; SUPERSYMMETRY; HAMILTONIANS; POTENTIALS AB Isolated electrons resting above a helium surface are predicted to have a bound spectrum corresponding to a one-dimensional hydrogen atom. But in fact, the observed spectrum is closer to that of a quantum-defect atom. Such a model is discussed and solved in analytic closed form. C1 Univ Calif Los Alamos Natl Lab, Theoret Div MS B285, Los Alamos, NM 87545 USA. RP Nieto, MM (reprint author), Univ Calif Los Alamos Natl Lab, Theoret Div MS B285, Los Alamos, NM 87545 USA. NR 38 TC 6 Z9 6 U1 2 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAR PY 2000 VL 61 IS 3 AR 034901 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 293DM UT WOS:000085836300125 ER PT J AU Raghavan, S Kenkre, VM Bishop, AR AF Raghavan, S Kenkre, VM Bishop, AR TI Dynamic localization in spin systems SO PHYSICAL REVIEW B LA English DT Article ID ELECTRIC-FIELD; MAGNETIZATION; PARTICLE AB A dilute collection of spins, when driven coherently by crossed magnetic fields of arbitrary and controllable time dependences along the three Cartesian directions, is shown to exhibit a striking phenomenon in which the azimuthal quantum number remains unchanged for certain resonant combinations of the field intensities and field frequencies. The formalism of dynamic localization available for the area of charge transport in crystals is shown to provide an approximate but highly efficient analytic method for the study of this phenomenon. The effect on scattering of probe particles is elucidated. C1 Univ Rochester, Rochester Theory Ctr Opt Sci & Engn, Dept Phys & Astron, Rochester, NY 14627 USA. Univ New Mexico, Ctr Adv Studies, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Univ Rochester, Rochester Theory Ctr Opt Sci & Engn, Dept Phys & Astron, 601 Elmwood Ave, Rochester, NY 14627 USA. NR 22 TC 5 Z9 5 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 9 BP 5864 EP 5867 DI 10.1103/PhysRevB.61.5864 PG 4 WC Physics, Condensed Matter SC Physics GA 290ZE UT WOS:000085707100013 ER PT J AU Vavassori, P Metlushko, V Grimsditch, M Ilic, B Neuzil, P Kumar, R AF Vavassori, P Metlushko, V Grimsditch, M Ilic, B Neuzil, P Kumar, R TI Magneto-optical studies of superlattice dot arrays SO PHYSICAL REVIEW B LA English DT Article ID INTERFEROMETRIC LITHOGRAPHY; INTERFERENCE LITHOGRAPHY; MAGNETIZATION REVERSAL; HOLE ARRAYS; DIFFRACTION; PHOTORESIST; ANISOTROPY AB We have investigated the magnetic properties of a dot array that contains two nonidentical dots per unit cell. As expected, this structure produces a diffraction pattern consisting of intense and weak spots that results from in- and out-of-phase contributions of the two sublattices. A comparison of the magneto-optical Kerr measurements on the weak and strong diffraction spots enables the switching of the two sublattices to be determined independently. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Illinois, Microfabricat & Applicat Lab, Dept Elect Engn & Comp Sci, Chicago, IL 60607 USA. Inst Microelect, Singapore 117685, Singapore. RP Vavassori, P (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Neuzil, Pavel/B-9981-2012; Ilic, Rob/N-1359-2014; Vavassori, Paolo/B-4299-2014 OI Vavassori, Paolo/0000-0002-4735-6640 NR 26 TC 27 Z9 27 U1 0 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 9 BP 5895 EP 5898 DI 10.1103/PhysRevB.61.5895 PG 4 WC Physics, Condensed Matter SC Physics GA 290ZE UT WOS:000085707100021 ER PT J AU Klemm, RA Rieck, CT Scharnberg, K AF Klemm, RA Rieck, CT Scharnberg, K TI Order-parameter symmetries in high-temperature superconductors SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; BI2SR2CACU2O8 AB We present two representations of the order-parameter (OP) eigenfunctions for tetragonal cuprate superconductors, and for orthorhombic YBa2Cu3O7-delta and Bi2Sr2CaCu2O8+delta (BSCCO). Recent BSCCO c-axis twist Josephson junction experiments of Li et al. demonstrate that the tunneling is strongly incoherent, and that the OP contains an isotropic s-wave component, but not any d(x2-y2)-wave component. We propose a c-axis twist tetracrystal ring experiment. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Hamburg, Fachbereich Phys, D-20355 Hamburg, Germany. RP Klemm, RA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 19 TC 33 Z9 33 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 MAR 1 PY 2000 VL 61 IS 9 BP 5913 EP 5916 DI 10.1103/PhysRevB.61.5913 PG 4 WC Physics, Condensed Matter SC Physics GA 290ZE UT WOS:000085707100026 ER PT J AU Nelson, DR Vinokur, VM AF Nelson, DR Vinokur, VM TI Bose glass scaling for superconducting vortex arrays revisited SO PHYSICAL REVIEW B LA English DT Article ID TWINNED YBA2CU3O7-DELTA; COLUMNAR DEFECTS; TRANSITION; PHASE; LOCALIZATION AB Lidmar and Wallin have recently pointed out that Bose glass scaling theory predicts a linear cusp in the phase boundary of vortex matter with correlated disorder as a function temperature of temperature and perpendicular magnetic field. Here, we collect a number of consequences of this observation for physical quantities near the Bose glass transition. C1 Harvard Univ, Lyman Lab Phys, Cambridge, MA 02138 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Nelson, DR (reprint author), Harvard Univ, Lyman Lab Phys, Cambridge, MA 02138 USA. NR 13 TC 13 Z9 13 U1 1 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 9 BP 5917 EP 5919 DI 10.1103/PhysRevB.61.5917 PG 3 WC Physics, Condensed Matter SC Physics GA 290ZE UT WOS:000085707100027 ER PT J AU Abrikosov, AA AF Abrikosov, AA TI Linear c-axis magnetoresistance in underdoped YBa2Cu3O6+delta SO PHYSICAL REVIEW B LA English DT Article AB The observed linear magnetoresistance along the c axis in underdoped YBa2Cu3O6+delta with H parallel to c is explained as a consequence of reduced coherence between resonant tunneling through different centers due to Landau quantization of the transverse motion in magnetic field. The linear dependence appears when only the lowest quantized state participates in tunneling, and in this respect it resembles the quantum linear magnetoresistance in semimetals. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Abrikosov, AA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 4 TC 3 Z9 3 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 MAR 1 PY 2000 VL 61 IS 9 BP 5928 EP 5929 DI 10.1103/PhysRevB.61.5928 PG 2 WC Physics, Condensed Matter SC Physics GA 290ZE UT WOS:000085707100030 ER PT J AU Katz, AS Woods, SI Singley, EJ Li, TW Xu, M Hinks, DG Dynes, RC Basov, DN AF Katz, AS Woods, SI Singley, EJ Li, TW Xu, M Hinks, DG Dynes, RC Basov, DN TI Interlayer conductivity in the superconductor Tl2Ba2CuO6+delta: Energetics and energy scales SO PHYSICAL REVIEW B LA English DT Article ID GAP ANISOTROPY; PENETRATION DEPTH; DOPING LEVEL; OPTICAL-SPECTRUM; SUM-RULE; STATE; MODEL; TEMPERATURE; YBA2CU4O8; PLANE AB We report on infrared studies of the c-axis electrodynamics of Tl2Ba2CuO6+delta crystals. A sum-rule analysis reveals spectral weight shifts that can be interpreted as a kinetic energy change at the superconducting transition. In optimally doped crystals, showing an incoherent normal-state response, the kinetic energy is lowered at TT-c. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Argonne Natl Lab, Dept Mat Sci, Argonne, IL 60439 USA. Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. RP Xu, M (reprint author), Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. NR 36 TC 42 Z9 42 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 MAR 1 PY 2000 VL 61 IS 9 BP 5930 EP 5933 DI 10.1103/PhysRevB.61.5930 PG 4 WC Physics, Condensed Matter SC Physics GA 290ZE UT WOS:000085707100031 ER PT J AU Grove, M Lemmens, P Guntherodt, G Sales, BC Bullesfeld, F Assmus, W AF Grove, M Lemmens, P Guntherodt, G Sales, BC Bullesfeld, F Assmus, W TI Magnetoelastic coupling and spin excitations in the spin-gap system (VO)(2)P2O7: A Raman scattering study SO PHYSICAL REVIEW B LA English DT Article ID HEISENBERG-ANTIFERROMAGNET; MAGNETIC EXCITATIONS; LIGHT-SCATTERING; PEIERLS SYSTEMS; CUGEO3; CHAIN; SUSCEPTIBILITY; FLUCTUATIONS; SPECTRUM; LADDER AB Single crystals of the spin-gap system (VO)(2)P2O7 have been investigated by means of Raman scattering. At temperatures below T = 75 K approximate to 2 Delta(01)(k = 0), with Delta(01) the singlet-triplet gap, a shoulder appears at 47 cm(-1). An analysis of the polarization selection rules and the temperature dependence of the scattering intensity leads to its identification as a singlet bound state with very small binding energy. Therefore in contrast to recent theoretical models the importance of frustration for this compound must be rejected. The observation of a strong anharmonicity of three phonons with energies close to Delta(01) at the zone boundary and additional quasielastic light scattering, however, both point to a strong spin-phonon coupling in this system. We propose this coupling to be the origin of the second bound triplet state observed in recent neutron-scattering experiments. C1 Rhein Westfal TH Aachen, Inst Phys 2, D-52056 Aachen, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Frankfurt, Inst Phys, D-60054 Frankfurt, Germany. RP Grove, M (reprint author), Rhein Westfal TH Aachen, Inst Phys 2, D-52056 Aachen, Germany. RI Lemmens, Peter/C-8398-2009 OI Lemmens, Peter/0000-0002-0894-3412 NR 38 TC 22 Z9 22 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 MAR 1 PY 2000 VL 61 IS 9 BP 6126 EP 6132 DI 10.1103/PhysRevB.61.6126 PG 7 WC Physics, Condensed Matter SC Physics GA 290ZE UT WOS:000085707100055 ER PT J AU de Reotier, PD Yaouanc, A Heffner, RH Smith, JL Gubbens, PCM Kaiser, CT AF de Reotier, PD Yaouanc, A Heffner, RH Smith, JL Gubbens, PCM Kaiser, CT TI Muon spin relaxation and rotation measurements on single crystals of the heavy-fermion superconductor UBe13 SO PHYSICAL REVIEW B LA English DT Article ID MAGNETIC-FIELD; ZERO-FIELD; UPT3; (U,TH)BE13; PHASE AB We report zero-, longtudinal-, and transverse-field positive muon spin relaxation (mu SR) measurements in single crystals of the heavy-fermion superconductor UBe13 [T-c=0.83(2) K]. Our zero-field measurements provide an upper limit for any quasistatic magnetic moments in this system below 100 K of 0.001 mu(B), consistent with previous measurements on polycrystals. From the transverse-field measurements we rind a lower bound for the London penetration depth lambda(L) = 1210 nm. This value implies a lower limit for the effective mass consistent with the low-temperature specific heat. C1 Commissariat Energie Atom, Dept Rech Fondamentale Mat Condensee, F-38054 Grenoble 9, France. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Delft Univ Technol, Interfac Reactor Inst, NL-2629 JB Delft, Netherlands. RP de Reotier, PD (reprint author), Commissariat Energie Atom, Dept Rech Fondamentale Mat Condensee, F-38054 Grenoble 9, France. NR 26 TC 7 Z9 7 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 9 BP 6377 EP 6380 DI 10.1103/PhysRevB.61.6377 PG 4 WC Physics, Condensed Matter SC Physics GA 290ZE UT WOS:000085707100085 ER PT J AU Chmaissem, O Jorgensen, JD Shaked, H Dollar, P Tallon, JL AF Chmaissem, O Jorgensen, JD Shaked, H Dollar, P Tallon, JL TI Crystal and magnetic structure of ferromagnetic superconducting RuSr2GdCu2O8 SO PHYSICAL REVIEW B LA English DT Article AB The crystal and magnetic structure of a sample of (RuSr2GdCu2O8)-Gd-160 which orders magnetically at 133 K and exhibits a superconducting transition at 35 K has been investigated by neutron powder diffraction. RuO6 octahedra, which substitute at the chain copper site in a YBa2Cu3O7-type structure, are rotated by about 14 degrees around the c axis to accommodate physically reasonable Ru-O bond lengths in the plane. This results in a root 2a(p) X root 2a(p) X c supercell. The RuO6 rotations are partially ordered to form competing domains that differ in the sense of rotation. We speculate that the degree of ordering depends on annealing conditions. Surprisingly, the only structural parameters that respond to the magnetic ordering at 133 K are the Cu-Cu distance, which defines the thickness of the CuO2 double layer, and the buckling angle of the CuO2 planes. Magnetic scattering consistent with the previously proposed ferromagnetic ordering of Ru moments perpendicular to the c axis is not observed. We do not rule out ordering of Ru moments parallel to the c axis or itinerant ferromagnetism. C1 No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Ind Res Ltd, Lower Hutt, New Zealand. Ben Gurion Univ Negev, Dept Phys, IL-84190 Beer Sheva, Israel. RP No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. NR 16 TC 201 Z9 204 U1 1 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 9 BP 6401 EP 6407 DI 10.1103/PhysRevB.61.6401 PG 7 WC Physics, Condensed Matter SC Physics GA 290ZE UT WOS:000085707100088 ER PT J AU Yang, FY Liu, K Hong, KM Reich, DH Searson, PC Chien, CL Leprince-Wang, Y Kui, YZ Han, K AF Yang, FY Liu, K Hong, KM Reich, DH Searson, PC Chien, CL Leprince-Wang, Y Kui, YZ Han, K TI Shubnikov-de Haas oscillations in electrodeposited single-crystal bismuth films SO PHYSICAL REVIEW B LA English DT Article ID SEMICONDUCTOR TRANSITION; THIN-FILMS; BI; NANOWIRES; GROWTH AB Shubnikov-de Haas oscillations have been observed in Bi thin films fabricated by electrodeposition. The observed dominant oscillation periods of 0.17, 0.08, and 0.077 T-1, with the magnetic field along the trigonal, binary, and bisectrix axes of Bi, respectively, are in good agreement with those in bulk Bi single crystals. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Johns Hopkins Univ, Dept Mat Sci & Engn, Baltimore, MD 21218 USA. Univ Marne La Vallee, Dept Phys, F-77454 Marne La Vallee 2, France. Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. RP Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RI Searson, Peter /A-3311-2010; Liu, Kai/B-1163-2008; OI Liu, Kai/0000-0001-9413-6782; Searson, Peter/0000-0002-5417-0828 NR 17 TC 34 Z9 34 U1 1 U2 10 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 10 BP 6631 EP 6636 DI 10.1103/PhysRevB.61.6631 PG 6 WC Physics, Condensed Matter SC Physics GA 295UG UT WOS:000085985800028 ER PT J AU Daniel, M Balasubramanian, M Brewe, D Mehl, MJ Pease, D Budnick, JI AF Daniel, M Balasubramanian, M Brewe, D Mehl, MJ Pease, D Budnick, JI TI Site selectivity and bonding in the beta-phase aluminides: Studies of RuAl, PdAl, and Pd and Ru dopants in NiAl SO PHYSICAL REVIEW B LA English DT Article ID ABSORPTION FINE-STRUCTURE; DEBYE-WALLER FACTORS; TRANSITION-METAL ALUMINIDES; TEMPERATURE-DEPENDENCE; FEAL; ALLOYS; COAL; BULK AB We have determined the site selectivity of Ru and Pd dopants in beta-phase NiAl. For both transition metal rich and poor compositions, the Ru or Pd dopant goes to the Ni sublattice. The local structural disorder introduced by Pd dopants is significantly greater for the Al-rich than for the TM-rich composition. We have also determined the temperature dependence of the x-ray absorption fine structure Debye-Waller term for Ru atoms in stoichiometric RuAl, Ru in NiAl, and Pd in NiAl. We find evidence for large local shear resistance for Ru dopants in NiAl relative to Pd dopants in NiAl. These results are discussed in terms of calculated elastic moduli and cohesive energies of PdAl and RuAl. C1 Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. Univ Connecticut, Inst Mat Sci, Storrs, CT 06269 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11977 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. USN, Res Lab, Ctr Computat Mat Sci, Washington, DC 20375 USA. RP Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. RI Mehl, Michael/H-8814-2016 NR 39 TC 14 Z9 14 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 10 BP 6637 EP 6644 DI 10.1103/PhysRevB.61.6637 PG 8 WC Physics, Condensed Matter SC Physics GA 295UG UT WOS:000085985800029 ER PT J AU Lascialfari, A Jang, ZH Borsa, F Gatteschi, D Cornia, A Rovai, D Caneschi, A Carretta, P AF Lascialfari, A Jang, ZH Borsa, F Gatteschi, D Cornia, A Rovai, D Caneschi, A Carretta, P TI Magnetic and structural properties of an octanuclear Cu(II) S=1/2 mesoscopic ring: Susceptibility and NMR measurements SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-STRUCTURE; CRYSTAL-STRUCTURE; IRON(III) IONS; SPIN DYNAMICS; CLUSTERS; REACTIVITY; COMPLEXES; SPECTRA; H-1-NMR AB Magnetic susceptibility, H-1 NMR and Cu-63 NMR-NQR experiments on two slightly different species of the molecular S = 1/2 antiferromagnetic (AF) ring Cu8, [Cu-8(dmpz)(8)(OH)(8)].2C(5)H(5)N (Cu8P) and [Cu-8(dmpz)(8)(OH)(8)].2C(5)H(5)NO(2) (Cu8N), are presented. The magnetic energy levels are calculated exactly for an isotropic Heisenberg model Hamiltonian in zero magnetic field. From the magnetic susceptibility measurements we estimate the AF exchange coupling constant J similar to 1000 K and the resulting gap Delta similar to 500 K between the S-T = 0 ground state and the S-T = 1 first excited state. The Cu-63,Cu-65 NQR spectra indicate the presence of four crystallographically inequivalent copper nuclei in each ring. From the combination of the Cu-63 NQR spectra and of the Cu-63 NMR spectra at high magnetic field, we estimate the quadrupole coupling constant nu(Q) of each site and the average asymmetry parameter eta of the electric-field gradient tensor. The nuclear spin-lattice relaxation rate (NSLR) decreases exponentially on decreasing temperature for all nuclei investigated. The gap parameter extracted from Cu-63 NQR-NSLR is the same as for the susceptibility while a smaller value is obtained from the Cu-63 NMR-NSLR in an external magnetic field of 8.2 T. C1 Univ Pavia, Dept Phys A Volta, I-27100 Pavia, Italy. Univ Pavia, Unita INFM, I-27100 Pavia, Italy. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Univ Florence, Dept Chem, I-50144 Florence, Italy. Univ Modena, Dept Chem, I-41100 Modena, Italy. RP Univ Pavia, Dept Phys A Volta, Via Bassi 6, I-27100 Pavia, Italy. RI Gatteschi, Dante/B-5429-2008; Cornia, Andrea/N-8587-2015; OI Cornia, Andrea/0000-0001-9765-3128; Gatteschi, Dante/0000-0002-4859-4317; Caneschi, Andrea/0000-0001-5535-3469 NR 31 TC 20 Z9 20 U1 1 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 10 BP 6839 EP 6847 DI 10.1103/PhysRevB.61.6839 PG 9 WC Physics, Condensed Matter SC Physics GA 295UG UT WOS:000085985800057 ER PT J AU Balatsky, AV AF Balatsky, AV TI Field-induced d(x2-y2)+ id(xy) state and marginal stability of high-T-c superconductors SO PHYSICAL REVIEW B LA English DT Article ID D-WAVE SUPERCONDUCTORS; SYMMETRY ORDER PARAMETERS; SPONTANEOUS TIME-REVERSAL; D(X(2)-Y(2))-WAVE SUPERCONDUCTOR; THERMAL-CONDUCTIVITY; MAGNETIC-IMPURITIES; PAIRING SYMMETRY; PARITY BREAKING; SURFACE-STATES; J MODEL AB It is shown that the complex d(xy) component is generated in a d-wave superconductor in the magnetic field. As one enters a superconducting state at the finite field the normal to superconducting transition occurs into the bulk d(x2-y2) + id(xy) state. The driving force for the transition is the linear coupling between the magnetic field and the nonzero magnetization of the d(x2)-(y2) + id(xy) condensate. The external magnetic field violates parity and time-reversal symmetries and the nodal quasiparticle states respond by generating the id(xy) component of the order parameter, with the magnitude estimated to be on the order of a few kelvin. Parity (P) and time-reversal (T) symmetries are violated in this state. C1 Univ Calif Los Alamos Natl Lab, T Div, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, MST Div, Los Alamos, NM 87545 USA. RP Univ Calif Los Alamos Natl Lab, T Div, POB 1663, Los Alamos, NM 87545 USA. NR 44 TC 29 Z9 29 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 10 BP 6940 EP 6944 DI 10.1103/PhysRevB.61.6940 PG 5 WC Physics, Condensed Matter SC Physics GA 295UG UT WOS:000085985800070 ER PT J AU Hoffmann, A Prieto, P Schuller, IK AF Hoffmann, A Prieto, P Schuller, IK TI Periodic vortex pinning with magnetic and nonmagnetic dots: The influence of size SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; DYNAMIC PHASES; REGULAR ARRAY; PLASTIC-FLOW; THIN-FILMS; FLUX; VORTICES; LATTICES; DEFECTS; COMMENSURATE AB Periodic pinning arrays can give rise to commensurability effects for the vortex pinning in superconductors. We studied the influence of size and separation of the individual pinning centers made out of magnetic and nonmagnetic dots. While there is some dependence on the dot size, the periodic pinning changes its character drastically, as soon as the separation between dots becomes comparable to the coherence length of the superconductor. This can be understood by a crossover from a weak pinning regime to a superconducting wire network regime with decreasing dot separation. In addition, the comparison between the periodic pinning of magnetic dot arrays and nonmagnetic dot arrays shows that the former generally show more pronounced periodic pinning. This indicates conclusively a magnetic contribution to the pinning mechanism. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. RP Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RI Hoffmann, Axel/A-8152-2009 OI Hoffmann, Axel/0000-0002-1808-2767 NR 36 TC 113 Z9 113 U1 0 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 10 BP 6958 EP 6965 DI 10.1103/PhysRevB.61.6958 PG 8 WC Physics, Condensed Matter SC Physics GA 295UG UT WOS:000085985800072 ER PT J AU Haskel, D Stern, EA Dogan, F Moodenbaugh, AR AF Haskel, D Stern, EA Dogan, F Moodenbaugh, AR TI XAFS study of the low-temperature tetragonal phase of La2-xBaxCuO4: Disorder, stripes, and T-c suppression at x=0.125 SO PHYSICAL REVIEW B LA English DT Article ID ABSORPTION-FINE-STRUCTURE; MULTIPLE-SCATTERING CALCULATIONS; COPPER-OXIDE SUPERCONDUCTORS; MAGNETIC-ANOMALIES; LANTHANUM CUPRATE; TRANSITIONS; LA2-XSRXCUO4; ORDER; SPINS; HOLES AB Angular dependent x-ray absorption fine structure (XAFS);measurements of all La, Ba, and Cu sites determined the origin and nature of the intrinsic disorder present in the low temperature tetragonal (LTT) structural ground state of La2-xBaxCuO4 with x = 0.125,0.15 at T = 10 K. Ba doping induces major local distortions that extend as far as 5 Angstrom from its lattice site. Despite the low Ba content the large distortions significantly affect the XAFS of the majority La and Cu sites. The distribution of the local LTT tilt angle of CuO6 octahedra was directly determined from single and multiple scattering contributions to the XAFS of La and Cu sites. This angle, which regulates the strength of electron-lattice and spin-spin coupling in this material, was found to exhibit large, random fluctuations with rms [[(theta-[theta])(2)](1/2) approximate to 2 [theta], [theta] being the average tilt angle determined by diffraction techniques. These fluctuations originate in the large, random, static disorder introduced with Ba doping. Their presence has implications for the plausibility of a mobility gap causing T-c suppression at x = 0.125 in only the LTT phase, and for the correlation length of the postulated charge and spin stripes. 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 Argonne Natl Lab, Adv Photon Source, Bldg 401, Argonne, IL 60439 USA. OI Moodenbaugh, Arnold/0000-0002-3415-6762 NR 80 TC 47 Z9 47 U1 2 U2 12 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 10 BP 7055 EP 7076 DI 10.1103/PhysRevB.61.7055 PG 22 WC Physics, Condensed Matter SC Physics GA 295UG UT WOS:000085985800085 ER PT J AU Morr, DK Pines, D AF Morr, DK Pines, D TI Magnetic coherence in cuprate superconductors SO PHYSICAL REVIEW B LA English DT Article ID NEUTRON-SCATTERING; NORMAL-STATE; FLUCTUATIONS; LA2-XSRXCUO4; YBA2CU3O6.6; TEMPERATURE; DEPENDENCE AB Recent inelastic-neutron-scattering experiments on La2-xSrxCuO4 observed a magnetic coherence effect, i.e., strong frequency- and momentum-dependent changes of the spin susceptibility, chi", in the superconducting phase. We show that this effect is a direct consequence of changes in the damping of incommensurate antiferromagnetic spin fluctuations due to the appearance of a d-wave gap in the fermionic spectrum. Our theoretical results provide a quantitative explanation for the weak momentum dependence of the observed spin gap. Moreover, we predict (a) a Fermi surface in La2-xSrxCuO4 which is closed around (pi, pi) up to optimal doping and (b) similar changes in chi" for all cuprates with an incommensurate magnetic response. C1 Univ Illinois, Loomis Lab Phys, Urbana, IL 61801 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Inst Complex Adapt Matter, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, LANSCE Div, Los Alamos, NM 87545 USA. RP Univ Illinois, Loomis Lab Phys, 1110 W Green St, Urbana, IL 61801 USA. NR 18 TC 17 Z9 17 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2000 VL 61 IS 10 BP R6483 EP R6486 DI 10.1103/PhysRevB.61.R6483 PG 4 WC Physics, Condensed Matter SC Physics GA 295UG UT WOS:000085985800010 ER PT J AU Baker, FT Bimbot, L Edwards, G Glashausser, C Green, A Jones, KW Mihailidis, D Read, D Sethi, A Storm, BH deSwiniarski, R AF Baker, FT Bimbot, L Edwards, G Glashausser, C Green, A Jones, KW Mihailidis, D Read, D Sethi, A Storm, BH deSwiniarski, R TI Spin excitations in the Ca-40((p)over-right-arrow,(p)over-right-arrow ') reaction revisited SO PHYSICAL REVIEW C LA English DT Article ID MEV PROTONS; CA-40; RESONANCES; DELTA-S=0 AB Double differential cross sections d(2)sigma/d omega d Omega and spin-flip probabilities S-nn have been measured for the Ca-40((p) over right arrow,(p) over right arrow') reaction at E-p=319 MeV. The angular range of the experiment was 10.5 degrees less than or equal to theta(lab)less than or equal to 23 degrees and the range of excitation energies was 6 less than or equal to omega less than or equal to 47 MeV. These data and earlier data at smaller angles are compared to calculations employing random phase approximation nuclear structure and a distorted wave impulse approximation reaction model. C1 Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. Univ Paris Sud, Inst Phys Nucl, F-91406 Orsay, France. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08855 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Minnesota, Dept Phys, Minneapolis, MN 55455 USA. Univ Texas, Dept Phys, Austin, TX 78712 USA. IN2P3, CNRS, Inst Sci Nucl, F-38296 Grenoble, France. Univ Grenoble 1, F-38296 Grenoble, France. RP Baker, FT (reprint author), Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. NR 12 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 037302 PG 4 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500062 ER PT J AU Bender, M AF Bender, M TI alpha-decay chains of (289)(175)114 and (293)(175)118 in the relativistic mean-field model SO PHYSICAL REVIEW C LA English DT Article ID SUPERHEAVY NUCLEI; ELEMENTS AB A comparison of calculated and experimental Q(alpha) values of superheavy even-even nuclei and a few selected odd-N nuclei is presented in the framework of the relativistic mean-field model with the parametrization NL-Z2. Blocking effects are found to be important for a proper description of Q(alpha) of odd mass nuclei. The model gives a good overall description of the available experimental data. The mass and charge assignment of the recently measured decay chains from Dubna and Berkeley is in agreement with the predictions of the model. The analysis of the new data does not allow a final conclusion about the location of the expected island of spherical doubly magic superheavy nuclei. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. RP Bender, M (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RI Bender, Michael/B-9004-2009 NR 26 TC 73 Z9 74 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 MAR PY 2000 VL 61 IS 3 AR 031302 DI 10.1103/PhysRevC.61.031302 PG 4 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500002 ER PT J AU Bhatt, KH Kahane, S Raman, S AF Bhatt, KH Kahane, S Raman, S TI Collective properties of nucleons in the abnormal-parity states SO PHYSICAL REVIEW C LA English DT Article ID EVEN-EVEN NUCLEI; SHELL-MODEL DESCRIPTION; LOW-ENERGY STRUCTURE; DEFORMED-NUCLEI; HIGH SPINS; VALUES; BANDS AB In the first part of this work, we study the quadrupole collective properties of N-a = 2, 4, 6, and 8 nucleons occupying the abnormal-parity intruder single-particle states with high angular momenta j(a) = 9/2, 11/2, 13/2, and 15/2. This study is essential for a detailed understanding of the contribution made by these nucleons to the quadrupole collectivity of the yrast stares of deformed nuclei. The properties studied include (i) the distribution of the angular momenta J contained in the intrinsic state of N-a particles in the \j(a)k(a)] states, (ii) the relationship between the quadrupole moment Q(0)(j(a),N-a) of such an intrinsic state and the maximum angular momentum J(max) contained in it, (iii) the complete set of reduced quadrupole matrix elements (J'parallel to Q parallel to J) for transitions between all the states \J] and \J'] projected from the intrinsic state, (iv) the B(E2:J-->J-2) values, (v) the transition moments Q(t)(J), and (vi) the spectroscopic quadrupole moment Q(J). We compare these properties with similar properties of an intrinsic state having SU(3) symmetry which contains the same set of angular momenta as contained in the intrinsic state of a particular number of nucleons in a specific j(a) configuration. In the second part, we use the input from the first part to study the collective properties of the coupled system of protons and neutrons in abnormal-parity states. We show that the SU(3)-like features observed for the individual groups of abnormal-parity nucleons become stronger for the coupled system. Finally, in the third part, we consider the yrast bands of well-deformed nuclei projected from their Nilsson intrinsic states of valence nucleons in a major shell. We specify the structure of the wave function of each projected yrast state \J] in terms of the nucleons in both normal- and abnormal-parity states. These wave functions can be used to determine the individual contributions of the nucleons in normal- and abnormal-parity states to any specific property of the yrast state. In particular, we calculate the transition moments Q(t)(J) of the entire yrast band of even-even Yb160-166, Dy-156,Dy-158, Th-232, U-234, and U-236 projected from their respective Nilsson intrinsic states. C1 Univ Mississippi, Dept Phys & Astron, University, MS 38677 USA. Nucl Res Ctr, Beer Sheva, Israel. Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Bhatt, KH (reprint author), Univ Mississippi, Dept Phys & Astron, University, MS 38677 USA. NR 44 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 034317 PG 41 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500032 ER PT J AU Chiara, CJ Asztalos, SJ Busse, B Clark, RM Cromaz, M Deleplanque, MA Diamond, RM Fallon, P Fossan, DB Jenkins, DG Juutinen, S Kelsall, NS 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 Chiara, CJ Asztalos, SJ Busse, B Clark, RM Cromaz, M Deleplanque, MA Diamond, RM Fallon, P Fossan, DB Jenkins, DG Juutinen, S Kelsall, NS 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 Cd-109 SO PHYSICAL REVIEW C LA English DT Article ID MAGNETIC ROTATION; BANDS; STATES; LIFETIMES; PB-198; NUCLEI AB Lifetimes of high-spin states in two Delta I=1 bands and one Delta I=2 band in Cd-109 have been measured using the Doppler shift attenuation method in an experiment performed using the Zr-96(O-18,5n) reaction with the GAMMASPHERE array. Experimental total angular momenta and reduced transition strengths for both Delta I=1 bands were compared with tilted axis cranking (shears mechanism) predictions and the Delta I=2 band with principal axis cranking predictions, based on configurations involving two proton g(9/2) holes and one or three valence quasineutrons from the h(11/2) and mixed g(7/2)/d(5/2) orbitals. Good overall agreement for angular momentum versus rotational frequency has been observed in each case. The Delta I=2 band is shown to have a large J((2))/B(E2) ratio suggestive of antimagnetic rotation. Additionally, both dipole bands show a decreasing trend in B(M1) strength as a function of spin, a feature of the shears mechanism. The experimental results are also compared with a semiclassical model that employs effective interactions between the proton holes and neutrons as an alternate interpretation for the shears mechanism. C1 SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ York, Dept Phys, York YO1 5DD, N Yorkshire, England. Univ Jyvaskyla, Dept Phys, FIN-40351 Jyvaskyla, Finland. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. RP Chiara, CJ (reprint author), SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 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 31 TC 48 Z9 51 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 034318 DI 10.1103/PhysRevC.61.034318 PG 11 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500033 ER PT J AU Crowe, BJ Brune, CR Geist, WH Karwowski, HJ Ludwig, EJ Veal, KD Fonseca, AC Hale, GM Fletcher, KA AF Crowe, BJ Brune, CR Geist, WH Karwowski, HJ Ludwig, EJ Veal, KD Fonseca, AC Hale, GM Fletcher, KA TI Analyzing powers for H-2(d,d)H-2 at deuteron energies of 3.0, 4.75, and 6.0 MeV SO PHYSICAL REVIEW C LA English DT Article ID ELASTIC-SCATTERING; 3-NUCLEON; EQUATIONS; MODEL; SYSTEMS AB Tensor analyzing powers for H-2((d) over right arrow,d)H-2 elastic scattering were measured at deuteron energies of 3.0, 4.75, and 6.0 MeV. The measured values are below 0.02 and increase with increasing energy. The data were compared to the results of an R-matrix parametrization and microscopic four-body calculations. The calculations indicate that the nucleon-nucleon p waves have a strong effect on the observables. C1 Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Triangle Univ Nucl Lab, Durham, NC 27708 USA. Univ Lisbon, Ctr Fis Nucl, P-1699 Lisbon, Portugal. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. SUNY Geneseo, Dept Phys & Astron, Geneseo, NY 14454 USA. RP Crowe, BJ (reprint author), Shaw Univ, Raleigh, NC 27601 USA. RI Sa Fonseca, Antonio Carlos/M-3434-2013 OI Sa Fonseca, Antonio Carlos/0000-0002-5289-1162 NR 27 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 034006 DI 10.1103/PhysRevC.61.034006 PG 6 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500014 ER PT J AU Doring, J Akovali, YA Baktash, C Durham, FE Gross, CJ Hua, PF Johns, GD Korolija, M LaFosse, DR Lee, IY Macchiavelli, AO Rathbun, W Sarantites, DG Stracener, DW Solomon, GZ Tabor, SL Vander Molen, A Afanasjev, AV Ragnarsson, I AF Doring, J Akovali, YA Baktash, C Durham, FE Gross, CJ Hua, PF Johns, GD Korolija, M LaFosse, DR Lee, IY Macchiavelli, AO Rathbun, W Sarantites, DG Stracener, DW Solomon, GZ Tabor, SL Vander Molen, A Afanasjev, AV Ragnarsson, I TI Band terminations in the valence space of Zr-86 SO PHYSICAL REVIEW C LA English DT Article ID ROTATIONAL BANDS; HIGH-SPIN; SMOOTH TERMINATION; COLLECTIVITY; STATES; NUCLEI AB High-spin states in Zr-86 up to 30(+) and 27(-) were observed via the Ni-58(S-32,4p) reaction at 135 MeV beam energy using the combined GAMMASPHERE and MICROBALL systems. Calculations performed with the configuration-dependent shell-correction approach show that these states are built from six g(9/2) neutrons and at most four protons excited from the P-1/2,P-3/2,f(5/2) subshells to the g(9/2) subshell at small deformation. The highest observed states at 27(-) and 30(+) are interpreted as band-terminating states with the latter having the highest spin available in the valence space for Zr-86. C1 Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. Gesell Schwerionenforsch mbH, D-64291 Darmstadt, Germany. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Tulane Univ, Dept Phys, New Orleans, LA 70118 USA. Oak Ridge Inst Sci & Educ, UNISOR, Oak Ridge, TN 37831 USA. Washington Univ, Dept Chem, St Louis, MO 63130 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Lund Inst Technol, Dept Math Phys, S-21100 Lund, Sweden. Latvian Acad Sci, Nucl Res Ctr, LV-2169 Salaspils, Latvia. RP Doring, J (reprint author), Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. NR 23 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 034310 PG 6 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500025 ER PT J AU Engel, J Friar, JL Hayes, AC AF Engel, J Friar, JL Hayes, AC TI Nuclear octupole correlations and the enhancement of atomic time-reversal violation SO PHYSICAL REVIEW C LA English DT Article ID ODD ELECTROMAGNETIC MOMENTS; T-ODD; P-ODD; DEFORMATIONS; FORCES AB We examine the time-reversal-violating nuclear "Schiff moment" that induces electric dipole moments in atoms. After presenting a self-contained derivation of the form of the Schiff operator, we show that the distribution of Schiff strength, an important ingredient in the ground-state Schiff moment, is very different from the electric-dipole-strength distribution, with the Schiff moment receiving no strength from the giant dipole resonance in the Goldhaber-Teller model. We then present shell-model calculations in light nuclei that confirm the negligible role of the dipole resonance and show the Schiff strength to be strongly correlated with low-lying octupole strength. Next, we turn to heavy nuclei, examining recent arguments for the strong enhancement of Schiff moments in octupole-deformed nuclei over that of Hg-199, for example. We concur that there is a significant enhancement while pointing to effects neglected in previous work (both in the octupole-deformed nuclides and Hg-199) that may reduce it somewhat, and emphasizing the need for microscopic calculations to resolve the issue. Finally, we show that static octupole deformation is not essential for the development of collective Schiff moments; nuclei with strong octupole vibrations have them as well, and some could be exploited by experiment. C1 Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Engel, J (reprint author), Univ N Carolina, Dept Phys & Astron, CB3255, Chapel Hill, NC 27599 USA. NR 37 TC 47 Z9 48 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 MAR PY 2000 VL 61 IS 3 AR 035502 DI 10.1103/PhysRevC.61.035502 PG 13 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500059 ER PT J AU Forest, JL AF Forest, JL TI Effects of nonlocal one-pion-exchange potential in the deuteron SO PHYSICAL REVIEW C LA English DT Article ID RELATIVISTIC CORRECTIONS; CHARGE; RETARDATION; SCATTERING; DYNAMICS AB The off-shell aspects of the one-pion-exchange potential (OPEP) are discussed. Relativistic Hamiltonians containing relativistic kinetic energy, relativistic OPEP with various off-shell behaviors, and Argonne upsilon(18) short-range parametrization are used to study the deuteron wave functions. The OPEP off-shell behaviors depend on whether a pseudovector or pseudoscalar pion-nucleon coupling is used and are characterized by a parameter mu. We study potentials having mu= -1, 0, and +1 and we find that they are nearly unitarily equivalent. We also find that a nonrelativistic Hamiltonian containing local potentials and nonrelativistic kinetic energy provides a good approximation to a Hamiltonian containing a relativistic OPEP based on pseudovector pion-nucleon coupling and relativistic kinetic energy. C1 Jefferson Lab Theory Grp, Newport News, VA 23606 USA. RP Forest, JL (reprint author), Jefferson Lab Theory Grp, 12000 Jefferson Ave, Newport News, VA 23606 USA. EM jforest@jlab.org NR 22 TC 23 Z9 23 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 MAR PY 2000 VL 61 IS 3 AR 034007 DI 10.1103/PhysRevC.61.034007 PG 9 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500015 ER PT J AU Kruppa, AT Bender, M Nazarewicz, W Reinhard, PG Vertse, T Cwiok, S AF Kruppa, AT Bender, M Nazarewicz, W Reinhard, PG Vertse, T Cwiok, S TI Shell corrections of superheavy nuclei in self-consistent calculations SO PHYSICAL REVIEW C LA English DT Article ID MEAN-FIELD-THEORY; GROUND-STATE PROPERTIES; MULTIDIMENSIONAL DEFORMATION SPACE; DENSITY-FUNCTIONAL-APPROACH; FISSION-BARRIERS; EFFECTIVE FORCES; PSEUDOSPIN SYMMETRY; POTENTIAL-ENERGY; LEVEL DENSITY; DRIP-LINE AB Shell corrections to the nuclear binding energy as a measure of shell effects in superheavy nuclei are studied within the self-consistent Skyrme-Hartree-Fock and relativistic mean-field theories. As a result of the presence of a low-lying proton continuum resulting in a free particle gas, special attention is paid to the treatment of the single-particle level density. To cure the pathological behavior of the shell correction around the particle threshold, a method based on the Green's function approach has been adopted. It is demonstrated that for the vast majority of Skyrme interactions commonly employed in nuclear structure calculations, the strongest shell stabilization appears for Z = 124 and 126, and for N = 184. On the other hand, in the relativistic approaches the strongest spherical shell effect appears systematically for Z = 120 and N = 172. This difference probably has its roots in the spin-orbit potential. We have also shown that, in contrast to shell corrections which are fairly independent of the force, macroscopic energies extracted from self-consistent calculations strongly depend on the actual force parametrization used. That is, the A and Z dependence of the mass surface when extrapolating to unknown superheavy nuclei is prone to significant theoretical uncertainties. C1 Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. Hungarian Acad Sci, Inst Nucl Res, H-4001 Debrecen, Hungary. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Warsaw, Inst Theoret Phys, PL-00681 Warsaw, Poland. Univ Erlangen Nurnberg, Inst Theoret Phys 2, D-91058 Erlangen, Germany. Warsaw Univ Technol, Fac Phys, PL-00662 Warsaw, Poland. RP Kruppa, AT (reprint author), Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, POB 2008, Oak Ridge, TN 37831 USA. RI Bender, Michael/B-9004-2009 NR 89 TC 164 Z9 168 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 034313 DI 10.1103/PhysRevC.61.034313 PG 13 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500028 ER PT J AU Mashnik, SG Peterson, RJ Sierk, AJ Braunstein, MR AF Mashnik, SG Peterson, RJ Sierk, AJ Braunstein, MR TI Pion-induced transport of pi mesons in nuclei SO PHYSICAL REVIEW C LA English DT Article ID CASCADE-EXCITON MODEL; CHARGE-EXCHANGE; ABSORPTION; PROTONS; SCATTERING; CARBON AB A large body of data for pion-induced neutral pion continuum spectra spanning outgoing energies near 180 MeV shows no dip there that might be ascribed to internal strong absorption processes involving the formation of Delta's. This is the same observation previously made for the charged pion continuum spectra. Calculations in an intranuclear cascade model or a cascade exciton model with free-space parameters predict such a dip for both neutral and charged pions. We explore several medium modifications to the interactions of pions with internal nucleons that are able to reproduce the data for nuclei from Li-7 through Bi. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Colorado, Phys Nucl Lab, Boulder, CO 80309 USA. Cent Washington Univ, Dept Phys, Ellensburg, WA 98926 USA. RP Mashnik, SG (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, T-2, Los Alamos, NM 87545 USA. EM mashnik@t2y.lanl.gov NR 48 TC 11 Z9 11 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 034601 DI 10.1103/PhysRevC.61.034601 PG 13 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500034 ER PT J AU McNabb, DP Cizewski, JA Khoo, TL Lauritsen, T Hauschild, K Ding, KY Fotiades, N Younes, W Archer, DE Bauer, RW Becker, JA Bernstein, LA Clark, RM Deleplanque, MA Diamond, RM Fallon, P Lee, IY Macchiavelli, AO MacLeod, RW Stephens, FS Lopez-Martens, A Kelly, WH AF McNabb, DP Cizewski, JA Khoo, TL Lauritsen, T Hauschild, K Ding, KY Fotiades, N Younes, W Archer, DE Bauer, RW Becker, JA Bernstein, LA Clark, RM Deleplanque, MA Diamond, RM Fallon, P Lee, IY Macchiavelli, AO MacLeod, RW Stephens, FS Lopez-Martens, A Kelly, WH TI Quasicontinuous decay spectra of superdeformed bands in Pb-192,Pb-194 and energy gaps in level density at moderate angular momenta SO PHYSICAL REVIEW C LA English DT Article ID GAMMA-RAYS; PB-194; STATES; HG-192 AB The quasicontinuous spectra associated with the decay of the superdeformed bands in Pb-192,Pb-194 have been extracted. The rapid rise in the gamma-ray intensity in these spectra for E gamma less than or similar to 1.8 MeV is interpreted to arise from the dramatic increase in level density above the energy gap for even-even nuclei. This energy gap has been found to be approximate to 0.95(10) MeV at 6 (h) over bar in Pb-194 and approximate to 0.41(-0.1)(+0.4) MeV at 10 (h) over bar in Pb-192. C1 Rutgers State Univ, Dept Phys & Astron, New Brunswick, NJ 08903 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Inst Rech Subatom, F-67037 Strasbourg, France. Iowa State Univ, Ames, IA 50011 USA. RP McNabb, DP (reprint author), Rutgers State Univ, Dept Phys & Astron, New Brunswick, NJ 08903 USA. RI Hauschild, Karl/A-6726-2009 NR 20 TC 12 Z9 12 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 031304 DI 10.1103/PhysRevC.61.031304 PG 5 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500004 ER PT J AU Nicoli, MP Haas, F Freeman, RM Szilner, S Basrak, Z Morsad, A Satchler, GR Brandan, ME AF Nicoli, MP Haas, F Freeman, RM Szilner, S Basrak, Z Morsad, A Satchler, GR Brandan, ME TI Detailed study and mean field interpretation of O-16+C-12 elastic scattering at seven medium energies SO PHYSICAL REVIEW C LA English DT Article ID C-12+C-12 SCATTERING; NUCLEAR-MATTER AB Detailed measurements of the elastic scattering of O-16 ions from C-12 have been carried out at seven energies from 62 to 124 MeV, at center-of-mass angles from about 10 degrees to about 145 degrees. A coherent optical model analysis of these data has been performed using both the Woods-Saxon and the folding-model potentials. The extracted results are consistent with analyses of data at higher energies for this and similar light heavy-ion systems. Some model-independent spline forms for the real potentials were also investigated. C1 Inst Rech Subatom, IN2P3, CNRS, UMR 7500, F-67037 Strasbourg 2, France. Univ Strasbourg 1, F-67037 Strasbourg, France. Rudjer Boskovic Inst, Zagreb, Croatia. Univ Hassan II, Fac Sci Ben Msik, Casablanca, Morocco. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Nacl Autonoma Mexico, Inst Fis, Mexico City 01000, DF, Mexico. RP Nicoli, MP (reprint author), Inst Rech Subatom, IN2P3, CNRS, UMR 7500, BP28, F-67037 Strasbourg 2, France. RI Brandan, Maria-Ester/K-9014-2012 OI Brandan, Maria-Ester/0000-0002-1165-3440 NR 23 TC 40 Z9 40 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 MAR PY 2000 VL 61 IS 3 AR 034609 DI 10.1103/PhysRevC.61.034609 PG 8 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500042 ER PT J AU Starosta, K Chiara, CJ Fossan, DB Koike, T LaFosse, DR Lane, GJ Sears, JM Smith, JF Boston, AJ Nolan, PJ Paul, ES Semple, AT Devlin, M Sarantites, DG Lee, IY Macchiavelli, AO AF Starosta, K Chiara, CJ Fossan, DB Koike, T LaFosse, DR Lane, GJ Sears, JM Smith, JF Boston, AJ Nolan, PJ Paul, ES Semple, AT Devlin, M Sarantites, DG Lee, IY Macchiavelli, AO TI gamma-ray spectroscopy in Te-111 SO PHYSICAL REVIEW C LA English DT Article ID OCTUPOLE CORRELATIONS; INTRUDER BANDS; NUCLEI; SPIN; STATES; ISOTOPES; MOMENTS AB Excited states in Te-111 have been studied using the 4pn evaporation channel from the Ni-58 + Ni-58 reaction at a beam energy of 250 MeV. A thin-target experiment was carried out using GAMMASPHERE coupled with the MICROBALL charged-particle detector array and an array of neutron detectors. A complementary thick-target experiment was performed with the Stony Brook six-Ge-detector array in order to measure the lifetime of an 11/2(-) isomer observed in the GAMMASPHERE data. The structure of Te-111 at low spin is dominated by the yrast nu (h) over bar(11/2) band, although a band assigned to the nu(g(7/2)d(5/2)) configuration is also observed. Four collective bands have been found at higher spins. Experimental results are compared to the odd-A Te systematics and to core-quasiparticle and total Routhian surface calculations. C1 SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Univ Liverpool, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. Washington Univ, Dept Chem, St Louis, MO 63130 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Starosta, K (reprint author), SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. RI Lane, Gregory/A-7570-2011; Devlin, Matthew/B-5089-2013 OI Lane, Gregory/0000-0003-2244-182X; Devlin, Matthew/0000-0002-6948-2154 NR 40 TC 12 Z9 12 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 034308 DI 10.1103/PhysRevC.61.034308 PG 13 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500023 ER PT J AU Tzeng, YH Tzeng, SYT Kuo, TTS Lee, TSH Stoks, VGD AF Tzeng, YH Tzeng, SYT Kuo, TTS Lee, TSH Stoks, VGD TI Two-frequency shell model for hypernuclei and meson-exchange hyperon-nucleon potentials SO PHYSICAL REVIEW C LA English DT Article ID PI(+),K+ REACTION; ENERGIES AB A two-frequency shell model is proposed for investigating;the structure of hypernuclei starting with a hyperon-nucleon potential in free space. In a calculation-using the folded-diagram method for O-16(Lambda), the Lambda single particle energy is found to have a saturation minimum at an oscillator frequency (h) over bar omega(Lambda) approximate to 10 MeV, for the Lambda orbit, which is considerably smaller than (h) over bar omega(N) = 14 MeV for the nucleon orbit. The spin-dependence parameters derived from the Nijmegen NSC89 and NSC97f potentials :are;similar, but both are rather different from those obtained with the Julich-B potential. The Lambda NN three-body :interactions induced by Lambda N-Sigma N transitions are important for the spin parameters, but relatively unimportant for the low-lying states of O-16(Lambda). C1 Acad Sinica, Inst Phys, Taipei, Taiwan. Natl Taipei Univ Technol, Taipei, Taiwan. SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Adelaide, Ctr Subatom Struct Matter, Adelaide, SA 5005, Australia. RP Tzeng, YH (reprint author), Acad Sinica, Inst Phys, Taipei, Taiwan. NR 28 TC 2 Z9 2 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 EI 1089-490X J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 031305 DI 10.1103/PhysRevC.61.031305 PG 4 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500005 ER PT J AU Vogt, R AF Vogt, R TI x(F) dependence of psi and Drell-Yan production SO PHYSICAL REVIEW C LA English DT Article ID RADIATIVE ENERGY-LOSS; NUCLEUS-NUCLEUS COLLISIONS; QUARK-GLUON PLASMA; PB-PB INTERACTIONS; INTRINSIC CHARM; PARTON DISTRIBUTIONS; HADRONIC COLLISIONS; J/PSI-PRODUCTION; HEAVY QUARKS; DIMUON PRODUCTION AB We discuss the nuclear dependence of psi and psi' production,in hadron-nucleus interactions as a function of longitudinal momentum fraction x(F). Nuclear effects such as final-state absorption, interactions with comovers, shadowing of parton distributions, energy loss, and intrinsic heavy-quark components are described separately and incorporated into the model which is then compared to the preliminary E866 data. The resulting nuclear dependence of Drell-Yan production at 800 GeV and proposed measurements of psi, psi', and Drell-Yan production at 120 GeV are also calculated. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 94 TC 74 Z9 75 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 035203 DI 10.1103/PhysRevC.61.035203 PG 23 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500054 ER PT J AU White, JA Koonin, SE Dean, DJ AF White, JA Koonin, SE Dean, DJ TI Shell model Monte Carlo investigation of rare earth nuclei SO PHYSICAL REVIEW C LA English DT Article ID STATIC-PATH APPROXIMATION; LEVEL DENSITIES; DY-154 AB We utilize the shell model Monte Carlo method to study the structure of rare earth nuclei. This work demonstrates the first systematic full oscillator shell with intruder calculations in such heavy nuclei. Exact solutions of a pairing plus quadrupole Hamiltonian are compared with the static path approximation in several dysprosium isotopes from A = 152 to 162, including the odd mass A = 153. Some comparisons are also made with Hartree-Fock-Bogoliubov results from Baranger and Kumar. Basic properties of these nuclei at various temperatures and spin are explored. These include energy, deformation, moments of inertia, pairing channel strengths, band crossing, and evolution of shell model occupation numbers. Exact level densities are also calculated and, in the case of Dy-162, compared with experimental data. C1 CALTECH, WK Kellogg Radiat Lab, Pasadena, CA 91125 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RP White, JA (reprint author), CALTECH, WK Kellogg Radiat Lab, 106-38, Pasadena, CA 91125 USA. NR 24 TC 33 Z9 34 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAR PY 2000 VL 61 IS 3 AR 034303 DI 10.1103/PhysRevC.61.034303 PG 15 WC Physics, Nuclear SC Physics GA 292KE UT WOS:000085792500018 ER PT J AU Altes, CPK Pisarski, RD Sinkovics, A AF Altes, CPK Pisarski, RD Sinkovics, A TI Potential for the phase of the Wilson line at nonzero quark density SO PHYSICAL REVIEW D LA English DT Article ID SU(3) GAUGE-THEORY; DECONFINED INTERFACE TENSION; ZETA-FUNCTION REGULARIZATION; HIGH-TEMPERATURE EXPANSIONS; GROUND-STATE ENERGY; FINITE-TEMPERATURE; QUANTUM CHROMODYNAMICS; VECTOR-MESONS; QUENCHED QCD; ORDER PARAMETER AB The contribution of quarks to the effective potential for the phase of the Wilson line is computed at nonzero temperature and quark chemical potential to one and two loop order. At zero temperature, regardless of the value of the quark chemical potential, the effective potential for the phase of the Wilson line vanishes. At nonzero temperature, for special values of the phase the free energy of quarks equals that of bosons; at nonzero chemical potential, such quarks can "Bose condense," albeit with negative density. C1 CNRS, Ctr Phys Theor, F-13288 Marseille, France. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. RP Altes, CPK (reprint author), CNRS, Ctr Phys Theor, Case 907, F-13288 Marseille, France. EM Chris.Korthal-Altes@cpt.univ-mrs.fr; pisarski@bnl.gov; ani@umich.edu NR 55 TC 23 Z9 23 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 MAR 1 PY 2000 VL 61 IS 5 AR 056007 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600053 ER PT J AU 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 Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Davis, R Kotov, S Kravchenko, I Kwak, N Zhao, X Zhou, L Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Alam, MS Athar, SB Mahmood, AH Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Glenn, S Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Csorna, SE McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, HN Nelson, TK Richman, JD 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, R 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 Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Ward, C AF 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 Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Davis, R Kotov, S Kravchenko, I Kwak, N Zhao, X Zhou, L Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Alam, MS Athar, SB Mahmood, AH Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Glenn, S Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Csorna, SE McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, HN Nelson, TK Richman, JD 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, R 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 Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Ward, C CA CLEO Collaboration TI Limit on the tau neutrino mass from tau(-)->pi(-)pi(+)pi(-)pi(0)nu(tau) SO PHYSICAL REVIEW D LA English DT Article ID DECAYS; LIBRARY; NUCLEOSYNTHESIS AB From a data sample of 29058 tau(+/-) --> pi(+/-) pi(+) pi(-) pi(0)nu(tau) decays observed in the CLEO detector we derive a 95% confidence upper limit on the tau neutrino mass of 28 MeV. C1 Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Hawaii Manoa, Honolulu, HI 96822 USA. Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Ottawa, ON, Canada. 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. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Colorado, Boulder, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Yonsei Univ, Seoul 120749, South Korea. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Texas, Austin, TX 78712 USA. RP Univ Florida, Gainesville, FL 32611 USA. RI Warburton, Andreas/N-8028-2013; Briere, Roy/N-7819-2014 OI Warburton, Andreas/0000-0002-2298-7315; Briere, Roy/0000-0001-5229-1039 NR 28 TC 3 Z9 3 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD MAR 1 PY 2000 VL 61 IS 5 AR 052002 DI 10.1103/PhysRevD.61.052002 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600005 ER PT J AU Atwood, D Bar-Shalom, S Soni, A AF Atwood, D Bar-Shalom, S Soni, A TI Gauge-boson-gauge-boson scattering in theories with large extra dimensions SO PHYSICAL REVIEW D LA English DT Article ID TEV; MILLIMETER; COLLISIONS AB We consider the scattering amplitudes of the form V1V2 --> V3V4 where V-i = gamma, Z, W or g(= gluon) are the standard model gauge bosons, due to graviton exchange in Kaluza-Klein theories with large extra dimensions. This leads to a number of experimentally viable signatures at high energy leptonic and hadronic colliders. We discuss the observability or attainable limits on the scale of the gravitational interactions (m(D)), that may be obtained at an e(+)e(-) Next Linear Collider (NLC) and at the CERN LHC, by studying some of these types of gauge-boson scattering processes. We find that the attainable limits through these type of processes are m(D)greater than or similar to 3 TeV at the NLC and m(D)greater than or similar to 6 TeV at the LHC. C1 Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. Brookhaven Natl Lab, Theory Grp, Upton, NY 11973 USA. RP Atwood, D (reprint author), Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. EM atwood@iastate.edu; shaouly@phyun0.ucr.edu; soni@bnl.gov NR 46 TC 15 Z9 15 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAR 1 PY 2000 VL 61 IS 5 AR 054003 DI 10.1103/PhysRevD.61.054003 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600017 ER PT J AU Barger, V Geer, S Whisnant, K AF Barger, V Geer, S Whisnant, K TI Long baseline neutrino physics with a muon storage ring neutrino source SO PHYSICAL REVIEW D LA English DT Review ID DOUBLE-BETA-DECAY; GEV ENERGY-RANGE; CP VIOLATION; OSCILLATION EXPERIMENTS; ATMOSPHERIC NEUTRINOS; PARAMETRIC-RESONANCE; MAJORANA NEUTRINOS; LSND EXPERIMENT; LEPTON SECTOR; MASS-SPECTRUM AB We examine the physics capabilities of known flavor neutrino beams from intense muon sources. We find that long-baseline neutrino experiments based on such beams can provide precise measurements of neutrino oscillation mass and mixing parameters. Furthermore, they can test whether the dominant atmospheric neutrino oscillations are nu(mu) --> nu(tau) and/or nu(mu) --> nu(s), determine the nu(mu) --> nu(e) content of atmospheric neutrino oscillations, and measure nu(e) --> nu(tau) appearance. Depending on the oscillation parameters, they may be able to detect Earth matter and CP violation effects and to determine the ordering of some of the mass eigenstates. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. NR 117 TC 97 Z9 97 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 MAR 1 PY 2000 VL 61 IS 5 AR 053004 DI 10.1103/PhysRevD.61.053004 PG 19 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600011 ER PT J AU 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 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 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 Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J 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 Zhao, X Zhou, L Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Alam, MS Athar, SB Mahmood, AH Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Glenn, S Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Csorna, SE McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, HN Nelson, TK Richman, JD Roberts, D AF 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 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 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 Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J 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 Zhao, X Zhou, L Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Alam, MS Athar, SB Mahmood, AH Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Glenn, S Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Csorna, SE McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, HN Nelson, TK Richman, JD Roberts, D CA CLEO Collaboration TI Measurement of B ->rho l nu decay and vertical bar V-ub vertical bar SO PHYSICAL REVIEW D LA English DT Article ID FORM-FACTOR RELATIONS; SEMI-LEPTONIC DECAYS; SEMILEPTONIC DECAYS; QUARK-MODEL; MESON DECAYS; SUM-RULES; B-DECAYS; HEAVY; TRANSITIONS; LATTICE AB Using a sample of 3.3 X 10(6) Y (4S) --> B (B) over bar events collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR), we measure B(B --> rho l nu), \V-ub\, and the partial rate (Delta Gamma) in three bins of q(2) = (p(B) - p(rho))(2). We find B(B-0 --> rho (-)l(+) nu) = (2.69+/-0.4(-0.40)(+0.35)+/-0.50) X 10(-4), \V-ub\ = (3 23+/-0.24(-0.26)(+0.23)+/-0.58) X 10(-3), Delta Gamma(0 < q(2) < 7 GeV2/c(4)) = (7.6+/-3.0(-1.2)(+0.9)+/-3.0) X 10(-2) ns(-1), Delta Gamma(7 < q(2) < 14 GeV2/c(4)) = (4.8+/-2.9(-0.8)(+0.7)+/-0.7) X 10(-2) ns(-1), and Delta Gamma(14 < q(2) < 21 GeV2/c(4)) = (7.1+/-2.1(-1.1)(+0.9)+/-0.6) X 10(-2) ns(-1). Here, l = e or mu, but not both, and the errors are statistical, systematic, and theoretical. The method is sensitive primarily to B --> rho l nu decays with leptons in the energy range above 2.3 GeV. Averaging with the previously published CLEO results for B --> rho l nu, we obtain B(B-0 --> rho(-)l(+) nu) = (2.57+/-0.29(-0.46)(+0.33)+/-0.41) X 10(-4) and \V-ub\ = (3.25+/-0.14(-0.29)(+0.21)+/-0.55) X 10(-3). C1 Univ Colorado, Boulder, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Illinois, Urbana, IL 61801 USA. Univ Hawaii Manoa, Honolulu, HI 96822 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Ottawa, ON, Canada. McGill Univ, Montreal, PQ H3A 2T8, Canada. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oklahoma, Norman, OK 73019 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Texas, Austin, TX 78712 USA. Yonsei Univ, Seoul 120749, South Korea. Univ Cincinnati, Cincinnati, OH 45221 USA. RP Behrens, BH (reprint author), Univ Colorado, Boulder, CO 80309 USA. RI Warburton, Andreas/N-8028-2013; Briere, Roy/N-7819-2014 OI Warburton, Andreas/0000-0002-2298-7315; Briere, Roy/0000-0001-5229-1039 NR 34 TC 66 Z9 66 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAR 1 PY 2000 VL 61 IS 5 AR 052001 DI 10.1103/PhysRevD.61.052001 PG 19 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600004 ER PT J AU Bergmann, S Grossman, Y Pierce, DM AF Bergmann, S Grossman, Y Pierce, DM TI Can lepton flavor violating interactions explain the atmospheric neutrino problem? SO PHYSICAL REVIEW D LA English DT Article ID W-BOSON MASS; HOT DARK-MATTER; SUPERSYMMETRIC MODELS; ELECTROWEAK PARAMETERS; PRECISION-MEASUREMENT; NUMBER VIOLATION; ATOMIC THALLIUM; LSND EXPERIMENT; R-PARITY; SOLAR AB We investigate whether flavor changing neutrino interactions (FCNIs) can be sufficiently large to provide a viable solution to the atmospheric neutrino problem. Effective operators induced by heavy boson exchange that allow for flavor changing neutrino scattering off quarks or electrons are related by an SU(2)(L) rotation to operators that induce anomalous tau decays. Since SU(2)(L) violation is small for new physics at or above the weak scale, one can use the upper bounds on lepton flavor violating tau decays or on lepton universality violation to put severe, model-independent bounds on the relevant non-standard neutrino interactions. Also Z-induced flavor changing neutral currents, due to heavy singlet neutrinos, are too small to be relevant for the atmospheric neutrino anomaly. We conclude that the FCNI solution to the atmospheric neutrino problem is ruled out. C1 Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Bergmann, S (reprint author), Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. OI Bergmann, Sven/0000-0002-6785-9034 NR 91 TC 59 Z9 59 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 MAR 1 PY 2000 VL 61 IS 5 AR 053005 DI 10.1103/PhysRevD.61.053005 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600012 ER PT J AU Brisudova, MM Burakovsky, L Goldman, T AF Brisudova, MM Burakovsky, L Goldman, T TI Effective functional form of Regge trajectories SO PHYSICAL REVIEW D LA English DT Article ID TRANSVERSE-MOMENTUM DEPENDENCE; TOTAL CROSS-SECTIONS; B-C-MESON; P-INTERACTIONS; FEYNMAN-X; D(0),(D)OVER-BAR(0) PRODUCTION; P(P)OVER-BAR COLLISIONS; NUCLEON-INTERACTIONS; ROOT-S=1.8 TEV; MASS RELATIONS AB We present theoretical arguments and strong phenomenological evidence that hadronic Regge trajectories are essentially nonlinear and can be well approximated, for phenomenological purposes, by a specific square-root form. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Theoret, MS B283, Los Alamos, NM 87545 USA. EM brisuda@t5.lanl.gov; burakov@t5.lanl.gov; goldman@t5.lanl.gov NR 93 TC 63 Z9 63 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD MAR 1 PY 2000 VL 61 IS 5 AR 054013 DI 10.1103/PhysRevD.61.054013 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600027 ER PT J AU Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Davis, R Kotov, S Kravchenko, I Kwak, N Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Mahmood, AH Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Wolf, A Wu, J Csorna, SE MacLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, TK Richman, JD Briere, RA Behrens, BH Ford, WT Gritsan, A Krieg, H Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lee, T Liu, Y Meyer, TO Mistry, NB Ng, CR Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Avery, P Lohner, M Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R AF Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Davis, R Kotov, S Kravchenko, I Kwak, N Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Mahmood, AH Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Wolf, A Wu, J Csorna, SE MacLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, TK Richman, JD Briere, RA Behrens, BH Ford, WT Gritsan, A Krieg, H Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lee, T Liu, Y Meyer, TO Mistry, NB Ng, CR Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Avery, P Lohner, M Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R CA CLEO Collaboration TI Structure functions in the decay tau(-/+)->pi(-/+)pi(0)pi(0)nu(tau) SO PHYSICAL REVIEW D LA English DT Article ID TAU-DECAYS; TAU->3-PI-NU(TAU) AB Using the CLEO II detector operating at the Cornell Electron Storage Ring (CESR) e(+) e(-) collider, we have measured the structure functions in the decay tau(-/+) --> pi(-/+) pi(0)pi(0)nu(tau), based on a sample corresponding to 4 X 10(6) produced tau-pair events. We determine the integrated structure functions, which depend only on the three pion invariant mass, as well as the structure functions differential in the Dalitz plot variables. We extract model independent limits on non-axial-vector contributions from the measured structure functions as less than 16.6% of thr total branching fraction, at the 95% confidence level. Separating the non-axial-vector contributions into scalar and vector contributions, we measure that scalers (vectors) contribute;with less than 9.4% (7.3%) to the total branching fraction, at the 95% confidence level. C1 Univ Hawaii Manoa, Honolulu, HI 96822 USA. Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Ottawa, ON, Canada. McGill Univ, Montreal, PQ H3A 2T8, Canada. Ithaca Coll, Ithaca, NY 14850 USA. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oklahoma, Norman, OK 73019 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Colorado, Boulder, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Texas Pan Amer, Edinburg, TX 78539 USA. Yonsei Univ, Seoul 120749, South Korea. Univ Cincinnati, Cincinnati, OH 45221 USA. RP Browder, TE (reprint author), Univ Hawaii Manoa, Honolulu, HI 96822 USA. RI Warburton, Andreas/N-8028-2013; Briere, Roy/N-7819-2014 OI Warburton, Andreas/0000-0002-2298-7315; Briere, Roy/0000-0001-5229-1039 NR 14 TC 20 Z9 20 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAR 1 PY 2000 VL 61 IS 5 AR 052004 DI 10.1103/PhysRevD.61.052004 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600007 ER PT J AU Chang, CHV Chang, D Keung, WY AF Chang, CHV Chang, D Keung, WY TI Vector quark model and B -> X-s gamma decay SO PHYSICAL REVIEW D LA English DT Article ID CHANGING NEUTRAL CURRENTS; B-DECAY; LEADING LOGARITHMS; CP ASYMMETRIES; WEAK DECAYS; B->X(S)GAMMA; B->S-GAMMA; UNCERTAINTIES; SINGLET; BOUNDS AB We study the B meson radiative decay B --> X(s)gamma in the vector quark model. Deviation from the standard model arises from the nonunitarity of the charged current Kobayashi-Maskawa matrix and related new flavor changing neutral current interactions. We establish the relation between the nonunitarity of the charged current mixing matrix and the mixing among the vector quark and ordinary quarks. We also explicitly make the close connection between this nonunitarity and the flavor changing neutral currents. The complete calculation including the leading logarithmic QCD correction is carefully carried out. Using the most updated data and the next to leading order theoretical calculation, the branching fraction of the observed B meson radiative decay places a limit on the mixing angles as stringent as that from the process B --> X mu<(mu)over bar>. C1 Natl Tsing Hua Univ, NCTS, Hsinchu 30043, Taiwan. Natl Tsing Hua Univ, Dept Phys, Hsinchu 30043, Taiwan. Natl Taiwan Normal Univ, Dept Phys, Taipei 117, Taiwan. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. RP Chang, CHV (reprint author), Natl Tsing Hua Univ, NCTS, Hsinchu 30043, Taiwan. NR 29 TC 19 Z9 19 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 MAR 1 PY 2000 VL 61 IS 5 AR 053007 DI 10.1103/PhysRevD.61.053007 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600014 ER PT J AU Chou, CL Peskin, ME AF Chou, CL Peskin, ME TI Scalar top quark as the next-to-lightest supersymmetric particle SO PHYSICAL REVIEW D LA English DT Article ID FERMILAB TEVATRON; BREAKING MODELS; STANDARD-MODEL; ENERGY; POLARIZATION; GRAVITINO; COLLIDERS; PHYSICS; SEARCH; SQUARK AB We study phenomenologically the scenario in which the scalar top quark is lighter than any other standard supersymmetric partner and also lighter than the top quark, so that it decays to the gravitino via (t) over tilde --> W(+)b (G) over tilde. In this case, scalar top quark events would seem to be Very difficult to separate from top quark pair production. However, we show that, even at a hadron collider, it is possible to distinguish these two reactions. We show also that the longitudinal polarization of the final W+ gives insight into the scalar top quark and W-ino-Higgsino mixing parameters. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Chou, CL (reprint author), Acad Sinica, Inst Phys, Taipei 11529, Taiwan. NR 21 TC 26 Z9 26 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAR 1 PY 2000 VL 61 IS 5 AR 055004 DI 10.1103/PhysRevD.61.055004 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600039 ER PT J AU Geiger, K Ellis, J Heinz, U Wiedemann, UA AF Geiger, K Ellis, J Heinz, U Wiedemann, UA TI Bose-Einstein correlations in a space-time approach to e(+)e(-) annihilation into hadrons SO PHYSICAL REVIEW D LA English DT Article ID HEAVY-ION COLLISIONS; FINAL-STATE INTERACTIONS; MONTE-CARLO GENERATORS; HIGH-ENERGY COLLISIONS; QCD PHASE-TRANSITIONS; E+E ANNIHILATION; PION INTERFEROMETRY; CERN SPS; PARTON; COLOR AB A new treatment of Bose-Einstein correlations is incorporated in a space-time parton-shower model for e(+)e(-) annihilation into hadrons. Two alternative algorithms are discussed, and we use a simple calculable model to demonstrate that they reproduce successfully the size of the hadron emission region. One of the algorithms is used to calculate two-pion correlations in e(+)e(-) --> Z(0) --> hadrons and e(+)e(-) --> W+W- --> hadrons. Results are shown with and without resonance decays, for correlations along and transverse to the thrust jet axis in these two classes of events. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. CERN, Div Theoret Phys, CH-1211 Geneva 23, Switzerland. Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany. Columbia Univ, Dept Phys, New York, NY 10027 USA. EM John.Ellis@cern.ch; Ulrich.Heinz@cern.ch; awiedema@nt3.phys.columbia.edu NR 92 TC 17 Z9 17 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAR 1 PY 2000 VL 61 IS 5 AR 054002 DI 10.1103/PhysRevD.61.054002 PG 17 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600016 ER PT J AU Ichinose, S AF Ichinose, S TI Temperature in fermion systems and the chiral fermion determinant SO PHYSICAL REVIEW D LA English DT Article ID DOMAIN-WALL QUARKS; GAUGE-THEORIES; OVERLAP FORMULATION; LATTICE; ANOMALIES; QCD AB We give an interpretation to the issue of the chiral determinant in the heat-kernel approach. The extra dimension (fifth dimension) is interpreted as (inverse) temperature. The (1 +4)-dimensional Dirac equation is naturally derived by the Wick rotation for the temperature. In order to define a "good'' temperature, we choose those solutions of the Dirac equation which propagate in a fixed direction in the extra coordinate. This choice fixes the regularization of the fermion determinant. The (1+4)-dimensional Dirac mass (M) is naturally introduced and the relation \four-dimensional electron momentuml \ << \M\ << ultraviolet cutoff naturally appears. The chiral anomaly is explicitly derived for the two-dimensional Abelian model. Typically two different regularizations appear depending on the choice of propagators. One corresponds to the chiral theory, the other to the nonchiral (Hermitian) theory. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM ichinose@u-shizuoka-ken.ac.jp RI Ichinose, Shoichi/E-8277-2013 NR 28 TC 6 Z9 6 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD MAR 1 PY 2000 VL 61 IS 5 AR 055001 DI 10.1103/PhysRevD.61.055001 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600036 ER PT J AU Lamoreaux, SK Golub, R AF Lamoreaux, SK Golub, R TI Remarks on "new experimental limit on the electric dipole moment of the neutron" SO PHYSICAL REVIEW D LA English DT Article AB A new limit for the neutron electric dipole moment has been recently reported. This new limit is obtained by combining the result from a previous experiment with the result from a more recent experiment that has much worse statistical accuracy. We show that the old result has a systematic error possibly four times greater than the new limit, and under the circumstances, averaging of the old and new results is statistically invalid. The conclusion is that it would be more appropriate to quote two independent but mutually supportive limits as obtained from each experiment separately. C1 Univ Calif Los Alamos Natl Lab, Phys Div P23, Los Alamos, NM 87545 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. RP Lamoreaux, SK (reprint author), Univ Calif Los Alamos Natl Lab, Phys Div P23, MS H803, Los Alamos, NM 87545 USA. NR 9 TC 24 Z9 24 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 MAR 1 PY 2000 VL 61 IS 5 AR 051301 DI 10.1103/PhysRevD.61.051301 PG 3 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600001 ER PT J AU Pisarski, RD Rischke, DH AF Pisarski, RD Rischke, DH TI Gaps and critical temperature for color superconductivity SO PHYSICAL REVIEW D LA English DT Article ID DENSITY AB Because of a logarithmic enhancement from soft, collinear magnetic gluons, in dense quark matter the gap for a color superconducting condensate with spin zero depends upon the QCD coupling constant g not as exp(-1/g(2)), Like in Bardeen, Cooper, and Schrieffer (BCS) theory, but as exp(-1/g). In weak coupling, the ratio of the transition temperature to the spin-zero gap at zero temperature is the same as in BCS theory. We classify the gaps with spin one, and find that they are of the same order in g as the spin-zero gap. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 31 TC 147 Z9 149 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 MAR 1 PY 2000 VL 61 IS 5 AR 051501 DI 10.1103/PhysRevD.61.051501 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600002 ER PT J AU Rizzo, TG AF Rizzo, TG TI Testing the nature of Kaluza-Klein excitations at future lepton colliders SO PHYSICAL REVIEW D LA English DT Review ID STANDARD MODEL; PHENOMENOLOGICAL ASPECTS; P(P)OVER-BAR COLLISIONS; SUPERSYMMETRY BREAKING; EXTRA DIMENSIONS; GAUGE BOSONS; Z'; TEV; SEARCH; LIMITS AB With one extra dimension, current high precision electroweak data constrain the masses of the first Kaluza-Klein (KK) excitations of the standard model gauge fields to Lie above similar or equal to 4 TeV. States with masses not much larger than this should be observable at the CERN LHC. However, even for first excitation masses close to this lower bound, the second set of excitations will be too heavy to be produced, thus eliminating the possibility of realizing the cleanest signature for KK scenarios. Previous studies of heavy Z' and W' production in this mass range at the CERN LHC have demonstrated that very little information can be obtained about their couplings to the conventional fermions given the limited available statistics and imply that the CERN LHC cannot distinguish an ordinary Z' from the degenerate pair of the first KK excitations of the gamma and Z. In this paper we discuss the capability of lepton colliders with center of mass energies significantly below the excitation mass to resolve this ambiguity. In addition, we examine how direct measurements obtained on and near the top of the first excitation peak at lepton colliders can confirm these results. For more than one extra dimension we demonstrate that it is likely that the first KK excitation is too massive to be produced at the CERN LHC. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Rizzo, TG (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 150 TC 73 Z9 73 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 MAR 1 PY 2000 VL 61 IS 5 AR 055005 DI 10.1103/PhysRevD.61.055005 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600040 ER PT J AU Vakili, M Arroyo, CG Auchincloss, P de Barbaro, L de Barbaro, P Bazarko, AO Bernstein, RH Bodek, A Bolton, T Budd, H Conrad, J Harris, DA Johnson, RA Kim, JH King, BJ Kinnel, T Koizumi, G Koutsoliotas, S Lamm, MJ Lefmann, WC Marsh, W McFarland, KS McNulty, C Mishra, SR Naples, D Nienaber, P Oreglia, MJ Perera, L Quintas, PZ Romosan, A Sakumoto, WK Schumm, BA Sciulli, FJ Seligman, WG Shaevitz, MH Smith, WH Spentzouris, P Steiner, R Stern, EG Yang, UK Yu, J AF Vakili, M Arroyo, CG Auchincloss, P de Barbaro, L de Barbaro, P Bazarko, AO Bernstein, RH Bodek, A Bolton, T Budd, H Conrad, J Harris, DA Johnson, RA Kim, JH King, BJ Kinnel, T Koizumi, G Koutsoliotas, S Lamm, MJ Lefmann, WC Marsh, W McFarland, KS McNulty, C Mishra, SR Naples, D Nienaber, P Oreglia, MJ Perera, L Quintas, PZ Romosan, A Sakumoto, WK Schumm, BA Sciulli, FJ Seligman, WG Shaevitz, MH Smith, WH Spentzouris, P Steiner, R Stern, EG Yang, UK Yu, J TI Nuclear structure functions in the large-x large-Q(2) kinematic region in neutrino deep inelastic scattering SO PHYSICAL REVIEW D LA English DT Article ID PARTON DISTRIBUTIONS; DEPENDENCE AB Data from the CCFR E770 neutrino deep inelastic scattering experiment at Fermilab contain events with a large Bjorken x (x > 0.7) and high momentum transfer [Q(2) > 50 (GeV/c)(2)]. A comparison of the data with a model based on no nuclear effects at large x shows a significant excess of events in the data. The addition of Fermi gas motion of the nucleons in the nucleus to the model does not explain the excess. Adding a higher momentum tail due to the formation of "quasi-deuterons" makes some improvement. An exponentially falling F-2 proportional to e (-s(x - x0)) at large x, predicted by "multi-quark clusters" and "few-nucleon correlations," can describe the data. A value of s = 8.3 +/- 0.7(stat) +/- 0.7(syst) yields the best agreement with the data. C1 Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Chicago, Chicago, IL 60637 USA. Adelphi Univ, Garden City, NY 11530 USA. Columbia Univ, New York, NY 10027 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Kansas State Univ, Manhattan, KS 66506 USA. Northwestern Univ, Evanston, IL 60208 USA. Univ Rochester, Rochester, NY 14627 USA. Univ Wisconsin, Madison, WI 53706 USA. Xavier Univ, Cincinnati, OH 45207 USA. RP Vakili, M (reprint author), Univ Cincinnati, Cincinnati, OH 45221 USA. NR 20 TC 12 Z9 12 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAR 1 PY 2000 VL 61 IS 5 AR 052003 DI 10.1103/PhysRevD.61.052003 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 290PW UT WOS:000085685600006 ER PT J AU Kessler, DA AF Kessler, DA TI Steady-state cracks in viscoelastic lattice models. II SO PHYSICAL REVIEW E LA English DT Article ID DYNAMIC FRACTURE; INSTABILITY; PROPAGATION AB We present the analytic solution of the mode III steady-state crack in a square lattice with piecewise linear springs and Kelvin viscosity. We show how the results simplify in the limit of large width. We relate our results to a model where the continuum limit is taken only along the crack direction. We present results for small velocity, and for large viscosity, and discuss the structure of the critical bifurcation for small velocity. We compute the size of the process zone wherein standard continuum elasticity theory breaks down. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Math, Berkeley, CA 94720 USA. RP Bar Ilan Univ, Dept Phys, Ramat Gan, Israel. RI Kessler, David/B-1391-2008 OI Kessler, David/0000-0002-5279-1655 NR 14 TC 17 Z9 17 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD MAR PY 2000 VL 61 IS 3 BP 2348 EP 2360 DI 10.1103/PhysRevE.61.2348 PG 13 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 295XM UT WOS:000085994000030 ER PT J AU Qian, YH Chen, SY AF Qian, YH Chen, SY TI Dissipative and dispersive behaviors of lattice-based models for hydrodynamics SO PHYSICAL REVIEW E LA English DT Article ID NAVIER-STOKES EQUATION; BOLTZMANN METHOD; GAS AUTOMATA; TRANSPORT AB Both dissipation and dispersion are present in many complex systems; their interactions through nonlinearity can lead to interesting features. We investigate in this paper the dissipation-dispersion interactions that exist in lattice-based kinetic models for hydrodynamics. The classical Chapman-Enskog expansion is used to derive the dispersion coefficients at third order of Knudsen number. Unlike the dissipation coefficient (viscosity) that is always positive, the dispersion coefficient can be either positive or negative. It would be interesting to know if there is any other physics in these models as compared with the traditional dispersionless Navier-Stokes dynamics. Traveling wave solutions in one dimension are studied and two different solutions have been found: (1) monotonic shack solutions and (2) oscillatory shock solutions, according to different conditions. In two- and three-dimensional systems, whether or not these oscillatory behaviors caused by the interactions between nonlinearity, dissipation, and dispersion have anything to do with vortex cascades (direct or inverse) would be an interesting question and we leave it for future studies. C1 Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10027 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Qian, YH (reprint author), Exa Corp, 450 Bedford St, Lexington, MA 02420 USA. RI Chen, Shiyi/A-3234-2010 NR 17 TC 16 Z9 17 U1 0 U2 4 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 MAR PY 2000 VL 61 IS 3 BP 2712 EP 2716 DI 10.1103/PhysRevE.61.2712 PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 295XM UT WOS:000085994000074 ER PT J AU Martin, JE Venturini, E Odinek, J Anderson, RA AF Martin, JE Venturini, E Odinek, J Anderson, RA TI Anisotropic magnetism in field-structured composites SO PHYSICAL REVIEW E LA English DT Article ID SIMULATION AB Magnetic field-structured composites (FSCs) are made by structuring magnetic particle suspensions in uniaxial or biaxial (e.g., rotating) magnetic fields, while polymerizing the suspending resin. A uniaxial held produces chainlike particle structures, and a biaxial held produces sheetlike particle structures. In either case, these anisotropic structures affect the measured magnetic hysteresis loops, with the magnetic remanence and susceptibility increased significantly along the axis of the structuring field, and decreased slightly orthogonal to the structuring field, relative to the unstructured particle composite. The coercivity is essentially unaffected by structuring. We present data for FSCs of magnetically soft particles, and demonstrate that the altered magnetism can be accounted for by considering the large local fields that occur in FSCs. FSCs of magnetically hard particles show unexpectedly large anisotropies in the remanence, and this is due to the local held effects in combination with the large crystalline anisotropy of this material. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Martin, JE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 17 TC 74 Z9 75 U1 1 U2 13 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 MAR PY 2000 VL 61 IS 3 BP 2818 EP 2830 DI 10.1103/PhysRevE.61.2818 PG 13 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 295XM UT WOS:000085994000089 ER PT J AU May, MJ Fournier, KB Pacella, D Kroegler, H Rice, JE Gregory, B Finkenthal, M Moos, HW Mazzitelli, G Goldstein, WH AF May, MJ Fournier, KB Pacella, D Kroegler, H Rice, JE Gregory, B Finkenthal, M Moos, HW Mazzitelli, G Goldstein, WH TI Observations of the ultraviolet and x-ray brightness profiles and cooling rates of Kr and Ar in magnetically confined fusion plasmas SO PHYSICAL REVIEW E LA English DT Article ID ALCATOR C-MOD; HIGH-Z IMPURITIES; TOKAMAK PLASMAS; SPECTROMETER; EXCITATIONS; MOLYBDENUM; TRANSPORT AB The spatial brightness profiles of Ar and Kr ions have been measured during a set of experiments in which these gases were puffed into FTU (Frascati Tokamak Upgrade) and Alcator C-Mod tokamak plasmas. These profiles were measured by spatially scanning photometrically calibrated vuv and x-ray spectrometers covering 3 to 1700 Angstrom on a shot to shot basis. several simulations of these profiles were performed using the multiple ionization state transport (MIST) code to validate the atomic physics rates used to determine the charge state distribution in the plasmas. A comparison of two sets of atomic physics rates was made. The chosen rates were the original rates in MIST and the more accurate ionization/recombination rate coefficients from the HULLAC atomic code and the current compilations by Mazzotta. The simulations with the more accurate rates could correctly predict the brightness profiles. The simulations with the older rates adequately predicted the Ar brightness profiles but did not accurately predict those of Kr. The inclusion of the excitation autoionization rates which were absent from the MIST code had the most profound effect on the simulated charge state distributions. C1 Johns Hopkins Univ, Dept Phys & Astron, Plasma Spect Grp, Baltimore, MD 21218 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. ENEA Fus, EURATOM Assoc, FTU, Frascati, Roma, Italy. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Inst Natl Rech Sci, Varennes, PQ, Canada. Ctr Canadien Fus Magnet, Varennes, PQ J3X 1S1, Canada. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. RP May, MJ (reprint author), Johns Hopkins Univ, Dept Phys & Astron, Plasma Spect Grp, 34th & N Charles St, Baltimore, MD 21218 USA. NR 34 TC 10 Z9 10 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 MAR PY 2000 VL 61 IS 3 BP 3042 EP 3052 DI 10.1103/PhysRevE.61.3042 PG 11 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 295XM UT WOS:000085994000116 ER PT J AU Lazzaro, E Lontano, M Ryutov, DD AF Lazzaro, E Lontano, M Ryutov, DD TI Linear magnetohydrodynamic waves in a finely stratified plasma SO PHYSICAL REVIEW E LA English DT Article ID PROPAGATION AB In a number of astrophysical systems, the magnetic field, instead of varying over a scale comparable with the "natural'' scale of the object (e.g., tens of thousands of kilometers in the case of the solar convective zone), varies over lengths that are orders of magnitude less than this (e.g., over distances down to 100 km in the case of the magnetic filaments detected in the upper part of the solar convective zone and probably present in much deeper layers). Therefore, the study of the propagation of magnetohydrodynamic (MHD) waves in plasmas with fine magnetic nonuniformities is of considerable general importance for astrophysics. We have developed a general formalism that allows one to treat the propagation of large-scale MHD waves in a finely stratified medium. We demonstrate that the presence of a fine structure of the plasma may produce considerable modifications of the modes existing in a uniform plasma, with a number of propagation modes that may even increase. We also show that the slow MHD mode may experience a collisionless damping, which causes the wave energy to be converted into the energy of the peristaltic modes of the plasma "resonant'' layers. C1 CNR Assoc, ENEA, EURATOM, Ist Fis Plasma Piero Caldirola, I-20125 Milan, Italy. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP CNR Assoc, ENEA, EURATOM, Ist Fis Plasma Piero Caldirola, Via R Cozzi 53, I-20125 Milan, Italy. NR 10 TC 3 Z9 3 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD MAR PY 2000 VL 61 IS 3 BP 3069 EP 3077 DI 10.1103/PhysRevE.61.3069 PG 9 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 295XM UT WOS:000085994000120 ER PT J AU Chowdhury, D Kertesz, J Nagel, K Santen, L Schadschneider, A AF Chowdhury, D Kertesz, J Nagel, K Santen, L Schadschneider, A TI Comment on "Critical behavior of a traffic flow model" SO PHYSICAL REVIEW E LA English DT Letter ID CELLULAR-AUTOMATON MODEL; JAMS; DISTRIBUTIONS; TRANSITION; DISTANCE AB We show that the dynamical structure factor investigated by Roters ct al. [Phys. Rev. E 59, 2672 (1999)] does not allow the determination of the precise nature of the transition in the Nagel-Schreckenberg cellular automata model for traffic flow. We provide evidence for the existence of a crossover instead of a critical point. C1 Univ Cologne, Inst Theoret Phys, D-50937 Cologne, Germany. Indian Inst Technol, Dept Phys, Kanpur 208016, Uttar Pradesh, India. Tech Univ Budapest, Dept Theoret Phys, Budapest, Hungary. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chowdhury, D (reprint author), Univ Cologne, Inst Theoret Phys, D-50937 Cologne, Germany. RI Kertesz, Janos/B-3411-2012; Santen, Ludger/K-8110-2015; OI Santen, Ludger/0000-0001-8478-9667; Schadschneider, Andreas/0000-0002-2054-7973 NR 14 TC 24 Z9 24 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAR PY 2000 VL 61 IS 3 BP 3270 EP 3271 DI 10.1103/PhysRevE.61.3270 PG 2 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 295XM UT WOS:000085994000151 ER PT J AU Kagi, H Parise, JB Cho, H Rossman, GR Loveday, JS AF Kagi, H Parise, JB Cho, H Rossman, GR Loveday, JS TI Hydrogen bonding interactions in phase A [Mg7Si2O8(OH)(6)] at ambient and high pressure SO PHYSICS AND CHEMISTRY OF MINERALS LA English DT Article DE hydrogen bonding; neutron diffraction; dense hydrous magnesium silicate (DHMS); crystal structure; high pressure ID NEUTRON POWDER DIFFRACTION; CHEMICAL-SHIFT TENSORS; STATE NMR-SPECTROSCOPY; MULTIPLE PULSE NMR; SYSTEM MGO-SIO2-H2O; MAGNETIC-RESONANCE; CRYSTAL-STRUCTURE; INFRARED-SPECTRA; SOLIDS; SILICATES AB Neutron powder diffraction data of phase A (Mg7Si2O8(OH)(6)) were collected at ambient pressure and 3.2 GPa (calculated from the compressibility of phase A) from the deuterated compound, and the structure was refined using the Rietveld method. The derived crystal structure implies that hydrogen atoms occupy two distinct sites in phase A, both forming hydrogen bonds of different lengths with the same oxygen atom. This picture is supported by IR spectra, which exhibit two absorption bands at 3400 and 3513 cm(-1) corresponding to OH stretching vibrations, and proton NMR spectra, which display two peaks with equal intensities and isotropic chemical shifts of 3.7 and 5 ppm. The D-D distance [D(1)-D(2) distance] at ambient pressure was found to be 2.09 +/- 0.02 Angstrom from the neutron diffraction data and 2.09 +/- 0.05 Angstrom from the NMR spectra. At 3.2 GPa, there is no statistically significant increase in the O-D interatomic distance while the hydrogen bonding interaction D ... O appears to increase for one of the hydrogen sites, D(1), which has the stronger hydrogen bonding interaction compared with the other hydrogen, D(2), at ambient pressure. The O-D bond valences, determined indirectly from the D ... O distances were 0.86 and 0.91 at ambient pressure, and 0.83 and 0.90 at 3.2 GPa, for D(1) and D(2), respectively. C1 Univ Tokyo, Grad Sch Sci, Earthquake Chem Lab, Tokyo 1130033, Japan. SUNY Stony Brook, Dept Geosci, Ctr High Pressure Res, NSF Funded Sci & Technol Ctr, Stony Brook, NY 11794 USA. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. CALTECH, Dept Geol & Planetary Sci, Pasadena, CA 91125 USA. Univ Edinburgh, Dept Phys & Astron, Edinburgh EH9 3JZ, Midlothian, Scotland. RP Kagi, H (reprint author), Univ Tokyo, Grad Sch Sci, Earthquake Chem Lab, Tokyo 1130033, Japan. OI Rossman, George/0000-0002-4571-6884 NR 52 TC 37 Z9 37 U1 0 U2 8 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0342-1791 J9 PHYS CHEM MINER JI Phys. Chem. Miner. PD MAR PY 2000 VL 27 IS 4 BP 225 EP 233 DI 10.1007/s002690050251 PG 9 WC Materials Science, Multidisciplinary; Mineralogy SC Materials Science; Mineralogy GA 303ZV UT WOS:000086458800001 ER PT J AU Watson, WN AF Watson, WN TI State vectors and physical states SO PHYSICS ESSAYS LA English DT Article DE quantum physics; collapse versus concurrence of state vectors; Bell theorem; nonlocal hidden variables; Schrodinger's cat; Wigner's friend; EPR experiment; double-slit interference; Feynman diagrams; quantum optics ID COMPLEMENTARITY AB Causality and the relativity of simultaneity seem at odds with the apparently sudden, acausal state vector changes ("collapses") characteristic of quantum phenomena. The problem of how physical phenomena can be causally determined, have the probabilities predicted by quantum theory, and be consistent with special relativity appears to be solved by the assumption, essentially the same as one first used by Aharonov, Bergmann, and Lebowitz to address a different problem, that the "initial" and "final" state vectors of a phenomenon or observation, along with certain other state vectors, all represent the system's state at all times. Each member of such an aggregate of state vectors is postulated to represent a different aspect of a physical state rather than a state, so that most of the state vectors in effect constitute a set of nonlocal hidden variables. Various implications of this assumption are illustrated through several physical situations, including the Schrodinger's rat and Wigner's friend problem, two- and three-particle versions of the Einstein-Podolsky-Rosen (EPR) experiment, recently devised variations on the double-slit interference experiment, and interacting particle experiments. Among the results is a somewhat surprising resolution of a paradox in a three-spin Greenberger-Horne-Zeilinger experiment (a three-particle EPR experiment), which involves a logical consequence differing from familiar ideas of quantum physics that has no practical experimental consequence, and the prediction of new experimental phenomena related to the Zou-Wang-Mandel superposed idler system. The potential value of the concepts described as heuristics for new predictions and for developing physical intuition by clarifying the interrelation and coherence of physical principles that would otherwise seem contradictory is briefly discussed. C1 US DOE, Off Sci & Tech Informat, Oak Ridge, TN 37831 USA. RP Watson, WN (reprint author), US DOE, Off Sci & Tech Informat, POB 62, Oak Ridge, TN 37831 USA. NR 21 TC 0 Z9 0 U1 0 U2 0 PU PHYSICS ESSAYS PUBL PI HULL PA C/O ALFT INC, 189 DEVEAULT ST, UNIT NO. 7, HULL, PQ J8Z1S7, CANADA SN 0836-1398 J9 PHYS ESSAYS JI Phys. Essays PD MAR PY 2000 VL 13 IS 1 BP 15 EP 45 PG 31 WC Physics, Multidisciplinary SC Physics GA 417BB UT WOS:000167814500002 ER PT J AU Williams, MB Goode, AR Galbis-Reig, V Majewski, S Weisenberger, AG Wojcik, R AF Williams, MB Goode, AR Galbis-Reig, V Majewski, S Weisenberger, AG Wojcik, R TI Performance of a PSPMT based detector for scintimammography SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article ID PALPABLE BREAST-LESIONS; X-RAY MAMMOGRAPHY; TC-99M METHOXYISOBUTYLISONITRILE; GAMMA-CAMERA; CANCER; DIAGNOSIS; TUMOR; FIELD AB In breast scintigraphy, compact detectors with high intrinsic spatial resolution and small inactive peripheries can provide improvements in extrinsic spatial resolution, efficiency and contrast for small lesions relative to larger conventional cameras. We are developing a pixelated small field-of-view gamma camera for scintimammography. Extensive measurements of the imaging properties of a prototype system have been made, including spatial resolution, sensitivity, uniformity of response, geometric linearity and energy resolution. An anthropomorphic torso phantom providing a realistic breast exit gamma spectrum has been used in a qualitative study of lesion detectability. A new type of breast imaging system that combines scintimammography and digital mammography in a single upright unit has also been developed. The system provides automatic co-registration between the scintigram and the digital mammogram, obtained with the breast in a single configuration. Intrinsic spatial resolution was evaluated via calculation of the phase-dependent modulation transfer unction (MTF). Measurements of extrinsic spatial resolution, sensitivity and uniformity of response were made for two types of parallel hole collimator using NEMA (National Electrical Manufacturers Association) protocols. Geometric linearity was quantified using a line input and least squares analysis of the measured line shape. Energy resolution was measured for seven different crystal types, and the effectiveness of optical grease coupling was assessed. Exit gamma spectra were obtained using a cadmium zinc telluride based spectrometer. These were used to identify appropriate radioisotope concentrations for the various regions of an anthropomorphic torso phantom, such that realistic scatter conditions could be obtained during phantom measurements. For prone scintimammography, a special imaging table was constructed that permits simultaneous imaging of both breasts, as well as craniocaudal views. A dedicated breast imaging system was also developed that permits simultaneous acquisition and superposition of planar gamma images and digital x-ray images. The intrinsic MTF is nonstationary, and is dependent on the phase relationship between the signal and the crystal array matrix. Averaged over all phases, the MTF is approximately 0.75, 0.57 and 0.40 at spatial Frequencies of 1.0, 1.5 and 2.0 cycles per cm, respectively The phase averaged line spread function (LSF) has a FWHM value of 2.6 mm, Following uniformity corrections, the RMS deviations in flood images are only slightly greater than is predicted from counting statistics. Across an 80 mm section of the active area, the differential linearity is 0.83 mm and the absolute linearity 2.0 mm, Using an anthropomorphic torso phantom with detachable breasts, scatter radiation similar to that observed exiting the breast of scintimammography patients was observed. It was observed that scattered gamma rays can constitute the majority of the radiation incident on the detector, but that the scatter-to-primary ratio varies significantly across the field of view, being greatest in the caudal portion of the breast, where scatter from the liver is high. Using a lesion-to-breast concentration ratio of 6:1, a 1.0 cm(3) simulated breast lesion was detectable in lateral images obtained with both the developmental camera and with a clinical camera, while a 0.35 cm(3) lesion was detectable in neither. Utilization of the dual x-ray transmission, gamma emission breast imaging system greatly increases the conspicuity of scintimammographic lesions relative to prone imaging, as well as greatly facilitating the localization and identification of structures in the gamma image. The prototype imaging gamma detector exhibits spatial resolution superior to that of conventional cameras, and comparable uniformity of response and geometric linearity. Because of light losses in the crystals, the energy resolution is inferior to that of single crystal NaI(T1) cameras. Concentration ratios for an anthropomorphic phantom providing realistic scatter conditions and lesion imaging tasks have been identified. A dedicated system for dual modality breast imaging has been developed that provides improved scintigraphic breast imaging relative to the established prone scintimammography techniques. C1 Univ Virginia, Dept Radiol, Charlottesville, VA 22908 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA USA. RP Williams, MB (reprint author), Univ Virginia, Dept Radiol, Charlottesville, VA 22908 USA. FU NCI NIH HHS [R01 CA66232, R01 CA69452] NR 22 TC 50 Z9 51 U1 0 U2 8 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 MAR PY 2000 VL 45 IS 3 BP 781 EP 800 DI 10.1088/0031-9155/45/3/315 PG 20 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA 294AD UT WOS:000085887000015 PM 10730971 ER PT J AU Wunsch, S AF Wunsch, S TI Scaling laws for layer formation in stably-stratified turbulent flows SO PHYSICS OF FLUIDS LA English DT Article AB Experiments have demonstrated that the stirring of a stably-stratified fluid sometimes generates a series of layers of nearly constant density separated by steep density gradients. In this paper, mixing length arguments based on the Kolmogorov picture of turbulence are used to suggest scalings for the layer sizes, gradients, and buoyancy fluxes in the limit of strong turbulence. Experimentally observed layer sizes are consistent with the proposed scaling law. (C) 2000 American Institute of Physics. [S1070-6631(00)01003-5]. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Wunsch, S (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. NR 5 TC 4 Z9 4 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD MAR PY 2000 VL 12 IS 3 BP 672 EP 675 DI 10.1063/1.870272 PG 4 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 282VN UT WOS:000085241100021 ER PT J AU Alexander, FJ Garcia, AL Alder, BJ AF Alexander, FJ Garcia, AL Alder, BJ TI Cell size dependence of transport coefficients in stochastic particle algorithms (vol 10, pg 1540, 1998) SO PHYSICS OF FLUIDS LA English DT Correction C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Computat Sci & Engn, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Alexander, FJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 1 TC 40 Z9 41 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD MAR PY 2000 VL 12 IS 3 BP 731 EP 731 DI 10.1063/1.870278 PG 1 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 282VN UT WOS:000085241100028 ER PT J AU Keiter, PA Scime, EE Balkey, MM Boivin, R Kline, JL Gary, SP AF Keiter, PA Scime, EE Balkey, MM Boivin, R Kline, JL Gary, SP TI Beta-dependent upper bound on ion temperature anisotropy in a laboratory plasma SO PHYSICS OF PLASMAS LA English DT Article ID CYCLOTRON INSTABILITY; EARTHS MAGNETOSHEATH; DEPLETION LAYER; MIRROR PLASMAS; FLUCTUATIONS AB Laser induced fluorescence measurements of ion temperatures, parallel and perpendicular to the local magnetic field, in the Large Experiment on Instabilities and Anisotropies space simulation chamber (a steady-state, high beta, argon plasma) display an inverse correlation between the upper bound on the ion temperature anisotropy and the parallel ion beta (beta = 8 pi nkT/B-2). These observations are consistent with in situ spacecraft measurements in the Earth's magnetosheath and with a theoretical/computational model that predicts that such an upper bound is imposed by scattering from enhanced fluctuations due to growth of the ion cyclotron anisotropy instability (the Alfven ion cyclotron instability). (C) 2000 American Institute of Physics. [S1070-664X(00)05102-8]. C1 W Virginia Univ, Morgantown, WV 26506 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Keiter, PA (reprint author), W Virginia Univ, Morgantown, WV 26506 USA. RI Keiter, Paul/J-3037-2013 NR 24 TC 11 Z9 11 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAR PY 2000 VL 7 IS 3 BP 779 EP 783 DI 10.1063/1.873872 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 286QU UT WOS:000085457300001 ER PT J AU Chao, EH Davidson, RC Paul, SF Morrison, KA AF Chao, EH Davidson, RC Paul, SF Morrison, KA TI Effects of background gas pressure on the dynamics of a nonneutral electron plasma confined in a Malmberg-Penning trap SO PHYSICS OF PLASMAS LA English DT Article ID NEUTRAL GAS; ELASTIC COLLISIONS; IONIZATION GAUGES; POSITRON; RELAXATION; TRANSPORT; EXPANSION; PARTICLE; CATHODE; WAVES AB The effects of electron-neutral collisions on plasma expansion properties and the evolution of the m = 1 diocotron mode are investigated in the Electron Diffusion Gauge (EDG) experiment, a Malmberg-Penning trap with plasma length L-p similar or equal to 15 cm, plasma radius R(p)similar or equal to 1.3 cm, and characteristic electron density 5 x 10(6) cm(-3) < n < 3 x 10(7) cm(-3). Essential features of the m = 1 diocotron mode dynamics in the absence of electron-neutral collisions are verified to behave as expected. The mode frequency, the growth rate of the resistive-wall instability, and the frequency shift at nonlinearly large amplitudes are all in good agreement with theoretical predictions. When helium gas is injected into the trap, the evolution of the mode amplitude is found to be very sensitive to the background gas pressure down to pressures of 5 x 10(-10) Torr, the lowest base pressure achieved in the EDG device. The characteristic time scale tau for nonlinear damping of the m = 1 diocotron mode is observed to scale as P-1/2 over two orders-of-magnitude variation in the background gas pressure P. The evolution of the plasma density profile has also been monitored in order to examine the shape of the evolving density profile n(r,t) and to measure the expansion rate. The density profile is observed to expand radially while maintaining a thermal equilibrium profile shape, as predicted theoretically. While the expansion rate is sensitive to background gas pressure at pressures exceeding 10(-8) Torr, at lower pressures the cross-field transport appears to be dominated by other processes, e.g., asymmetry-induced transport. Finally, the expansion rate is observed to scale approximately as B-3/2 for confining fields ranging from 100 to 600 G. (C) 2000 American Institute of Physics. [S1070-664X(00)03403-0]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Chao, EH (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 33 TC 21 Z9 21 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAR PY 2000 VL 7 IS 3 BP 831 EP 838 DI 10.1063/1.873879 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 286QU UT WOS:000085457300008 ER PT J AU Nebel, RA Finn, JM AF Nebel, RA Finn, JM TI Kinetic and fluid calculations for the periodically oscillating plasma sphere SO PHYSICS OF PLASMAS LA English DT Article AB Previous work [D. C. Barnes and R. A. Nebel, Phys. Plasmas 5, 2498 (1998)] has demonstrated the existence of a one-dimensional self-similar oscillating ion solution which remains in local thermodynamic equilibrium at all times during an oscillation in a harmonic oscillator potential. Here it is shown that all spherically symmetric distributions, in which x, y, and z are independent, are of this form. However, in a real device the density profile will be truncated due to the presence of a wall or conductor. Particle simulations of these truncated profiles are presented and compared with the idealized solutions in the proper limits. Results are also interpreted in terms of rigid rotor rotation in phase space as is appropriate for a harmonic oscillator. Next, it is demonstrated that the deviations from Maxwellian velocity distributions that are observed when the plasma contracts will be quickly rethermalized during the expansion phase. Energy throughput resulting from this rethermalization is discussed. (C) 2000 American Institute of Physics. [S1070-664X(00)04802-3]. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Nebel, RA (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS K717, Los Alamos, NM 87545 USA. NR 7 TC 9 Z9 9 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAR PY 2000 VL 7 IS 3 BP 839 EP 843 DI 10.1063/1.873880 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 286QU UT WOS:000085457300009 ER PT J AU Sesnic, S Gunter, S Gude, A Maraschek, M AF Sesnic, S Gunter, S Gude, A Maraschek, M CA ASDEX Upgrade Team TI Interaction of fast particles with neoclassical tearing modes SO PHYSICS OF PLASMAS LA English DT Article AB Fast particle driven m = 1/n = 1 modes in the form of fishbones frequently initiate neoclassical tearing modes (NTMs) on Axisymmetric Divertor Experiment Upgrade [W. Koppendorfer , 14th International Conference on Plasma Physics and Controlled Fusion (International Atomic Energy Agency, Vienna, 1993), Vol. I, p. 127] and other neutral-beam-injection heated tokamaks, but disappear after the NTMs have reached a quasistationary state. A burst of other magnetohydrodynamic phenomena, described in this paper, appear instead, similar in repetition rate and time signature of frequency and amplitude. They are associated with the growth of the m = 2/n = 2 satellite of the m = 3/n = 2 neoclassical tearing mode, and a transient increase (termed FJ = frequency jump event) in the rotation frequency of the coupled mode system. They lead to a thermal crash, originating at q = 3/2, propagating inwards up to the q = 1 surface. With a lower repetition rate (more characteristic of sawteeth) similar events occur, where a large 1/1 component also appears and the fast crash propagates to the plasma center frequency jump with sawtooth character (FJST). The analogies to the fishbone case suggest that this phenomenon is caused by the interaction with fast particles, which transiently impress their precession frequency on the pre-existing magnetic perturbation of the NTM. (C) 2000 American Institute of Physics. [S1070-664X(00)04402-5]. C1 Max Planck Inst Plasmaphys, EURATOM Assoc, D-85748 Garching, Germany. RP Sesnic, S (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 7 TC 9 Z9 10 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAR PY 2000 VL 7 IS 3 BP 935 EP 939 DI 10.1063/1.873891 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 286QU UT WOS:000085457300021 ER PT J AU Dimits, AM Bateman, G Beer, MA Cohen, BI Dorland, W Hammett, GW Kim, C Kinsey, JE Kotschenreuther, M Kritz, AH Lao, LL Mandrekas, J Nevins, WM Parker, SE Redd, AJ Shumaker, DE Sydora, R Weiland, J AF Dimits, AM Bateman, G Beer, MA Cohen, BI Dorland, W Hammett, GW Kim, C Kinsey, JE Kotschenreuther, M Kritz, AH Lao, LL Mandrekas, J Nevins, WM Parker, SE Redd, AJ Shumaker, DE Sydora, R Weiland, J TI Comparisons and physics basis of tokamak transport models and turbulence simulations SO PHYSICS OF PLASMAS LA English DT Article ID EXB VELOCITY-SHEAR; GYROKINETIC SIMULATIONS; PARTICLE SIMULATION; FLUID SIMULATIONS; TEMPERATURE; GYROFLUID; EQUATIONS; PLASMAS; CONFINEMENT; DRIVEN AB The predictions of gyrokinetic and gyrofluid simulations of ion-temperature-gradient (ITG) instability and turbulence in tokamak plasmas as well as some tokamak plasma thermal transport models, which have been widely used for predicting the performance of the proposed International Thermonuclear Experimental Reactor (ITER) tokamak [Plasma Physics and Controlled Nuclear Fusion Research, 1996 (International Atomic Energy Agency, Vienna, 1997), Vol. 1, p. 3], are compared. These comparisons provide information on effects of differences in the physics content of the various models and on the fusion-relevant figures of merit of plasma performance predicted by the models. Many of the comparisons are undertaken for a simplified plasma model and geometry which is an idealization of the plasma conditions and geometry in a Doublet III-D [Plasma Physics and Controlled Nuclear Fusion Research, 1986 (International Atomic Energy Agency, Vienna, 1987), Vol. 1, p. 159] high confinement (H-mode) experiment. Most of the models show good agreements in their predictions and assumptions for the linear growth rates and frequencies. There are some differences associated with different equilibria. However, there are significant differences in the transport levels between the models. The causes of some of the differences are examined in some detail, with particular attention to numerical convergence in the turbulence simulations (with respect to simulation mesh size, system size and, for particle-based simulations, the particle number). The implications for predictions of fusion plasma performance are also discussed. (C) 2000 American Institute of Physics. [S1070-664X(00)03703-4]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Lehigh Univ, Bethlehem, PA 18015 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08540 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Colorado, Boulder, CO 80309 USA. Univ Texas, Inst Fus Studies, Austin, TX 78712 USA. Gen Atom Inc, San Diego, CA 92186 USA. Georgia Inst Technol, Atlanta, GA 30332 USA. Univ Washington, Seattle, WA 98195 USA. Univ Alberta, Edmonton, AB T6G 2J1, Canada. Chalmers Univ Technol, S-41296 Gothenburg, Sweden. RP Dimits, AM (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. RI Hammett, Gregory/D-1365-2011; Dorland, William/B-4403-2009 OI Hammett, Gregory/0000-0003-1495-6647; Dorland, William/0000-0003-2915-724X NR 77 TC 579 Z9 582 U1 11 U2 83 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAR PY 2000 VL 7 IS 3 BP 969 EP 983 DI 10.1063/1.873896 PG 15 WC Physics, Fluids & Plasmas SC Physics GA 286QU UT WOS:000085457300026 ER PT J AU Qin, H Tang, WM Rewoldt, G Lee, WW AF Qin, H Tang, WM Rewoldt, G Lee, WW TI On the gyrokinetic equilibrium SO PHYSICS OF PLASMAS LA English DT Article ID PARTICLE SIMULATION; HAMILTONIAN-FORMULATION; EQUATIONS; TRANSPORT; TOKAMAKS; MODEL AB Recent developments in gyrokinetic-magnetohydrodynamics (MHD) theory and in electromagnetic gyrokinetic particle simulations raise the question of consistency between the gyrokinetic model and the fluid model. Due to the special characteristics of the guiding center coordinates, it is a nontrivial exercise to show this consistency. In this paper it is shown, in a very general setting, that the gyrokinetic theory and the fluid equations do give an equivalent description of plasma equilibrium (partial derivative/partial derivative t = 0). The fluid continuity equation and momentum equation for equilibrium plasmas are recovered entirely from the gyrokinetic theory. However, it was Spitzer who first realized the importance of consistency between guiding-center motion and fluid equations. In particular, he studied the "apparent paradoxical result" regarding the difference between perpendicular particle flow and guiding-center flow, which will be referred to as the Spitzer paradox in this paper. By recovering the fluid equations from the gyrokinetic theory, we automatically resolve the Spitzer paradox, whose essence is how the perpendicular current and flow are microscopically generated from particles' guiding-center motion. The mathematical construction in the gyrokinetic theory which relates observable quantities in the laboratory frame to the distribution function in the guiding-center coordinates is consistent with Spitzer's original physical picture, while today's gyrokinetic-MHD theory covers a much wider range of problems in a much more general and quantitative way. (C) 2000 American Institute of Physics. [S1070-664X(00)05202-2]. 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 28 TC 16 Z9 16 U1 2 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAR PY 2000 VL 7 IS 3 BP 991 EP 1000 DI 10.1063/1.873898 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 286QU UT WOS:000085457300028 ER PT J AU Davidson, RC Qin, H Shvets, G AF Davidson, RC Qin, H Shvets, G TI A Paul trap configuration to simulate intense non-neutral beam propagation over large distances through a periodic focusing quadrupole magnetic field SO PHYSICS OF PLASMAS LA English DT Article ID VLASOV-MAXWELL EQUATIONS; CHARGED-PARTICLE BEAMS; PURE ELECTRON-PLASMA; STABILITY THEOREM AB This paper considers an intense non-neutral charged particle beam propagating in the z-direction through a periodic focusing quadrupole magnetic field with transverse focusing force, -kappa(q)(s)[x (e) over cap(x)-y (e) over cap(y)], on the beam particles. Here, s = beta(b)ct is the axial coordinate, (gamma(b) - 1)m(b)c(2) is the directed axial kinetic energy of the beam particles, q(b) and m(b) are the charge and rest mass, respectively, of a beam particle, and the oscillatory lattice coefficient satisfies kappa(q)(s + S) = kappa(q)(s), where S is the axial periodicity length of the focusing field. The particle motion in the beam frame is assumed to be nonrelativistic, and the Vlasov-Maxwell equations are employed to describe the nonlinear evolution of the distribution function f(b)(x,y,x',y',s) and the (normalized) self-field potential psi(x,y,s) = q(b)phi(x,y,s)/gamma(b)(3)m(b)beta(b)(2)c(2) in the transverse laboratory-frame phase space (x,y,x('),y(')), assuming a thin beam with characteristic radius r(b) much less than S. It is shown that collective processes and the nonlinear transverse beam dynamics can be simulated in a compact Paul trap configuration in which a long non-neutral plasma column (L much greater than r(p)) is confined axially by applied dc voltages (V) over cap = const on end cylinders at z = +/- L, and transverse confinement in the x-y plane is provided by segmented cylindrical electrodes (at radius r(w)) with applied oscillatory voltages +/- V-0(t) over 90 degrees segments. Here, V-0(t + T) = V-0(t), where T = const is the oscillation period, and the oscillatory quadrupole focusing force on a particle with charge q and mass m near the cylinder axis is -m kappa(q)(t)[x (e) over cap(x)-y (e) over cap(y)], where kappa(q)(t)equivalent to 8qV(0)(t)/pi mr(w)(2). (C) 2000 American Institute of Physics. [S1070-664X(00)01103-4]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Davidson, RC (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 35 TC 45 Z9 45 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAR PY 2000 VL 7 IS 3 BP 1020 EP 1025 DI 10.1063/1.873902 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 286QU UT WOS:000085457300032 ER PT J AU Basol, BM Halani, A Leidholm, C Norsworthy, G Kapur, VK Swartzlander, A Matson, R AF Basol, BM Halani, A Leidholm, C Norsworthy, G Kapur, VK Swartzlander, A Matson, R TI Studies on sulfur diffusion into Cu(In,Ga)Se-2 thin films SO PROGRESS IN PHOTOVOLTAICS LA English DT Article ID SOLAR-CELLS; SELENIZATION; PRECURSORS AB A systematic study was carried out to investigate the distribution of sulfur (S) in CuInSe2 (CIS) and Cu(In,Ga)Se-2 (CIGS) absorbers which were exposed to an H2S atmosphere at elevated temperature. Results demonstrated that S diffusion into CIS layers was a strong function of the original stoichiometry of the absorber before sulfurization. Sulfur inclusion into Cu-rich CIS films was much more favorable compared to S diffusion in Cu-poor layers. The sulfur distribution profile was also strongly influenced by the micro-structure of the original CIS and CIGS layers, with sections of the films with smaller grains accommodating more S. Copyright (C) 2000 John Wiley & Sons, Ltd. C1 ISET Inc, Inglewood, CA 90301 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Basol, BM (reprint author), ISET Inc, 8635 Aviat Blvd, Inglewood, CA 90301 USA. NR 12 TC 38 Z9 38 U1 3 U2 34 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 MAR-APR PY 2000 VL 8 IS 2 BP 227 EP 235 DI 10.1002/(SICI)1099-159X(200003/04)8:2<227::AID-PIP308>3.0.CO;2-G PG 9 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 310MP UT WOS:000086832200003 ER PT J AU King, DL Quintana, MA Kratochvil, JA Ellibee, DE Hansen, BR AF King, DL Quintana, MA Kratochvil, JA Ellibee, DE Hansen, BR TI Photovoltaic module performance and durability following long-term field exposure SO PROGRESS IN PHOTOVOLTAICS LA English DT Article ID PV MODULE; ENCAPSULATION; POTTANT AB This paper summarizes test procedures, results, and implications of in-depth investigations of the performance and durability characteristics of commercial photovoltaic modules after long-term field exposure. New diagnostic test procedures for module reliability research are discussed and illustrated. A collaborative effort t with US module manufactures aimed at achieving 30-year module lifetimes is also described. Copyright (C) 2000 John Wiley & Sons, Ltd. C1 Sandia Natl Labs, Photovolta Syst Components Dept, Albuquerque, NM 87185 USA. RP King, DL (reprint author), Sandia Natl Labs, Photovolta Syst Components Dept, POB 5800, Albuquerque, NM 87185 USA. NR 18 TC 111 Z9 113 U1 1 U2 17 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 MAR-APR PY 2000 VL 8 IS 2 BP 241 EP 256 DI 10.1002/(SICI)1099-159X(200003/04)8:2<241::AID-PIP290>3.0.CO;2-D PG 16 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 310MP UT WOS:000086832200005 ER PT J AU Nobuhara, K Halldin, C Hall, H Karlsson, P Farde, L Hiltunen, J McPherson, DW Savonen, A Bergstrom, KA Pauli, S Swahn, CG Larsson, SA Schnell, PO Sedvall, G AF Nobuhara, K Halldin, C Hall, H Karlsson, P Farde, L Hiltunen, J McPherson, DW Savonen, A Bergstrom, KA Pauli, S Swahn, CG Larsson, SA Schnell, PO Sedvall, G TI Z-IQNP: a potential radioligand for SPECT imaging of muscarinic acetylcholine receptors in Alzheimer's disease SO PSYCHOPHARMACOLOGY LA English DT Article DE Z-IQNP; SPECT; autoradiography; Alzheimer's disease; muscarinic acetylcholine receptor ID IODINE-125-LABELED 1-AZABICYCLO<2.2.2>OCT-3-YL ALPHA-HYDROXY-ALPHA-(1-IODO-1-PRO; POSITRON EMISSION TOMOGRAPHY; POSTMORTEM HUMAN-BRAIN; GUINEA-PIG BRAIN; RAT-BRAIN; BINDING-SITES; CHOLINERGIC RECEPTORS; COMPUTED-TOMOGRAPHY; CEREBRAL-CORTEX; SIGMA-RECEPTOR AB Rationale: The density of the M2 subtype of muscarinic acetylcholine receptors (mAChR) has been shown to be reduced in the brain of patients with Alzheimer's disease (AD). It is therefore of interest to develop a brain imaging method for diagnostic purposes. Z-(R,R)-1-azabicyclo[2.2.2] oct-3-yl alpha-hydroxy-alpha-(1-iodol-propen-3-yl)-alpha-phenylacetate (Z-IQNP) is a muscarinic antagonist with high affinity for the M2 subtype. Objective. The pharmacological characteristics and topographic distribution of radiolabelled Z-IQNP as a radioligand for the M2 mAChR subtype were examined in vitro and in vivo. Methods: Z-IQNP was labelled with I-125 and I-123. Autoradiography was performed on whole-hemisphere cryosections from human post mortem brains. SPECT was performed in a cynomolgus monkey. Results: Autoradiography showed binding of [I-125]Z-IQNP in all brain regions, which was inhibited by the non-selective muscarinic antagonist scopolamine. The addition of BIBN 99, a compound with high affinity for the M2 subtype, inhibited [I-125]Z-IQNP binding particularly in the cerebellum, which has a high density of the M2 subtype. SPECT demonstrated high uptake of [I-123]Z-IQNP in all brain regions. The binding was markedly reduced in all brain regions after pretreatment with the non-selective muscarinic antagonist dexetimide and also the M1 antagonist biperiden. Dexetimide markedly inhibited [I-123]Z-IQNP binding in the cerebellum, which is consistent with a high density of M2-receptors in this region. The sigma receptor binding compound DuP 734 had no effect on Z-IQNP binding either in vitro or in vivo. Conclusions: This study indicates that radiolabelled Z-IQNP has high specificity for mAChR with higher affinity for the M-2 than the M-1 subtype and negligible affinity for sigma recognition sites both in vitro and in vivo. [I-123]Z-IQNP should be useful for future SPECT studies in AD for examination of the density of M2 receptors particularly in the cerebellum. C1 Karolinska Inst, Karolinska Hosp, Dept Clin Neurosci, Psychiat Sect, S-17176 Stockholm, Sweden. Karolinska Inst, Karolinska Hosp, Dept Radiat Phys, S-17176 Stockholm, Sweden. MAP Med Technol Oy, Tikkakoski 41160, Finland. Oak Ridge Natl Lab, Nucl Med Grp, Div Life Sci, Oak Ridge, TN 37831 USA. Kuopio Univ Hosp, Dept Clin Physiol, SF-70210 Kuopio, Finland. RP Nobuhara, K (reprint author), Karolinska Inst, Karolinska Hosp, Dept Clin Neurosci, Psychiat Sect, S-17176 Stockholm, Sweden. NR 55 TC 8 Z9 8 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0033-3158 J9 PSYCHOPHARMACOLOGY JI Psychopharmacology PD MAR PY 2000 VL 149 IS 1 BP 45 EP 55 DI 10.1007/s002139900356 PG 11 WC Neurosciences; Pharmacology & Pharmacy; Psychiatry SC Neurosciences & Neurology; Pharmacology & Pharmacy; Psychiatry GA 304AN UT WOS:000086460500008 PM 10789882 ER PT J AU Wizinowich, P Acton, DS Shelton, C Stomski, P Gathright, J Ho, K Lupton, W Tsubota, K Lai, O Max, C Brase, J An, J Avicola, K Olivier, S Gavel, D Macintosh, B Ghez, A Larkin, J AF Wizinowich, P Acton, DS Shelton, C Stomski, P Gathright, J Ho, K Lupton, W Tsubota, K Lai, O Max, C Brase, J An, J Avicola, K Olivier, S Gavel, D Macintosh, B Ghez, A Larkin, J TI First light adaptive optics images from the Keck II Telescope: A new era of high angular resolution imagery SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article AB Adaptive optics (AO) is a technology that corrects in real time for the blurring effects of atmospheric turbulence, in principle allowing Earth-bound telescopes to achieve their diffraction limit and to "see" as clearly as if they were in space. The power of AO using natural guide stars has been amply demonstrated in recent years on telescopes up to 3-4 m in diameter. The next breakthrough in astronomical resolution was expected to occur with the implementation of AO on the new generation of large, 8-10 m diameter telescopes. In this paper we report the initial results from the first of these AO systems, now coming on line on the 10 m diameter Keck II Telescope. The results include the highest angular resolution images ever obtained from a single telescope (0." 022 and 0." 040 at 0.85 and 1.65 mu m wavelengths, respectively), as well as tests of system performance on three astronomical targets. C1 WM Keck Observ, Kamuela, HI 96743 USA. Canada France Hawaii Telescope Corp, Kamuela, HI 96743 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. RP Wizinowich, P (reprint author), WM Keck Observ, 65-1120 Mamalahoa Highway, Kamuela, HI 96743 USA. EM peterw@keck.hawaii.edu; sacton@keck.hawaiil.edu; cshelton@keck.hawaii.edu; pstomski@keck.hawaii.edu; johng@keck.hawaii.edu; kho@keck.hawaii.edu; wlupton@keck.hawaii.edu; ktsubota@keck.hawaii.edu; lai@cfht.hawaii.edu; max1@llnl.gov; brase1@llnl.gov; an1@llnl.gov; avicola1@llnl.gov; olivier1@llnl.gov; gavel1@llnl.gov; macintosh1@llnl.gov; ghez@astro.ucla.edu; larkin@astro.ucla.edu OI Max, Claire/0000-0003-0682-5436 NR 8 TC 202 Z9 202 U1 3 U2 6 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD MAR PY 2000 VL 112 IS 769 BP 315 EP 319 DI 10.1086/316543 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 292HQ UT WOS:000085788900003 ER PT J AU Macfarlane, PA Clark, JF Davisson, ML Hudson, GB Whittemore, DO AF Macfarlane, PA Clark, JF Davisson, ML Hudson, GB Whittemore, DO TI Late-quaternary recharge determined from chloride in shallow groundwater in the central Great Plains SO QUATERNARY RESEARCH LA English DT Article DE isotope hydrology; paleoclimate; regional flow system; Dakota aquifer; central Great Plains ID SOUTH-CENTRAL KANSAS; STRATIGRAPHIC EVIDENCE; CLIMATE AB An extensive suite of isotopic and geochemical tracers in groundwater has been used to provide hydrologic assessments of the hierarchy of flow systems in aquifers underlying the central Great Plains (southeastern Colorado and western Kansas) of the United States and to determine the late Pleistocene and Holocene paleotemperature and paleorecharge record. Hydrogeologic and geochemical tracer data permit classification of the samples into late Holocene, late Pleistocene-early Holocene, and much older Pleistocene groups. Paleorecharge rates calculated from the Cl concentration in the samples show that recharge rates were at least twice the late Holocene rate during late Pleistocene-early Holocene time, which is consistent with their relative depletion in O-16 and D, Noble gas (Ne, Ar, Kr, Xe) temperature calculations confirm that these older samples represent a recharge environment approximately 5 degrees C cooler than late Holocene values, These results are consistent with the global climate models that show a trend toward a warmer, more arid climate during the Holocene, (C) 2000 University of Washington. C1 Kansas Geol Survey, Geohydrol Sect, Lawrence, KS 66047 USA. Univ Calif Santa Barbara, Dept Geol Sci, Santa Barbara, CA 93106 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Macfarlane, PA (reprint author), Kansas Geol Survey, Geohydrol Sect, Lawrence, KS 66047 USA. RI Whittemore, Donald/M-8875-2015 OI Whittemore, Donald/0000-0003-1679-6675 NR 31 TC 5 Z9 6 U1 2 U2 7 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0033-5894 J9 QUATERNARY RES JI Quat. Res. PD MAR PY 2000 VL 53 IS 2 BP 167 EP 174 DI 10.1006/qres.1999.2113 PG 8 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 295GK UT WOS:000085958200004 ER PT J AU Cooke, DW Bennett, BL Muenchausen, RE Orler, EB Wrobleski, DA AF Cooke, DW Bennett, BL Muenchausen, RE Orler, EB Wrobleski, DA TI X-ray-induced thermally stimulated luminescence and electronic processes in a segmented poly(ester urethane) SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article DE luminescence; poly(ester urethane); optical absorption; free radicals ID POLYURETHANE BLOCK COPOLYMERS; MULTIPLE ENDOTHERMIC BEHAVIOR; FREE-RADICAL YIELDS; PHOTOCHEMICAL BEHAVIOR; INFRARED-ANALYSIS; PYRIMIDINE-BASES; ORGANIC POLYMERS; CONDUCTIVITY; POLYETHYLENE; RESONANCE AB Thermally stimulated luminescence (TSL) glow curves of x-irradiated Estane(R) 5703 exhibit considerable variability as the sample thickness is reduced from 1.25 mm to 20 mu m. The dependence is presumably associated with the diffusion of oxygen into the sample, which alters electronic trapping sites. Specimens of 1.25-mm thickness exhibit reproducible glow curves, are relatively impervious to oxygen exposure, and are characterized by glow peaks at 145, 405 and 440 K. Radiation-induced optical absorption bands occur at 320, 360, 566 and 375 nm, the latter identified with the diphenylmethyl radical. Temperature dependence of these bands, coupled with electron-spin-resonance data, show that TSL is not associated with destruction of the diphenylmethyl radical, but likely results from the onset of polymer molecular motion (gamma relaxation), which releases trapped charges that recombine with other radicals. Radiative emission characteristic of phenyl deexcitation, but in the absence of diphenylmethyl radical destruction, implies that recombination occurs at presently unidentified radical sites, and part of the electronic energy is transferred along the polymer chain to the phenyl group. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Cooke, DW (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MST-8,MS E546, Los Alamos, NM 87545 USA. NR 33 TC 2 Z9 4 U1 1 U2 4 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 MAR PY 2000 VL 58 IS 1 BP 29 EP 38 DI 10.1016/S0969-806X(99)00358-8 PG 10 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA 308DF UT WOS:000086694700005 ER PT J AU Toohey, RE Stabin, MG Watson, EE AF Toohey, RE Stabin, MG Watson, EE TI The AAPM/RSNA physics tutorial for residents - Internal radiation dosimetry: Principles and applications SO RADIOGRAPHICS LA English DT Article; Proceedings Paper CT Annual Meeting and Scientific Assembly of the Radiological-Society-of-North-America (RSNA) CY NOV 29-DEC 06, 1998 CL CHICAGO, ILLINOIS SP Radiol Soc N Amer DE dosimetry; radiations, measurement; radionuclides, radiation dose ID RADIOPHARMACEUTICALS AB Internal dose calculations in nuclear medicine normally use the techniques, equations, and resources provided by the Medical Internal Radiation Dose (MIRD) Committee of the Society of Nuclear Medicine. The MIRD schema uses a unique set of symbols and quantities to calculate the absorbed dose of radiation in any target organ per radioactive decay in any source organ. The calculations involve the energy emitted per radioactive decay, the fraction of the emitted energy that is absorbed in various target organs, the masses of these organs, and both the physical decay and biologic clearance of the injected radioactive material. Standardized mathematical models (phantoms) of the human body and standardized biokinetic models are also used. A computer program, MIRDose, calculates dose tables per unit administered activity of various radiopharmaceuticals. Special care must be taken when nuclear medicine procedures involve pregnant or lactating patients. New methodologies are becoming available to calculate doses to individual patients. C1 Oak Ridge Inst Sci & Educ, Radiat Internal Dose Informat Ctr, Oak Ridge, TN 37831 USA. RP Toohey, RE (reprint author), Oak Ridge Inst Sci & Educ, Radiat Internal Dose Informat Ctr, 140 E Vance Rd, Oak Ridge, TN 37831 USA. NR 17 TC 26 Z9 27 U1 0 U2 3 PU RADIOLOGICAL SOC NORTH AMER PI EASTON PA 20TH AND NORTHAMPTON STS, EASTON, PA 18042 USA SN 0271-5333 J9 RADIOGRAPHICS JI Radiographics PD MAR-APR PY 2000 VL 20 IS 2 BP 533 EP 546 PG 14 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 293FD UT WOS:000085840100018 PM 10715348 ER PT J AU Pisano, ED Johnston, RE Chapman, D Geradts, J Iacocca, MV Livasy, CA Washburn, DB Sayers, DE Zhong, Z Kiss, MZ Thomlinson, WC AF Pisano, ED Johnston, RE Chapman, D Geradts, J Iacocca, MV Livasy, CA Washburn, DB Sayers, DE Zhong, Z Kiss, MZ Thomlinson, WC TI Human breast cancer specimens: Diffraction-enhance imaging with histologic correlation - Improved conspicuity of lesion detail compared with digital radiography SO RADIOLOGY LA English DT Article DE breast radiography, technology; synchrotron ID PHASE-CONTRAST; MAMMOGRAPHY; OBJECT AB Seven breast cancer specimens were examined with diffraction-enhanced imaging at 18 keV with a silicon crystal with use of the silicon 333 reflection in Bragg mode. Images were compared with digital radiographs of the specimen, and regions of increased detail were identified. Six of the seven cases (86%) showed enhanced visibility of surface spiculation that correlated with histopathologic information, including extension of tumor into surrounding tissue. C1 Univ N Carolina, Sch Med, Dept Radiol, Chapel Hill, NC 27599 USA. Univ N Carolina, Sch Med, Dept Pathol, Chapel Hill, NC 27599 USA. Univ N Carolina, Sch Med, Lineberger Comprehens Canc Ctr, Chapel Hill, NC 27599 USA. IIT, Dept Phys, Chicago, IL 60616 USA. IIT, Ctr Synchrotron Radiat Res & Instrumentat, Chicago, IL 60616 USA. Univ Oxford, Nuffield Dept Pathol & Bacteriol, Oxford OX1 2JD, England. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. European Synchrotron Radiat Facil, F-38043 Grenoble, France. RP Pisano, ED (reprint author), Univ N Carolina, Sch Med, Dept Radiol, Manning Dr, Chapel Hill, NC 27599 USA. RI Chapman, Dean/I-6168-2013 OI Chapman, Dean/0000-0001-6590-4156 NR 14 TC 152 Z9 168 U1 0 U2 7 PU RADIOLOGICAL SOC NORTH AMER PI EASTON PA 20TH AND NORTHAMPTON STS, EASTON, PA 18042 USA SN 0033-8419 J9 RADIOLOGY JI Radiology PD MAR PY 2000 VL 214 IS 3 BP 895 EP 901 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 286ZM UT WOS:000085478800045 PM 10715065 ER PT J AU Carlsen, TM Menke, JW Pavlik, BM AF Carlsen, TM Menke, JW Pavlik, BM TI Reducing competitive suppression of a rare annual forb by restoring native California perennial grasslands SO RESTORATION ECOLOGY LA English DT Article DE Amsinckia grandiflora; Poa secunda; rare plants; native plants; exotic plants; interspecific plant competition; light competition; water competition; grassland restoration ID PLANT; POPULATION; WATER AB Populations of the rare annual forb Amsinckia grandiflora may be declining because of competitive suppression by exotic annual grasses, and may perform better in a matrix of native perennial bunchgrasses. We conducted a field competition experiment in which Amsinckia seedlings were transplanted into forty 0.64-m(2) experimental plots of exotic annual grassland or restored perennial grassland. The perennial grassland plots were restored using mature 3 cm-diameter plants of the native perennial bunchgrass Poa secunda planted in three densities. The exotic annual grassland plots were established in four densities through manual removal of existing plants. Both grass types reduced soil water potential with increasing biomass, but this reduction was not significantly different between grass types. Both grass types significantly reduced the production of Amsinckia inflorescences. At low and intermediate densities (dry biomass per unit area of 20-80 g/m(2)), the exotic annual grasses reduced Amsinckia inflorescence number to a greater extent than did Poa, although at high densities (>90 g/m(2)) both grass types reduced the number of Amsinckia inflorescences to the same extent. The response of Amsinckia inflorescence number to Poa biomass was linear, whereas the same response to the annual grass biomass is logarithmic, and appeared to be related to graminoid cover. This may be because of the different growth forms exhibited by the two grass types. Results of this research suggest that restored native perennial grasslands at intermediate densities have a high habitat value for the potential establishment of the native annual A. grandiflora. C1 Univ Calif Lawrence Livermore Natl Lab, Environm Restorat Div, Livermore, CA 94551 USA. Univ Calif Davis, Dept Agron & Range Sci, Davis, CA 95616 USA. Mills Coll, Dept Biol, Oakland, CA 94613 USA. RP Carlsen, TM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Environm Restorat Div, Livermore, CA 94551 USA. OI Menke, John/0000-0002-0924-4349 NR 39 TC 30 Z9 32 U1 4 U2 11 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 1061-2971 J9 RESTOR ECOL JI Restor. Ecol. PD MAR PY 2000 VL 8 IS 1 BP 18 EP 29 DI 10.1046/j.1526-100x.2000.80004.x PG 12 WC Ecology SC Environmental Sciences & Ecology GA 296FM UT WOS:000086013300004 ER PT J AU Qiu, ZQ Bader, SD AF Qiu, ZQ Bader, SD TI Surface magneto-optic Kerr effect SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Review ID SINGLE LAYER EQUIVALENCE; STRIPE DOMAIN-STRUCTURES; THIN FERROMAGNETIC FILM; ULTRATHIN CO FILMS; FE FILMS; MAGNETIZATION REVERSAL; MULTILAYERED FILMS; OBLIQUE-INCIDENCE; COBALT FILMS; ANISOTROPY AB The surface magneto-optic Kerr effect (SMOKE) has significantly impacted research on magnetic thin films. This is due to its sensitivity, local probing nature, and experimental simplicity. The polar and longitudinal Kerr effects are characterized by a complex rotation of the plane of polarization of linearly polarized incident light upon reflection from the surface of a ferromagnetic material. The rotation is directly related to the magnetization of the material within the probing region of the light. Light penetrates into metals > 20 nm deep, but the SMOKE technique derives its surface sensitivity from the limited thickness of the deposited magnetic film, which can be as thin as one atomic layer. Basic principles, experimental arrangements, and applications of SMOKE are reviewed in order to acquaint the nonspecialist with the technique and place it into perspective. (C) 2000 American Institute of Physics. [S0034-6748(00)00103-9]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Bader, SD (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Bader, Samuel/A-2995-2013; Qiu, Zi Qiang/O-4421-2016 OI Qiu, Zi Qiang/0000-0003-0680-0714 NR 111 TC 205 Z9 207 U1 16 U2 144 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAR PY 2000 VL 71 IS 3 BP 1243 EP 1255 DI 10.1063/1.1150496 PG 13 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 290QZ UT WOS:000085688600001 ER PT J AU Yaney, PP Kliner, DAV Schrader, PE Farrow, RL AF Yaney, PP Kliner, DAV Schrader, PE Farrow, RL TI Distributed-feedback dye laser for picosecond ultraviolet and visible spectroscopy SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID ULTRASHORT PULSE GENERATION; ATMOSPHERIC-PRESSURE FLAMES; POLARIZATION SPECTROSCOPY; OH; LIFETIMES; FS AB We describe the design and operation of a tunable, picosecond laser system for use in time-resolved spectroscopic measurements in the visible and ultraviolet (UV) spectral region. The laser is designed for fine tuning and high wavelength stability. A Nd:YAG-pumped distributed-feedback dye laser (DFDL) generates pulses that are similar to 100 ps in duration with a nearly transform-limited linewidth (similar to 5 GHz) at a 20 Hz repetition rate. The DFDL pulses are amplified in two bow-tie amplifiers, providing pulse energies of up to 3.0 mJ; the amplified pulses may be frequency doubled to the UV spectral region, providing up to 1.0 mJ. The DFDL wavelength is computer stabilized to within +/- 0.8 pm (+/- 0.7 GHz, two standard deviations), allowing the wavelength to be stationed on a narrow atomic or molecular transition or permitting nearly continuous spectral scans. Application of the laser system to studies of OH energy transfer has been demonstrated; both laser-induced-fluorescence and degenerate-four-wave-mixing spectra have been recorded. (C) 2000 American Institute of Physics. [S0034-6748(00)05003-6]. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. Univ Dayton, Dept Phys, Dayton, OH 45469 USA. RP Farrow, RL (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. NR 34 TC 26 Z9 26 U1 1 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAR PY 2000 VL 71 IS 3 BP 1296 EP 1305 DI 10.1063/1.1150455 PG 10 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 290QZ UT WOS:000085688600008 ER PT J AU Jarvis, GK Shiell, RC Hepburn, JW Song, Y Ng, CY AF Jarvis, GK Shiell, RC Hepburn, JW Song, Y Ng, CY TI Pulsed field ionization-photoion spectroscopy using two-bunch synchrotron radiation: Time-of-flight selection scheme SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID HIGH-RESOLUTION; PHOTOELECTRON BANDS; THRESHOLD; STATES; IONS AB We have demonstrated that the time-of-flight (TOF) selection method for pulsed field ionization (PFI) photoelectron detection [Jarvis , Rev. Sci. Instrum. 70, 2615 (1999)] can also be applied for the detection of PFI-photoions (PFI-PIs) using the two-bunch synchrotron radiation at the Advanced Light Source. By employing the supersonic beam technique to lower the translational temperature of the sample gas, we show that background prompt ions formed in direct and spontaneous autoionization processes arrive at the ion detector in a pattern similar to that of the vacuum ultraviolet light bunches. The PFI-PIs formed at dark gaps can be designed to arrive at the detector in between adjacent prompt ion peaks, enabling the gating of the PFI-PI signal with only minor contamination from background prompt ions. This experiment has revealed important considerations for the design of a general TOF selection scheme for PFI-PI detection using synchrotron radiation. (C) 2000 American Institute of Physics. [S0034-6748(00)03003-3]. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP US DOE, Ames Lab, Ames, IA 50011 USA. EM cyng@ameslab.gov NR 24 TC 9 Z9 9 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0034-6748 EI 1089-7623 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAR PY 2000 VL 71 IS 3 BP 1325 EP 1331 DI 10.1063/1.1150458 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 290QZ UT WOS:000085688600011 ER PT J AU Kwan, TJT Snell, CM AF Kwan, TJT Snell, CM TI Plasma and ion barrier for electron beam spot stability SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB High-current electron beams of small spot size are used for high-resolution x-ray radiography of dense objects. Intense energy deposition in the bremsstrahlung target causes generation of ions which can propagate upstream and disrupt the electron beam. We have investigated the use of a thin beryllium foil placed 1-2 cm in front of the target, which serves as a barrier for the ions but is essentially transparent to the incoming electron beam. Analysis and computer simulations confirm that this confinement method will halt ion propagation and preserve the spot size stability of the electron beam. (C) 2000 American Institute of Physics. [S0034-6748(00)04203-9]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kwan, TJT (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 8 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAR PY 2000 VL 71 IS 3 BP 1363 EP 1366 DI 10.1063/1.1150464 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 290QZ UT WOS:000085688600017 ER PT J AU Goncharov, A Protsenko, I Yushkov, G Brown, IG AF Goncharov, A Protsenko, I Yushkov, G Brown, IG TI Development of a high-current plasma lens for focusing broad beams of heavy metal ions SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 8th International Conference on Ion Sources CY SEP 06-10, 1999 CL KYOTO, JAPAN AB We describe the results of investigations of the manipulation of moderate energy, large area beams of heavy metal ions by a high-current electrostatic plasma lens. Electrostatic plasma lenses are essential for the focusing of high-current heavy ion beams with moderate energies of 10-100 keV. In our experiments, beams of carbon, copper, zinc, and tantalum (separately) were formed by a repetitively pulsed vacuum arc ion source with energy in the range 10-50 keV, beam current up to 0.5 A, and initial diameter 10 cm. The characteristics of the focusing of the ion beam passing through the lens were measured by a radially movable, magnetically suppressed Faraday cup. The plasma lens focusing properties were determined for a number of different distributions of the lens ring-electrode potentials. We have shown that by changing the lens electrode potential distribution we can control the lens focusing, in both the convergent and divergent regimes. Some features of heavy metal ion beam focusing under these conditions are discussed. The experiments demonstrate the versatile possibilities of the plasma lens for use with moderate-energy, high-current, heavy ion beams. (C) 2000 American Institute of Physics. [S0034-6748(00)50202-0]. C1 Natl Acad Sci Ukraine, Inst Phys, UA-252650 Kiev, Ukraine. Russian Acad Sci, Inst High Current Elect, Tomsk 634055, Russia. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Goncharov, A (reprint author), Natl Acad Sci Ukraine, Inst Phys, UA-252650 Kiev, Ukraine. RI Yushkov, Georgy/O-8024-2015 OI Yushkov, Georgy/0000-0002-7615-6058 NR 6 TC 3 Z9 3 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAR PY 2000 VL 71 IS 3 BP 1401 EP 1404 DI 10.1063/1.1150469 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 290QZ UT WOS:000085688600023 ER PT J AU Beauvais, PY Ferdinand, R Gobin, R Lagniel, JM Leroy, PA Celona, L Ciavola, G Gammino, S Pottin, B Sherman, J AF Beauvais, PY Ferdinand, R Gobin, R Lagniel, JM Leroy, PA Celona, L Ciavola, G Gammino, S Pottin, B Sherman, J TI Emittance improvement of the electron cyclotron resonance high intensity light ion source proton beam by gas injection in the low energy beam transport SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 8th International Conference on Ion Sources CY SEP 06-10, 1999 CL KYOTO, JAPAN AB SILHI is the ECR high intensity light ion source studied in France at C.E.A. Saclay. This is the source for the injector of the high intensity proton injector prototype developed by a CNRS-IN2P3 collaboration. 80 mA at 95 keV beams with a rms normalized r-r' emittance lower than 0.3 pi mm mrad and a proton fraction better than 85% are currently produced. Recently, it has been found that the injection in the low energy beam transport of a buffer gas had a strong effect on the emittance measured 1 m downstream of the focusing solenoid. By adding several gases (H-2, N-2, Ar, Kr), improvements as great as a factor of 3 have been observed. The emittance has been measured by means of an r-r' emittance measurement unit equipped with a sampling hole and a wire profile monitor, both moving across the beam. Simultaneously, the space charge compensation factor is measured using a four-grid analyzer unit. In this article all results of these experiments are presented and discussed. A first explanation of the emittance reduction phenomenon and possible consequences on the injector operation is given. (C) 2000 American Institute of Physics. [S0034-6748(00)65402-3]. C1 CEA Saclay, F-91191 Gif Sur Yvette, France. Ist Nazl Fis Nucl, I-95123 Catania, Italy. IN2P3, CNRS, F-91495 Orsay, France. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Beauvais, PY (reprint author), CEA Saclay, F-91191 Gif Sur Yvette, France. OI Celona, Luigi/0000-0002-6328-5926 NR 5 TC 15 Z9 15 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAR PY 2000 VL 71 IS 3 BP 1413 EP 1416 DI 10.1063/1.1150448 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 290QZ UT WOS:000085688600026 ER PT J AU Haworth, MD Englert, TJ Hendricks, KJ Lemke, RW Luginsland, JW Shiffler, DS Spencer, TA AF Haworth, MD Englert, TJ Hendricks, KJ Lemke, RW Luginsland, JW Shiffler, DS Spencer, TA TI Comprehensive diagnostic suite for a magnetically insulated transmission line oscillator SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID ELECTRON-BEAM; MILO; FREQUENCY AB The magnetically insulated transmission line oscillator (MILO) is a gigawatt-class cross-field microwave tube that requires no external magnetic field due to inherent self-magnetic insulation. The tube operates with a 500 kV, 60 kA electron beam which, along with high rf fields, poses quite a challenge for diagnosing the device. We report on the comprehensive set of experimental diagnostics (both beam and microwave) employed in the MILO experiment, and show how these diagnostics, teamed with particle-in-cell computer simulations, have been instrumental in discovering problems with the tube. [S0034-6748(00)01903-1]. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. Numerex, Albuquerque, NM 87106 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Haworth, MD (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 37 TC 25 Z9 28 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAR PY 2000 VL 71 IS 3 BP 1539 EP 1547 DI 10.1063/1.1150500 PG 9 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 290QZ UT WOS:000085688600049 ER PT J AU Hoffmann, MM Addleman, RS Fulton, JL AF Hoffmann, MM Addleman, RS Fulton, JL TI Short-pathlength, high-pressure flow cell for static and time-resolved infrared spectroscopy suitable for supercritical fluid solutions including hydrothermal systems SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB An optical flow cell for high pressures and temperatures is described. The use of a novel window design allows for a precise, fixed optical pathlength that can be varied by use of spacers that range from a few micrometers to several millimeters. The cell pathlength is not affected by changes in pressure or temperature. The novel window design may be applicable to other high-pressure spectroscopic cells. The flow-cell design has a minimal sample dead volume, which is important for kinetic studies. The design eliminates the need for brazing or for a soft-sealing material for the optical windows, thereby minimizing the number of materials in contact with the sample. Using only diamond and platinum or platinum alloys as the corrosion resistant materials, the design is optimized for the study of aqueous solutions at high temperatures. Infrared spectra of an aqueous sodium tungstate solution up to 400 degrees C and 380 bar pressure are presented. Time-resolved infrared data are also presented for the ultraviolet photolysis reaction of beta-naphthoyl azide in supercritical carbon dioxide. (C) 2000 American Institute of Physics. [S0034-6748(00)01503-3]. C1 Pacific NW Lab, Environm & Hlth Sci Div, Richland, WA 99352 USA. RP Fulton, JL (reprint author), Pacific NW Lab, Environm & Hlth Sci Div, Richland, WA 99352 USA. NR 16 TC 17 Z9 17 U1 3 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAR PY 2000 VL 71 IS 3 BP 1552 EP 1556 DI 10.1063/1.1150493 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 290QZ UT WOS:000085688600051 ER PT J AU Duan, YX Su, YX Jin, Z Abeln, SP AF Duan, YX Su, YX Jin, Z Abeln, SP TI Design and development of a highly sensitive, field portable plasma source instrument for on-line liquid stream monitoring and real-time sample analysis SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID ATOMIC-EMISSION-SPECTROMETRY; MICROWAVE PLASMA; FLUORESCENCE SPECTROMETRY; ANALYTICAL PERFORMANCE; ATMOSPHERIC-PRESSURE; MASS-SPECTROMETRY; VAPOR-GENERATION; TORCH; ARGON; MERCURY AB The development of a highly sensitive, field portable, low-powered instrument for on-site, real-time liquid waste stream monitoring is described in this article. A series of factors such as system sensitivity and portability, plasma source, sample introduction, desolvation system, power supply, and the instrument configuration, were carefully considered in the design of the portable instrument. A newly designed, miniature, modified microwave plasma source was selected as the emission source for spectroscopy measurement, and an integrated small spectrometer with a charge-coupled device detector was installed for signal processing and detection. An innovative beam collection system with optical fibers was designed and used for emission signal collection. Microwave plasma can be sustained with various gases at relatively low power, and it possesses high detection capabilities for both metal and nonmetal pollutants, making it desirable to use for on-site, real-time, liquid waste stream monitoring. An effective in situ sampling system was coupled with a high efficiency desolvation device for direct-sampling liquid samples into the plasma. A portable computer control system is used for data processing. The new, integrated instrument can be easily used for on-site, real-time monitoring in the field. The system possesses a series of advantages, including high sensitivity for metal and nonmetal elements; in situ sampling; compact structure; low cost; and ease of operation and handling. These advantages will significantly overcome the limitations of previous monitoring techniques and make great contributions to environmental restoration and monitoring. [S0034-6748(00)03103-8]. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Duan, YX (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, CS 9,MS K484, Los Alamos, NM 87545 USA. NR 29 TC 20 Z9 20 U1 2 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAR PY 2000 VL 71 IS 3 BP 1557 EP 1563 DI 10.1063/1.1150501 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 290QZ UT WOS:000085688600052 ER PT J AU Phillips, DH Foss, JE Buckner, ER Evans, RM FitzPatrick, EA AF Phillips, DH Foss, JE Buckner, ER Evans, RM FitzPatrick, EA TI Response of surface horizons in an oak forest to prescribed burning SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID SOIL AB The reduction of forest floor ground cover and litter layers by prescribed fires may alter the morphology (field and micro) and physical properties of surface horizons. This study determined long-term (35 yr) changes in surface horizon bulk density, organic matter concentration and content, and morphology in response to periodic (5 yr) and annual (1 yr) prescribed fires. Soils were fine-silty, siliceous, thermic Glossic Fragiuldults, supporting mixed oak vegetation in middle Tennessee. Upper mineral soils (0- to 2-cm and 0- to 7.6-cm depths) were sampled and detailed field descriptions made. Periodic and control plots had a thin layer of Oi, Oe, and Oa horizons 5 yr after the 1993 burn, whereas on annual burn plots a 1- to 2-cm charred layer was present. Significant reductions in organic matter concentration and mean thickness of the A horizon were found from burning (A horizons thicknesses were 6.4, 4.6, and 2.9 cm in control, periodic, and annual plots, respectively), Periodic burns did not significantly alter the organic matter and bulk density of the upper 7.6 cm of mineral soil; however, annual burns did result in significantly higher bulk densities (1.01, 1.07, and 1.29 Mg m(-3) in control, periodic, and annual plots, respectively) and lower organic matter concentrations and contents. Microscopic investigations confirmed that compaction was increased from annual burning. Thin sections also revealed that the granular structure of the A horizons in control and periodic plots resulted from bioterbation of macro and mesofauna, fungi, and roots. Long-term annual burning greatly affected surface soil properties, whereas periodic burning on a 5-yr cycle had only limited effects. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Plant & Soil Sci, Knoxville, TN 37901 USA. Univ Tennessee, Dept Forestry, Knoxville, TN 37901 USA. Univ Tennessee, Forestry Exp Stn, Knoxville, TN 37901 USA. Dept Plant & Soil Sci, Aberdeen, Scotland. RP Phillips, DH (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008,MS 36, Oak Ridge, TN 37831 USA. EM phillipsdh@ornl.gov RI Phillips, Debra/F-1828-2010 OI Phillips, Debra/0000-0001-8548-7409 NR 29 TC 19 Z9 20 U1 3 U2 11 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD MAR-APR PY 2000 VL 64 IS 2 BP 754 EP 760 PG 7 WC Soil Science SC Agriculture GA 356MC UT WOS:000089446200043 ER PT J AU Pern, FJ Glick, SH AF Pern, FJ Glick, SH TI Photothermal stability of encapsulated Si solar cells and encapsulation materials upon accelerated exposures SO SOLAR ENERGY MATERIALS AND SOLAR CELLS LA English DT Article DE photothermal stability; encapsulation materials; EVA browning/discoloration; solar cell degradation; spectroscopic characterization ID PV MODULES; DEGRADATION; DESERT AB We have conducted a series of accelerated exposure test (AET) studies for various samples of crystalline-Si (c-Si) and amorphous-Si (a-Si) cells that were encapsulated with different superstrates, pottants, and substrates. Transmittance, fluorescence, color indices, impedance spectroscopy, laser optical beam induced current (OBIC), and light and dark current-voltage (I-V) measurements were used to characterize the samples. Nonuniform browning patterns of ethylene vinyl acetate (EVA) pottants were observed for glass/EVA/glass-encapsulated c-Si cell samples under solar simulator exposures at elevated temperatures. The EVA discolored gradually into a yellow-brown color when exposed under similar to 7.5 ultraviolet (UV) suns at a black panel temperature (BPT) of similar to 85 degrees C, and very rapidly into a dark brown color when exposed under similar to 9.0 UV suns at a BPT of similar to 145 degrees C. The latter conditions also caused extensive delamination of a polyolefin-based thermoplastic pottant laminated between two borosilicate plates. No visible color change of EVA could be observed for the c-Si cell samples heated in an oven at 85 degrees C or exposed under similar to 1.2 UV suns at BPT = 60-65 degrees C or 80-85 degrees C. Under similar to 1.2 UV suns exposure at a BPT of 60-65 degrees C, the thin layers of EVA or silicone in the lightweight c-Si cell samples, which were laminated in a polymer/solar cell/polymer configuration with Tedlar or Tefzel films, did not discolor because of photobleaching reactions. In comparison, the polyester or nylon superstrate films turned yellow on laminates of polymer/a-Si/polymer minimodules, and significant delamination was observed for the polyester/EVA layers. For all c-Si cell samples tested, irregular changes in the I-V parameters were observed that could not be attributed only to transmittance changes of the superstrate/pottant layers. Under UV-transmitting polymer superstrate films, current/efficiency losses were greater for the c-Si and a-Si cells that were laminated with silicone-type adhesives than with EVA or polyethylene pottants. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Ctr Photovolta, Natl Renewable Energy Lab, Engn & Reliabil Div, Golden, CO 80401 USA. RP Pern, FJ (reprint author), Natl Ctr Photovolta, Natl Renewable Energy Lab, Engn & Reliabil Div, 1617 Cole Blvd, Golden, CO 80401 USA. NR 28 TC 24 Z9 28 U1 2 U2 27 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0248 J9 SOL ENERG MAT SOL C JI Sol. Energy Mater. Sol. Cells PD MAR 1 PY 2000 VL 61 IS 2 BP 153 EP 188 DI 10.1016/S0927-0248(99)00108-7 PG 36 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 281FR UT WOS:000085147700006 ER PT J AU Smallwood, DO AF Smallwood, DO TI The correct balance between analysis and test SO SOUND AND VIBRATION LA English DT Editorial Material C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Smallwood, DO (reprint author), Sandia Natl Labs, POB 5800,MS 0553, Albuquerque, NM 87185 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU ACOUSTICAL PUBL INC PI BAY VILLAGE PA 27101 E OVIATT RD PO BOX 40416, BAY VILLAGE, OH 44140 USA SN 0038-1810 J9 SOUND VIB JI Sound Vib. PD MAR PY 2000 VL 34 IS 3 BP 6 EP 7 PG 2 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 306CL UT WOS:000086578900002 ER PT J AU Biggs, JR Bennett, KD Torrez-Martinez, N Hjelle, BL AF Biggs, JR Bennett, KD Torrez-Martinez, N Hjelle, BL TI Sin nombre virus antibody prevalence in rodents of north-central New Mexico SO SOUTHWESTERN NATURALIST LA English DT Article ID SOUTHWESTERN UNITED-STATES; HANTAVIRUS PULMONARY SYNDROME; GENETIC IDENTIFICATION; PEROMYSCUS-MANICULATUS; HEMORRHAGIC-FEVER; RENAL SYNDROME; EPIDEMIOLOGY; TRANSMISSION; INFECTIONS; OUTBREAK AB From 1993 to 1998, thr Biology Team at Los Alamos National Laboratory surveyed small mammal populations in north-central New Mexico using live capture-recapture methods to determine hantavirus seroprevalences. Deer mire (Peromyscus maniculatus), western harvest mice (Reithrodontomys megalotis), white-footed mice (II leucopus), and voles (Microtus sp.) tested positive for hantavirus. We observed a decreasing trend in seroprevalence of deer mice from 1993 to 1995-1996 but an increasing trend in seroprevalence rates ill voles. Seroprevalences and deer mouse density were not correlated and varied substantially at sampling locations, therefore microhabitat (i.e., cover, food availability) should be more closely examined as to its relationship with hantavirus in rodent populations. C1 Univ Calif Los Alamos Natl Lab, Ecol Grp, Los Alamos, NM 87545 USA. RP Biggs, JR (reprint author), Univ Calif Los Alamos Natl Lab, Ecol Grp, POB 1663, Los Alamos, NM 87545 USA. NR 22 TC 1 Z9 1 U1 1 U2 1 PU SOUTHWESTERN ASSN NATURALISTS PI SAN MARCOS PA SOUTHWEST TEXAS STATE UNIV, DEPT BIOLOGY, 601 UNIVERSITY DR, SAN MARCOS, TX 78666 USA SN 0038-4909 J9 SOUTHWEST NAT JI Southw. Natural. PD MAR PY 2000 VL 45 IS 1 BP 61 EP 66 DI 10.2307/3672552 PG 6 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 301ZM UT WOS:000086340500008 ER PT J AU Hein, EW Myers, OB AF Hein, EW Myers, OB TI The effect of surveyor experience on frequency of recapture in pierid butterflies SO SOUTHWESTERN NATURALIST LA English DT Article ID PROBABILITY; ABUNDANCE; CAPTURE C1 Los Alamos Natl Lab, Environm Sci Grp, Los Alamos, NM 87545 USA. RP Hein, EW (reprint author), US Fish & Wildlife Serv, 2105 Osuna NE, Albuquerque, NM 87103 USA. RI Myers, Orrin/F-1130-2010 NR 15 TC 4 Z9 4 U1 0 U2 2 PU SOUTHWESTERN ASSOC NATURALISTS PI SAN MARCOS PA SOUTHWEST TEXAS STATE UNIV, DEPT BIOLOGY, 601 UNIVERSITY DR, SAN MARCOS, TX 78666 USA SN 0038-4909 EI 1943-6262 J9 SOUTHWEST NAT JI Southw. Natural. PD MAR PY 2000 VL 45 IS 1 BP 67 EP 69 DI 10.2307/3672553 PG 3 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 301ZM UT WOS:000086340500009 ER PT J AU Roberts, PM Venkitaraman, A Sharma, MM AF Roberts, PM Venkitaraman, A Sharma, MM TI Ultrasonic removal of organic deposits and polymer-induced formation damage SO SPE DRILLING & COMPLETION LA English DT Article AB Experiments were conducted to investigate ultrasonic energy for reducing near-wellbore formation damage caused by organic deposits and polymers. It is shown that mechanical agitation provided by the acoustic waves re-suspends the paraffin and restores the effective permeability of the core to its undamaged condition. The depth of treatment is approximately 12 to 15 cm. This suggests that an acoustic source with or without solvents may provide an effective method of removing paraffins from the wellbore and the near-wellbore region. Ultrasonics was not as effective at restoring permeability damage caused by polymers. Our results demonstrate that ultrasonic cleaning may be a viable method for cleaning the near-wellbore region when paraffin precipitation is a problem. The method would be particularly effective at treating long sections of pay where chemical methods may be too expensive. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Texas, Austin, TX 78712 USA. RP Roberts, PM (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 7 TC 17 Z9 18 U1 0 U2 0 PU SOC PETROLEUM ENG PI RICHARDSON PA 222 PALISADES CREEK DR,, RICHARDSON, TX 75080 USA SN 1064-6671 J9 SPE DRILL COMPLETION JI SPE Drill. Complet. PD MAR PY 2000 VL 15 IS 1 BP 19 EP 24 PG 6 WC Engineering, Petroleum SC Engineering GA 295VT UT WOS:000085989100004 ER PT J AU Zhang, DX Li, LY Tchelepi, HA AF Zhang, DX Li, LY Tchelepi, HA TI Stochastic formulation for uncertainty analysis of two-phase flow in heterogeneous reservoirs SO SPE JOURNAL LA English DT Article; Proceedings Paper CT 1999 SPE Reservoir Simulation Symposium CY FEB 14-17, 1999 CL HOUSTON, TEXAS SP SPE ID SOLUTE FLUX APPROACH; REACTIVE TRANSPORT; GEOLOGICAL MEDIA; GROUNDWATER-FLOW; IMMISCIBLE FLOW; POROUS-MEDIA AB In this article we use a direct approach to quantify the uncertainty in Row performance predictions due to uncertainty in the reservoir description. We solve moment equations derived from a stochastic mathematical statement of immiscible nonlinear two-phase how in heterogeneous reservoirs. Our stochastic approach is different from the Monte Carlo approach. In the Monte Carlo approach, the prediction uncertainty is obtained through a statistical postprocessing of flow simulations, one for each of a large number of equiprobable realizations of the reservoir description. We treat permeability as a random space function. In rum, saturation and flow velocity are random fields. We operate in a Lagrangian framework to deal with the transport problem. That is, we transform to a coordinate system attached to streamlines (time, travel time, and transverse displacements). We retain the normal Eulerian (space and time) framework for the total velocity, which we take to be dominated by the heterogeneity of the reservoir. We derive and solve expressions for the first (mean) and second (variance) moments of the quantities of interest; We demonstrate the applicability of our approach to complex flow geometry. Closed outer boundaries and converging/diverging flows due to the presence of sources/sinks require special mathematical and numerical treatments. General expressions for the moments of total velocity, travel time, transverse displacement, water saturation, production rate, and cumulative recovery are presented and analyzed. A detailed comparison of the moment solution approach with high-resolution Monte Carlo simulations for a variety of two-dimensional problems is presented. We also discuss the advantages and limits of the applicability of the moment equation approach relative to the Monte Carlo approach. C1 Univ Calif Los Alamos Natl Lab, Geoanal Grp EES5, Los Alamos, NM 87544 USA. Chevron Petr Technol Co, San Ramon, CA USA. RP Zhang, DX (reprint author), Univ Calif Los Alamos Natl Lab, Geoanal Grp EES5, Los Alamos, NM 87544 USA. RI Zhang, Dongxiao/D-5289-2009; Tchelepi, Hamdi/F-4500-2012 OI Zhang, Dongxiao/0000-0001-6930-5994; NR 16 TC 21 Z9 21 U1 0 U2 3 PU SOC PETROLEUM ENG PI RICHARDSON PA 222 PALISADES CREEK DR,, RICHARDSON, TX 75080 USA SN 1086-055X J9 SPE J JI SPE J. PD MAR PY 2000 VL 5 IS 1 BP 60 EP 70 PG 11 WC Engineering, Petroleum SC Engineering GA 369WF UT WOS:000165090200009 ER PT J AU Alam, MK Alam, TM AF Alam, MK Alam, TM TI Multivariate analysis and quantitation of O-17-nuclear magnetic resonance in primary alcohol mixtures SO SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY LA English DT Article DE O-17-nuclear magnetic resonance; multivariate analysis; primary alcohols; net analyte signal ID LEAST-SQUARES ANALYSIS; SPECTRAL DATA SETS; SPECTROSCOPY; CALIBRATION AB Multivariate techniques were used to address the quantification of O-17-nuclear magnetic resonance (NMR) spectra for a series of primary alcohol mixtures. Due to highly overlapping resonances, quantitative spectral evaluation using standard integration and deconvolution techniques proved difficult. Multivariate evaluation of the O-17-NMR spectral data obtained for 26 mixtures of five primary alcohols demonstrated that obtaining information about spectral overlap and interferences allowed the development of more accurate models. Initial partial least squares (PLS) models developed for the O-17-NMR data collected from the primary alcohol mixtures resulted in very poor precision, with signal overlap between the different chemical species suspected of being the primary contributor to the error. To directly evaluate the question of spectral overlap in these alcohol mixtures, net analyte signal (NAS) analyses were performed. The NAS results indicate that alcohols with similar chain lengths produced severely overlapping O-17-NMR resonances. Grouping the alcohols based on chain length allowed more accurate and robust calibration models to be developed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Mat & Proc Computat & Modeling Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Organ Mat Aging & Reliabil Dept, Albuquerque, NM 87185 USA. RP Alam, MK (reprint author), Sandia Natl Labs, Mat & Proc Computat & Modeling Dept, MS 0342, Albuquerque, NM 87185 USA. NR 19 TC 7 Z9 7 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1386-1425 J9 SPECTROCHIM ACTA A JI Spectroc. Acta Pt. A-Molec. Biomolec. Spectr. PD MAR PY 2000 VL 56 IS 4 BP 729 EP 738 DI 10.1016/S1386-1425(99)00176-6 PG 10 WC Spectroscopy SC Spectroscopy GA 294KH UT WOS:000085910100009 PM 10794447 ER PT J AU Vallet, CE Prouteau, CS Feenstra, R Hamet, JF Verebelyi, DT Christen, DK AF Vallet, CE Prouteau, CS Feenstra, R Hamet, JF Verebelyi, DT Christen, DK TI Atomic force microscopy study of bicrystal SrTiO3 substrates and YBCO thin films SO SURFACE AND INTERFACE ANALYSIS LA English DT Article; Proceedings Paper CT Surface Analysis 99 Topical Conference of the American-Vacuum-Society CY JUN 14-17, 1999 CL WAUKESHA, WISCONSIN SP Amer Vacuum Soc, Appl Surface Sci Div, Prairie, MN & WI Chapters AVS DE AFM; bicrystal; substrate; SrTiO3; YBCO ID SCANNING TUNNELING MICROSCOPY; EPITAXIAL YBA2CU3O7-X FILMS; SINGLE GRAIN-BOUNDARIES; GROWTH-MECHANISM; SUPERCONDUCTING FILMS; SURFACE; MICROSTRUCTURE; PHASE; FLUX AB Single-crystal substrates allow the epitaxial deposition of high-T-c superconductor (HTS) films that exhibit high critical current densities (J(c)), The decrease in J(c) observed for films deposited on polycrystalline crystals is attributed to misorientation between adjacent grains. To understand better this phenomenon, deposition of HTS films on bicrystal substrates is used to model the effects of a single grain boundary. The surfaces of strontium titanate (001) bicrystals with tilt boundary orientations of 7 degrees, 15 degrees and 24 degrees were analyzed by atomic force microscopy (AFM), Annealing conditions were found to be a key factor for obtaining atomically smooth surfaces. The grain boundary morphologies were analyzed from sections of the AFM images. Images of YBa2Cu3O7-x (YBCO) films produced on these substrates by pulsed-laser deposition are shown for regions that include the grain boundaries. Different morphologies of YBCO thin films are presented. Copyright (C) 2000 John Wiley & Sons, Ltd. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. ISMRA, Lab Cristallog & Sci Mat, F-14050 Caen, France. RP Vallet, CE (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Bldg 4500N,MS 6197,POB 2008, Oak Ridge, TN 37831 USA. NR 34 TC 1 Z9 1 U1 2 U2 4 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0142-2421 J9 SURF INTERFACE ANAL JI Surf. Interface Anal. PD MAR PY 2000 VL 29 IS 3 BP 221 EP 226 PG 6 WC Chemistry, Physical SC Chemistry GA 298GK UT WOS:000086130800008 ER PT J AU Stanka, B Hebenstreit, W Diebold, U Chambers, SA AF Stanka, B Hebenstreit, W Diebold, U Chambers, SA TI Surface reconstruction of Fe3O4(001) SO SURFACE SCIENCE LA English DT Article DE iron oxide; low energy electron diffraction (LEED); low energy ion scattering (LEIS); low index single crystal surface; magnetic surfaces; scanning tunneling microscopy; surface relaxation and reconstruction; X-ray photoelectron spectroscopy ID MOLECULAR-BEAM EPITAXY; SCANNING-TUNNELING-MICROSCOPY; THIN-FILMS; GROWTH; TRANSITION AB We have investigated the surface termination, structure, morphology and composition of Fe3O4(001) using scanning tunneling microscopy (STM), low-energy electron diffraction (LEED), low-energy He+-ion scattering (LEIS) and X-ray photoelectron spectroscopy (XPS). The samples consisted of similar to 5000 Angstrom thick epitaxial films of Fe3O4(001) grown by oxygen-plasma-assisted molecular-beam epitaxy (OPA-MBE) on MgO(001) substrates. The (root 2 x root 2)R45 degrees surface reconstruction that is present on the as-grown surface is recovered by heating the sample in oxygen (10(-6)-10(-7) mbar) at temperatures between 420 and 770 K after a through-air transfer from the MBE chamber. STM results are best interpreted by assuming an autocompensated B-layer termination, which consists of a layer of octahedrally coordinated iron and tetrahedrally coordinated oxygen, along with one oxygen vacancy per unit cell. Evidence for a vacancy-induced lateral relaxation of the adjacent octahedral iron ions is presented. Further annealing in ultrahigh vacuum causes a transformation to either a (1 x n) or a (2 root 2 x root 2)R45 degrees structure. These surfaces can be reproducibly transformed back to the (root 2 x root 2)R45 degrees reconstruction by annealing in oxygen. Interestingly, at no time do we observe the other autocompensated termination, which consists of one-half of a monolayer of tetrahedrally coordinated Fe(III), despite its observation on the as-grown surface. Thus, it appears that the surface termination is critically dependent on the method of surface preparation. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Tulane Univ, Dept Phys, New Orleans, LA 70118 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Diebold, U (reprint author), Tulane Univ, Dept Phys, New Orleans, LA 70118 USA. RI Diebold, Ulrike/A-3681-2010 OI Diebold, Ulrike/0000-0003-0319-5256 NR 26 TC 108 Z9 109 U1 1 U2 35 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAR 1 PY 2000 VL 448 IS 1 BP 49 EP 63 DI 10.1016/S0039-6028(99)01182-6 PG 15 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 290CH UT WOS:000085658400010 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 brain nicotinic acetylcholine receptors by nicotine doses equivalent to those obtained when smoking a cigarette SO SYNAPSE LA English DT Article DE nicotinic acetylcholine receptors; nicotine; tobacco dependence; epibatidine; fluorine-18; positron emission tomography ID BINDING; PET C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. SUNY Stony Brook, Hlth Sci Ctr, Dept Psychiat, Stony Brook, NY 11794 USA. RP Ding, YS (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. FU NIDA NIH HHS [DA06278]; NINDS NIH HHS [NS15380] NR 15 TC 22 Z9 22 U1 0 U2 1 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-4476 J9 SYNAPSE JI Synapse PD MAR 1 PY 2000 VL 35 IS 3 BP 234 EP 237 DI 10.1002/(SICI)1098-2396(20000301)35:3<234::AID-SYN9>3.0.CO;2-7 PG 4 WC Neurosciences SC Neurosciences & Neurology GA 277FR UT WOS:000084922500009 PM 10657031 ER PT J AU Perez, D Siesel, BA Malaska, MJ David, E Vollhardt, KPC AF Perez, D Siesel, BA Malaska, MJ David, E Vollhardt, KPC TI Stereoselective cobalt-mediated [2+2+2]cycloadditions to the benzofuran nucleus: A novel strategy towards the synthesis of morphinoids SO SYNLETT LA English DT Article DE alkynes; benzofurans; cobalt; cycloadditions; morphine ID FORMAL TOTAL SYNTHESIS; OPIUM-ALKALOIDS; ASYMMETRIC-SYNTHESIS; PRACTICAL SYNTHESIS; 2,3-DOUBLE BOND; CYCLIZATION; ALKYNES; CONSTRUCTION; COMPLEXES; (+)-MORPHINE AB The cobalt-mediated [2+2+2]cycloaddition of alkynes to heteroaromatic double bonds can be extended to the benzofuran nucleus, suggesting applications to the synthesis of morphinoids. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Vollhardt, KPC (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Perez, Dolores/J-6588-2015; OI Perez, Dolores/0000-0003-0877-5938; Malaska, Michael/0000-0003-0064-5258 NR 42 TC 26 Z9 26 U1 0 U2 2 PU GEORG THIEME VERLAG KG PI STUTTGART PA RUDIGERSTR 14, D-70469 STUTTGART, GERMANY SN 0936-5214 J9 SYNLETT JI Synlett PD MAR PY 2000 IS 3 BP 306 EP 310 PG 5 WC Chemistry, Organic SC Chemistry GA 300LM UT WOS:000086254500003 ER PT J AU Poet, TS Thrall, KD Corley, RA Hui, XY Edwards, JA Weitz, KK Maibach, HI Wester, RC AF Poet, TS Thrall, KD Corley, RA Hui, XY Edwards, JA Weitz, KK Maibach, HI Wester, RC TI Utility of real time breath analysis and physiologically based pharmacokinetic modeling to determine the percutaneous absorption of methyl chloroform in rats and humans SO TOXICOLOGICAL SCIENCES LA English DT Article DE methyl chloroform; percutaneous absorption; permeability coefficients; physiologically based pharmacokinetic model ID VOLATILE ORGANIC-CHEMICALS; DERMAL ABSORPTION; PARTITION-COEFFICIENTS; EXPOSURE; WATER; SKIN; ROUTE; PENETRATION; METABOLISM AB Due to the large surface area of the skin, percutaneous absorption has the potential to contribute significantly to the total bioavailability of some compounds. Breath elimination data, acquired in real-time using a novel MS/MS system, was assessed using a PBPK model with a dermal compartment to determine the percutaneous absorption of methyl chloroform (MC) in rats and humans from exposures to MC in non-occluded soil or occluded water matrices. Rats were exposed to MC using a dermal exposure cell attached to a clipper-shaved area on their back. The soil exposure cell was covered with a charcoal patch to capture volatilized MC and prevent contamination of exhaled breath. This technique allowed the determination of MC dermal absorption kinetics under realistic, non-occluded conditions. Human exposures were conducted by immersing one hand in 0.1% MC in water, or 0.751 MC in soil. The dermal PBPK model was used to estimate skin permeability (K-P) based on the fit of the exhaled breath data. Rat skin K(P)s were estimated to be 0.25 and 0.15 cm/h for MC in water and soil matrices, respectively. In comparison, human permeability coefficients for water matrix exposures were 40-fold lower at 0.006 cm/h. Due to evaporation and differences in apparent K-P, nearly twice as much MC was absorbed from the occluded water (61.3%) compared to the non-occluded soil (32.5%) system in the rat. The PBPK model was used to simulate dermal exposures to MC-contaminated water and soil in children and adults using worst-case EPA default assumptions. The simulations indicate that neither children nor adults will absorb significant amounts of MC from non-occluded exposures, independent of the length of exposure. The results from these simulations reiterate the importance of conducting dermal exposures under realistic conditions. C1 Battelle, Pacific NW Div, Chem Dosimetry, Richland, WA 99352 USA. Univ Calif San Francisco, Dept Dermatol, San Francisco, CA 94143 USA. RP Poet, TS (reprint author), Battelle, Pacific NW Div, Chem Dosimetry, POB 999 MSIN P7-59, Richland, WA 99352 USA. NR 30 TC 28 Z9 29 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 1096-6080 J9 TOXICOL SCI JI Toxicol. Sci. PD MAR PY 2000 VL 54 IS 1 BP 42 EP 51 DI 10.1093/toxsci/54.1.42 PG 10 WC Toxicology SC Toxicology GA 292MU UT WOS:000085799400005 PM 10746930 ER PT J AU Saghir, SA Hansen, LG Holmes, KR Kodavanti, PRS AF Saghir, SA Hansen, LG Holmes, KR Kodavanti, PRS TI Differential and non-uniform tissue and brain distribution of two distinct C-14-hexachlorobiphenyls in weanling rats SO TOXICOLOGICAL SCIENCES LA English DT Article DE brain; polychlorinated biphenyl (PCB); neurotoxicity; structure-specific brain accumulation; 2,2 ',4,4 ',5,5 '-hexachlorobiphenyl; 3,3 ',4,4 ',5,5 '-hexachlorobiphenyl; PCB distribution; PCB excretion ID POLYCHLORINATED BIPHENYL MIXTURES; SUBSTITUTED PCB CONGENERS; PREPUBERTAL FEMALE RATS; ACUTE EXPOSURE; NEUROTOXICITY; SEQUESTRATION; INDUCTION; RESPONSES; BINDING; ISOMERS AB Excretion and tissue retention of a coplanar and a non-coplanar hexachlorobiphenyl (HxCB) were determined 48 h after a single intraperitoneal (ip) dose of 8 mg/kg radiolabeled [C-14]-HxCBs to weanling male and female Long-Evans rats. The objective was to understand the involvement of initial target organs of chlorobiphenyl (CB) accumulation following acute exposure in immature animals. During the short interval, both HxCBs remained sequestered predominantly in mesenteric fat (compared to subcutaneous fat) and less than 1% of the doses were excreted. Excretion was 4- to 8-fold lower than adult rats. Coplanar CB 169 (3,3', 4,4', 5,5'-HxCB) did not accumulate appreciably in the brain, but was retained at 3-fold higher levels in the liver than was non-coplanar CB 153 (2,2', 4,4', 5,5'-HxCB). Accumulation of C-14-CB 153 in brains was 4- to 9-fold higher than that of C-14-CB 169 and was adequate to detect non-uniform distribution in serial cryostat sections by phosphor imaging autoradiography. The autoradiographs showed a higher CB 153-derived radioactivity associated with fiber tracts throughout the brain. Specifically, the corpus callosum, internal and external capsules, medial lemniscus, tegmentum of the mesencephalon and metencephalon, and cerebellar peduncles showed significantly higher C-14-CB 153 than the other structures. The 14C-CB 153 was not found in the ventricular system and vascular spaces. These results suggest for the first time that an ortho-substituted PCB congener accumulated preferentially in brain in a structure-specific manner when compared to a non-ortho-substituted PCB congener. C1 US EPA, Cellular & Mol Toxicol Branch, Div Neurotoxicol, Natl Hlth & Environm Effects Res Lab, Res Triangle Pk, NC 27711 USA. Univ Illinois, Dept Vet Biosci, Urbana, IL 61802 USA. RP Saghir, SA (reprint author), Pacific NW Lab, POB 999,Mail Stop P7-56, Richland, WA 99352 USA. NR 46 TC 28 Z9 29 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 1096-6080 J9 TOXICOL SCI JI Toxicol. Sci. PD MAR PY 2000 VL 54 IS 1 BP 60 EP 70 DI 10.1093/toxsci/54.1.60 PG 11 WC Toxicology SC Toxicology GA 292MU UT WOS:000085799400007 PM 10746932 ER PT J AU Luan, P Heine, A Zeng, K Moyer, B Greasely, SE Kuhn, P Balch, WE Wilson, IA AF Luan, P Heine, A Zeng, K Moyer, B Greasely, SE Kuhn, P Balch, WE Wilson, IA TI A new functional domain of guanine nucleotide dissociation inhibitor (alpha-GDI) involved in Rab recycling SO TRAFFIC LA English DT Article DE fusion; GDI; Rab; transport; vesicle ID GTP-BINDING PROTEIN; MEMBRANE ASSOCIATION; MENTAL-RETARDATION; SECRETORY PATHWAY; BOVINE BRAIN; IN-VIVO; YEAST; TRANSFORMATION; GTPASES; GOLGI AB Guanine nucleotide dissociation inhibitor (GDI) is a 55-kDa protein that functions in vesicular membrane transport to recycle Rab GTPases. We have now determined the crystal structure of bovine alpha-GDI at ultra-high resolution (1.04 Angstrom). Refinement at this resolution highlighted a region with high mobility of its main-chain residues. This corresponded to a surface loop in the primarily at-helical domain II at the base of alpha-GDI containing the previously uncharacterized sequence-conserved region (SCR) 3A. Site-directed mutagenesis showed that this mobile loop plays a crucial role in binding of GDI to membranes and extraction of membrane-bound Rab. This domain, referred to as the mobile effector loop, in combination with Rab-binding residues found in the multi-sheet domain I at the apex of alpha-GDI may provide flexibility for recycling of diverse Rab GTPases. We propose that conserved residues in domains I and II synergize to form the functional face of GDI, and that domain II mediates a critical step in Rab recycling during vesicle fusion. C1 Scripps Res Inst, Res Inst, Dept Mol Biol, La Jolla, CA 92037 USA. Scripps Res Inst, Res Inst, Dept Cell Biol, La Jolla, CA 92037 USA. Scripps Res Inst, Res Inst, Skaggs Inst Chem Biol, La Jolla, CA 92037 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Balch, WE (reprint author), Scripps Res Inst, Res Inst, Dept Mol Biol, 10550 N Torrey Pines Rd, La Jolla, CA 92037 USA. FU NIGMS NIH HHS [GM33301, GM49497] NR 44 TC 31 Z9 33 U1 1 U2 3 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 1398-9219 J9 TRAFFIC JI Traffic PD MAR PY 2000 VL 1 IS 3 BP 270 EP 281 DI 10.1034/j.1600-0854.2000.010309.x PG 12 WC Cell Biology SC Cell Biology GA 325ZB UT WOS:000087706200009 PM 11208110 ER PT J AU Coutant, CC Whitney, RR AF Coutant, CC Whitney, RR TI Fish behavior in relation to passage through hydropower turbines: A review SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Review ID ATLANTIC SALMON SMOLTS; COLUMBIA RIVER; SALAR L; MIGRATION; ANIMALS; SYSTEM; SIZE; DAM AB We evaluated the literature on fish behavior as it relates to passage of fish near or through hydropower turbines. Our goal was to foster compatibility of engineered systems with the normal behavior patterns of fish species and life stages such that passage into turbines and injury in passage are minimized. In particular, we focused on aspects of fish behavior that could be used for computational fluid dynamics (CFD) modeling of fish trajectories through turbine systems. Salmon smolts approaching dams are generally surface oriented and follow flow. They can be diverted from turbines by spills or bypasses, with varying degrees of effectiveness. Smolts typically become disoriented in dam forebays. Those smolts drawn into turbine intakes orient vertically to the ceilings bur are horizontally distributed more evenly, except as they are affected by intake-specific turbulence and vortices. Smolts often enter intakes while oriented with their heads upstream, but they may change orientation in the flow fields of the intake. Nonsalmonids most often enter intakes from the vicinities of shorelines, and they do so episodically, which suggests accidental capture of schools (often of juveniles or in cold water) and little behavioral control during turbine passage. Models of fish trajectories should not assume neutral buoyancy throughout the time period during which a fish passes through a turbine, largely because of pressure effects on swim bladders and the resulting compensatory behavior. Fish use their lateral line system to sense obstacles and to change their orientation, but this sensory-response system may not be effective in the rapid passage times and complex pressure regimes of turbine systems. The effects of preexisting stress levels on fish performance in turbine passage (especially as they affect trajectories) are not known but may be important. There are practical limits of observation and measurement of fish and hows in the proximity of turbines that may inhibit the development of much information that is germane to developing a more fish-friendly turbine. We provide recommendations for CFD modelers of fish passage and for additional research. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Coutant, CC (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 136 TC 142 Z9 147 U1 12 U2 87 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD MAR PY 2000 VL 129 IS 2 BP 351 EP 380 DI 10.1577/1548-8659(2000)129<0351:FBIRTP>2.0.CO;2 PG 30 WC Fisheries SC Fisheries GA 342GB UT WOS:000088635900003 ER PT J AU Johnson, GE Adams, NS Johnson, RL Rondorf, DW Dauble, DD Barila, TY AF Johnson, GE Adams, NS Johnson, RL Rondorf, DW Dauble, DD Barila, TY TI Evaluation of the prototype surface bypass for salmonid smolts in spring 1996 and 1997 at Lower Granite Dam on the Snake River, Washington SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID COLUMBIA RIVER; WELLS DAM; PASSAGE; BEHAVIOR AB In spring 1996 and 1997, we studied the prototype surface bypass and collector (SBC) at Lower Granite Dam on the Snake River in Washington. Our objectives were to determine the most efficient SBC configuration and to describe smolt movements and swimming behavior in the forebay. To do this, we used hydroacoustic and radiotelemetry techniques. The SBC was retrofitted onto the upstream face of the north half of the powerhouse to test the surface bypass method of diverting smolts from turbines. The SBC had three entrances, with mean velocities ranging from 0.37 to 1.92 m/s, and it discharged 113 m(3)/s through its outlet at Spill Bay I, which was adjacent to the powerhouse. Different SBC configurations were created by altering the size and shape of entrances. During spring 1996 and 1997, river discharge was well above normal (123 and 154% of average, respectively). Powerhouse operations caused a strong downward component of flow upstream of the SBC. Many smolts (primarily steelhead and secondarily chinook salmon) were observed actively swimming upward in the water column. There were four times as many smolts diverted from turbines per unit volume of water with SBC flow than with spill flow, which indicated that the SBC may be an especially important bypass consideration in moderate- or low-flow years. The highest SBC efficiency (the proportion of total fish passing through the north half of the powerhouse by all routes that passed through the SEC) for any configuration tested was about 40%. Although no single SBC configuration stood out as the most efficient, the horizontal surface and maximum area configurations, or some combination of the two. are worth further investigation because they were moderately efficient. C1 Battelles Pacific NW Div, Richland, WA 99352 USA. US Geol Survey, Biol Resources Div, Cook, WA 98605 USA. USA, Corps Engineers, Walla Walla, WA 99362 USA. RP Johnson, GE (reprint author), BioAnalysts Inc, 11807 NE 99th St,Suite 1160, Vancouver, WA 98682 USA. NR 31 TC 34 Z9 34 U1 1 U2 8 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD MAR PY 2000 VL 129 IS 2 BP 381 EP 397 DI 10.1577/1548-8659(2000)129<0381:EOTPSB>2.0.CO;2 PG 17 WC Fisheries SC Fisheries GA 342GB UT WOS:000088635900004 ER PT J AU Oldenburg, CM Borglin, SE Moridis, GJ AF Oldenburg, CM Borglin, SE Moridis, GJ TI Numerical simulation of ferrofluid flow for subsurface environmental engineering applications SO TRANSPORT IN POROUS MEDIA LA English DT Article DE ferrofluids; magnetic fluids; subsurface barrier verification; magneto pressure; numerical simulation ID NONAQUEOUS PHASE LIQUIDS; STEAM INJECTION; TRANSPORT; REMOVAL AB Ferrofluids are suspensions of magnetic particles of diameter approximately 10 nm stabilized by surfactants in carrier liquids. The large magnetic susceptibility of ferrofluids allows the mobilization of ferrofluid through permeable rock and soil by the application of strong external magnetic fields. We have developed simulation capabilities for both miscible and immiscible conceptualizations of ferrofluid flow through porous media in response to magnetic forces arising from the magnetic field of a rectangular permanent magnet. The flow of ferrofluid is caused by the magnetization of the particles and their attraction toward a magnet, regardless of the orientation of the magnet. The steps involved in calculating the flow of ferrofluid are (1) calculation of the external magnetic field, (2) calculation of the gradient of the external magnetic field, (3) calculation of the magnetization of the ferrofluid, and (4) assembly of the magnetic body force term and addition of this term to the standard pressure gradient and gravity force terms. We compare numerical simulations to laboratory measurements of the magnetic field, fluid pressures, and the two-dimensional flow of ferrofluid to demonstrate the applicability of the methods coded in the numerical simulators. We present an example of the use of the simulator for a field-scale application of ferrofluids for barrier verification. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Oldenburg, CM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RI Oldenburg, Curtis/L-6219-2013; Borglin, Sharon/I-1013-2016 OI Oldenburg, Curtis/0000-0002-0132-6016; NR 28 TC 44 Z9 45 U1 0 U2 10 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0169-3913 J9 TRANSPORT POROUS MED JI Transp. Porous Media PD MAR PY 2000 VL 38 IS 3 BP 319 EP 344 DI 10.1023/A:1006611702281 PG 26 WC Engineering, Chemical SC Engineering GA 279GJ UT WOS:000085035800005 ER PT J AU Michael, JR Eades, JA AF Michael, JR Eades, JA TI Use of reciprocal lattice layer spacing in electron backscatter diffraction pattern analysis SO ULTRAMICROSCOPY LA English DT Article DE electron diffraction; scanning electron microscopy; electron backscattering diffraction ID KIKUCHI-DIFFRACTION AB In the scanning electron microscope using electron backscattered diffraction, it is possible to measure the spacing of the layers in the reciprocal lattice. These values are of great use in confirming the identification of phases. The technique derives the layer spacing from the higher-order Laue zone rings which appear in patterns from many materials. The method adapts results from convergent-beam electron diffraction in the transmission electron microscope. For many materials the measured layer spacing compares well with the calculated layer spacing. A noted exception is for higher atomic number materials. In these cases an extrapolation procedure is described that requires layer spacing measurements at a range of accelerating voltages. This procedure is shown to improve the accuracy of the technique significantly. The application of layer spacing measurements in EBSD is shown to be of use for the analysis of two polytypes of SIG. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Lehigh Univ, Dept Mat Sci & Engn, Bethlehem, PA 18015 USA. RP Michael, JR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 14 TC 29 Z9 30 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD MAR PY 2000 VL 81 IS 2 BP 67 EP 81 DI 10.1016/S0304-3991(99)00119-9 PG 15 WC Microscopy SC Microscopy GA 437VN UT WOS:000169014400005 ER PT J AU Boopathy, R Manning, JF AF Boopathy, R Manning, JF TI Laboratory treatability study on hexahydro-1,3,5-trinitro-1,3,5-triazine-(RDX-) contaminated soil from the Iowa Army Ammunition Plant, Burlington, Iowa SO WATER ENVIRONMENT RESEARCH LA English DT Article DE RDX; contamination; co-metabolism; cosubstrate; molasses; soil-slurry reactor; bioremediation; explosives ID SP B-STRAIN; 2,4,6-TRINITROTOLUENE TNT; MICROBIAL TRANSFORMATION; NITROAROMATIC COMPOUNDS; AEROBIC CONDITIONS; BIOREMEDIATION; METABOLISM; EXPLOSIVES AB Soil in certain areas of the Iowa Army Ammunition Plant in Burlington. Iowa, was contaminated with hexahydro-1,3,5-trinitro- 1,3,5-triazine (RDX). A laboratory treatability study was conducted to examine the ability of native soil bacteria present in the contaminated sire to degrade RDX. The results indicated that RDX can be removed effectively From the soil by native soil bacteria through a co-metabolic process. Molasses, identified as an effective cosubstrate, is inexpensive, and this Factor makes the treatment system cost effective. The successful operation of aerobic-anoxic soil-slurry reactors in batch mode with RDX-contaminated soil showed that the technology can be scaled up for field demonstration. The RDX concentration in the contaminated soil was decreased by 98% after 4 months of reactor operation. The advantage of the slurry reactor is the simplicity of its operation. The method needs only mixing and the addition of molasses as cosubstrate. C1 Nicholls State Univ, Dept Biol Sci, Thibodaux, LA 70310 USA. Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. RP Boopathy, R (reprint author), Nicholls State Univ, Dept Biol Sci, Thibodaux, LA 70310 USA. NR 28 TC 17 Z9 19 U1 1 U2 2 PU WATER ENVIRONMENT FEDERATION PI ALEXANDRIA PA 601 WYTHE ST, ALEXANDRIA, VA 22314-1994 USA SN 1061-4303 J9 WATER ENVIRON RES JI Water Environ. Res. PD MAR-APR PY 2000 VL 72 IS 2 BP 238 EP 242 DI 10.2175/106143000X137400 PG 5 WC Engineering, Environmental; Environmental Sciences; Limnology; Water Resources SC Engineering; Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 300EM UT WOS:000086239900017 ER PT J AU Liu, HH Bodvarsson, GS Pan, L AF Liu, HH Bodvarsson, GS Pan, L TI Determination of particle transfer in random walk particle methods for fractured porous media SO WATER RESOURCES RESEARCH LA English DT Article ID SOLUTE TRANSPORT; SIMULATION; GROUNDWATER AB A commonly used numerical scheme to simulate solute transport in the subsurface is the random walk particle method (RWPM). While significant progress has been made in developing random walk particle algorithms for porous media, an RWPM for fractured porous media, represented by dual continua, has not yet been developed in the literature. A key issue in developing an RWPM for fractured porous media is the determination of particle transfer between the two continua. In this study a relatively simple, yet physically based scheme to determine the particle transfer is developed. The usefulness of the scheme is demonstrated by comparing solute transport results determined from the proposed scheme with (1) an analytical solution for solute transport in a fractured porous medium with parallel fractures and (2) a numerical simulation obtained using the TOUGH2 code, a simulator for multiphase and multicomponent flow and transport in fractured porous media. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Liu, HH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, MS 90-1116, Berkeley, CA 94720 USA. RI Pan, Lehua/G-2439-2015 NR 18 TC 25 Z9 26 U1 0 U2 1 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 MAR PY 2000 VL 36 IS 3 BP 707 EP 713 DI 10.1029/1999WR900323 PG 7 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 287RL UT WOS:000085519700006 ER PT J AU Sun, AY Zhang, DX AF Sun, AY Zhang, DX TI Prediction of solute spreading during vertical infiltration in unsaturated, bounded heterogeneous porous media SO WATER RESOURCES RESEARCH LA English DT Article ID HEAD SPATIAL VARIABILITY; TRANSFER-FUNCTION MODEL; STEADY-STATE FLOW; STOCHASTIC-ANALYSIS; FIELD SCALE; TRANSPORT; SOIL; AQUIFERS; SIMULATION; DISPERSION AB In this study we investigate the effect of a water table boundary on solute spreading during infiltration in the vadose zone of heterogeneous soils. It has been found recently that the presence of the water table significantly affects unsaturated flow in a heterogeneous vadose zone and causes the flow to be spatially nonstationary. Because a vadose zone is by definition bounded by the water table at the bottom and the contaminants present in the vadose zone migrate into the groundwater through the water table, it is of great interest to study the behaviors of a solute plume near the water table and the effects of how nonstationarity caused by the water table on solute spreading. To do so, we develop a Lagrangian stochastic approach for predicting field-scale solute spreading in a spatially nonstationary velocity field. Through first-order approximations the statistical moments of particle displacement are related to the moments of the Eulerian velocity field. Closed form expressions are obtained for the special case of unidirectional but nonuniform mean flow such as vertical infiltration. We illustrate our theoretical developments with some one-dimensional examples of solute transport during steady state infiltration in bounded vadose zones. It is found that the inclusion of the water table significantly impacts the behaviors of the mean particle displacement and the displacement covariance, which quantify expected solute displacement and spreading about the expected value, respectively. At late times the particle displacement covariance: is generally much smaller when the effect of the water table is included than when it is neglected. In particular, for the case of one-dimensional infiltration in a bounded vadose zone the particle displacement covariance decreases with time at late times. This finding is in contrast to the result that the particle displacement covariance increases linearly at late times as found by previous stochastic studies of solute transport in unbounded vadose zones. Hence macrodispersion may be greatly overestimated in previous stochastic studies that disregarded the presence of the water table. The validity of the theoretical approach developed in this paper is investigated and confirmed by Monte Carlo simulations. C1 Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. Los Alamos Natl Lab, Geoanal Grp, Los Alamos, NM 87545 USA. RP Sun, AY (reprint author), Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. EM sun@alpha-6.ce.berkeley.edu; dzhang@vega.lanl.gov RI Zhang, Dongxiao/D-5289-2009; Sun, Alexander/A-9959-2011 OI Zhang, Dongxiao/0000-0001-6930-5994; NR 29 TC 11 Z9 11 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 EI 1944-7973 J9 WATER RESOUR RES JI Water Resour. Res. PD MAR PY 2000 VL 36 IS 3 BP 715 EP 723 DI 10.1029/1999WR900344 PG 9 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 287RL UT WOS:000085519700007 ER PT J AU Wu, YS AF Wu, YS TI A virtual node method for handling well bore boundary conditions in modeling multiphase flow in porous and fractured media SO WATER RESOURCES RESEARCH LA English DT Article ID SUBSURFACE AB How to treat well boundary conditions is a difficult issue when formulating and coding a multiphase numerical reservoir simulator. The difficulty arises because the partial differential equation governing multiphase subsurface how is of a mixed parabolic-hyperbolic type. Maximum changes in primary variables and mass/heat fluxes occur at boundaries or well nodes. Consequently, these well nodes with small volume tend to be singular, leading to computational convergence problems. The conventional method of well treatment in geothermal or oil reservoir simulators is to use a sink/source term approach and to distribute flow rates by a potential or mobility allocation scheme for a multilayered well. However, this traditional method cannot handle a backflow problem, which may occur in a multilayered well in heterogeneous formations. This paper presents a "virtual node" method to handle a well bore either as a single node or several computational nodes screened and connected to many neighboring nodes for a multilayered well. The well bore can be vertical, inclined, or horizontal, and the well borehole node is treated in the same way as any other nonwell node for flow calculations. The solution at the well is then obtained by solving mass balance equations for the well node. It is shown that the new method provides a natural, physically consistent, and numerically efficient approach to handling well flow problems. Implementation of this new method for a three-phase flow reservoir simulator is discussed, and three examples are provided. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Wu, YS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, MS 90-1116,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Wu, Yu-Shu/A-5800-2011 NR 18 TC 15 Z9 15 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAR PY 2000 VL 36 IS 3 BP 807 EP 814 DI 10.1029/1999WR900336 PG 8 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 287RL UT WOS:000085519700018 ER PT J AU Dumont, B Blau, PJ Crosbie, GM AF Dumont, B Blau, PJ Crosbie, GM TI Reciprocating friction and wear of two silicon nitride-based ceramics against type 316 stainless steel SO WEAR LA English DT Article DE friction; wear; ceramic-matrix composites; silicon nitride; silver additives; oil additives ID LUBRICATED CONDITIONS; SI3N4-TIC COMPOSITES; MINERAL-OIL; BEHAVIOR; PAIRS; DRY; TEMPERATURES; ROUGHNESS; CONTACTS; WHISKER AB Reciprocating ball-on-flat tests were conducted to assess the relative friction and wear behavior of two silicon nitride (Si3N4)-based materials under lubricated conditions. One of these ceramic materials was produced by a commercial supplier and is designated NT-451. The other was an experimental ceramic composite with a composition of 4.2 wt.% Y2O3, (sintering aid), 2.1 wt.% Al2O3 (sintering aid), 8.5 wt.%, SiC whiskers, 39.1 wt.% TiC, with the balance Si3N4. The standard slider (ball) material was type 316 stainless steel. Tests were conducted with two liquid lubricants at room temperature and at 170 degrees C. The first lubricant was a commercial 30-weight viscosity diesel oil and the second was a special oil formulation to which silver compounds had been added. Steady state kinetic friction coefficients( mu) for both ceramics lubricated with both oils averaged approximately 0.12 at room temperature. At elevated temperature, mu ranged from about 0.06 to 0.16, depending on the lubricant. Lubricated wear rates of the ceramic materials tended to be lower for the composite (3 x 10(-8) mm(3)/N m) than for the NT-451 (1.5 x 10(-7) mm(3)/N m). Likewise, the wear of the stainless steel was lower against the composite than against the NT-451 (1 x 10(-7)-5 x 10(-7) and 0.5 x 10(-6)-3 x 10(-6) mm(3)/N m, respectively). These results suggest that silicon nitride materials can be made more compatible (in terms of wear and friction) with metallic counterfaces in reciprocating wear situations by the judicious selection of additions. No clear and significant effects of Ag particles in the oil were observed in the friction or wear data for either ceramic-stainless steel couple. (C) 2000 Published by Elsevier Science S.A. All rights reserved. C1 Oak Ridge Inst Sci & Educ, Oak Ridge, TN 37830 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Ford Motor Co, Res Lab, Dearborn, MI 48121 USA. RP Dumont, B (reprint author), Oak Ridge Inst Sci & Educ, Oak Ridge, TN 37830 USA. NR 36 TC 9 Z9 9 U1 2 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD MAR PY 2000 VL 238 IS 2 BP 93 EP 109 DI 10.1016/S0043-1648(99)00320-8 PG 17 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 297NR UT WOS:000086089400002 ER PT J AU El-Raghy, T Blau, P Barsoum, MW AF El-Raghy, T Blau, P Barsoum, MW TI Effect of grain size on friction and wear behavior of Ti3SiC2 SO WEAR LA English DT Article DE grain size; wear; Ti3SiC2 ID SLIDING WEAR; CERAMICS; ALUMINA; MECHANISMS; CONTACT AB The effects of grain size on the sliding friction, sliding wear, and two-body abrasive wear behavior of Ti3SiC2 were investigated. Samples with two different grain sizes, namely, 5 mu m ('fine') and 100 mu m ('coarse'), were used as discs in pin-on-disc sliding wear tests against a 340C steel pin and as rectangular pins in diamond belt abrasion tests. In the pin-on-disc test, irrespective of the grain size, it was found that the material undergoes an initial transition stage where the friction coefficient, mu, increases linearly to 0.15 to 0.45. After this transition stage, mu rises to steady state values, of about 0.83 for both coarse- and the fine-grained materials. It was concluded that the transition from the low to high mu is due to accumulation of debris entrapped between the disc and the pin, resulting in third-body abrasion. The average sliding wear rates in the pin-on-disc tests were 4.25 x 10(-3) and 1.34 x 10(-3) mm(3)/N m for the fine and the coarse grains, respectively. In the diamond belt abrasion tests. the average wear rates were much higher: 6.14 x 10(-2) and 3.96 x 10(-2) mm(3)/N m for the fine and the coarse grains, respectively. In the fine-grained material, it was concluded that the wear mechanisms include grain pre-fracture and removal. Delamination, crack bridging, grain deformation, microcracking, and grain fracture are the operative wear mechanisms observed in the case of the coarse-grained material. It is this multitude of possible sliding energy dissipation mechanisms that is believed to enhance the wear resistance of the coarse-grained material relative to the fine-grained one. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Drexel Univ, Dept Mat Engn, Philadelphia, PA 19104 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP El-Raghy, T (reprint author), Drexel Univ, Dept Mat Engn, 32nd & Chestnut St, Philadelphia, PA 19104 USA. NR 17 TC 109 Z9 115 U1 1 U2 18 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD MAR PY 2000 VL 238 IS 2 BP 125 EP 130 DI 10.1016/S0043-1648(99)00348-8 PG 6 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 297NR UT WOS:000086089400005 ER PT J AU Dupont, JN Michael, JR Robino, CV AF Dupont, JN Michael, JR Robino, CV TI Using backscattered electron diffraction to understand weldability SO WELDING JOURNAL LA English DT Article ID SOLIDIFICATION MODE; WELDING METALLURGY; STAINLESS-STEELS AB The analysis technique can provide invaluable help in establishing the relationships between alloy composition, weld microstructure and weldability. C1 Lehigh Univ, Bethlehem, PA 18015 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Dupont, JN (reprint author), Lehigh Univ, Bethlehem, PA 18015 USA. NR 16 TC 4 Z9 4 U1 0 U2 0 PU AMER WELDING SOC PI MIAMI PA PO BOX 351040, MIAMI, FL 33135 USA SN 0043-2296 J9 WELD J JI Weld. J. PD MAR PY 2000 VL 79 IS 3 BP 43 EP 48 PG 6 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 290PT UT WOS:000085685200005 ER PT J AU McLeod, KW Reed, MR Wike, LD AF McLeod, KW Reed, MR Wike, LD TI Elevation, competition control, and species affect bottomland forest restoration SO WETLANDS LA English DT Article DE restoration; reforestation; competition; vegetation control; bottomland hardwood; swamp; southeastern United States AB This experiment examined how elevation and control of early successional vegetation would affect the growth and survival of tree species used in restoration. Vegetation was controlled by either mowing or spraying with Accord [glyphosate, -(phosphononomethyl)glycine, in the form of its isopropylamine salt] herbicide. These control methods were applied to either the entire plot or a narrow 1-m strip where seedlings were to be planted. A fifth treatment (control) had seedlings planted into the existing vegetation. Species planted were baldcypress (Taxodium distichum), water tupelo (Nyssa aquatica), willow oak (Quercus phellos), Nuttall oak (Q. nuttallii), overcup oak (e. lyrata), and cherrybark oak (Q. falcata var. pagodaefolia). Seedlings were randomly planted in late April 1993 with six rows in each plot and six trees per row on a 2 x 2 m spacing with five replicate plots per treatment. Survival was not enhanced by any competition control treatment, but survival among species differed. All six species had overall survival > 90% in autumn 1993. Species survival was affected by several summer floods during 1994. Baldcypress and overcup oak survival was greater than 89%, while water tupelo, Nuttall oak, and willow oak were all approximately 70%, and cherrybark oak was only 29%. By the end of 1995, survival of all species decreased further, but the species groupings remained the same. Survival and height growth of baldcypress and water tupelo were greatest at lower planting elevations. At higher elevations, survival of cherrybark oak and willow oak were greatest, while overcup oak and Nuttall oak were unaffected by elevation. Thus, controlling the herbaceous vegetation did not affect survival or growth as much as relative planting elevation due to site flooding and the flood tolerance of the species. All of the species in this experiment except cherrybark oak were successfully established. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29802 USA. RP McLeod, KW (reprint author), Univ Georgia, Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. NR 11 TC 8 Z9 9 U1 2 U2 11 PU SOC WETLAND SCIENTISTS PI LAWRENCE PA 810 E TENTH ST, P O BOX 1897, LAWRENCE, KS 66044 USA SN 0277-5212 J9 WETLANDS JI Wetlands PD MAR PY 2000 VL 20 IS 1 BP 162 EP 168 DI 10.1672/0277-5212(2000)020[0162:ECCASA]2.0.CO;2 PG 7 WC Ecology; Environmental Sciences SC Environmental Sciences & Ecology GA 298WJ UT WOS:000086162200014 ER PT J AU Hinderberger, S Dahmen, U Xiao, SQ Westmacott, KH AF Hinderberger, S Dahmen, U Xiao, SQ Westmacott, KH TI Shape refinement of Ge precipitates in an Al-Ge alloy by thermal cycling SO ZEITSCHRIFT FUR METALLKUNDE LA English DT Article ID MORPHOLOGY; GERMANIUM; EVOLUTION; ALUMINUM AB It is shown that the shape of Ge precipitates in quenched and aged AI-Ge alloys can be refined by a thermal cycling heat treatment which causes partial dissolution and regrowth of precipitates and leads to a shift in the distribution of precipitate morphologies. Using thermal cycling of material aged to contain precipitates in the cube-cube orientation relationship, it is shown that after several cycles of shrinkage and regrowth, the predominant precipitate shape is that of an octahedron. From direct in-situ observation in an electron microscope, the mechanism of shape refinement is found to be the elimination of internal twins. This conclusion is in agreement with earlier work, which showed that Ge precipitate shapes are controlled by twinning. For material aged to contain predominantly lath-shaped precipitates, thermal cycling does not lead to twin-free precipitates. This behavior can be understood from symmetry considerations. C1 Natl Ctr Electron Microscopy, LBNL, Berkeley, CA 94720 USA. RP Dahmen, U (reprint author), Natl Ctr Electron Microscopy, LBNL, Berkeley, CA 94720 USA. NR 18 TC 8 Z9 8 U1 0 U2 2 PU CARL HANSER VERLAG PI MUNICH PA KOLBERGERSTRASSE 22, POSTFACH 86 04 20, D-81679 MUNICH, GERMANY SN 0044-3093 J9 Z METALLKD JI Z. Metallk. PD MAR PY 2000 VL 91 IS 3 BP 215 EP 220 PG 6 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 305VK UT WOS:000086561100006 ER PT J AU Stone, ML Gresham, GL Polson, LA AF Stone, ML Gresham, GL Polson, LA TI Characterization of two polyphosphazene materials as membranes in membrane induction mass spectrometry SO ANALYTICA CHIMICA ACTA LA English DT Article DE mass spectrometry; membrane introduction interface; sample introduction ID VOLATILE ORGANIC-COMPOUNDS; FLOW-INJECTION ANALYSIS; ONLINE; WATER; FERMENTATION; SEPARATION; INTERFACE; SAMPLES; SYSTEM; MIMS AB Membrane introduction mass spectrometry (MIMS) has made large strides in capability improvement since its introduction. The main progress has been in systematic design changes that has allowed this technique to measure analytes in the parts-per-trillion range, samples that have had no special handling or pre-treatment. In spite of these improvements, however, the most important component of MIMS--the membrane--has not been optimized. In this paper, the results of testing two polyphosphazene polymers is reported and compared with those of silicone rubber. The results show that the rich chemical diversity possible with the phosphazene materials and their tailorability, make them good candidates for MIMS applications. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Stone, ML (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 37 TC 4 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0003-2670 J9 ANAL CHIM ACTA JI Anal. Chim. Acta PD FEB 29 PY 2000 VL 407 IS 1-2 BP 311 EP 317 DI 10.1016/S0003-2670(99)00834-X PG 7 WC Chemistry, Analytical SC Chemistry GA 285EZ UT WOS:000085377900034 ER PT J AU Moon, YU Anderson, CO Blanch, HW Prausnitz, JM AF Moon, YU Anderson, CO Blanch, HW Prausnitz, JM TI Osmotic pressures and second virial coefficients for aqueous saline solutions of lysozyme SO FLUID PHASE EQUILIBRIA LA English DT Article DE proteins; salts; intermolecular interactions; potentials of mean force; osmotic-pressure data; experimental method ID PROTEINS AB Experimental data at 25 degrees C are reported for osmotic pressures of aqueous solutions containing lysozyme and any one of the following salts: ammonium sulfate, ammonium oxalate, and ammonium phosphate at ionic strength 1 or 3 M. Data were obtained using a Wescor colloid membrane osmometer at lysozyme concentrations from about 4 to 20 g/l at pH 4, 7, or 8. Osmotic second virial coefficients for lysozyme were calculated from the osmotic-pressure data. All coefficients were negative, increasing in magnitude with ionic strength. Results are insensitive to the nature of the anion, but rise slightly in magnitude as the size of the anion increases. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Prausnitz, JM (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. NR 16 TC 51 Z9 54 U1 2 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3812 J9 FLUID PHASE EQUILIBR JI Fluid Phase Equilib. PD FEB 29 PY 2000 VL 168 IS 2 BP 229 EP 239 DI 10.1016/S0378-3812(99)00337-4 PG 11 WC Thermodynamics; Chemistry, Physical; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 299CV UT WOS:000086179000007 ER PT J AU Bidoia, ED McLarnon, F Cairns, EJ AF Bidoia, ED McLarnon, F Cairns, EJ TI Investigation of anion adsorption on platinum electrodes in aqueous media by probe beam deflection SO JOURNAL OF ELECTROANALYTICAL CHEMISTRY LA English DT Article DE adsorption; cyclic voltammetry; platinum; probe beam deflection ID SPECTROSCOPY; LAYERS AB Probe beam deflection (PBD) was used to monitor concentration gradients adjacent to the platinum electrode surface in basic and acidic aqueous media. It was observed that the PBD technique can detect anion adsorption on platinum during a cyclic voltammetry experiment. Also, PBD can measure the potential-dependent extent of adsorption of various anions including ClO4-, H2PO4- and Cl- on the Pt electrode surface. Published by Elsevier Science S.A. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Cairns, EJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, 1 Cyclotron Rd 70 1088, Berkeley, CA 94720 USA. RI Cairns, Elton/E-8873-2012 OI Cairns, Elton/0000-0002-1179-7591 NR 21 TC 16 Z9 16 U1 0 U2 3 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 FEB 29 PY 2000 VL 482 IS 1 BP 75 EP 80 DI 10.1016/S0022-0728(00)00003-6 PG 6 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA 327VD UT WOS:000087813900009 ER PT J AU Kotz, KT Yang, H Snee, PT Payne, CK Harris, CB AF Kotz, KT Yang, H Snee, PT Payne, CK Harris, CB TI Femtosecond infrared studies of ligand rearrangement reactions: silyl hydride products from Group 6 carbonyls SO JOURNAL OF ORGANOMETALLIC CHEMISTRY LA English DT Article DE IR spectroscopy; dissociative mechanism; dynamics; Group 6; ultrafast spectroscopy ID OCTAHEDRAL METAL-CARBONYLS; HYDROGEN BOND ACTIVATION; DISSOCIATION ENERGIES; TRANSIENT ABSORPTION; SOLVENT DISPLACEMENT; VIBRATIONAL-ENERGY; FLASH-PHOTOLYSIS; CO DISSOCIATION; NORMAL-HEPTANE; SPECTROSCOPY AB The ultrafast dynamics of the Si-H bond activation reaction by the Group 6 d(6) organometallic compounds M(CO)(5) (M = Cr, Mo, and W) have been studied in neat tri-substituted silanes under ambient conditions. The ultrafast spectral evolutions of the CO stretching bands were monitored following UV photolysis using femtosecond pump-probe spectroscopic methods. It was found that the coordinatively unsaturated species, which is formed following CO photolysis from the parent molecule, is quickly solvated (<2 ps) via the C-H bonds of the solvent. These species then rearranged to the silyl hydride product on a timescale of a few nanoseconds. These results were augmented by rearrangement studies in neat ethanol, propanol and hexanol solutions in which the initially formed metal C-H complex rearranged to the metal hydroxyl complex. The mechanism of this rearrangement was discussed by comparison of the data with various models in the literature. It was found that a mechanism that is primarily dissociative in nature provided the best description of the experimental data. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Ernest Orlando Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Harris, CB (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Payne, Christine/E-5954-2010 NR 52 TC 28 Z9 28 U1 0 U2 13 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-328X J9 J ORGANOMET CHEM JI J. Organomet. Chem. PD FEB 29 PY 2000 VL 596 IS 1-2 BP 183 EP 192 DI 10.1016/S0022-328X(99)00676-2 PG 10 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 294WE UT WOS:000085932800028 ER PT J AU Jones, RH Danielson, MJ AF Jones, RH Danielson, MJ TI Stress corrosion cracking of Type 304 stainless steel with mixed Mode I/III loading SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE stress corrosion cracking; type 304 stainless steel; mode I/III loading ID PURITY ROTOR STEEL; FRACTURE-TOUGHNESS; ALLOY; HYDROGEN; BEHAVIOR; ALUMINUM AB The role of hydrogen and crack tip strain rate on the stress corrosion cracking of austenitic stainless steels continues to be an unresolved issue for a number of conditions. Previous studies using Mode I and III loaded samples have been used to suggest that the preference of cracking in Mode I loaded samples supports a hydrogen induced cracking mechanism. However, the lack of cracking opening and environmental ingress to the crack tip in Mode III loading leaves some doubt about these conclusions. Stress corrosion cracking tests using a new test sample where the mode mixity between Mode I and III can be varied have been conducted and are reported for sensitized Type 304 SS tested in 0.21 M H3BO3 + 0.01 M (580 ppm) NaCl. Tests were conducted with samples with cracks at angles of 0, 30 and 45 degrees to the principal loading stress. The results from these tests clearly demonstrated the crack velocity does not decrease with increasing amounts of Mode III loading in contrast to expectations from a hydrogen induced cracking mechanism. The crack velocity showed a slight maximum for samples with crack angles of 30 degrees relative to 0 and 45 degrees. The reason for this maximum is not known but could be the result of increasing crack tip strain rates with increasing Mode III loading. Published by Elsevier Science S.A. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Jones, RH (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 25 TC 3 Z9 3 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD FEB 29 PY 2000 VL 279 IS 1-2 BP 42 EP 51 DI 10.1016/S0921-5093(99)00636-X PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 279WZ UT WOS:000085069200006 ER PT J AU Martin, LP Lindgren, EA Rosen, M Sidhu, H AF Martin, LP Lindgren, EA Rosen, M Sidhu, H TI Ultrasonic determination of elastic moduli in cement during hydrostatic loading to 1 GPa SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE cement; mortar; hydrostatic pressure; ultrasonic velocity; elastic moduli ID POROSITY AB An ultrasonic methodology has been developed for determination of the elastic constants of porous, cementitious materials as a function of applied hydrostatic pressures up to 1 GPa. The methodology can be performed upon bulk samples and in a fashion, which is more controlled than traditional impact (shock wave) testing. In-addition, data can be acquired during both the application; and release of the pressure. The data for mortar and cement paste samples, with porosity ranging from 13.7 to 24.1% by volume, indicate that during the initial application of pressure there is an irreversible, approximately linear, increase in the elastic moduli associated with the compaction of the pores. During subsequent cycling of the pressure, a slight 'hysteresis' was observed, with sound wave velocities and elastic moduli being slightly lower during the application of the pressure than during the release of the pressure. This effect was observed to be reproducible, and is consistent with a weak bonding between crack or pore faces forced into contact by the applied pressure. Use of the proposed ultrasonic methodology for quantification of the effects of pressure on the elastic moduli in cement-based materials will provide the foundation for accurate modeling of the behavior of cementitious materials during a broad range of high-strain inducing conditions such as ballistic impact (military) or geological instability (civilian). (C) 2000 Elsevier Science S.A. All Fights reserved. C1 Ind Qual Inc, Gaithersburg, MD 20877 USA. Johns Hopkins Univ, Dept Mat Sci & Engn, Baltimore, MD 21218 USA. USAF, Res Lab, Eglin AFB, FL 32542 USA. RP Martin, LP (reprint author), Univ Calif Lawrence Livermore Natl Lab, Mail Stop L-228,POB 808, Livermore, CA 94551 USA. NR 15 TC 10 Z9 10 U1 0 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD FEB 29 PY 2000 VL 279 IS 1-2 BP 87 EP 94 DI 10.1016/S0921-5093(99)00639-5 PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 279WZ UT WOS:000085069200011 ER PT J AU Brunori, M Vallone, B Cutruzzola, F Travaglini-Allocatelli, C Berendzen, J Chu, K Sweet, RM Schlichting, I AF Brunori, M Vallone, B Cutruzzola, F Travaglini-Allocatelli, C Berendzen, J Chu, K Sweet, RM Schlichting, I TI The role of cavities in protein dynamics: Crystal structure of a photolytic intermediate of a mutant myoglobin SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE cryo-crystallography; heme proteins; ligand binding; function ID SPERM WHALE MYOGLOBIN; LIGAND-BINDING; CARBONMONOXY-MYOGLOBIN; MOLECULAR-DYNAMICS; MONOXIDE; PHOTODISSOCIATION; RECOMBINATION; DIFFRACTION; SIMULATION; PICOSECOND AB We determined the structure of the photolytic intermediate of a sperm whale myoglobin (Mb) mutant called Mb-YQR [Leu(B10)-->Tyr; His(E7)-->Gln; Thr(E10)-->Arg] to 1.4-Angstrom resolution by ultra-low temperature (20 K) x-ray diffraction. Starting with the CO complex, illumination leads to photolysis of the Fe-CO bond, and migration of the photolyzed carbon monoxide (CO*) to a niche in the protein 8.1 Angstrom from the heme iron; this cavity corresponds to that hosting an atom of Xe when the crystal is equilibrated with xenon gas at 7 atmospheres [Tilton, R. F,, Jr., Kuntz, I. D. & Petsko, G. A, (1984) Biochemistry 23, 2849-2857]. The site occupied by CO* corresponds to that predicted by molecular dynamics simulations previously carried out to account for the NO geminate rebinding of Mb-YQR observed in laser photolysis experiments at room temperature. This secondary docking site differs from the primary docking site identified by previous crystallographic studies on the photolyzed intermediate of wild-type sperm whale Mb performed at cryogenic temperatures [Teng et al. (1994) Nat Struct. Biol, 1, 701-705] and room temperature [Srajer et al, (1996) Science 274, 1726-1729]. Our experiment shows that the pathway of a small molecule in its trajectory through a protein may be modified by site-directed mutagenesis, and that migration within the protein matrix to the active site involves a limited number of pre-existing cavities identified in the interior space of the protein. C1 Univ Rome La Sapienza, Dept Biochem Sci, Consiglio Nazl Ric, Ctr Mol Biol, I-00185 Rome, Italy. Univ Rome La Sapienza, Ist Pasteur, Fdn Cenci Bolognetti, I-00185 Rome, Italy. Univ Calif Los Alamos Natl Lab, Biophys Grp, Los Alamos, NM 87545 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. Max Planck Inst Mol Physiol, Dept Phys Biochem, D-44227 Dortmund, Germany. RP Brunori, M (reprint author), Univ Rome La Sapienza, Dept Biochem Sci, Consiglio Nazl Ric, Ctr Mol Biol, Piazzale Aldo Moro 5, I-00185 Rome, Italy. RI Cutruzzola, Francesca/G-4052-2011; Vallone, Beatrice/F-4174-2012; Schlichting, Ilme/I-1339-2013; OI Cutruzzola, Francesca/0000-0002-4621-2135; Brunori, Maurizio/0000-0002-7795-1635 NR 34 TC 132 Z9 135 U1 2 U2 8 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 FEB 29 PY 2000 VL 97 IS 5 BP 2058 EP 2063 DI 10.1073/pnas.040459697 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 289QJ UT WOS:000085633200020 PM 10681426 ER PT J AU Tsukamoto, T Yoo, J Hwang, SI Guzman, RC Hirokawa, Y Chou, YC Olatunde, S Huang, T Bera, TK Yang, J Nandi, S AF Tsukamoto, T Yoo, J Hwang, SI Guzman, RC Hirokawa, Y Chou, YC Olatunde, S Huang, T Bera, TK Yang, J Nandi, S TI Expression of MAT1/PEA-15 mRNA isoforms during physiological and neoplastic changes in the mouse mammary gland SO CANCER LETTERS LA English DT Article DE in vitro transformation; MAT1; PEA-15; 3 ' untranslated region; riboregulator ID PROTEIN-KINASE-C; CARCINOGEN-TREATED MICE; 3' UNTRANSLATED REGION; METHYL-N-NITROSOUREA; CANCER CELL-LINES; EPITHELIAL-CELLS; MESSENGER-RNA; HUMAN HOMOLOG; CDNA CLONING; SERUM-FREE AB MAT1 is a novel transforming gene which was cloned from a mouse mammary tumor induced by N-methyl-N-nitrosourea in vitro in the presence of lithium as a mitogen. Later, it was found to be identical to the 3' untranslated region (UTR) of the 2.5 kb isoform of PEA-15 (phosphoprotein enriched in astrocytes-15 kDa). We re-cloned MAT1/PEA-15 cDNAs and showed 2.5, 2.0 and 1.8 kb isoforms and confirmed MAT1 localization as reported. The 2.0 and 1.8 kb isoforms were produced by alternative splicing and alternative polyadenylation at the 3' UTR, respectively. To analyze the role of MAT1/PEA-15, we examined the expression of MAT1/PEA-15 mRNA in normal mammary tissues and in mammary tumors. The mammary gland during pregnancy, lactation and weaning showed weak but stable expression. Compared with normal mammary gland, mammary rumors showed stronger expression. Aberrant expression of MAT1/PEA-15 isoforms was found in mouse mammary epithelial cell lines, FSK7 and TM6, which lost the 2.5/2.0 and 2.5 kb isoforms, respectively. In contrast to other oncogenes like c-myc, MAT1/PEA-15 mRNA was extremely stable after actinomycin D and cycloheximide treatments suggesting that other protein expression is prerequisite for degradation of MAT1/PEA-15 mRNA. It evoked the possibility of the 3' UTR of MAT1/PEA-15 (designated as MAT1-T) as a riboregulator in mammary tumorigenesis and necessity for further analysis of human breast cancers as well as mouse mammary tumors. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved. C1 Univ Calif Berkeley, Canc Res Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Tsukamoto, T (reprint author), Aichi Canc Ctr, Res Inst, Pathol Lab, Chikusa Ku, 1-1 Kanokoden, Nagoya, Aichi 4648681, Japan. FU NCI NIH HHS [CA-05388, CA-63369] NR 45 TC 20 Z9 21 U1 0 U2 0 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0304-3835 J9 CANCER LETT JI Cancer Lett. PD FEB 28 PY 2000 VL 149 IS 1-2 BP 105 EP 113 DI 10.1016/S0304-3835(99)00350-X PG 9 WC Oncology SC Oncology GA 291BD UT WOS:000085712200014 PM 10737714 ER PT J AU Yunus, SM Fernandez-Baca, JA Asgar, MA Ahmed, FU AF Yunus, SM Fernandez-Baca, JA Asgar, MA Ahmed, FU TI Neutron diffraction study of magnetic ordering in the spinel oxide CoxMn1-xAl2xFe2-2xO4 SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE spinel oxides; ferrites; neutron diffraction; magnetic order; magnetic moment ID GLASS BEHAVIOR; FERRITE; ZNXCO1-XFECRO4; MOSSBAUER AB Four samples of the mixed spinel system CoxMn1-xAl2xFe2-2xO4 (x = 0.2, 0.4, 0.6, 0.8) were synthesized by ceramic sintering method. The magnetic ordering in the system has been investigated by neutron diffraction measurements in the temperature range 15-773 K. It appears that the system possesses a long-range ferrimagnetic ordering at x less than or equal to 0.6 along with some randomly canted spin components, while at x = 0.8 a semi-spin glass behavior is observed. The latter composition exhibits three transitions: at temperatures larger than 100 K, there is formation of magnetic spin clusters showing super-paramagnetic type behavior before the true paramagnetic region is reached at about 200 K; a ferrimagnetic long-range ordering is observed in the temperature range 100-50 K; and finally below 50 K there is freezing of the magnetic spin clusters. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Inst Nucl Sci & Technol, Atom Energy Estab, Dhaka 1000, Bangladesh. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Bangladesh Univ Engn & Technol, Dept Phys, Dhaka 1000, Bangladesh. RP Yunus, SM (reprint author), Inst Nucl Sci & Technol, Atom Energy Estab, POB 3787, Dhaka 1000, Bangladesh. RI Fernandez-Baca, Jaime/C-3984-2014 OI Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 29 TC 16 Z9 16 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD FEB 28 PY 2000 VL 298 IS 1-2 BP 9 EP 17 DI 10.1016/S0925-8388(99)00613-1 PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 277NL UT WOS:000084939600002 ER PT J AU Brunger, MJ Campbell, L Cartwright, DC Middleton, AG Mojarrabi, B Teubner, PJO AF Brunger, MJ Campbell, L Cartwright, DC Middleton, AG Mojarrabi, B Teubner, PJO TI Electron-impact excitation of Rydberg and valence electronic states of nitric oxide: I. Differential cross sections SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID QUANTUM-NUMBER DEPENDENCE; CORRELATION PARAMETERS; AURORAL CONDITIONS; INCIDENT ENERGIES; NO MOLECULE; SCATTERING; COLLISIONS; SYSTEMS; HELIUM; N2O AB Differential cross sections for 18 excited electronic states and 4 composite excited electronic states in nitric oxide (NO) have been determined for incident electron energies of 15, 20, 30, 40 and 50 eV. These differential cross sections were obtained for the scattered electron angle range 10 degrees-90 degrees by analysing electron energy-loss spectra in NO at a number of fixed scattering angles within that range. This study appears to be the first comprehensive investigation of electron-impact excitation of the electronic states of NO to be reported in the literature. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Flinders Univ S Australia, Dept Phys, Adelaide, SA 5001, Australia. RP Brunger, MJ (reprint author), UCL, Dept Phys & Astron, Gower St, London WC1E 6BT, England. NR 74 TC 29 Z9 29 U1 2 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 EI 1361-6455 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD FEB 28 PY 2000 VL 33 IS 4 BP 783 EP 808 DI 10.1088/0953-4075/33/4/314 PG 26 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 292UL UT WOS:000085813400020 ER PT J AU Brunger, MJ Campbell, L Cartwright, DC Middleton, AG Mojarrabi, B Teubner, PJO AF Brunger, MJ Campbell, L Cartwright, DC Middleton, AG Mojarrabi, B Teubner, PJO TI Electron-impact excitation of Rydberg and valence electronic states of nitric oxide: II. Integral cross sections SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID ELASTIC-SCATTERING; DIATOMIC-MOLECULES; NO; RESONANCES AB Integral cross sections (ICSs) for the excitation of 18 excited electronic states, and four composite excited electronic states, in nitric oxide (NO) have been determined for incident electron energies of 15, 20, 30, 40 and 50 eV. These ICSs were derived by extrapolating the respective measured differential cross sections (M J Brunger et al 2000 J. Phys. B: At. Mel. Opt. Phys. 33 783) to 0 degrees and 180 degrees and by performing the appropriate integration. Comparison of the present ICSs with the results of those determined in earlier optical emission measurements, and from theoretical calculations is made. At each incident energy considered the current ICSs are also summed along with the corresponding elastic and rovibrational excitation ICSs from B Mojarrabi et al (1995 J. Phys. B: At. Mel. Opt. Phys. 28 487) and the ionization cross sections from Rapp and Englander-Golden (1965 J. Chem. Phys. 43 1464), to derive an estimate of the grand total cross sections (GTSs) for e(-)+ NO scattering. The GTSs derived in this manner are compared with the results from independent linear transmission experiments and are found to be entirely consistent with them. The present excited electronic state ICS, and those for elastic and rovibrational excitation from Mojarrabi eb al, appear to represent the first set of self-consistent cross sections for electron impact scattering from NO. C1 Flinders Univ S Australia, Dept Phys, Adelaide, SA 5001, Australia. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Brunger, MJ (reprint author), UCL, Dept Phys & Astron, Gower St, London WC1E 6BT, England. NR 21 TC 25 Z9 25 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD FEB 28 PY 2000 VL 33 IS 4 BP 809 EP 819 DI 10.1088/0953-4075/33/4/315 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 292UL UT WOS:000085813400021 ER PT J AU Barnett, SM Aspect, A Milonni, PW AF Barnett, SM Aspect, A Milonni, PW TI On the quantum nature of the Casimir-Polder interaction SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Letter ID VAN-DER-WAALS; MIRROR; ATOMS; FORCE AB We compare the form of the Casimir-Polder interaction between a ground-state atom and a reflecting surface with the form obtained from a semiclassical calculation based on the method of images. The difference between these potentials is attributable to operator ordering and to the fundamentally different role prayed by the positive- and negative-frequency parts of the electric field in classical and quantum electrodynamics. Only with normal ordering does the images method lead to the fully quantum result. C1 Univ Strathclyde, Dept Phys & Appl Phys, Glasgow G4 0NG, Lanark, Scotland. Inst Opt, F-91403 Orsay, France. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Barnett, SM (reprint author), Univ Strathclyde, Dept Phys & Appl Phys, Glasgow G4 0NG, Lanark, Scotland. NR 21 TC 8 Z9 8 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD FEB 28 PY 2000 VL 33 IS 4 BP L143 EP L149 DI 10.1088/0953-4075/33/4/106 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 292UL UT WOS:000085813400006 ER PT J AU Reinhold, CO Arbo, DG Burgdorfer, J Gervais, G Lamour, E Vernhet, D Rozet, JP AF Reinhold, CO Arbo, DG Burgdorfer, J Gervais, G Lamour, E Vernhet, D Rozet, JP TI Enhanced population of high-l states due to the interplay between multiple scattering and dynamical screening in ion-solid collisions SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Letter ID RYDBERG STATES; ELECTRON-CAPTURE; ATOM COLLISIONS; EXCITED-STATES; EVOLUTION; HYDROGEN; ENERGIES AB We present a study of the sub-shell populations of 13.6 MeV/u Ar17+ ions after transmission through thin carbon foils. We show that the combined effect of the wake field induced by the ion in the solid and multiple collisions leads to a strongly enhanced population of high angular momentum states. These results explain new experimental data for absolute total line emission intensities. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Inst Astron & Fis Espacio, RA-1428 Buenos Aires, DF, Argentina. Vienna Tech Univ, Inst Theoret Phys, A-1040 Vienna, Austria. ISMRA, CNR, CEA, Ctr Interdisciplinaire Rech Ion Lasers,Lab Mixte, F-14070 Caen 05, France. Univ Paris 06, CNRS, Phys Solides Grp, UMR 75 88, F-75252 Paris 05, France. Univ Paris 07, F-75252 Paris 05, France. RP Reinhold, CO (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. OI Reinhold, Carlos/0000-0003-0100-4962 NR 29 TC 13 Z9 13 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD FEB 28 PY 2000 VL 33 IS 4 BP L111 EP L117 DI 10.1088/0953-4075/33/4/102 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 292UL UT WOS:000085813400002 ER PT J AU Bermejo, FJ Jimenez-Ruiz, M Criado, A Cuello, GJ Cabrillo, C Trouw, FR Fernandez-Perea, R Lowen, H Fischer, HE AF Bermejo, FJ Jimenez-Ruiz, M Criado, A Cuello, GJ Cabrillo, C Trouw, FR Fernandez-Perea, R Lowen, H Fischer, HE TI Rotational freezing in plastic crystals: a model system for investigating the dynamics of the glass transition SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 4th Liquid Matter Conference CY JUL 03-07, 1999 CL GRANADA, SPAIN SP European Phys Soc, Ayuntamiento Granada, Caja Gen Ahorros Granada, Camara Comerico Ind Navegac, Cervezas Alhambra, Comis Interminist Ciencia Technol, EDP Sci, Genesys, Iberia Lineas Aereas Espana, IOP Publishing Ltd, Junta Andalucia, Minist Educ Cultura, Optilas Iberica, OWIS GmbH, Repsol, Royal Soc Chem, Unicaja, Univ Granada ID THIN HARD-RODS; MOLECULAR-DYNAMICS; DISORDERED MATTER; ORDER AB The dynamics of the rotational freezing transition of the rotator phase (RP) crystal of ethanol into its orientational glass (OG) phase is monitored by measurements of molecular rotational components in the quasielastic neutron scattering spectrum. Such a transition is known to share several features in common with the canonical liquid --> glass transition (both taking place within the same temperature interval), and therefore some of the results from such a study should be of relevance for our understanding of the latter. We show that the basic features of the RP --> OG transition can be understood in terms of a hard-needle model by means of a mapping of the aspect ratio onto a temperature scale. C1 CSIC, E-28006 Madrid, Spain. Univ Sevilla, Dept Fis Mat Condensada, E-41080 Seville, Spain. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Dusseldorf, Inst Theoret Phys 2, D-40225 Dusseldorf, Germany. Inst Max Von Laue Paul Langevin, F-38042 Grenoble 9, France. RP Bermejo, FJ (reprint author), CSIC, Serrano 121-123, E-28006 Madrid, Spain. RI Cuello, Gabriel/C-5831-2009; Fernandez-Perea, Ricardo/E-9118-2016; Lowen, Hartmut/K-9999-2016; Fischer, Henry/D-5299-2012 OI Cuello, Gabriel/0000-0003-3844-0602; Fernandez-Perea, Ricardo/0000-0002-4011-2344; Lowen, Hartmut/0000-0001-5376-8062; Fischer, Henry/0000-0002-1204-0750 NR 18 TC 5 Z9 5 U1 1 U2 5 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 FEB 28 PY 2000 VL 12 IS 8A BP A391 EP A397 DI 10.1088/0953-8984/12/8A/353 PG 7 WC Physics, Condensed Matter SC Physics GA 295WN UT WOS:000085991000054 ER PT J AU DiMasi, E Tostmann, H Shpyrko, OG Deutsch, M Pershan, PS Ocko, BM AF DiMasi, E Tostmann, H Shpyrko, OG Deutsch, M Pershan, PS Ocko, BM TI Surface-induced order in liquid metals and binary alloys SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 4th Liquid Matter Conference CY JUL 03-07, 1999 CL GRANADA, SPAIN SP European Phys Soc, Ayuntamiento Granada, Caja Gen Ahorros Granada, Camara Comerico Ind Navegac, Cervezas Alhambra, Comis Interminist Ciencia Technol, EDP Sci, Genesys, Iberia Lineas Aereas Espana, IOP Publishing Ltd, Junta Andalucia, Minist Educ Cultura, Optilas Iberica, OWIS GmbH, Repsol, Royal Soc Chem, Unicaja, Univ Granada ID X-RAY REFLECTIVITY; VAPOR INTERFACE; GALLIUM AB Measurements of the surface x-ray scattering from several pure Liquid metals (Hg, Ga, and In) and from three alloys (Ga-Bi, Bi-In, and K-Na) with different heteroatomic chemical interactions in the bulk phase are reviewed. Surface-induced layering is found for each elemental liquid metal. The surface structure of the K-Na alloy resembles that of an elemental liquid metal. Bi-In displays pair formation at the surface. Surface segregation and a wetting film are found for Ga-Bi. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel. RP DiMasi, E (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Shpyrko, Oleg/J-3970-2012 NR 17 TC 13 Z9 13 U1 1 U2 7 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 FEB 28 PY 2000 VL 12 IS 8A BP A209 EP A214 PG 6 WC Physics, Condensed Matter SC Physics GA 295WN UT WOS:000085991000026 ER PT J AU Gang, O Ocko, BM Wu, XZ Sirota, EB Deutsch, M AF Gang, O Ocko, BM Wu, XZ Sirota, EB Deutsch, M TI Structural control of the surface-frozen layer in alcohol melts SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 4th Liquid Matter Conference CY JUL 03-07, 1999 CL GRANADA, SPAIN SP European Phys Soc, Ayuntamiento Granada, Caja Gen Ahorros Granada, Camara Comerico Ind Navegac, Cervezas Alhambra, Comis Interminist Ciencia Technol, EDP Sci, Genesys, Iberia Lineas Aereas Espana, IOP Publishing Ltd, Junta Andalucia, Minist Educ Cultura, Optilas Iberica, OWIS GmbH, Repsol, Royal Soc Chem, Unicaja, Univ Granada ID LIQUID NORMAL-ALKANES AB Surface crystallization in alcohol melts results in the formation of a crystalline bilayer at the melt's surface above the freezing temperature. We demonstrate here that the structure of this surface-frozen bilayer can be varied using specific bulk additives, wafer and diols. Surface-specific x-ray methods show that water swells the bilayer by intercalating into its centre at a molecular water:alcohol ratio of similar to 1:2. It also induces surface freezing at chain lengths not showing the effect when dry. Diols are found to induce a reversible monolayer-bilayer surface phase transition. The surface phase diagram is determined and found to depend on the diol's chain length and concentration, in addition to temperature. The physics underlying the phase behaviour is discussed. C1 Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. Exxon Res & Engn Co, Annandale, NJ 08801 USA. RP Deutsch, M (reprint author), Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel. RI Sirota, Eric/A-7633-2009 NR 15 TC 4 Z9 4 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD FEB 28 PY 2000 VL 12 IS 8A BP A357 EP A362 DI 10.1088/0953-8984/12/8A/348 PG 6 WC Physics, Condensed Matter SC Physics GA 295WN UT WOS:000085991000049 ER PT J AU He, XM Walter, KC Nastasi, M AF He, XM Walter, KC Nastasi, M TI Plasma-immersion ion-processed boron-doped diamond-like carbon films SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Letter ID AMORPHOUS HYDROGENATED CARBON AB Boron-doped diamond-like carbon (DLC) was prepared using an inductive radio-frequency Ar + C2H2 + B2H6 plasma-immersion ion-processing (PIIP) technique. The novel results show that B incorporation reduces the stress and that low-energy Ar-ion impingement suppresses the increase of the amount of hydrogen in the B-doped DLC film. An optimal combination of higher hardness, 24.6-28 GPa, and reduced stress was reached in DLC film doped with 4 to 10 at.% B. An increase in the sp(3) carbon and sp(3) CH bonding in the DLC films was found with B doping and was correlated with the enhancement of the properties. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP He, XM (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. NR 20 TC 14 Z9 14 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 FEB 28 PY 2000 VL 12 IS 8 BP L183 EP L189 DI 10.1088/0953-8984/12/8/105 PG 7 WC Physics, Condensed Matter SC Physics GA 294RG UT WOS:000085923700005 ER PT J AU Goldman, T Stephenson, GJ McKellar, BHJ AF Goldman, T Stephenson, GJ McKellar, BHJ TI Implications of quark-lepton symmetry for neutrino masses and oscillations SO MODERN PHYSICS LETTERS A LA English DT Article ID (NU)OVER-BAR(MU)->(NU)OVER-BAR(E) OSCILLATIONS; LSND EXPERIMENT; VIOLATION; PHYSICS; DECAY; DIRAC AB We identify a plausible scenario based on quark-lepton symmetry which correlates long baseline oscillations with maximal mixing to sterile neutrinos. The implication for the Sudbury Neutrino Observatory (SNO) is that the neutral current signal will be found to suffer the same suppression from the standard solar model prediction as obtains for the charged current signal. Flavor mixing among active neutrinos is expected to occur on shorter baselines with smaller mixing amplitudes. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. Univ Melbourne, Sch Phys, Parkville, Vic 3052, Australia. RP Goldman, T (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS B283, Los Alamos, NM 87545 USA. NR 36 TC 7 Z9 7 U1 0 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-7323 J9 MOD PHYS LETT A JI Mod. Phys. Lett. A PD FEB 28 PY 2000 VL 15 IS 6 BP 439 EP 443 DI 10.1142/S0217732300000426 PG 5 WC Physics, Nuclear; Physics, Particles & Fields; Physics, Mathematical SC Physics GA 303LF UT WOS:000086422800006 ER PT J AU Jun, SY Akchurin, N Andreev, VA Atamantchouk, AG Aykac, M Balatz, MY Bondar, NF Bravar, A Cooper, PS Dauwe, LJ Davidenko, GV Dersch, U Dolgolenko, AG Dreossi, D Dzyubenko, GB Edelstein, R Emediato, L Endler, AMF Engelfried, J Eschrich, I Escobar, CO Evdokimov, AV Filimonov, IS Garcia, FG Gaspero, M Gerzon, S Giller, I Golovtsov, VL Goncharenko, YM Gottschalk, E Gouffon, P Grachov, OA Gulmez, E Iori, M Kamenski, AD Kangling, H Kaya, M Kilmer, J Kim, VT Kochenda, LM Konigsmann, K Konorov, I Kozhevnikov, AA Krivshich, AG Kruger, H Kubantsev, MA Kubarovsky, VP Kulyavtsev, AI Kuropatkin, NP Kurshetsov, VF Kushnirenko, A Kwan, S Lach, J Lamberto, A Landsberg, LG Larin, I Leikin, EM Luksys, M Lungov, T Magarrel, D Maleev, VP Mao, D Masciocchi, S Mathew, P Mattson, M Matveev, V McCliment, E McKenna, SL Moinester, MA Molchanov, VV Morelos, A Mukhin, VA Nelson, KD Nemitkin, AV Neoustroev, PV Newsom, C Nilov, AP Nurushev, SB Ocherashvili, A Oleynik, G Onel, Y Ozel, E Ozkorucuklu, S Patrichev, S Penzo, A Petrenko, SI Pogodin, P Povh, B Procario, M Prutskoi, VA Ramberg, E Rappazzo, GF Razmyslovich, BV Rud, VI Russ, J Schiavon, P Semyatchkin, VK Simon, J Sitnikov, AI Skow, D Smith, VJ Srivastava, M Steiner, V Stepanov, V Stutte, L Svoiski, M Terentyev, NK Thomas, GP Uvarov, LN Vasiliev, AN Vavilov, DV Verebryusov, VS Victorov, VA Vishnyakov, VE Vorobyov, AA Vorwalter, K Wenheng, Z You, J Yunshan, L Zhenlin, M Zhigang, L Funchal, RZ AF Jun, SY Akchurin, N Andreev, VA Atamantchouk, AG Aykac, M Balatz, MY Bondar, NF Bravar, A Cooper, PS Dauwe, LJ Davidenko, GV Dersch, U Dolgolenko, AG Dreossi, D Dzyubenko, GB Edelstein, R Emediato, L Endler, AMF Engelfried, J Eschrich, I Escobar, CO Evdokimov, AV Filimonov, IS Garcia, FG Gaspero, M Gerzon, S Giller, I Golovtsov, VL Goncharenko, YM Gottschalk, E Gouffon, P Grachov, OA Gulmez, E Iori, M Kamenski, AD Kangling, H Kaya, M Kilmer, J Kim, VT Kochenda, LM Konigsmann, K Konorov, I Kozhevnikov, AA Krivshich, AG Kruger, H Kubantsev, MA Kubarovsky, VP Kulyavtsev, AI Kuropatkin, NP Kurshetsov, VF Kushnirenko, A Kwan, S Lach, J Lamberto, A Landsberg, LG Larin, I Leikin, EM Luksys, M Lungov, T Magarrel, D Maleev, VP Mao, D Masciocchi, S Mathew, P Mattson, M Matveev, V McCliment, E McKenna, SL Moinester, MA Molchanov, VV Morelos, A Mukhin, VA Nelson, KD Nemitkin, AV Neoustroev, PV Newsom, C Nilov, AP Nurushev, SB Ocherashvili, A Oleynik, G Onel, Y Ozel, E Ozkorucuklu, S Patrichev, S Penzo, A Petrenko, SI Pogodin, P Povh, B Procario, M Prutskoi, VA Ramberg, E Rappazzo, GF Razmyslovich, BV Rud, VI Russ, J Schiavon, P Semyatchkin, VK Simon, J Sitnikov, AI Skow, D Smith, VJ Srivastava, M Steiner, V Stepanov, V Stutte, L Svoiski, M Terentyev, NK Thomas, GP Uvarov, LN Vasiliev, AN Vavilov, DV Verebryusov, VS Victorov, VA Vishnyakov, VE Vorobyov, AA Vorwalter, K Wenheng, Z You, J Yunshan, L Zhenlin, M Zhigang, L Funchal, RZ CA SELEX Collaboration TI Observation of the Cabibbo-suppressed decay Xi(+)(c) -> pK(-)pi(+) SO PHYSICAL REVIEW LETTERS LA English DT Article ID BARYON DECAYS AB We report the first observation of the Cabibbo-suppressed charm baryon decay Xi(c)(+) --> pK(-)pi(+) We observe 150 +/- 22 +/- 5 events for the signal. The data were accumulated using the SELEX spectrometer during the 1996-1997 fixed target run at Fermilab, chiefly from a 600 GeV/c Sigma(-) beam. The branching fractions of the decay relative to the Cabibbo-favored Xi(c)(+) --> Sigma(+)K(-)pi(+) and Xi(c)(+) --> Xi(-)pi(+)pi(+) are measured to be B(Xi(c)(+) --> pK(-)pi(+))/B(Xi(c)(+) --> Sigma(+)K(-)pi(+)) = 0.22 +/- 0.06 +/- 0.03 and B(Xi(c)(+) --> pK(-)pi(+))/B(Xi(c)(+) --> Xi(-)pi(+)pi(+)) = 0.20 +/- 0.04 +/- 0.02, respectively. C1 Ball State Univ, Muncie, IN 47306 USA. Bogazici Univ, TR-80815 Bebek, Turkey. Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Inst High Energy Phys, Protvino, Russia. Inst High Energy Phys, Beijing 100039, Peoples R China. Inst Theoret & Expt Phys, Moscow 117259, Russia. Max Planck Inst Kernphys, D-69117 Heidelberg, Germany. Moscow State Univ, Moscow, Russia. Petersburg Nucl Phys Inst, St Petersburg, Russia. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Univ Autonoma San Luis Potosi, San Luis Potosi, Mexico. Univ Fed Paraiba, BR-58059900 Joao Pessoa, Paraiba, Brazil. Univ Bristol, Bristol BS8 1TL, Avon, England. Univ Iowa, Iowa City, IA 52242 USA. Univ Michigan, Flint, MI 48502 USA. Univ Rome La Sapienza, Rome, Italy. Ist Nazl Fis Nucl, Rome, Italy. Univ Sao Paulo, Sao Paulo, Brazil. Univ Trieste, Trieste, Italy. Ist Nazl Fis Nucl, Trieste, Italy. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RP Jun, SY (reprint author), Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RI Zukanovich Funchal, Renata/C-5829-2013; Russ, James/P-3092-2014; Gulmez, Erhan/P-9518-2015; Gouffon, Philippe/I-4549-2012; Maleev, Victor/R-4140-2016 OI Zukanovich Funchal, Renata/0000-0001-6749-0022; Russ, James/0000-0001-9856-9155; Gulmez, Erhan/0000-0002-6353-518X; Gouffon, Philippe/0000-0001-7511-4115; NR 8 TC 12 Z9 12 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD FEB 28 PY 2000 VL 84 IS 9 BP 1857 EP 1861 DI 10.1103/PhysRevLett.84.1857 PG 5 WC Physics, Multidisciplinary SC Physics GA 288WX UT WOS:000085588400003 PM 21923211 ER PT J AU McKee, G Burrell, K Fonck, R Jackson, G Murakami, M Staebler, G Thomas, D West, P AF McKee, G Burrell, K Fonck, R Jackson, G Murakami, M Staebler, G Thomas, D West, P TI Impurity-induced suppression of core turbulence and transport in the DIII-D tokamak SO PHYSICAL REVIEW LETTERS LA English DT Article ID MAGNETIC CONFINEMENT DEVICES; FUSION TEST REACTOR; FINITE ASPECT RATIO; I MODE-STABILITY; DENSITY; PLASMA; SHEAR; TFTR; FLUCTUATIONS; DISCHARGES AB Turbulence is significantly reduced in a tokamak plasma as a result of neon seeding of an L-mode discharge. Correspondingly, confinement is improved and cross-field ion thermal transport reduced. Fully saturated turbulence in the range 0.1 less than or equal to k(perpendicular to)rho(s) less than or equal to 0.6 is measured at rho = 0.7 and exhibits a factor of 5 reduction in total power after neon injection, with almost complete suppression for k(perpendicular to)rho(s) > 0.35. These observations are consistent with a reduction in the calculated linear growth rate fur k(perpendicular to)rho(s) > 0.5 and an increase in the measured E x B flow shearing rate. C1 Univ Wisconsin, Madison, WI 53706 USA. Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP McKee, G (reprint author), Univ Wisconsin, Madison, WI 53706 USA. NR 28 TC 35 Z9 35 U1 0 U2 8 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD FEB 28 PY 2000 VL 84 IS 9 BP 1922 EP 1925 DI 10.1103/PhysRevLett.84.1922 PG 4 WC Physics, Multidisciplinary SC Physics GA 288WX UT WOS:000085588400019 ER PT J AU Schultz, PA AF Schultz, PA TI Charged local defects in extended systems SO PHYSICAL REVIEW LETTERS LA English DT Article ID TOTAL-ENERGY CALCULATIONS; PSEUDOPOTENTIALS; ADSORBATE AB The conventional approach to treat charged defects in extended systems in first principles calculations is via the supercell approximation using a neutralizing jellium charge. I explicitly show that errors in the resulting electrostatic potential surface are comparable to a band gap energy in semiconductors, for cell sizes typically used in simulations. I present a method for eliminating divergence of the Coulomb potential in charged supercell calculations thar correctly treats the electrostatic potential in the local vicinity of a charged defect. via a mixed boundary condition approach. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 98 Z9 98 U1 1 U2 15 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 FEB 28 PY 2000 VL 84 IS 9 BP 1942 EP 1945 DI 10.1103/PhysRevLett.84.1942 PG 4 WC Physics, Multidisciplinary SC Physics GA 288WX UT WOS:000085588400024 ER PT J AU Shahbazyan, TV Primozich, N Perakis, IE Chemla, DS AF Shahbazyan, TV Primozich, N Perakis, IE Chemla, DS TI Femtosecond coherent dynamics of the Fermi-edge singularity and exciton hybrid SO PHYSICAL REVIEW LETTERS LA English DT Article ID DOPED QUANTUM-WELLS; OPTICAL-SPECTRA; SEMICONDUCTORS; MAGNETOEXCITONS; REGIME; SYSTEM AB We study theoretically the coherent nonlinear optical response of doped quantum wells with several subbands. When the Fermi energy approaches the exciton level of an upper subband, the absorption spectrum acquires a characteristic double-peak shape originating from the interference between the Fermi-edge singularity and the exciton resonance. We demonstrate that, for off-resonant Dump excitation, the pump-probe spectrum undergoes a striking transformation, with a time-dependent exchange of oscillator strength between the Fermi-edge singularity and exciton peaks. This effect originates from the many-body electron-hole correlations which determine the dynamical response of the Fermi sea. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Shahbazyan, TV (reprint author), Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RI Perakis, Ilias/G-9186-2011 NR 26 TC 21 Z9 21 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 FEB 28 PY 2000 VL 84 IS 9 BP 2006 EP 2009 DI 10.1103/PhysRevLett.84.2006 PG 4 WC Physics, Multidisciplinary SC Physics GA 288WX UT WOS:000085588400040 PM 11017682 ER PT J AU Ioffe, A Arif, M Jacobson, DL Mezei, F AF Ioffe, A Arif, M Jacobson, DL Mezei, F TI Comment on "Precision neutron interferometric search for evidence of nuclear quantum entanglement in liquid H2O-D2O mixtures" Ioffe et al. reply SO PHYSICAL REVIEW LETTERS LA English DT Article C1 Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, Berlin Neutron Scattering Ctr, D-14109 Berlin, Germany. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ioffe, A (reprint author), Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. NR 3 TC 3 Z9 3 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 FEB 28 PY 2000 VL 84 IS 9 BP 2037 EP 2037 DI 10.1103/PhysRevLett.84.2037 PG 1 WC Physics, Multidisciplinary SC Physics GA 288WX UT WOS:000085588400050 PM 21923218 ER PT J AU Cook, BA Harringa, JL Lewis, TL Russell, AM AF Cook, BA Harringa, JL Lewis, TL Russell, AM TI A new class of ultra-hard materials based on AlMgB14 SO SCRIPTA MATERIALIA LA English DT Article DE hard materials; mechanical alloying; complex borides ID SOLIDS C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Cook, BA (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 12 TC 106 Z9 114 U1 2 U2 22 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD FEB 28 PY 2000 VL 42 IS 6 BP 597 EP 602 DI 10.1016/S1359-6462(99)00400-5 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 295AN UT WOS:000085943800013 ER PT J AU Froidevaux, L Waters, JW Read, WG Connell, PS Kinnison, DE Russell, JM AF Froidevaux, L Waters, JW Read, WG Connell, PS Kinnison, DE Russell, JM TI Variations in the free chlorine content of the stratosphere (1991-1997): Anthropogenic, volcanic, and methane influences SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID IN-SITU MEASUREMENTS; LONG-TERM TREND; SULFATE AEROSOLS; OZONE DEPLETION; MOUNT-PINATUBO; MT-PINATUBO; CLO; NO2; ERUPTION; CHLOROFLUOROCARBONS AB Remote sensing of chlorine monoxide (ClO) by the Microwave Limb Sounder experiment aboard the Upper Atmosphere Research Satellite (UARS) has provided global measurements of variations in stratospheric free chlorine for 1991-1997. Linear trends were obtained from a multiple regression analysis of this data set at low latitudes and midlatitudes. ClO increases in the upper stratosphere (2 hPa) are significantly larger than expected from trends in chlorine source gases alone. Much of the upper stratospheric ClO variability can be explained by changes in CH4, as measured by the UARS Halogen Occultation Experiment. Decreasing ClO in the lower stratosphere is consistent with a relaxation from a chemically perturbed state attributed to the 1991 Mt. Pinatubo eruption. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Mail Stop 183-701, Pasadena, CA 91109 USA. EM lucien@mls.jpl.nasa.gov; connell2@llnl.gov; dkin@acd.ucar.edu NR 42 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 EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD FEB 27 PY 2000 VL 105 IS D4 BP 4471 EP 4481 DI 10.1029/1999JD901039 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 287NU UT WOS:000085512800008 ER PT J AU Dong, XQ Minnis, P Ackerman, TP Clothiaux, EE Mace, GG Long, CN Liljegren, JC AF Dong, XQ Minnis, P Ackerman, TP Clothiaux, EE Mace, GG Long, CN Liljegren, JC TI A 25-month database of stratus cloud properties generated from ground-based measurements at the Atmospheric Radiation Measurement Southern Great Plains Site SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CLIMATE MODELS; WATER CLOUDS; PARAMETERIZATION; EARTH AB A 25-month database of the macrophysical, microphysical, and radiative properties of isolated and overcast low-level stratus clouds has been generated using a newly developed parameterization and surface measurements from the Atmospheric Radiation Measurement central facility in Oklahoma. The database (5-min resolution) includes two parts: measurements and retrievals. The former consist of cloud base and top heights, layer-mean temperature, cloud liquid water path, and solar transmission ratio measured by a ground-based lidar/ceilometer and radar pair, radiosondes, a microwave radiometer, and a standard Eppley precision spectral pyranometer, respectively. The retrievals include the cloud-droplet effective radius and number concentration and broadband shortwave optical depth and cloud and top-of-atmosphere albedos. Stratus without any overlying mid or high-level clouds occurred most frequently during winter and least often during summer. Mean cloud-layer altitudes and geometric thicknesses were higher and greater, respectively, in summer than in winter. Both quantities are positively correlated with the cloud-layer mean temperature. Mean cloud-droplet effective radii range from 8.1 mu m in winter to 9.7 mu m during summer, while cloud-droplet number concentrations during winter are nearly twice those in summer. Since cloud liquid water paths are almost the same in both seasons, cloud optical depth is higher during the winter, leading to greater cloud albedos and lower cloud transmittances. C1 Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Pacific NW Lab, Richland, WA 99352 USA. Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. US DOE, Ames Lab, Ctr Nondestruct Evaluat, Ames, IA 50011 USA. RP Univ Utah, Dept Meteorol, 819 Wm C Browning Bldg, Salt Lake City, UT 84112 USA. EM xdong@met.utah.edu; p.minnis@larc.nasa.gov; Thomas.Ackerman@pnl.gov; cloth@essc.psu.edu; mace@met.utah.edu; long@essc.psu.edu; jim@ultral.cnde.iastate.edu RI Minnis, Patrick/G-1902-2010; OI Minnis, Patrick/0000-0002-4733-6148; Dong, Xiquan/0000-0002-3359-6117 NR 24 TC 43 Z9 44 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD FEB 27 PY 2000 VL 105 IS D4 BP 4529 EP 4537 DI 10.1029/1999JD901159 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 287NU UT WOS:000085512800013 ER PT J AU Schuster, PF White, DE Naftz, DL Cecil, LD AF Schuster, PF White, DE Naftz, DL Cecil, LD TI Chronological refinement of an ice core record at Upper Fremont Glacier in south central North America SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ELECTRICAL-CONDUCTIVITY; GREENLAND; VOLCANISM; CLIMATE; GISP2; INSTABILITY; ISOTOPES; SIGNAL; SUMMIT; SNOW AB The potential to use ice cores from alpine glaciers in the midlatitudes to reconstruct paleoclimatic records has not been widely recognized. Although excellent paleoclimatic records exist for the polar regions, paleoclimatic ice core records are not common from midlatitude locations. An ice core removed from the Upper Fremont Glacier in Wyoming provides evidence for abrupt climate change during the mid-1800s. Volcanic events (Krakatau and Tambora) identified from electrical conductivity measurements (ECM) and isotopic and chemical data from the Upper Fremont Glacier were reexamined to confirm and refine previous chronological estimates of the ice core. At a depth of 152 m the refined age-depth profile shows good agreement (1736 +/- 10 A.D.) with the C-14 age date (1729 +/- 95 A.D.). The delta(18)O profile of the Upper Fremont Glacier (UFG) ice core indicates a change in climate known as the Little Ice Age (LIA). However, the sampling interval for delta(18)O is sufficiently large (20 cm) such that it is difficult to pinpoint the LIA termination on the basis of delta(18)O data alone. Other research has shown that changes in the delta(18)O variance are generally coincident with changes in ECM variance. The ECM data set contains over 125,000 data points at a resolution of 1 data point per millimeter of ice core. A 999-point running average of the ECM data set and results from f tests indicates that the variance of the ECM data decreases significantly at about 108 m. At this depth, the age-depth profile predicts an age of 1845 A.D. Results indicate the termination of the LIA was abrupt with a major climatic shift to warmer temperatures around 1845 A.D. and continuing to present day. Prediction limits (error bars) calculated for the profile ages are +/-10 years (90% confidence level). Thus a conservative estimate for the time taken to complete the LIA climatic shift to present-day climate is about 10 years, suggesting the LIA termination in alpine regions of central North America may have occurred on a relatively short (decadal) timescale. C1 US Geol Survey, Div Water Resources, Boulder, CO 80303 USA. Golden Software, Golden, CO 80401 USA. US Geol Survey, Div Water Resources, Salt Lake City, UT 84104 USA. US Geol Survey, Div Water Resources, Idaho Falls, ID 83402 USA. RP US Geol Survey, Div Water Resources, 3215 Marine St, Boulder, CO 80303 USA. EM pschuste@usgs.gov; dave@goldensoftware.com; dlnaftz@usgs.gov; ldcecil@usgs.gov NR 28 TC 22 Z9 23 U1 2 U2 9 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD FEB 27 PY 2000 VL 105 IS D4 BP 4657 EP 4666 DI 10.1029/1999JD901095 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 287NU UT WOS:000085512800022 ER PT J AU Kumar, KS Pang, L Liu, CT Horton, J Kenik, EA AF Kumar, KS Pang, L Liu, CT Horton, J Kenik, EA TI Structural stability of the Laves phase Cr2Ta in a two-phase Cr-Cr2Ta alloy SO ACTA MATERIALIA LA English DT Article DE intermetallic compounds; Laves phase; phase transformation; electron diffraction; energy dispersive X-ray analysis (EDS) ID MECHANICAL-PROPERTIES; MICROSTRUCTURE AB Detailed microstructural analysis of a two-phase alloy of composition Cr-9.8 at.% Ta and lying in the Cr-Cr2Ta region of the Cr-Ta binary system confirmed that the existing phase diagram is inaccurate; in the cast and annealed condition (1273 K/24 h), blocky primary Cr2Ta precipitates were observed although the phase diagram indicates the eutectic composition to be similar to 13 at.% Ta. The eutectic structure is composed of Cr solid solution and the Laves phase Cr2Ta; the morphology is primarily lamellar although the rod morphology was occasionally observed. The Laves phase eutectic microconstituent exhibits the C14 (2H) hexagonal structure with a low stacking fault (basal faults) density and an average composition corresponding to 28.5 at.% Ta. After a prolonged high-temperature anneal (1573 K/168 h), the morphology breaks down to form discrete particles of Cr2Ta; the C14, C36 and C15 structures were all recognized in this annealed condition, often more than one form being present in a single precipitate. The C15 structure was not twinned but contained some stacking faults on the {111} planes. Composition measurements confirmed that these structural transformations were accompanied by composition changes, the precipitates becoming more Ta-rich as they transitioned from the C14 via the C36 to the C15 phase. These observations are coupled with the results from earlier studies to present a discussion on factors that influence the stability and C14/C36/C15 transformation kinetics. (C) 2000 Acta Metallurgica mr. Published by Elsevier Science Ltd. All rights reserved. C1 Brown Univ, Div Engn, Providence, RI 02912 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Kumar, KS (reprint author), Brown Univ, Div Engn, Providence, RI 02912 USA. OI Liu, Chain Tsuan/0000-0001-7888-9725 NR 23 TC 29 Z9 31 U1 4 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 EI 1873-2453 J9 ACTA MATER JI Acta Mater. PD FEB 25 PY 2000 VL 48 IS 4 BP 911 EP 923 DI 10.1016/S1359-6454(99)00377-8 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 289DM UT WOS:000085605300010 ER PT J AU Misra, A Sharif, AA Petrovic, JJ Mitchell, TE AF Misra, A Sharif, AA Petrovic, JJ Mitchell, TE TI Rapid solution hardening at elevated temperatures by substitutional Re alloying in MoSi2 SO ACTA MATERIALIA LA English DT Article DE intermetallics; high temperature; dislocations; transmission electron microscopy (TEM); MoSi2 ID SINGLE-CRYSTALS; MECHANICAL-PROPERTIES; MOSI2-BASED ALLOYS; TRANSITION; COMPOSITES; BEHAVIOR; CREEP AB The mechanical properties of solidification processed polycrystalline MoSi2 and ternary (Mo, Re)Si-2 alloys were evaluated by compression testing at elevated temperatures. Rhenium is found to be a potent solid solution hardening addition to C11(b) MoSi2 at temperatures up to 1600 degrees C (highest temperature used in the study). Dislocation microstructures, characterized by electron microscopy, are consistent with the significant hardening exhibited by Re containing alloys. The high hardening rate cannot be explained by the classical substitutional solid solution hardening theories for metals based on atomic size misfit and elastic moduli mismatch. Since rhenium "disilicide" is semiconducting and has a Si-deficient stoichiometry of ReSi1.75, the addition of Re to MoSi2 may lead to the formation of constitutional Si vacancies which may pair with Re substitutionals to form point defect complexes. A model that describes the elliptical strain field (tetragonal distortion) around these point defects is used to interpret the rapid hardening by Re in MoSi2. Small additions of Re may provide the necessary high temperature strength in MoSi2-based structural intermetallic alloys for very high temperature applications (similar to 1200-1600 degrees C). (C) 2000 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Misra, A (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS K765, Los Alamos, NM 87545 USA. RI Misra, Amit/H-1087-2012 NR 36 TC 21 Z9 22 U1 1 U2 3 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 FEB 25 PY 2000 VL 48 IS 4 BP 925 EP 932 DI 10.1016/S1359-6454(99)00380-8 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 289DM UT WOS:000085605300011 ER PT J AU Rapp, R Schafer, T Shuryak, EV Velkovsky, M AF Rapp, R Schafer, T Shuryak, EV Velkovsky, M TI High-density QCD and instantons SO ANNALS OF PHYSICS LA English DT Article ID CHIRAL PHASE-TRANSITION; FINITE-TEMPERATURE; BARYON DENSITY; QUARK MATTER; LIQUID; VACUUM; SUPERCONDUCTIVITY; POINT; ZERO AB Instantons generate strong nonperturbative interactions between quarks. In vacuum, these interactions lead to chiral symmetry breaking and generate constituent quark masses on the order of 300 400 MeV. The observation that the same forces also provide attraction in the scalar diquark channel leads to the prediction that cold quark matter is a color superconductor, with gaps as large as similar to 100 MeV. We provide a systematic treatment of color superconductivity in the instanton model. We show that the structure of the superconductor depends on the number of flavors. In the case of two flavors, we verify the standard scenario, and provide an improved calculation of the mass gap. For three flavors, we show that the ground state is color-flavor locked and calculate the chiral condensate in the high-density phase. We show that as a function of the strange quark mass, there is a sharp transition between the two phases. Finally, we go beyond the mean-field approximation and investigate the role of instanton/anti-instanton molecules, which-in addition to superconducting gap formation-provide a competitive mechanism for chiral restoration at finite density. (C) 2000 Academic Press. C1 SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Inst Adv Study, Sch Nat Sci, Princeton, NJ 08540 USA. Brookhaven Natl Lab, Nucl Theory Grp, Upton, NY 11973 USA. RP SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. NR 66 TC 192 Z9 193 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0003-4916 EI 1096-035X J9 ANN PHYS-NEW YORK JI Ann. Phys. PD FEB 25 PY 2000 VL 280 IS 1 BP 35 EP 99 DI 10.1006/aphy.1999.5991 PG 65 WC Physics, Multidisciplinary SC Physics GA 292DC UT WOS:000085778000002 ER PT J AU Lu, YP Dixon, AG Moser, WR Ma, YH Balachandran, U AF Lu, YP Dixon, AG Moser, WR Ma, YH Balachandran, U TI Oxidative coupling of methane using oxygen-permeable dense membrane reactors SO CATALYSIS TODAY LA English DT Article; Proceedings Paper CT 3RD International Conference on Catalysis in Membrane Reactors (ICCMR 98) CY SEP 08-10, 1998 CL COPENHAGEN, DENMARK SP Brite Euram Programme, Haldor Topsoe A/S, Danish Soc Chem Engineers, Danish Catalyt Soc DE methane; oxidation; membrane ID PEROVSKITE; OXIDE; SYNGAS AB Oxidative coupling of methane was studied with La/MgO catalyst and a distributed oxygen feed through mixed-conducting dense membrane tubes in a shell-and-tube reactor configuration. A SrFeCo(0.5)O(3) membrane was tested, and, a blank run confirmed that it acted as a total oxidation catalyst, with no C(2) products. Attempts to coat the inside of the membrane tube with a non-combustion material BaCe(0.6)Sm(0.4)O(3) were only partially successful, giving 7% yield to C(2) products. The oxygen flux through the coated tube was reduced to 30% of its original value. A membrane tube was fabricated from a non-combustion oxygen-permeating material, BaCe(0.8)Gd(0.2)O(3), and it was confirmed that this was not a total oxidation catalyst. Yields to C(2) products of up to 16.5% were obtained, higher than those in comparable fixed bed studies. The C(2) yield obtained is the highest reported in the literature for oxidative coupling of methane in dense membrane reactors. The flux of oxygen through both dense membranes increased under reaction conditions, by a factor of four, over the non-reaction flux measured in permeation experiments. Changes in surface morphology were observed for the side of the membrane in contact with the reducing atmosphere. Similar phenomena have been observed in previous studies. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Worcester Polytech Inst, Dept Chem Engn, Worcester, MA 01609 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Dixon, AG (reprint author), Worcester Polytech Inst, Dept Chem Engn, Worcester, MA 01609 USA. EM agdixon@wpi.edu NR 23 TC 46 Z9 48 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5861 J9 CATAL TODAY JI Catal. Today PD FEB 25 PY 2000 VL 56 IS 1-3 BP 297 EP 305 DI 10.1016/S0920-5861(99)00287-4 PG 9 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 289VC UT WOS:000085641800033 ER PT J AU Cumings, J Zettl, A AF Cumings, J Zettl, A TI Mass-production of boron nitride double-wall nanotubes and nanococoons (vol 316, pg 211, 2000) SO CHEMICAL PHYSICS LETTERS LA English DT Correction C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Zettl, A (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Cumings, John/A-3595-2012; Zettl, Alex/O-4925-2016 OI Zettl, Alex/0000-0001-6330-136X NR 1 TC 5 Z9 5 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD FEB 25 PY 2000 VL 318 IS 4-5 BP 497 EP 497 PG 1 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 289YV UT WOS:000085650300031 ER PT J AU Feldman, WC Lawrence, DJ Elphic, RC Barraclough, BL Maurice, S Genetay, I Binder, AB AF Feldman, WC Lawrence, DJ Elphic, RC Barraclough, BL Maurice, S Genetay, I Binder, AB TI Polar hydrogen deposits on the Moon SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID LUNAR PROSPECTOR; MERCURY RADAR; ICE; CLEMENTINE; NEUTRONS; ANOMALIES; IMAGES; POLES AB Neutron and gamma-ray data measured using the Lunar Prospector spectrometers were analyzed to define the enhanced hydrogen deposits near both poles of the Moon. Combining the new low-altitude neutron data (30 +/- 15 km) with previous high-altitude (100 +/- 20 km) neutron data and the results of several recent radar investigations sharply constrains the characteristics of each of the polar deposits. The deposits at the north appear to be in the form of many small pockets or of generally distributed hydrogen that average to a 100 ppm weight fraction enhancement over that which exists in regolith at more equatorial latitudes. Those deposits in the permanently shaded craters near the south pole are consistent with a thick ferroan anorthosite regolith containing an enhancement of 1670 +/- 890 ppm hydrogen, which, if in the form of water ice, amounts to 1.5 +/- 0.8% weight fraction of H2O. Neutron data alone cannot discriminate between hydrogen implanted in lunar soil from the solar wind, hydrated minerals, or H2O. These craters appear to be surrounded by regolith that either contains small pockets of enhanced hydrogen or is soil that is uniformly impregnated with hydrogen enhanced on average by about 100 ppm above that contained in soils at more equatorial latitudes. C1 Univ Calif Los Alamos Natl Lab, Grp NIS1, Los Alamos, NM 87545 USA. Observ Midi Pyrenees, F-31400 Toulouse, France. Lunar Res Inst, Gilroy, CA 95020 USA. RP Feldman, WC (reprint author), Univ Calif Los Alamos Natl Lab, Grp NIS1, POB 1663,MS D-466, Los Alamos, NM 87545 USA. RI Lawrence, David/E-7463-2015 OI Lawrence, David/0000-0002-7696-6667 NR 34 TC 158 Z9 158 U1 2 U2 11 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 FEB 25 PY 2000 VL 105 IS E2 BP 4175 EP 4195 DI 10.1029/1999JE001129 PG 21 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 287LG UT WOS:000085506900008 ER PT J AU Gasnault, O d'Uston, C Feldman, WC Maurice, S AF Gasnault, O d'Uston, C Feldman, WC Maurice, S TI Lunar fast neutron leakage flux calculation and its elemental abundance dependence SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID PROSPECTOR; ICE; MOON AB A numerical code has been developed to simulate fast neutron leakage flux from planetary surfaces. These neutrons are produced in copious number by interactions between galactic cosmic rays and the nuclei of surface material. Their leakage flux spectrum depends on the composition of the upper layers of planetary bodies. Measurement of these neutrons allows the mapping of major compositional units. This technique is successfully used on Lunar Prospector data to obtain global geochemical maps of the lunar surface. With the help of simulations, relations between soil composition and neutron fluxes in the fast energy range [500 keV, 10 MeV] are established. The numerical code reproduces correctly the measurements of fast neutrons over the Moon. Variation in the neutron flux between highland and mare soils is calculated. A simple formula is suggested to estimate quickly the integrated fast neutron leakage flux for a given soil composition. C1 Ctr Etud Spatiale Rayonnements, F-31028 Toulouse 4, France. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Observ Midi Pyrenees, F-31400 Toulouse, France. RP Gasnault, O (reprint author), Ctr Etud Spatiale Rayonnements, 9 Ave Colonel Roche,BP 4346, F-31028 Toulouse 4, France. RI Gasnault, Olivier/F-4327-2010 OI Gasnault, Olivier/0000-0002-6979-9012 NR 25 TC 24 Z9 27 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD FEB 25 PY 2000 VL 105 IS E2 BP 4263 EP 4271 DI 10.1029/1999JE001124 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 287LG UT WOS:000085506900013 ER PT J AU Lawson, SL Jakosky, BM Park, HS Mellon, MT AF Lawson, SL Jakosky, BM Park, HS Mellon, MT TI Brightness temperatures of the lunar surface: Calibration and global analysis of the Clementine long-wave infrared camera data SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article AB The scientific payload on the Clementine spacecraft included a long-wave infrared (LWIR) camera with a single passband centered at a wavelength of 8.75 mu m. The Clementine orbit deviated by +/-30 degrees from Sun synchronous, and for two lunar months, dayside nadir-looking images were obtained near local noon. During the systematic mapping phase of the Clementine mission, approximately 220,000 thermal-infrared images of the lunar surface were obtained. We have completed the calibration of the LWIR camera. Here we present the various steps involved in the calibration routine and the associated uncertainty analysis. The LWIR calibration routine can be outlined as follows: convert measured data number values to radiance via a calibration equation, subtract a zero-flux background image from each lunar image; divide by a flatfield frame; identify bad pixels; smooth over only bad pixels; adjust radiances to reflect the absolute calibration; and convert radiances to brightness temperatures via the Planck function. Observed LWIR radiances can be converted to brightness temperatures, which provide information on various physical properties of the lunar surface. We also present here the LWIR global data set. The LWIR data from noontime orbits demonstrate that the Lambertian temperature model of cos(1/4)(i)(i) is a fair approximation for nadir-looking temperatures, rather than the cos(1/6)(i) behavior observed for ground-based measurements of the full Moon. Deviations from the Lambertian model are likely due to surface roughness effects and variations in infrared emissivity. Tn addition, the LWIR global data set reveals the dayside lunar thermal emission to be largely governed by albedo and by the solar incidence angle. C1 Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Colorado, Dept Astrophys & Planetary Sci, Boulder, CO 80309 USA. Univ Colorado, Dept Geol Sci, Boulder, CO 80309 USA. RP Univ Colorado, Atmospher & Space Phys Lab, Campus Box 392, Boulder, CO 80309 USA. EM lawson@argyre.colorado.edu RI Mellon, Michael/C-3456-2016 NR 18 TC 35 Z9 46 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9097 EI 2169-9100 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD FEB 25 PY 2000 VL 105 IS E2 BP 4273 EP 4290 DI 10.1029/1999JE001047 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 287LG UT WOS:000085506900014 ER PT J AU Kielkopf, CL Ding, S Kuhn, P Rees, DC AF Kielkopf, CL Ding, S Kuhn, P Rees, DC TI Conformational flexibility of B-DNA at 0.74 angstrom resolution: d(CCAGTACTGG)(2) SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE B-DNA; DNA structure; ultrahigh resolution; nucleic acid structure; calcium binding ID T-G-G; X-RAY-DIFFRACTION; MINOR-GROOVE; CRYSTAL-STRUCTURE; ATOMIC-RESOLUTION; BASE-PAIRS; C-G; A-G; PROTEIN STRUCTURES; WATER-MOLECULES AB The affinity and specificity of a Ligand for its DNA site is a function of the conformational changes between the isolated and complexed states. Although the structures of a hydroxypyrrole-imidazole-pyrrole polyamide dimer with 5'-CCAGTACTGG-3' and the frp repressor recognizing the sequence 5'-GTACT-3' are known, the baseline conformation of the DNA site would contribute to our understanding of DNA recognition by these ligands. The 0.74 Angstrom resolution structure of a B-DNA double helix, 5'-CCAGTACTGG-3', has been determined by X-ray crystallography. Six of the nine phosphates, two of four bound calcium ions and networks of water molecules hydrating the oligonucleotide have alternate conformations. By contrast, nine of the ten bases have a single, unique conformation with hydrogen atoms visible in most cases. The polyamide molecules alter the geometry of the phosphodiester backbone, and the water molecules mediating contacts in the trp repressor/operator complex are conserved in the unliganded DNA. Furthermore, the multiple conformational states, ions and hydration revealed by this ultrahigh resolution structure of a B-form oligonucleotide are potentially general considerations for understanding DNA-binding affinity and specificity by ligands. (C) 2000 Academic Press. C1 CALTECH, Div Biol, Pasadena, CA 91125 USA. CALTECH, Div Chem & Chem Engn, Pasadena, CA 91125 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. CALTECH, Howard Hughes Med Inst, Pasadena, CA 91125 USA. RP Kielkopf, CL (reprint author), Rockefeller Univ, Dept Mol Biophys, 1230 York Ave, New York, NY 10021 USA. OI Kielkopf, Clara/0000-0002-7648-8271 NR 78 TC 84 Z9 87 U1 0 U2 3 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD FEB 25 PY 2000 VL 296 IS 3 BP 787 EP 801 DI 10.1006/jmbi.1999.3478 PG 15 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 291FY UT WOS:000085724500005 PM 10677281 ER PT J AU Schoehn, G Quaite-Randall, E Jimenez, JL Joachimiak, A Saibil, HR AF Schoehn, G Quaite-Randall, E Jimenez, JL Joachimiak, A Saibil, HR TI Three conformations of an archaeal chaperonin, TF55 from Sulfolobus shibatae SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE chaperone; archaea; electron cryo-microscopy; three-dimensional reconstruction ID T-COMPLEX POLYPEPTIDE-1; GROUP-II CHAPERONIN; ELECTRON-MICROSCOPY; MOLECULAR CHAPERONE; CRYSTAL-STRUCTURE; HEAT-SHOCK; IN-VITRO; PROTEIN; SOLFATARICUS; THERMOSOME AB Chaperonins are cylindrical, oligomeric complexes, essential for viability and required for the folding of other proteins. The GroE (group I) subfamily, found in eubacteria, mitochondria and chloroplasts, have 7-fold symmetry and provide an enclosed chamber for protein subunit folding. The central cavity is transiently closed by interaction with the co-protein, GroES. The most prominent feature specific to the group II subfamily, found in archaea and in the eukaryotic cytosol, is a long insertion in the substrate-binding region. In the archaeal complex, this forms an extended structure acting as a built-in lid, obviating the need for a GroES-like cofactor. This extension occludes a site known to bind non-native polypeptides in GroEL. The site and nature of substrate interaction are not known for the group II subfamily. The atomic structure of the thermosome, an archaeal group II chaperonin, has been determined in a fully closed form, but the entry and exit of protein substrates requires transient opening. Although an open form has been investigated by electron microscopy, conformational changes in group II chaperonins are not well characterized. Using electron cryo-microscopy and three-dimensional reconstruction, we describe three conformations of a group ii chaperonin, including an asymmetric, bullet-shaped form, revealing the range of domain movements in this subfamily. (C) 2000 Academic Press. C1 Univ London Birkbeck Coll, Dept Crystallog, London WC1E 7HX, England. Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. RP Saibil, HR (reprint author), Univ London Birkbeck Coll, Dept Crystallog, Malet St, London WC1E 7HX, England. NR 33 TC 62 Z9 64 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD FEB 25 PY 2000 VL 296 IS 3 BP 813 EP 819 DI 10.1006/jmbi.2000.3505 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 291FY UT WOS:000085724500007 PM 10677283 ER PT J AU Washburn, NR Stacy, AM Portis, AM AF Washburn, NR Stacy, AM Portis, AM TI Magnetic and transport properties of LaMn0.8Na0.2O3 SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID MAGNETORESISTANCE; TEMPERATURE; FILMS AB Structural, magnetic, and electrical properties are reported for the Na analogue of the doped manganites, La(1-x)A(x)MnO(3) (0.2 < x 0.5, A = Ca, Sr, Ba, Pb), prepared by precipitation from molten NaOH. Elemental analysis and diffraction data are consistent with the composition LaMn0.8Na0.2O3, indicating that Na substitutes almost exclusively onto the Mn sites of the perovskite structure. The magnetic and transport properties of this material have been investigated and it was found that, despite the substitution of a magnetically and electrically inert cation on the Mn site, LaMn0.8Na0.2O3 displays many of the same properties as the manganites doped with divalent cations on the La site. The main property differences are attributed to the strong structural and magnetic disorder that Na induces in LaMno.8Nao.203. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Washburn, NR (reprint author), Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. NR 25 TC 10 Z9 10 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 FEB 24 PY 2000 VL 104 IS 7 BP 1447 EP 1453 DI 10.1021/jp9929059 PG 7 WC Chemistry, Physical SC Chemistry GA 289EC UT WOS:000085606700006 ER PT J AU Alam, TM McLaughlin, J Click, CC Conzone, S Brow, RK Boyle, TJ Zwanziger, JW AF Alam, TM McLaughlin, J Click, CC Conzone, S Brow, RK Boyle, TJ Zwanziger, JW TI Investigation of sodium distribution in phosphate glasses using spin-echo Na-23 NMR SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID ALKALI SILICATE-GLASSES; NUCLEAR-MAGNETIC-RESONANCE; SHORT-RANGE STRUCTURE; SOLID-STATE NMR; P-31 MAS NMR; ULTRAPHOSPHATE GLASSES; METAPHOSPHATE GLASSES; LITHIUM; ENVIRONMENTS; SINGLE AB The spatial arrangements of sodium cations for a series of sodium phosphate glasses, xNa(2)O .(100-x)P2O5 (x less than or equal to 55), were investigated using Na-23 spin-echo NMR spectroscopy. The spin-echo decay rate is a function of the Na-Na homonuclear dipolar coupling. and is related to the spatial proximity of neighboring Na nuclei, The spin-echo decay rate in these sodium phosphate glasses increases nonlinearly with higher sodium number density. and thus provides a measure of the Na-Na extended range order, The results of these Na-23 NMR experiments are discussed within the context of several structural models, including a decimated crystal lattice model, cubic dilation lattice model, a hard sphere (HS) random distribution model, and a pairwise cluster hard sphere model, While the experimental Na-23 spin-echo M-2 are described :adequately by both the decimated lattice and the random HS models, it is demonstrated that the slight nonlinear behavior of M-2 as a function of sodium number density is more correctly described by the random distribution in the HS model. At low sodium number densities the experimental M-2 is inconsistent with models incorporating Na-Na clustering. The ability to distinguish between Na-Na clusters and nonclustered distributions becomes mon difficult at higher sodium concentrations. C1 Sandia Natl Labs, Dept Mat Aging & Reliabil, Albuquerque, NM 87185 USA. Indiana Univ, Dept Chem, Bloomington, IN 47405 USA. Univ Missouri, Dept Ceram Engn, Rolla, MO 65409 USA. Sandia Natl Labs, Dept Mat Proc, Adv Mat Lab, Albuquerque, NM 87106 USA. RP Alam, TM (reprint author), Sandia Natl Labs, Dept Mat Aging & Reliabil, POB 5800, Albuquerque, NM 87185 USA. NR 40 TC 23 Z9 23 U1 0 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD FEB 24 PY 2000 VL 104 IS 7 BP 1464 EP 1472 DI 10.1021/jp9931509 PG 9 WC Chemistry, Physical SC Chemistry GA 289EC UT WOS:000085606700008 ER PT J AU Olthof, B Khodakov, A Bell, AT Iglesia, E AF Olthof, B Khodakov, A Bell, AT Iglesia, E TI Effects of support composition and pretreatment conditions on the structure of vanadia dispersed on SiO2, Al2O3, TiO2, ZrO2, and HfO2 SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID OXIDE MONOLAYER CATALYSTS; RAMAN-SPECTROSCOPY; MOLECULAR-STRUCTURES; LASER RAMAN; V-51 NMR; V2O5; ZIRCONIA; SPECTRA; ALUMINA; STATE AB Spectroscopic techniques (X-ray absorption, Raman, and UV-visible) were utilized to monitor the effect of adsorbed water, calcination temperature, and reduction in H-2 on the structure of dispersed VOx for vanadia supported on SiO2, Al2O3. TiO2, ZrO2, and HfO2 prepared with VOx surface densities ranging from 0.46 VOx/nm(2) to 11.1 VOx/nm(2). Supported vanadia was found to exist as monovanadate. polyvanadate, or V2O5 species. the distribution among these species depending on the support for a given VOx surface density. Dehydration resulted in the appearance of monovanadate species on all supports, with the extent of these species decreasing in the order HfO2 > Al2O3 > ZrO2 > TiO2 > SiO2. Hydration of the samples caused a decrease in the monovanadate species and a slight increase in polyvanadate species. Oxidation at elevated temperature resulted in an increase in the crystallinity of V2O5 present on SiO2, a conversion of V2O5 into polyvanadate species on Al2O3, and the appearance of mixed-metal oxide phases on TiO2, ZrO2 (ZrV2O7), and HfO2 (HfV(2)O7). The appearance of an interaction between vanadia and titania coincides with the transformation from anatase to rutile TiO2. ZrV2O7 and HfV2O7 are postulated to form via the interaction of surface VOx species with the support as the support begins to undergo a phase transition from tetragonal to monoclinic. H-2 reduction produced limited changes in the structure of dispersed vanadia except on Al2O3, where V2O5 was transformed into polyvanadate species. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Bell, AT (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RI Khodakov, Andrei/I-3379-2014; Iglesia, Enrique/D-9551-2017; OI Khodakov, Andrei/0000-0003-4599-3969; Iglesia, Enrique/0000-0003-4109-1001; Bell, Alexis/0000-0002-5738-4645 NR 44 TC 141 Z9 142 U1 6 U2 48 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 FEB 24 PY 2000 VL 104 IS 7 BP 1516 EP 1528 DI 10.1021/jp9921248 PG 13 WC Chemistry, Physical SC Chemistry GA 289EC UT WOS:000085606700015 ER PT J AU Petrik, NG Knutsen, K Paparazzo, E Lea, S Camaioni, DM Orlando, TM AF Petrik, NG Knutsen, K Paparazzo, E Lea, S Camaioni, DM Orlando, TM TI Electron beam induced damage of NaNO3 single crystals: An energy, temperature, and quantum state resolved study SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID PHOTOELECTRON-SPECTROSCOPY; STIMULATED DESORPTION; SODIUM-NITRATE; NO3; DECOMPOSITION; DISSOCIATION; TRANSITION; DYNAMICS; EMISSION; CENTERS AB Electron beam induced damage of NaNO3 single crystals is examined using laser resonance enhanced multiphoton ionization detection of the neutral desorption products, post-irradiation temperature-programmed desorption (TPD), secondary electron emission microscopy (SEEM), and Auger electron spectroscopy (AES). The damage initially involves destruction of the nitrate group and production of O (P-3(J)) and NO ((2)Pi) fragments with nonthermal energy distributions. Specifically, the O (P-3(J)) J State distribution measured at 100 eV incident electron energy is 5:1.5:0.25 for J = 2:1:0, the NO ((2)Pi) vibrational state distribution is 1:0.56:0.35:0.40:0.23 for nu = 0:1:2:3:4, and the NO ((2)Pi(1/2,3/2)) rotational distribution has a high population of the upper ((2)Pi(3/2)) spin-orbit component. Production and desorption of these nonthermal fragments are dominated by the decay of {NO3-}*. At higher electron fluences, thermalized NO, O-2, and NO2 are also produced and released, though the NO2 is a minor product. We suggest that the formation and desorption of thermalized NO and O-2 both involve NO2- defect states and unimolecular dissociation of NO3*. This is supported by the observation that the NO and O-2 yields have the same temperature dependence which is well described by the sum of two Maxwell-Boltzmann type equations with activation energies of 0.16 +/- 0.03 and 0.010 +/- 0.004 eV. O-2 gas is also released in post-irradiation thermal cycling from 110 to 440 K with peaks at similar to 260 and similar to 340 K. We associate the post-irradiation TPD of O-2 With reactions involving O atoms released during thermal decomposition of (NO2-... O) and ONOO-. The SEEM image shows damage features, and the AES spectra indicate that the irradiated region is depleted in both nitrogen and oxygen relative to Na. The elemental composition shows Na2O as a final product of the NaNO3 radiation decomposition. The 100 eV electron beam damage cross section is at least similar to 10(-16) cm(2). C1 Pacific NW Lab, W R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Orlando, TM (reprint author), Pacific NW Lab, W R Wiley Environm Mol Sci Lab, POB 999,MS K8-88, Richland, WA 99352 USA. RI Petrik, Nikolay/G-3267-2015; OI Petrik, Nikolay/0000-0001-7129-0752; Lea, Alan/0000-0002-4232-1553 NR 56 TC 10 Z9 10 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD FEB 24 PY 2000 VL 104 IS 7 BP 1563 EP 1571 DI 10.1021/jp993310g PG 9 WC Chemistry, Physical SC Chemistry GA 289EC UT WOS:000085606700022 ER PT J AU Chu, K Vojtchovsky, J McMahon, BH Sweet, RM Berendzen, J Schlichting, I AF Chu, K Vojtchovsky, J McMahon, BH Sweet, RM Berendzen, J Schlichting, I TI Structure of a ligand-binding intermediate in wild-type carbonmonoxy myoglobin SO NATURE LA English DT Article ID MOLECULAR-DYNAMICS; PROTEINS; RELAXATION; MUTANTS; STATES; XENON; SITE AB Small molecules such as NO, O-2, CO or H-2 are important biological ligands that bind to metalloproteins to function crucially in processes such as signal transduction, respiration and catalysis. A key issue for understanding the regulation of reaction mechanisms in these systems is whether ligands gain access to the binding sites through specific channels and docking sites, or by random diffusion through the protein matrix. A model system for studying this issue is myoglobin, a simple haem protein. Myoglobin has been studied extensively by spectroscopy, crystallography, computation and theory(1-11). It serves as an aid to oxygen diffusion but also binds carbon mono nide, a byproduct of endogenous haem catabolism. Molecular dynamics simulations(3-5), random mutagenesis(6) and flash photolysis studies(7-10) indicate that ligand migration occurs through a limited number of pathways involving docking sites. Here we report the 1.4 Angstrom resolution crystal structure of a ligand-binding intermediate in carbonmonoxy myoglobin that may have far-reaching implications for understanding the dynamics of ligand binding and catalysis. C1 Univ Calif Los Alamos Natl Lab, Biophys Grp P21, Los Alamos, NM 87545 USA. Univ Vermont, Dept Phys, Burlington, VT 05405 USA. Max Planck Inst Mol Physiol, D-44227 Dortmund, Germany. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Chu, K (reprint author), Univ Calif Los Alamos Natl Lab, Biophys Grp P21, MS-D454, Los Alamos, NM 87545 USA. RI Schlichting, Ilme/I-1339-2013 NR 30 TC 204 Z9 208 U1 0 U2 15 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD FEB 24 PY 2000 VL 403 IS 6772 BP 921 EP 923 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 288JG UT WOS:000085559200065 PM 10706294 ER PT J AU Zhan, CG Landry, DW Ornstein, RL AF Zhan, CG Landry, DW Ornstein, RL TI Theoretical studies of fundamental pathways for alkaline hydrolysis of carboxylic acid esters in gas phase SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ELECTRON DETACHMENT ENERGIES; COCAINE CATALYTIC ANTIBODIES; PHENOLATE ION NUCLEOPHILES; TRANSITION-STATE STRUCTURE; ACETYL GROUP TRANSFER; CARBONYL-COMPOUNDS; BASIC SOLUTIONS; AQUEOUS-SOLUTION; AB-INITIO; FRAGMENTATION ENERGIES AB Fundamental reaction pathways for the alkaline hydrolysis of carboxylic acid esters, RCOOR', were examined through a series of first-principle calculations. The reactions of six representative esters with hydroxide ion were studied in the gas phase. A total of three competing reaction pathways were found and theoretically confirmed for each of the esters examined: bimolecular base-catalyzed acyl-oxygen cleavage (B(AC)2), bimolecular base-catalyzed alkyl-oxygen cleavage (B(AL)2), and carbonyl oxygen exchange with hydroxide. For the two-step B(AC)2 process, this is the first theoretical study to consider the individual sub-steps of the reaction process and to consider substituent effects. For the carbonyl oxygen exchange with hydroxide and for the one-step BAL2 process, we report here the first quantitative theoretical results for the reaction pathways and for the energy barriers. The energy barrier calculated for the second step of the B(AC)2 process, that is, the decomposition of the tetrahedral intermediate, is larger in the gas phase than that of the first step, that is, the formation of the tetrahedral intermediate, for all but one of the esters examined. The exception, CH3COOC(CH3)(3), does not have an alpha hydrogen in the leaving group. The highest energy barrier calculated for the B(AC)2 process is always lower than the barriers for the oxygen exchange and for the B(AL)2 process. The difference between the barrier for the B(AL)2 process and the highest barrier for the B(AC)2 process is only similar to 1-3 kcal/mol for the methyl esters, but becomes much larger for the others. Substitution of an alpha hydrogen in R' with a methyl group considerably increases the energy barrier for the B(AL)2 process, and significantly decreases the energy barrier for the second step of the B(AC)2 process. The calculated substituent shifts of the energy barrier for the first step of the B(AC)2 process in gas phase are in good agreement with the observed substituent shifts for the base-catalyzed hydrolysis of alkyl acetates in aqueous solution. All of the calculated results are consistent with the available experimental results and lead to a deeper understanding of previously reported gas-phase experimental observations. C1 Battelle NW, Pacific NW Natl Lab, Environm Technol Div, Richland, WA 99352 USA. Columbia Univ Coll Phys & Surg, Dept Med, New York, NY 10032 USA. RP Ornstein, RL (reprint author), Battelle NW, Pacific NW Natl Lab, Environm Technol Div, Richland, WA 99352 USA. NR 77 TC 57 Z9 59 U1 1 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD FEB 23 PY 2000 VL 122 IS 7 BP 1522 EP 1530 DI 10.1021/ja993311m PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 289TZ UT WOS:000085639200031 ER PT J AU Baranyai, A Cummings, PT AF Baranyai, A Cummings, PT TI Liquid-vapor coexistence by molecular dynamics simulation SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PHASE COEXISTENCE; GIBBS-ENSEMBLE; MONTE-CARLO; INTEGRATION; SYSTEMS AB We present a simple and consistent molecular dynamics algorithm for determining the equilibrium properties of a bulk liquid and its coexisting vapor phase. The simulation follows the dynamics of the two systems simultaneously while maintaining the volume and the number of particles of the composite system fixed. The thermostat can constrain either the total energy or the temperature at a desired value. Division of the extensive properties between the two phases is governed by the difference of the corresponding intensive state variables. Particle numbers are continuous variables and vary only in virtual sense, i.e., the real sizes of the two systems are the same and do not change during the course of the simulation. Calculation of the chemical potential is separate from the dynamics; thus, one can replace the particle exchange step with other method if it improves the efficiency of the code. (C) 2000 American Institute of Physics. [S0021-9606(00)50608-4]. C1 Eotvos Lorand Univ, Dept Theoret Chem, H-1518 Budapest 112, Hungary. Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Eotvos Lorand Univ, Dept Theoret Chem, POB 32, H-1518 Budapest 112, Hungary. EM baranyai@para.chem.elte.hu RI Cummings, Peter/B-8762-2013 OI Cummings, Peter/0000-0002-9766-2216 NR 17 TC 2 Z9 2 U1 0 U2 3 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 FEB 22 PY 2000 VL 112 IS 8 BP 3516 EP 3522 DI 10.1063/1.480506 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 284RD UT WOS:000085345300007 ER PT J AU Wang, LS Li, X AF Wang, LS Li, X TI Vibrationally resolved photoelectron spectroscopy of the first row transition metal and C-3 clusters: MC3- (M=Sc, V, Cr, Mn, Fe, Co, and Ni) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LANTHANUM-CARBON CLUSTERS; ELECTRONIC-STRUCTURE; THERMODYNAMIC PROPERTIES; SPECTRA; METALLOCARBOHEDRENES; CARBIDES; N=2-6; LACN AB We report photoelectron spectra of the MC3- clusters for M=Sc, V, Cr, Mn, Fe, Co, and Ni at two photon energies, 355 and 266 nm. Vibrational structure is resolved for the ground and excited state detachment transitions for all the clusters except for CoC3- and NiC3-. Electron affinity (EA) and vibrational frequencies for the MC3 clusters are obtained. Complicated low-lying excited state features are observed for all the species. We find that the trend of the EA across the 3d series for the MC3 clusters is similar to that of the MC2 species. The vibrational frequency is found to increase from ScC3 to TiC3 and then decreases monotonically to the right of the 3d series. Preliminary density functional theory calculations are performed on all the MC3 and MC3- clusters at several initial geometries and spin multiplicities. We find that the ground states of all the MC3 and MC3- species have C-2v ring structures. The calculated M-C stretching frequency for all the MC3 species is in good agreement with the experimental measurement, lending credence to the obtained C-2v structure. (C) 2000 American Institute of Physics. [S0021-9606(00)00308-1]. C1 Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Wang, LS (reprint author), Washington State Univ, Dept Phys, 2710 Univ Dr, Richland, WA 99352 USA. NR 28 TC 41 Z9 44 U1 0 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 22 PY 2000 VL 112 IS 8 BP 3602 EP 3608 DI 10.1063/1.480513 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 284RD UT WOS:000085345300015 ER PT J AU Boldyrev, AI Li, X Wang, LS AF Boldyrev, AI Li, X Wang, LS TI Vibrationally resolved photoelectron spectra of CuCN- and AgCN- and ab initio studies of the structure and bonding in CuCN SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-ORBITAL METHODS; POTENTIAL-ENERGY SURFACE; GAUSSIAN-BASIS SETS; ROTATIONAL SPECTRUM; ELECTRONIC-STRUCTURE; LITHIUM ISOCYANIDE; SPECTROSCOPY; CN; CYANIDE; ATOMS AB Vibrationally resolved photoelectron spectroscopy is combined with ab initio calculations to investigate the structure and chemical bonding in CuCN, CuCN-, AgCN, and AgCN-. The photoelectron spectra were measured at two photon energies, 532 and 355 nm and only detachment to the ground state of the neutral was observed at both detachment energies. The adiabatic electron affinity and metal-C vibrational frequency were obtained to be 1.466 (0.010) eV and 480(30) cm(-1), 1.588 (0.010) eV and 390(30) cm(-1) for CuCN and AgCN, respectively. In the ab initio calculations, both CuCN and CuCN- were found to have linear C-infinity V structures. Isocyanide CuNC and CuNC- were found to be 10.7 and 6.5 kcal/mol [at the CCSD(T)/6-311+G(3d)//CCSD(T)/6-311+G* level of theory] higher in energy. Cyclic structures were found to be transition states for the cyanide-isocyanide isomerization. The calculated electron binding energies and vibrational frequency are in good agreement with the experimental measurements. The combined experimental and theoretical efforts allow us to elucidate the structures of CuCN and CuCN-, and the nature of their chemical bonding. (C) 2000 American Institute of Physics. [S0021-9606(00)01808-0]. C1 Utah State Univ, Dept Chem & Biochem, Logan, UT 84322 USA. Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Boldyrev, AI (reprint author), Utah State Univ, Dept Chem & Biochem, Logan, UT 84322 USA. RI Boldyrev, Alexander/C-5940-2009 OI Boldyrev, Alexander/0000-0002-8277-3669 NR 57 TC 40 Z9 40 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 22 PY 2000 VL 112 IS 8 BP 3627 EP 3632 DI 10.1063/1.480516 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 284RD UT WOS:000085345300018 ER PT J AU Nyquist, RM Eberhardt, AS Silks, LA Li, Z Yang, X Swanson, BI AF Nyquist, RM Eberhardt, AS Silks, LA Li, Z Yang, X Swanson, BI TI Characterization of self-assembled monolayers for biosensor applications SO LANGMUIR LA English DT Article ID CHOLERA-TOXIN; PROTEIN ADSORPTION; FORCE MICROSCOPY; PHASE-BEHAVIOR; MOLECULAR RECOGNITION; GANGLIOSIDE GM1; LIPID-MEMBRANES; GOLD; BILAYERS; GLYCOL) AB Mixed monolayers of thiol-terminated poly(ethylene glycol) (PEG) and thioacetyl GM1 glycolipid on Au(lll) were examined utilizing atomic force microscopy, infrared spectroscopy, and grazing incidence X-ray diffraction to determine the composition, structure, and morphology and to characterize the specific and nonspecific interactions with protein. These monolayer architectures are robust and are readily controlled to provide a network of receptor GM1 in the PEG-terminated matrix. However, we also find significant levels of nonspecific and nonnative protein binding that reader this simplistic model system unsuitable for highly sensitive biosensor device applications. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Nyquist, RM (reprint author), Univ Illinois, Ctr Biophys & Computat Biol, 505 S Goodwin Ave, Urbana, IL 61801 USA. NR 51 TC 57 Z9 57 U1 0 U2 16 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD FEB 22 PY 2000 VL 16 IS 4 BP 1793 EP 1800 DI 10.1021/la990018r PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 285XA UT WOS:000085412600046 ER PT J AU Genzer, J Sivaniah, E Kramer, EJ Wang, JG Korner, H Char, K Ober, CK DeKoven, BM Bubeck, RA Fischer, DA Sambasivan, S AF Genzer, J Sivaniah, E Kramer, EJ Wang, JG Korner, H Char, K Ober, CK DeKoven, BM Bubeck, RA Fischer, DA Sambasivan, S TI Temperature dependence of molecular orientation on the surfaces of semifluorinated polymer thin films SO LANGMUIR LA English DT Article ID SMECTIC LIQUID-CRYSTAL; X-RAY REFLECTIVITY; BLOCK-COPOLYMERS; ISOTROPIC-PHASE; ORDER; SCATTERING; TENSION; STATE AB Near-edge X-ray absorption fine structure is used to investigate the temperature dependence of molecular orientation of semifluorinated liquid crystalline (SF-LC) mesogens, which are attached to the modified isoprene backbone of (i) a poly(1,2-isoprene) homopolymer and (ii) a diblock copolymer consisting of polystyrene and poly( 1,2-isoprene) blocks. Our experiments reveal the existence of two temperature regions in which the surface orientation of the SF-LC mesogens changes abruptly, but even 30 K above the highest such temperature region the surface orientation does not become isotropic. The lower temperature surface transition for both homopolymer and block copolymer occurs close to the temperature of the bulk homopolymer smectic-B to smectic-a transition and well above the bulk smectic-B to smectic-a transition in the block copolymer. It seems to be controlled exclusively by the ordering phenomena originating from the surface. In contrast, the change in the surface organization of the SF-LC mesogens at higher temperatures can be associated with the bulk LC transition from the smectic-ii to the isotropic phase. C1 Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA. Cornell Univ, Dept Mat Sci & Engn, Ithaca, NY 14853 USA. Dow Chem Co, Sci Analyt Lab, Midland, MI 48674 USA. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. Seoul Natl Univ, Dept Chem Engn, Seoul 151742, South Korea. RP Genzer, J (reprint author), N Carolina State Univ, Dept Chem Engn, Raleigh, NC 27695 USA. NR 26 TC 77 Z9 78 U1 1 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD FEB 22 PY 2000 VL 16 IS 4 BP 1993 EP 1997 DI 10.1021/la9910327 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 285XA UT WOS:000085412600072 ER PT J AU Markovic, NM Grgur, BN Lucas, CA Ross, PN AF Markovic, NM Grgur, BN Lucas, CA Ross, PN TI Surface chemistry of CO on Pt(100)-bimetallic surfaces: Displacement effects SO LANGMUIR LA English DT Article ID SINGLE-CRYSTAL SURFACES; INSITU INFRARED-SPECTROSCOPY; MONOXIDE ADLAYER STRUCTURES; SULFURIC-ACID-SOLUTION; LOW-INDEX PLATINUM; CARBON-MONOXIDE; UNDERPOTENTIAL DEPOSITION; FORMIC-ACID; ADSORPTION-ISOTHERMS; INTERFACE STRUCTURES AB The surface chemistry of coadsorbed CO and metal adatoms on the Pt(100) surface in acid electrolyte has been studied by means of rotating ring disk electrode (RRDE) measurements. These results showed that Cu and Pb adatoms are readily displaced from the Pt(100) surface by CO. The consequence of the observed displacement phenomenon is that the kinetics of the electrooxidation of CO on Pt(100) surfaces in Cu2+- (Pb2+-) containing solution is the same as in Cu2+- (Pb2+-) free solution. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Liverpool, Dept Phys, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. RP Markovic, NM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. OI Grgur, Branimir/0000-0003-4684-9053; Lucas, Christopher/0000-0001-5743-3868 NR 45 TC 11 Z9 11 U1 0 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD FEB 22 PY 2000 VL 16 IS 4 BP 1998 EP 2005 DI 10.1021/la990255u PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 285XA UT WOS:000085412600073 ER PT J AU Baker, SM Smith, GS Anastassopoulos, DL Toprakcioglu, C Vradis, AA Bucknall, DG AF Baker, SM Smith, GS Anastassopoulos, DL Toprakcioglu, C Vradis, AA Bucknall, DG TI Structure of polymer brushes under shear flow in a good solvent SO MACROMOLECULES LA English DT Article ID BROWNIAN DYNAMICS SIMULATION; COPOLYMER CHAINS; GRAFTED POLYMERS; DENSITY PROFILE; SURFACES; FORCES; LAYERS; INTERFACE C1 FORTH, GR-71110 Iraklion, Crete, Greece. Rutherford Appleton Lab, CLRC, ISIS Facil, Didcot OX11 0QX, Oxon, England. Los Alamos Natl Lab, LANSCE, Los Alamos, NM 87545 USA. Univ Patras, GR-26500 Patras, Greece. Harvey Mudd Coll, Claremont, CA 91711 USA. RP Toprakcioglu, C (reprint author), FORTH, POB 1527, GR-71110 Iraklion, Crete, Greece. RI Bucknall, David/F-7568-2016 OI Bucknall, David/0000-0003-4558-6933 NR 26 TC 47 Z9 47 U1 1 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD FEB 22 PY 2000 VL 33 IS 4 BP 1120 EP 1122 DI 10.1021/ma991499o PG 3 WC Polymer Science SC Polymer Science GA 286MM UT WOS:000085449800007 ER PT J AU Alam, TM Celina, M Assink, RA Clough, RL Gillen, KT Wheeler, DR AF Alam, TM Celina, M Assink, RA Clough, RL Gillen, KT Wheeler, DR TI Investigation of oxidative degradation in polymers using O-17 NMR spectroscopy SO MACROMOLECULES LA English DT Article ID NORMAL-HEXADECANE AUTOXIDATION; LIQUID-PHASE AUTOXIDATION; LUBRICANT DEGRADATION; THERMAL-DEGRADATION; REACTION PATHWAYS; ELEVATED-TEMPERATURES; ORGANIC-COMPOUNDS; PRODUCTS; POLYETHYLENE; MODEL AB The thermal oxidation of pentacontane (C50H102), and of the homopolymer polyisoprene, has been investigated using O-17 NMR spectroscopy. By performing the oxidation using O-17-labeled O-2 gas, it is possible to easily identify nonvolatile degradation products, even at relatively low concentrations. It is demonstrated that details of the degradation mechanism can be obtained from analysis of the O-17 NMR spectra as a function of total oxidation. Pentacontane reveals the widest variety of reaction products and exhibits changes in the relative product distributions with increasing O-2 consumption. At low levels of oxygen incorporation, peroxides are the major oxidation product, while at later stages of degradation these species are replaced by increasing concentrations of ketones, alcohols, carboxylic acids, and esters. Analyzing the product distribution can help in identification of the different free-radical decomposition pathways of hydroperoxides, including recombination, proton abstraction, and chain scission, as well as secondary reactions. The O-17 NMR spectra of thermally oxidized polyisoprene reveal fewer degradation functionalities but exhibit an increased complexity in the type of observed degradation species due to structural features such as unsaturation and methyl branching. Alcohols and ethers formed from hydrogen abstraction and free radical termination reactions are the dominant oxidation products. In polyisoprene, the formation of esters and carboxylic acids is relatively minor, distinctly different from the oxidation of pentacontane. An approximately linear increase in these degradation functionalities is observed with increasing oxidation levels. These results demonstrate the promise of O-17 NMR as a new technique for detailed investigation of oxidative polymer degradation. C1 Sandia Natl Labs, Dept Organ Mat, Albuquerque, NM 87185 USA. RP Alam, TM (reprint author), Sandia Natl Labs, Dept Organ Mat, Albuquerque, NM 87185 USA. NR 57 TC 27 Z9 28 U1 0 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD FEB 22 PY 2000 VL 33 IS 4 BP 1181 EP 1190 DI 10.1021/ma991061o PG 10 WC Polymer Science SC Polymer Science GA 286MM UT WOS:000085449800019 ER PT J AU Vogelgesang, R Grimsditch, M Wallace, JS AF Vogelgesang, R Grimsditch, M Wallace, JS TI The elastic constants of single crystal beta-Si3N4 SO APPLIED PHYSICS LETTERS LA English DT Article ID BRILLOUIN-SCATTERING; SILICON-NITRIDE; MECHANICAL-PROPERTIES; ELECTRONIC-STRUCTURE; DIAMOND AB Using Brillouin scattering, we have determined the complete set of elastic constants of the technologically important beta-Si3N4. Availability of single crystals has allowed us to measure all five independent c(ij), which (in units of GPa) are: c(11)=433(3), c(33)=574(3), c(13)=127(5), c(44)=108(2), c(66)=119(4), and c(12)=c(11)-2c(66)=195(8), giving a bulk modulus of 259. Our values are compared with existing calculations and c(ij) determined from nano-indentation results combined with empirical relations and trends in related materials. (C) 2000 American Institute of Physics. [S0003-6951(00)01608-9]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Vogelgesang, R (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Vogelgesang, Ralf/B-4460-2009 OI Vogelgesang, Ralf/0000-0002-1026-3205 NR 21 TC 66 Z9 66 U1 1 U2 16 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD FEB 21 PY 2000 VL 76 IS 8 BP 982 EP 984 DI 10.1063/1.125913 PG 3 WC Physics, Applied SC Physics GA 284QP UT WOS:000085343700014 ER PT J AU Hanna, MC Cheong, HM Mascarenhas, A AF Hanna, MC Cheong, HM Mascarenhas, A TI The initial stages of growth of CuPtB ordered Ga0.52In0.48P/GaAs and Ga0.47In0.53As/InP SO APPLIED PHYSICS LETTERS LA English DT Article ID VAPOR-PHASE EPITAXY; STEP STRUCTURE; V/III RATIO; SURFACE-TOPOGRAPHY; GAINP; HETEROSTRUCTURES; GA0.5IN0.5P; LAYERS; MICROSCOPY; PRECURSOR AB Atomic force microscopy and Raman spectroscopy were used to investigate the development of the surface morphology and ordering of Ga0.52In0.48P and Ga0.47In0.53As. A series of lattice-matched highly ordered Ga0.52In0.48P/GaAs and Ga0.47In0.53As/InP samples ranging in thickness from 2 to 50 nm were grown by low-pressure metalorganic vapor phase epitaxy on (001) direct and vicinal substrates. Raman spectroscopy provided direct evidence of CuPtB-type ordering in layers as thin as 10 nm for Ga0.52In0.48P and 5 nm for Ga0.47In0.53As. We find that the morphology of both Ga0.52In0.48P and Ga0.47In0.53As on (001)6B substrates consists of ridges with heights ranging from 2 to 10 nm, which are aligned predominately along the [110] direction. For Ga0.52In0.48P growth on (001) direct substrates, ridges similar to those obtained on 6B vicinal substrates form with no preferential orientation, while Ga0.47In0.53As growth on (001) direct substrates proceeds by a combination of two-dimensional-island and step-flow growth. The average roughness of the GaInP layers is approximately twice that of GaInAs layers. These findings suggest it may be difficult to produce abrupt large-area heterointerfaces in structures containing ordered Ga0.52In0.48P and Ga0.47In0.53As alloys. (C) 2000 American Institute of Physics. [S0003-6951(00)03408-2]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Hanna, MC (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Schaff, William/B-5839-2009; Cheong, Hyeonsik/D-7424-2012 OI Cheong, Hyeonsik/0000-0002-2347-4044 NR 31 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD FEB 21 PY 2000 VL 76 IS 8 BP 997 EP 999 DI 10.1063/1.125918 PG 3 WC Physics, Applied SC Physics GA 284QP UT WOS:000085343700019 ER PT J AU Kouznetsov, KA Borgmann, J Clarke, J AF Kouznetsov, KA Borgmann, J Clarke, J TI High-T-c second-order gradiometer for magnetocardiography in an unshielded environment (vol 75, pg 1979, 1999) SO APPLIED PHYSICS LETTERS LA English DT Correction C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Kouznetsov, KA (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD FEB 21 PY 2000 VL 76 IS 8 BP 1075 EP 1075 DI 10.1063/1.125943 PG 1 WC Physics, Applied SC Physics GA 284QP UT WOS:000085343700045 ER PT J AU Bakac, A Guzei, IA AF Bakac, A Guzei, IA TI Hydrogen atom and hydride transfer in the reactions of chromium(IV) and chromium(V) complexes with rhodium hydrides. Crystal structure of a superoxorhodium(III) product SO INORGANIC CHEMISTRY LA English DT Article ID AQUACHROMIUM(IV) ION; BOUND CHROMIUM(V); MOLECULAR-OXYGEN; METAL-COMPLEXES; REDUCTION; OXIDATION; DNA AB The aquachromyl ion, (CraqO2+)-O-IV, reacts with the hydrides L(H2O)RhH2+ (L = L-1 = [14]aneN(4) and L-2 = meso-Me-6-[14]aneN(4)) in aqueous solutions in the presence of molecular oxygen to yield Cr-aq(3+) and the superoxo complexes L(H2O)RhOO2+. At 25 degrees C, the rate constants are similar to 10(4) M-1 s(-1) (L = L-1) and 1.12 x 10(3) M-1 s(-1) (L = L-2). Both reactions exhibit a moderate deuterium isotope effect, k(RhH)/k(RhD) = similar to 3 (L-1) and 3.3 (L-2), but no solvent isotope effect, k(H2O)/k(D2O) = 1. The proposed mechanism involves hydrogen atom abstraction followed by the capture of LRh(H2O)(2+) with molecular oxygen. There is no evidence for the formation of L(H2O)Rh2+ in the reaction between L(H2O)RhH2+ and (salen)(CrO+)-O-V. The proposed hydride transfer is supported by the magnitude of the rate constants (L = L-1, k = 8800 M-1 s(-1); (NH3)(4), 2500; L-2, 1000) and isotope effects (L = L-1, kie = 5.4; L-2, 6.2). The superoxo complex [L-1(CH3CN)RhOO](CF3SO3)(2). H2O crystallizes with discrete anions, cations, and solvate water molecules in the lattice. All moieties are linked by a network of hydrogen bends of nine different types. The complex crystallized in the triclinic space group P (1) over bar with a = 9.4257(5) Angstrom, b = 13.4119(7) Angstrom, c = 13.6140(7) Angstrom, alpha = 72.842(1)degrees, beta = 82.082(1)degrees, gamma = 75.414(1)degrees, V = 1587.69(14) Angstrom(3), and Z = 2. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Bakac, A (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 28 TC 26 Z9 26 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD FEB 21 PY 2000 VL 39 IS 4 BP 736 EP 740 DI 10.1021/ic991098p PG 5 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 286WP UT WOS:000085472100018 PM 11272569 ER PT J AU Henning, RW Schultz, AJ Hitchman, MA Kelly, G Astley, T AF Henning, RW Schultz, AJ Hitchman, MA Kelly, G Astley, T TI Structural and EPR study of the dependence on deuteration of the Jahn-Teller distortion in ammonium hexaaquacopper(II) sulfate, (NH4)(2)[Cu(H2O)(6)](SO4)(2) SO INORGANIC CHEMISTRY LA English DT Article ID NEUTRON-DIFFRACTION; TUTTON SALT; ELECTRONIC-PROPERTIES; LOW-TEMPERATURE; COPPER(II) ION; PRESSURE; HYDROGEN AB The variation of the EPR spectra with degree of deuteration of the partially deuterated Tutton salt ammonium hexaaquacopper(II) sulfate, (NH4)(2)[Cu(H2O)(6)](SO4)(2), has been measured at 293 K. The measurements indicate that the structure changes quite abruptly from that of the purr: hydrogenous salt to that of the fully deuterated salt at similar to 50% deuteration. The structure of a crystal in which similar to 42% of the hydrogen atoms were replaced by deuterium was elucidated at 15 K by single-crystal time-of-flight neutron diffraction. The hexaaquacopper(II) complex exhibits an orthorhombically distorted, tetragonally elongated octahedral coordination geometry (Cu-O bond distances of 2.281(1), 2.007(1), and 1.975(1) Angstrom). The structure is very similar to that reported for the undeuterated salt at 9.6 K, and markedly different from that of the fully deuterated compound at 15 K, which has similar Cu-O bond lengths but with the directions of the long and intermediate bonds interchanged. There is no evidence for disorder or partial switching of the Cu-O bond directions. This is consistent with the temperature dependence of the EPR spectrum of the similar to 42% deuterated compound, which indicates a thermal equilibrium between the two structural forms close to room temperature similar to that reported for the undeuterated compound, but complete reversion to the low-temperature phase on cooling to 5 K. The possible influence of deuteration upon the hydrogen-bonding distances and the bearing of this upon the structural modifications of the compound are discussed. C1 Univ Tasmania, Sch Chem, Hobart, Tas 7001, Australia. Argonne Natl Lab, Argonne, IL 60439 USA. RP Schultz, AJ (reprint author), Univ Tasmania, Sch Chem, Box 252-75, Hobart, Tas 7001, Australia. NR 25 TC 16 Z9 16 U1 0 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD FEB 21 PY 2000 VL 39 IS 4 BP 765 EP 769 DI 10.1021/ic9910864 PG 5 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 286WP UT WOS:000085472100023 PM 11272574 ER PT J AU Kaskel, S Corbett, JD AF Kaskel, S Corbett, JD TI Synthesis and structure of K10Tl7: The first binary trielide containing naked pentagonal bipyramidal Tl-7 clusters SO INORGANIC CHEMISTRY LA English DT Article ID METALLIC ZINTL PHASE; COMPOUND; CS AB The title compound is synthesized by direct fusion of the elements at 400 degrees C followed by annealing at 330 degrees C, quenching to room temperature, and subsequent annealing at 120 and 100 degrees C for days to weeks. The compound crystallizes in the monoclinic space group P2(1)/c (No. 14), with Z = 4, a = 10.132(1) Angstrom, b = 22.323(2) Angstrom, c = 13.376(1) Angstrom, and beta = 93.14(1)degrees, and consists of Tl-7(7-) clusters embedded in a matrix of potassium ions. The cluster is an axially compressed pentagonal bipyramid close to D-5h symmetry. The apex-apex bond distance (3.462(1) Angstrom) is little longer than the bonds in the pentagonal waist (3.183(1)-3.247(1) Angstrom). Structurally the compound is not electron-precise: K10Tl7 has three extra electrons per Tl-7 cluster and is Pauli paramagnetic (chi(300) = 2.25 x 10(-4) emu/mol). C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Corbett, JD (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. RI Kaskel, Stefan/B-4200-2010; OI Kaskel, Stefan/0000-0003-4572-0303 NR 23 TC 24 Z9 24 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD FEB 21 PY 2000 VL 39 IS 4 BP 778 EP 782 DI 10.1021/ic991168s PG 5 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 286WP UT WOS:000085472100025 PM 11272576 ER PT J AU Barnes, CE Shin, Y Saengkerdsub, S Dai, S AF Barnes, CE Shin, Y Saengkerdsub, S Dai, S TI EXAFS study of uranyl nitrate dimer at high and low temperature SO INORGANIC CHEMISTRY LA English DT Article ID RAY-ABSORPTION-SPECTROSCOPY; CARBONATE COMPLEXES; LIMITATIONS; URANIUM; SOLIDS; WINXAS; RAMAN; NMR AB A uranium EXAFS study of the uranyl nitrate dimer [{UO2(mu-OH)(NO3)(2)}(2)](2-) at 10 and 294 K is described. Low-temperature data readily reveal the presence of the second uranium atom in the complex as well as distinguishing characteristics associated with the equatorial nitrate and bridging hydroxide groups. Observation and analysis of these critical components in EXAFS data collected at room temperature are much more difficult. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Barnes, CE (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RI Dai, Sheng/K-8411-2015 OI Dai, Sheng/0000-0002-8046-3931 NR 26 TC 14 Z9 14 U1 1 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD FEB 21 PY 2000 VL 39 IS 4 BP 862 EP + DI 10.1021/ic9904992 PG 4 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 286WP UT WOS:000085472100039 PM 11272590 ER PT J AU Bauer, ED Chau, R Dilley, NR Maple, MB Mandrus, D Sales, BC AF Bauer, ED Chau, R Dilley, NR Maple, MB Mandrus, D Sales, BC TI Pressure dependence of the electrical resistivity of the filled skutterudites LnFe(4)Sb(12) (Ln = Ce, Yb) SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID HEAVY-FERMION SYSTEMS; 2 ENERGY SCALES; PHYSICAL-PROPERTIES; LAFE4P12 STRUCTURE; ALKALINE-EARTH; ANTIMONIDES; SUPERCONDUCTIVITY; CEFE4SB12; URU2SI2; METALS AB We report the pressure dependence of the electrical resistivity of two filled skutterudite compounds YbFe4Sb12 and CeFe4Sb12 from 1.2 K up to room temperature and under applied pressures up to 17 kbar. Both YbFe4Sb12 and CeFe4Sb12 show a rapid decrease of rho at similar to 50 K and similar to 100 K, respectively, which is caused by the onset of coherent scattering of electrons from the rare-earth sublattice. The resistivity curves can be collapsed onto the ambient pressure curve using a single scaling temperature T-0, indicating that a single characteristic energy dominates the transport properties. For CeFe4Sb12, T-0 is found to increase with pressure, while the opposite behaviour is observed for YbFe4Sb12. The pressure dependence of rho as well as the change of T-0 are similar to the findings for a number of other intermediate-valence and heavy-fermion systems. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif San Diego, Inst Pure & Appl Phys Sci, La Jolla, CA 92093 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Bauer, ED (reprint author), Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RI Bauer, Eric/D-7212-2011; Mandrus, David/H-3090-2014 NR 29 TC 24 Z9 24 U1 1 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 FEB 21 PY 2000 VL 12 IS 7 BP 1261 EP 1267 DI 10.1088/0953-8984/12/7/310 PG 7 WC Physics, Condensed Matter SC Physics GA 318BX UT WOS:000087265000014 ER PT J AU Burov, A Nagaitsev, S AF Burov, A Nagaitsev, S TI Envelope instability as a source of diffusion SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Workshop on Electron Cooling and Related Topics (ECOOL 99)/5th Workshop on Medium Energy Electron Cooling CY MAY 19-22, 1999 CL UPPSALA, SWEDEN SP Royal Swedish Acad Sci, Swedish Nat Sci Res Council, Uppsala Univ DE electron cooling; lifetime; Fokker-Planck equation; intensity limit ID COOLER; BEAMS AB Electron cooling increases the phase space density of the cooled particles up to a certain limit. This limit is normally characterized by a strong space charge tune shift, about 0.2-0.3. This tune shift is high enough to bring the cooled beam to the threshold of the envelope instability. The envelope instability can be in a kind of dynamic equilibrium with the cooling, keeping the cooled beam at a threshold with a high level of the coherent noise. This noise acts as a diffusion for the halo particles which puts a limit on the stored current. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Burov, A (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 14 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 21 PY 2000 VL 441 IS 1-2 BP 18 EP 22 DI 10.1016/S0168-9002(99)01101-8 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 289ZN UT WOS:000085652000004 ER PT J AU Burov, A AF Burov, A TI Electron drift instability in storage rings with electron cooling SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Workshop on Electron Cooling and Related Topics (ECOOL 99)/5th Workshop on Medium Energy Electron Cooling CY MAY 19-22, 1999 CL UPPSALA, SWEDEN SP Royal Swedish Acad Sci, Swedish Nat Sci Res Council, Uppsala Univ DE ion beams; collective modes AB Transverse drift mobility of the cooling electrons allows them to respond to the transverse offset of the cooled beam. This electron dipole feedback introduces imaginary parts in transverse collective modes of the cooled beam. The sign of these imaginary parts is found to be dependent on the charge sign of the cooled particles, giving a coherent damping for protons and instability for antiprotons. A coupling between the transverse degrees of freedom of the stored cooled beam changes the result, causing an instability for any sign of the charge. For typical low-energy cooler parameters, these growth/damping times are found to be in the region 0.1-10 s. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Burov, A (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM burov@fnal.gov NR 7 TC 8 Z9 8 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 FEB 21 PY 2000 VL 441 IS 1-2 BP 23 EP 27 DI 10.1016/S0168-9002(99)01102-X PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 289ZN UT WOS:000085652000005 ER PT J AU Kjaergaard, N Aggerholm, S Bowe, P Hornekaer, L Madsen, N Nielsen, JS Schiffer, JP Siegfried, L Hangst, JS AF Kjaergaard, N Aggerholm, S Bowe, P Hornekaer, L Madsen, N Nielsen, JS Schiffer, JP Siegfried, L Hangst, JS TI Recent results from laser cooling experiments in ASTRID - real-time imaging of ion beams SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Workshop on Electron Cooling and Related Topics (ECOOL 99)/5th Workshop on Medium Energy Electron Cooling CY MAY 19-22, 1999 CL UPPSALA, SWEDEN SP Royal Swedish Acad Sci, Swedish Nat Sci Res Council, Uppsala Univ ID STORAGE-RING AB We describe the latest results from laser cooling experiments using Mg ions in the ASTRID storage ring. In particular, we focus on the transverse dynamics of the longitudinally cooled beam. We have developed a direct imaging technique, using the laser fluorescence to determine the horizontal and vertical distributions in the beam. The beam can now be imaged in real time, using an image intensifier and a fast-sampling CCD camera. The sensitivity and resolution of this system allow direct observation of beams which are well below the longitudinal charge density corresponding to a "string" of particles. We have observed space-charge limitations to the transverse beam sizes, as well as intriguing instabilities of very low-current beams. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Aarhus Univ, Inst Phys & Astron, DK-8000 Aarhus C, Denmark. CERN, CH-1211 Geneva, Switzerland. Argonne Natl Lab, Argonne, IL 60439 USA. RP Hangst, JS (reprint author), Aarhus Univ, Inst Phys & Astron, DK-8000 Aarhus C, Denmark. RI Kjaergaard, Niels/B-1806-2008; Madsen, Niels/G-3548-2013 OI Kjaergaard, Niels/0000-0002-7830-9468; Madsen, Niels/0000-0002-7372-0784 NR 6 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 FEB 21 PY 2000 VL 441 IS 1-2 BP 196 EP 202 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 289ZN UT WOS:000085652000035 ER PT J AU Madsen, N Bowe, P Drewsen, M Hornekaer, LH Kjaergaard, N Labrador, A Nielsen, JS Schiffer, JP Shi, P Hangst, JS AF Madsen, N Bowe, P Drewsen, M Hornekaer, LH Kjaergaard, N Labrador, A Nielsen, JS Schiffer, JP Shi, P Hangst, JS TI Density distribution in laser-cooled bunched beams SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Workshop on Electron Cooling and Related Topics (ECOOL 99)/5th Workshop on Medium Energy Electron Cooling CY MAY 19-22, 1999 CL UPPSALA, SWEDEN SP Royal Swedish Acad Sci, Swedish Nat Sci Res Council, Uppsala Univ DE laser-cooling; bunched beams; space-charge tune shift ID ION-BEAM AB Knowledge of the density distribution of a bunched beam is important for controlling and damping instabilities which often depend on the distribution function (A.W. Chao, in Physics of Collective Beam Instabilities in High Energy Accelerators, Wiley, New York, 1993). In this paper, experimental studies of the longitudinal bunch shapes and temperatures of laser-cooled bunched beams are presented. These studies are combined with measurements of the transverse density distribution of the beam using a novel technique (Madsen et al., Proceedings of the Sixth European Particle Accelerator Conference, EPAC'98, Stockholm, IOP Publishing, Bristol 1998, p. 1046). The bunch shapes for various temperatures comply with a model where the transverse temperature is assumed to be high. However, in the longitudinally space-charge limited case, it is observed that the maximum attainable density is much lower than it would be in a completely space-charge limited beam. Furthermore, it is observed that this maximum density decreases with increasing current. These observations might be important for the beam quality obtainable with laser-cooling. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Aarhus Univ, Inst Phys & Astron, DK-8000 Aarhus C, Denmark. Aarhus Univ, Inst Storage Ring Facil, DK-8000 Aarhus, Denmark. Argonne Natl Lab, Argonne, IL 60439 USA. RP Madsen, N (reprint author), CERN, Div PS, CH-1211 Geneva 23, Switzerland. RI Kjaergaard, Niels/B-1806-2008; Madsen, Niels/G-3548-2013 OI Kjaergaard, Niels/0000-0002-7830-9468; Madsen, Niels/0000-0002-7372-0784 NR 12 TC 2 Z9 2 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 21 PY 2000 VL 441 IS 1-2 BP 203 EP 208 DI 10.1016/S0168-9002(99)01134-1 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 289ZN UT WOS:000085652000036 ER PT J AU Burov, A MacLachlan, J Marriner, J Nagaitsev, S AF Burov, A MacLachlan, J Marriner, J Nagaitsev, S TI Scenario for electron cooling of antiprotons in the Recycler SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Workshop on Electron Cooling and Related Topics (ECOOL 99)/5th Workshop on Medium Energy Electron Cooling CY MAY 19-22, 1999 CL UPPSALA, SWEDEN SP Royal Swedish Acad Sci, Swedish Nat Sci Res Council, Uppsala Univ DE electron cooling; accumulator storage ring ID FERMILAB AB A system of electron cooling of antiprotons in the Recycler must satisfy certain conditions. Analytic and numeric calculations of the cooling process allow to specify these requirements. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Burov, A (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 11 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 21 PY 2000 VL 441 IS 1-2 BP 234 EP 240 DI 10.1016/S0168-9002(99)01138-9 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 289ZN UT WOS:000085652000040 ER PT J AU Nagaitsev, S Burov, A Crawford, AC Kroc, T MacLachlan, J Saewert, G Schmidt, CW Shemyakin, A Warner, A AF Nagaitsev, S Burov, A Crawford, AC Kroc, T MacLachlan, J Saewert, G Schmidt, CW Shemyakin, A Warner, A TI FNAL R&D in medium energy electron cooling SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Workshop on Electron Cooling and Related Topics (ECOOL 99)/5th Workshop on Medium Energy Electron Cooling CY MAY 19-22, 1999 CL UPPSALA, SWEDEN SP Royal Swedish Acad Sci, Swedish Nat Sci Res Council, Uppsala Univ DE accelerator; electron beam; electron cooling AB The first stage of the Fermilab Electron Cooling R&D program is now complete: a technology necessary to generate hundreds of milliamps of electron beam current at MeV energies has been demonstrated. Conceptual design studies show that with an electron beam current of 200 mA and with a cooling section of 20 m electron cooling in the 8.9 GeV/c Fermilab Recycler ring can provide antiproton stacking rates suitable for the Tevatron upgrades beyond Run II luminosity goals. A novel electron beam transport scheme with a weak magnetic field at the cathode and in the cooling section, and with discrete focusing elements in between will be used. A prototype of such an electron cooling system is now being built at Fermilab as part of the continuing R&D program. This paper describes the status of the electron cooling R&D program at Fermilab. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Nagaitsev, S (reprint author), Fermi Natl Accelerator Lab, Fermilab MS 307, Batavia, IL 60510 USA. NR 7 TC 17 Z9 17 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 21 PY 2000 VL 441 IS 1-2 BP 241 EP 245 DI 10.1016/S0168-9002(99)01139-0 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 289ZN UT WOS:000085652000041 ER PT J AU Nagaitsev, S Saewert, G Shemyakin, A Warner, A AF Nagaitsev, S Saewert, G Shemyakin, A Warner, A TI Diagnostics for the 5 MeV electron cooling system SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Workshop on Electron Cooling and Related Topics (ECOOL 99)/5th Workshop on Medium Energy Electron Cooling CY MAY 19-22, 1999 CL UPPSALA, SWEDEN SP Royal Swedish Acad Sci, Swedish Nat Sci Res Council, Uppsala Univ DE accelerator; electron beam; electron cooling; beam diagnostics AB A prototype of a novel electron cooling system that will operate in the MeV energy range is now being built at Fermilab. This system will have very stringent beam optics requirements. To meet these requirements, beam diagnostics that allow measuring a beam position to 50 mu m in 1 Hz BW and a beam diameter to 0.1 mm out of 1 cm needs to be developed. In this paper we describe various possible diagnostics, discuss their limitations and preliminary test results. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Nagaitsev, S (reprint author), Fermi Natl Accelerator Lab, Fermilab MS 307,POB 500, Batavia, IL 60510 USA. NR 5 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 21 PY 2000 VL 441 IS 1-2 BP 246 EP 254 DI 10.1016/S0168-9002(99)01140-7 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 289ZN UT WOS:000085652000042 ER PT J AU Burov, A Danilov, V Colestock, P Derbenev, Y AF Burov, A Danilov, V Colestock, P Derbenev, Y TI Electron cooling for RHIC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Workshop on Electron Cooling and Related Topics (ECOOL 99)/5th Workshop on Medium Energy Electron Cooling CY MAY 19-22, 1999 CL UPPSALA, SWEDEN SP Royal Swedish Acad Sci, Swedish Nat Sci Res Council, Uppsala Univ DE RHIC; electron cooling; ion beams AB Electron cooling of completely stripped gold ions (197)AU(79+) in RHIC is considered for the store energy, gamma = 108. The optimal parameters of the required electron storage ring are discussed and proposed. The cooling time is calculated as 15 min, which would allow not only to avoid the beam loss due to the intra-beam scattering, but also reduce the transverse emittance and increase the luminosity several times. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Michigan State Univ, E Lansing, MI 48824 USA. RP Burov, A (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 5 TC 4 Z9 4 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 FEB 21 PY 2000 VL 441 IS 1-2 BP 271 EP 273 DI 10.1016/S0168-9002(99)01144-4 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 289ZN UT WOS:000085652000046 ER PT J AU Sternlicht, MD Bissell, MJ Werb, Z AF Sternlicht, MD Bissell, MJ Werb, Z TI The matrix metalloproteinase stromelysin-1 acts as a natural mammary tumor promoter SO ONCOGENE LA English DT Article DE matrix metalloproteinases; stromelysin; TIMP; mammary carcinogenesis; epithelial-to-mesenchymal conversion ID HUMAN BREAST-CANCER; ERYTHROID-POTENTIATING ACTIVITY; MESSENGER-RNA EXPRESSION; TIMP-1 TRANSGENIC MICE; TISSUE INHIBITOR; GROWTH-FACTOR; EPITHELIAL-CELLS; IN-VIVO; INTESTINAL TUMORIGENESIS; DISTANT METASTASES AB Extracellular matrix-degrading matrix metalloproteinases (MMPs) ape invariably upregulated in epithelial cancers and are key agonists in angiogenesis, invasion and metastasis. Yet most MMPs are secreted not by the cancer cells themselves, but by stromal cells within and around the tumor mass. Because the stromal environment can influence tumor formation, and because MMPs can alter this environment, MMPs may also contribute to the initial stages of cancer development. Several recent studies in MMP-overexpressing and MMP-deficient mice support this possibility, but have required carcinogens or pre-existing oncogenic mutations to initiate tumorigenesis. Here we review the spontaneous development of premalignant and malignant lesions in the mammary glands of transgenic mice that express an autoactivating form of MMP3/stromelysin-1 under the control of the whey acidic protein gene promoter. These changes were absent in nontransgenic littermates and were quenched by co-expression of a human tissue inhibitor of metalloproteinases-1 (TIMP-1) transgene, Thus by altering the cellular microenvironment, stromelysin-l can act res a natural tumor promoter and enhance cancer susceptibility. C1 Univ Calif San Francisco, Dept Anat, San Francisco, CA 94143 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Sternlicht, MD (reprint author), Univ Calif San Francisco, Dept Anat, 513 Parnassus Ave,HSW-1301, San Francisco, CA 94143 USA. FU NCI NIH HHS [CA57621, CA72006, P01 CA072006, P01 CA072006-07, R01 CA057621, R01 CA057621-07] NR 98 TC 174 Z9 182 U1 0 U2 10 PU STOCKTON PRESS PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 0950-9232 J9 ONCOGENE JI Oncogene PD FEB 21 PY 2000 VL 19 IS 8 SI SI BP 1102 EP 1113 DI 10.1038/sj.onc.1203347 PG 12 WC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity GA 292LT UT WOS:000085796400019 PM 10713697 ER PT J AU Avens, LR Burns, CJ Butcher, RJ Clark, DL Gordon, JC Schake, AR Scott, BL Watkin, JG Zwick, BD AF Avens, LR Burns, CJ Butcher, RJ Clark, DL Gordon, JC Schake, AR Scott, BL Watkin, JG Zwick, BD TI Mono(pentamethylcyclopentadienyl)uranium(III) complexes: Synthesis, properties, and X-ray structures of (eta-C5Me5)UI2(THF)(3), (eta-C5Me5)UI2(py)(3), and (eta-C5Me5)U[N(SiMe3)(2)](2) SO ORGANOMETALLICS LA English DT Review ID TRIVALENT URANIUM CHEMISTRY; HYDROGEN-DEUTERIUM EXCHANGE; TERT-BUTYL ISOCYANIDE; MOLECULAR-STRUCTURE; CRYSTAL-STRUCTURE; ALKOXIDE CHEMISTRY; ORGANOMETALLIC CHEMISTRY; CARBON-MONOXIDE; ACTINIDE; CYCLOPENTADIENYL AB The uranium(III) iodide complex UI3(THF)(4) reacts cleanly at ambient temperature with 1 equiv of sodium and potassium pentamethylcyclopentadienide salts in tetrahydrofuran to form the mono-ring uranium(III) complex (eta-C5Me5)UI2(THF)(3) (1). Additionally, reaction of UI3(THF)(4) with 2 equiv or more of K(C5Me5) in THF solution leads to the formation of the bis-ring adduct (r-C5Me5)(2)UI(THF) (2) in high yield. In the solid state 1 exhibits a pseudooctahedral mer,trans ligand geometry with the C5Me5 ligand occupying one axial position. U-I bond lengths range from 3.161(1) to 3.179(1)Angstrom while U-O distances to the THF ligands lie in the range 2.496(8)-2.594(10) Angstrom. 1 also provides a convenient entry into a variety of other mono-ring complexes of uranium(III). In the presence of excess pyridine, the coordinated THF ligands of 1 are readily displaced to form the tris(pyridine) adduct (eta-C5Me5)UI2(PY)(3) (3), which exhibits a mer,tp ans ligand geometry in the solid state similar to that of 1. Metathesis of the iodide ligands in 1 with 2 equiv of KN(SiMe3)(2) affords the bis(amido) complex (eta-C5Me5)U[N(SiMe3)(2)](2) (4). An X-ray diffraction study of this molecule reveals that methyl groups from both amido ligands are involved in agostic interactions with the uranium(III) center. C1 Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Chem Sci & Technol, Los Alamos, NM 87545 USA. Howard Univ, Dept Chem, Washington, DC 20059 USA. RP Burns, CJ (reprint author), Univ Calif Los Alamos Natl Lab, GT Seaborg Inst, POB 1663, Los Alamos, NM 87545 USA. RI Clark, David/A-9729-2011; Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 68 TC 55 Z9 55 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD FEB 21 PY 2000 VL 19 IS 4 BP 451 EP 457 DI 10.1021/om990718r PG 7 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 286MY UT WOS:000085450800012 ER PT J AU Yang, H Gao, HR Angelici, RJ AF Yang, H Gao, HR Angelici, RJ TI Hydrogenation of arenes under mild conditions using rhodium pyridylphosphine and bipyridyl complexes tethered to a silica-supported palladium heterogeneous catalyst SO ORGANOMETALLICS LA English DT Article ID ASYMMETRIC TRANSFER HYDROGENATION; RANEY-NICKEL CATALYSTS; RAY CRYSTAL-STRUCTURE; RUTHENIUM(II) COMPLEXES; SELECTIVE HYDROGENATION; AROMATIC-HYDROCARBONS; BENZENE-DERIVATIVES; PHASE HYDROGENATION; ARYLOXIDE COMPOUNDS; ORGANIC-SYNTHESIS AB The rhodium complexes [Rh(COD)(1)]BF4 (Rh(N-P)) and [Rh(COD)(2)]BF4 (Rh(N-N)), containing the new pyridylphosphine and bipyridyl ligands (1 and 2) with alkoxysilane groups, were tethered on the silica-supported palladium heterogeneous catalyst Pd-SiO2 to give the TCSM (tethered complex on supported metal) catalysts Rh(N-P)/Pd-SiO2 and Rh(N-N)/Pd-SiO2. Under the mild conditions of 70 degrees C and 4 atm of Hp, the two TCSM catalysts are very active for the hydrogenation of arenes (PhCO2Me, PhOH, toluene, PhOCH3, PhCO2Et, 4-CH3C6H4CO2Et, dimethyl terephthalate) to cyclohexanes; the activities are higher than those of the separate homogeneous Rh(N-P) and Rh(N-N) complex catalysts, the silica-supported palladium catalyst Pd-SiO2, or the rhodium complex catalysts tethered on just SiO2. The catalysts are easily separated from the reaction mixtures and can be recycled several times without losing activity. Of the two TCSM catalysts, the higher activity for the hydrogenation of anisole to methyl cyclohexyl ether was observed for Rh(N-N)/Pd-SiO2, which gives a TOF value of 3060 mol of substrate converted/((mol of Rh) h) and a TO value of 14 500 mol of substrate converted/(mol of Rh) in 6 h. Reactions of acetophenone lead to hydrogenation of the arene ring, the carbonyl group, or both, depending on the catalyst (Rh(N-P)/Pd-SiO2 or Rh(N-N)/Pd-SiO2) and the solvent (heptane or ethanol). C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 86 TC 86 Z9 87 U1 2 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 EI 1520-6041 J9 ORGANOMETALLICS JI Organometallics PD FEB 21 PY 2000 VL 19 IS 4 BP 622 EP 629 DI 10.1021/om990713u PG 8 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 286MY UT WOS:000085450800031 ER PT J AU Sonzogni, AA Rehm, KE Ahmad, I Borasi, F Bowers, DL Brumwell, F Caggiano, J Davids, CN Greene, JP Harss, B Heinz, A Henderson, D Janssens, RVF Jiang, CL McMichael, G Nolen, J Pardo, RC Paul, M Schiffer, JP Segel, RE Seweryniak, D Siemssen, RH Truran, JW Uusitalo, J Wiedenhover, I Zabransky, B AF Sonzogni, AA Rehm, KE Ahmad, I Borasi, F Bowers, DL Brumwell, F Caggiano, J Davids, CN Greene, JP Harss, B Heinz, A Henderson, D Janssens, RVF Jiang, CL McMichael, G Nolen, J Pardo, RC Paul, M Schiffer, JP Segel, RE Seweryniak, D Siemssen, RH Truran, JW Uusitalo, J Wiedenhover, I Zabransky, B TI The Ti-44(alpha, p) reaction and its implication on the Ti-44 yield in supernovae SO PHYSICAL REVIEW LETTERS LA English DT Article ID RAY LINE EMISSION; HALF-LIFE; CROSS-SECTIONS AB Cross sections for the Ti-44(alpha, p)V-47 reaction which significantly affects the yield of Ti-41 in supernovae were measured in the energy range 5.7 MeV less than or equal to E-c.m. less than or equal to 9 MeV, using a beam of radioactive Ti-44. The cross sections and the deduced astrophysical reaction rates are larger than the results from theoretical calculations by about a factor of 2. The implications of this increase in the reaction rate for the search of supernovae using space-based gamma detectors are discussed. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Northwestern Univ, Evanston, IL 60208 USA. Hebrew Univ Jerusalem, Jerusalem, Israel. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. RP Sonzogni, AA (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Heinz, Andreas/E-3191-2014 NR 27 TC 35 Z9 35 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD FEB 21 PY 2000 VL 84 IS 8 BP 1651 EP 1654 DI 10.1103/PhysRevLett.84.1651 PG 4 WC Physics, Multidisciplinary SC Physics GA 285HK UT WOS:000085383500004 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Bedeschi, F Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bevensee, B Bhatti, A Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, BS Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlson, J Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chapman, J Chen, C Chen, YC Cheng, MT Chertok, M Chiarelli, G Chirikov-Zorin, I Chlachidze, G Chlebana, F Christofek, L Chu, ML Cihangir, S Ciobanu, CI Clark, AG Cobal, M Cocca, E Connolly, A Conway, J Cooper, J Cordelli, M da Costa, JG Costanzo, D Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Geer, S Gerdes, DW Giannetti, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Green, C Groer, L Grosso-Pilcher, C Guenther, M Guillian, G Guo, RS Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kirk, M 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 Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, M Latino, G LeCompte, T Lee, AM Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Meschi, E Mesropian, C Miao, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Moggi, N Moore, E Moore, R Morita, Y Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nicolaidi, P Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Parri, A Partos, D Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Riegler, W Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Signorelli, G Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takashima, R Takikawa, K Tanaka, M Takano, T Tannenbaum, B Taylor, W Tecchio, M Teng, PK Terashi, K Tether, S Theriot, D Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Vologouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Zanetti, A Zetti, F Zucchelli, S AF Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Bedeschi, F Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bevensee, B Bhatti, A Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, BS Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlson, J Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chapman, J Chen, C Chen, YC Cheng, MT Chertok, M Chiarelli, G Chirikov-Zorin, I Chlachidze, G Chlebana, F Christofek, L Chu, ML Cihangir, S Ciobanu, CI Clark, AG Cobal, M Cocca, E Connolly, A Conway, J Cooper, J Cordelli, M da Costa, JG Costanzo, D Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Geer, S Gerdes, DW Giannetti, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Green, C Groer, L Grosso-Pilcher, C Guenther, M Guillian, G Guo, RS Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kirk, M 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 Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, M Latino, G LeCompte, T Lee, AM Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Meschi, E Mesropian, C Miao, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Moggi, N Moore, E Moore, R Morita, Y Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nicolaidi, P Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Parri, A Partos, D Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Riegler, W Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Signorelli, G Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takashima, R Takikawa, K Tanaka, M Takano, T Tannenbaum, B Taylor, W Tecchio, M Teng, PK Terashi, K Tether, S Theriot, D Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Vologouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Zanetti, A Zetti, F Zucchelli, S TI Measurement of b-quark fragmentation fractions in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID SILICON VERTEX DETECTOR; BRANCHING FRACTIONS; E+E ANNIHILATION; GAUGE THEORIES; Z-DECAYS; LIFETIME; MODEL AB We have studied the production of B hadrons in 1.8-TeV collisions. We present measurements of the fragmentation fractions, f(u), f(d), f(s), and f(baryon), of produced b quarks that yield B+, B-0, B-s(0), and <(Lambda)over bar(b)(0)> hadrons. Reconstruction of five electron-charm final states yields f(s)/(f(u) + f(d)) = 0.213 +/- 0.068 and f(baryon)/(f(u) + f(d)) = 0.118 +/- 0.042, assuming f(u) = f(d). If all B hadrons produced in collisions cascade to one of these four hadrons, we determine f(u) = f(d) = 0.375 +/- 0.023, f(s) = 0.160 +/- 0.044, and f(baryon) = 0.090 +/- 0.029. If we do not assume f(u) = f(d), we find f(d)/f(u) = 0.84 +/- 0.16. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Cantabria, Inst Fis Cantabria, Santander 39005, Spain. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Nucl Res Inst, RU-141980 Dubna, Russia. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Kyungpook Natl Univ, Korean Hadron Collider Lab, Taegu 702701, South Korea. Seoul Natl Univ, Seoul 151742, South Korea. Sungkyunkwan Univ, Suwon 440746, South Korea. High Energy Accelerator Res Org, Tsukuba, Ibaraki 305, Japan. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, Sezione Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 305, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Affolder, T (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Scodellaro, Luca/K-9091-2014; Paulini, Manfred/N-7794-2014; Prokoshin, Fedor/E-2795-2012; Introzzi, Gianluca/K-2497-2015; vilar, rocio/D-7454-2014 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787; Prokoshin, Fedor/0000-0001-6389-5399; Introzzi, Gianluca/0000-0002-1314-2580; NR 22 TC 29 Z9 29 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 FEB 21 PY 2000 VL 84 IS 8 BP 1663 EP 1668 DI 10.1103/PhysRevLett.84.1663 PG 6 WC Physics, Multidisciplinary SC Physics GA 285HK UT WOS:000085383500007 PM 21923205 ER PT J AU Melnikov, K van Ritbergen, T AF Melnikov, K van Ritbergen, T TI Three-loop slope of the Dirac form factor and the 1S Lamb shift in hydrogen SO PHYSICAL REVIEW LETTERS LA English DT Article ID ATOMIC-HYDROGEN; ENERGY-LEVELS; DEUTERIUM; FREQUENCY AB The last unknown contribution to hydrogen energy levels at order m alpha(7), due to the slope of the Dirac form factor at three loops, is evaluated in a closed analytical form. The resulting shift of the hydrogen nS energy level is found to be 3.016/n(3) kHz. Using the QED calculations of the 1S Lamb shift, we extract a precise value of the proton charge radius r(p) = 0.883 +/- 0.014 fm. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Karlsruhe, Inst Theoret Teilchenphys, D-76128 Karlsruhe, Germany. RP Melnikov, K (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 27 TC 73 Z9 73 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD FEB 21 PY 2000 VL 84 IS 8 BP 1673 EP 1676 DI 10.1103/PhysRevLett.84.1673 PG 4 WC Physics, Multidisciplinary SC Physics GA 285HK UT WOS:000085383500009 PM 21923206 ER PT J AU Diehl, S Cubaynes, D Zhou, HL VoKy, L Wuilleumier, FJ Kennedy, ET Bizau, JM Manson, ST Morgan, TJ Blancard, C Berrah, N Bozek, J AF Diehl, S Cubaynes, D Zhou, HL VoKy, L Wuilleumier, FJ Kennedy, ET Bizau, JM Manson, ST Morgan, TJ Blancard, C Berrah, N Bozek, J TI Angle-resolved photoelectron spectrometry studies of the autoionization of the 2s(2)2p P-2 triply excited state of atomic lithium: Experimental results and R-matrix calculations SO PHYSICAL REVIEW LETTERS LA English DT Article ID ANGULAR-DISTRIBUTIONS; HOLLOW LITHIUM; RESOLUTION; PHOTOEXCITATION; SPECTROSCOPY; RESONANCES; HELIUM; SHELL AB We have measured the angle-resolved energy dependence of the electrons emitted over the energy range of the triply excited 2s(2)2p P-2 lithium resonance using synchrotron radiation. We have also calculated the behavior of the angular distribution parameter beta using the R-matrix approximation. Experimental and theoretical results are in good agreement and show deep minima in the 1s2p P-1,P-3 ionic channels, The energy at which the minima occur does not coincide with the resonance energy, but is shifted towards higher energy. C1 Univ Paris Sud, Lab Spect Atom & Ion, UMR 8624 CNRS, F-91405 Orsay, France. Georgia State Univ, Dept Phys & Astron, Atlanta, GA 30303 USA. Observ Cote Azur, F-06304 Nice, France. Dublin City Univ, Sch Phys Sci, Dublin 9, Ireland. Wesleyan Univ, Dept Phys, Middletown, CT 06459 USA. CEA, DAM, DPTA, F-91680 Bruyeres Le Chatel, France. Western Michigan Univ, Dept Phys, Kalamazoo, MI USA. Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Lab, Berkeley, CA USA. RP Diehl, S (reprint author), Univ Paris Sud, Lab Spect Atom & Ion, UMR 8624 CNRS, B350, F-91405 Orsay, France. RI Bozek, John/E-4689-2010; Bozek, John/E-9260-2010 OI Bozek, John/0000-0001-7486-7238 NR 21 TC 32 Z9 32 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 FEB 21 PY 2000 VL 84 IS 8 BP 1677 EP 1680 DI 10.1103/PhysRevLett.84.1677 PG 4 WC Physics, Multidisciplinary SC Physics GA 285HK UT WOS:000085383500010 ER PT J AU Gao, HJ Sohlberg, K Xue, ZQ Chen, HY Hou, SM Ma, LP Fang, XW Pang, SJ Pennycook, SJ AF Gao, HJ Sohlberg, K Xue, ZQ Chen, HY Hou, SM Ma, LP Fang, XW Pang, SJ Pennycook, SJ TI Reversible, nanometer-scale conductance transitions in an organic complex SO PHYSICAL REVIEW LETTERS LA English DT Article ID SCANNING TUNNELING MICROSCOPE; MOLECULAR-ORBITAL METHODS; INDUCED PHASE-TRANSITION; VALENCE BASIS-SETS; RADICAL-ION SALTS; CONJUGATED POLYMERS; INFRARED-SPECTRUM; THIN-FILMS; ELEMENTS; SILVER AB Reversible conductance transitions are demonstrated on the molecular scale in a complex of 3-nitrobenzal malononitrile and 1,4-phenylenediamine, by application of local electric field pulses. Both macroscopic and local current-voltage (I/V) measurements show similar electrical bistability behavior. The mechanism of the electrical bistability is discussed. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Chinese Acad Sci, Inst Phys, Beijing Lab Vacuum Phys, Beijing 100080, Peoples R China. Chinese Acad Sci, Ctr Condensed Matter Phys, Beijing 100080, Peoples R China. Univ Chicago, Dept Biochem & Mol Biol, Chicago, IL 60637 USA. RP Gao, HJ (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Hou, Shimin/B-1556-2013 NR 33 TC 161 Z9 178 U1 1 U2 23 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD FEB 21 PY 2000 VL 84 IS 8 BP 1780 EP 1783 DI 10.1103/PhysRevLett.84.1780 PG 4 WC Physics, Multidisciplinary SC Physics GA 285HK UT WOS:000085383500036 ER PT J AU Morozov, N Krusin-Elbaum, L Shibauchi, T Bulaevskii, LN Maley, MP Latyshev, YI Yamashita, T AF Morozov, N Krusin-Elbaum, L Shibauchi, T Bulaevskii, LN Maley, MP Latyshev, YI Yamashita, T TI High-field quasiparticle tunneling in Bi2Sr2CaCu2O8+delta: Negative magnetoresistance in the superconducting state SO PHYSICAL REVIEW LETTERS LA English DT Article ID ZERO-TEMPERATURE LIMIT; T-C SUPERCONDUCTORS; AXIS RESISTIVITY; SINGLE-CRYSTALS; GAP; DISSIPATION; MECHANISM; PSEUDOGAP; INPLANE; VORTEX AB We report on the c-axis resistivity rho(c)(H) in Bi2Sr2CaCu2O8+delta that peaks in quasistatic magnetic fields up to 60 T. By suppressing the Josephson part of the two-channel (Cooper pair/quasiparticle) conductivity sigma(c)(H), we find that the negative slope of rho(c)(H) above the peak is due to quasiparticle tunneling conductivity a,(H) across the CuO2 layers below H-c2. At high fields (a) sigma(q),(H) grows linearly with H, and (b) rho(c)(T) tends to saturate (sigma(c) not equal 0) as T --> 0, consistent with the scattering at the nodes of the d-wave gap. A superlinear sigma(q)(H) marks the normal state above T-c. C1 Univ Calif Los Alamos Natl Lab, MST, STC, Los Alamos, NM 87545 USA. IBM Corp, Thomas J Watson Res Ctr, Yorktown Heights, NY 10598 USA. Tohoku Univ, RIEC, Aoba Ku, Sendai, Miyagi 9808577, Japan. Russian Acad Sci, Inst Radio Engn & Elect, Moscow 103907, Russia. RP Morozov, N (reprint author), Univ Calif Los Alamos Natl Lab, MST, STC, MS-K763, Los Alamos, NM 87545 USA. RI Shibauchi, Takasada/B-9349-2008 OI Shibauchi, Takasada/0000-0001-5831-4924 NR 25 TC 74 Z9 74 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD FEB 21 PY 2000 VL 84 IS 8 BP 1784 EP 1787 DI 10.1103/PhysRevLett.84.1784 PG 4 WC Physics, Multidisciplinary SC Physics GA 285HK UT WOS:000085383500037 ER PT J AU Kaminski, A Mesot, J Fretwell, H Campuzano, JC Norman, MR Randeria, M Ding, H Sato, T Takahashi, T Mochiku, T Kadowaki, K Hoechst, H AF Kaminski, A Mesot, J Fretwell, H Campuzano, JC Norman, MR Randeria, M Ding, H Sato, T Takahashi, T Mochiku, T Kadowaki, K Hoechst, H TI Quasiparticles in the superconducting state of Bi(2)Sr(2)CaCu(2)O(8+delta) SO PHYSICAL REVIEW LETTERS LA English DT Article ID ANGLE-RESOLVED PHOTOEMISSION; T-C SUPERCONDUCTORS; PHENOMENOLOGY AB Recent improvements in momentum resolution lead to qualitatively new angle-resolved photoemission spectroscopy results on the spectra of Bi(2)Sr(2)CaCu(2)O(8+delta) (Bi2212) along the (pi, pi) direction, where there is a node in the superconducting gap. We now see the intrinsic line shape, which indicates the presence of true quasiparticles at all Fermi momenta in the superconducting state, and lack thereof in the normal state. The region of momentum space probed here is relevant for charge transport, motivating a comparison of our results to conductivity measurements by infrared reflectivity. C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Boston Coll, Dept Phys, Chestnut Hill, MA 02467 USA. Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan. Natl Res Inst Met, Tsukuba, Ibaraki 305, Japan. Univ Tsukuba, Inst Mat Sci, Tsukuba, Ibaraki 305, Japan. Univ Wisconsin, Ctr Synchrotron Radiat, Stoughton, WI 53589 USA. RP Kaminski, A (reprint author), Univ Illinois, Dept Phys, Chicago, IL 60607 USA. RI Takahashi, Takashi/E-5080-2010; Sato, Takafumi/E-5094-2010; Tohoku, Arpes/A-4890-2010; Norman, Michael/C-3644-2013; OI Ding, Hong/0000-0003-4422-9248 NR 17 TC 159 Z9 162 U1 4 U2 11 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD FEB 21 PY 2000 VL 84 IS 8 BP 1788 EP 1791 DI 10.1103/PhysRevLett.84.1788 PG 4 WC Physics, Multidisciplinary SC Physics GA 285HK UT WOS:000085383500038 ER PT J AU Ortiz, G Harris, M Ballone, P AF Ortiz, G Harris, M Ballone, P TI Comment on "Zero temperature phases of the electron gas" - Ortiz et al. reply SO PHYSICAL REVIEW LETTERS LA English DT Article C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. Forschungszentrum, Inst Festkorperforsch, D-52425 Julich, Germany. Univ Messina, Ist Nazl Fis Mat, I-98166 Messina, Italy. RP Ortiz, G (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD FEB 21 PY 2000 VL 84 IS 8 BP 1843 EP 1843 DI 10.1103/PhysRevLett.84.1843 PG 1 WC Physics, Multidisciplinary SC Physics GA 285HK UT WOS:000085383500054 ER PT J AU Delahoy, AE Ruppert, A Contreras, M AF Delahoy, AE Ruppert, A Contreras, M TI Charging and discharging of defect states in CIGS/ZnO junctions SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT Symposium on Chalcogenide Semiconductors for Photovoltaics at the 1999 E-MRS Spring Conference CY JUN 01-04, 1999 CL STRASBOURG, FRANCE SP European Mat Res Soc DE CIGS; Cu(InGa)Se-x; zinc oxide; junctions; field; defects; metastability AB The formation of photovoltaic junctions in thin film CIGS has been explored through the deposition of ZnO directly onto the CIGS by the reaction of Zn and atomic oxygen. Most of these devices exhibit strong light soaking effects in which V-oc (at 1 sun) can increase from 250 mV to over 550 mV. A 12.3% efficient ZnO/CIGS solar cell was achieved. The soaking effect, which is the main topic of this paper, was found to be bias or field driven. Detailed investigations were conducted using a 'drive and interrogate' procedure, in which the device is driven between two steady states corresponding to two different voltage biases, with brief interrogation of V-oc at various times. Data spanning the temperature range 31-125 degrees C were acquired. It was found that the V-oc versus log(t) relaxation curves can be described by a stretched exponential. and scale with t.exp(-E/kT) as a parameter, yielding E = 0.51 eV. Junction capacitance data are also reported. The underlying process, whether electronic or ionic, possesses a wide range of time constants. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Energy Photovolta Inc, Princeton, NJ 08543 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Delahoy, AE (reprint author), Energy Photovolta Inc, POB 7456, Princeton, NJ 08543 USA. NR 6 TC 19 Z9 20 U1 2 U2 16 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD FEB 21 PY 2000 VL 361 BP 140 EP 144 DI 10.1016/S0040-6090(99)00787-7 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 286RA UT WOS:000085457900029 ER PT J AU Contreras, MA Egaas, B King, D Swartzlander, A Dullweber, T AF Contreras, MA Egaas, B King, D Swartzlander, A Dullweber, T TI Texture manipulation of CuInSe2 thin films SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT Symposium on Chalcogenide Semiconductors for Photovoltaics at the 1999 E-MRS Spring Conference CY JUN 01-04, 1999 CL STRASBOURG, FRANCE SP European Mat Res Soc DE texture; preferred orientation; CIS; CIGS; CuInSe2 AB We present a growth method that allows tailoring of preferred orientation in CuInSe2 thin-films grown on Mo-coated soda-lime glass substrates. In particular, films exhibiting a (204) preferred orientation are demonstrated, in addition to already reported(112) and randomly oriented Alms. Effects of substrate composition, growth temperature, and final film composition on texture phenomena are presented, In general, we find that texture is highly dependent on growth temperature, substrate material and, in the cast: of Mo-coated soda-lime glass substrates, the structural properties of the Mo layer. We provide evidence for the attainment of such structural orientation, and we present a growth model to explain the mechanism allowing such modifications. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Stuttgart, Inst Phys Elekt, D-70569 Stuttgart, Germany. RP Contreras, MA (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 10 TC 73 Z9 81 U1 0 U2 14 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD FEB 21 PY 2000 VL 361 BP 167 EP 171 DI 10.1016/S0040-6090(99)00778-6 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 286RA UT WOS:000085457900034 ER PT J AU Heske, C Eich, D Groh, U Fink, R Umbach, E van Buuren, T Bostedt, C Franco, N Terminello, LJ Grush, MM Callcott, TA Himpsel, FJ Ederer, DL Perera, RCC Riedl, W Karg, F AF Heske, C Eich, D Groh, U Fink, R Umbach, E van Buuren, T Bostedt, C Franco, N Terminello, LJ Grush, MM Callcott, TA Himpsel, FJ Ederer, DL Perera, RCC Riedl, W Karg, F TI Self-limitation of Na content at the CdS/Cu(In,Ga)Se-2 solar cell heterojunction SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT Symposium on Chalcogenide Semiconductors for Photovoltaics at the 1999 E-MRS Spring Conference CY JUN 01-04, 1999 CL STRASBOURG, FRANCE SP European Mat Res Soc DE CdS/Cu(In,Ga)Se-2; Na impurities; buried interfaces; impurity localization ID CU(IN,GA)SE-2 AB The localization of Na impurities at the buried heterojunction of CdS/Cu(In,Ga)Se: thin film solar cells has been studied by photoelectron spectroscopy and X-ray emission spectroscopy. This combination of a surface- and a bulk-sensitive technique allows to identify the localization of impurities at a buried interface in a non-destructive. semi-quantitative. and element-specific way. We compare samples with increasing CdS-overlayer thickness on (a a CIGS film with nominal Na content and (b) a Na-lich CIGS film. The data clearly indicate a self-limitation of the Na content at this interface. The consequences are discussed in view of the possibility to tailor the electronic structure of the buried heterojunction by controlling the nominal Na content in the CIGS film. (C) 2000 Elsevier science S.A. All rights reserved. C1 Univ Wurzburg, D-97074 Wurzburg, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Tennessee, Knoxville, TN 37996 USA. Univ Wisconsin, Dept Phys, Madison, WI USA. Tulane Univ, New Orleans, LA 70118 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Siemens AG, Corp Res & Dev, D-80807 Munich, Germany. Siemens Solar GMBH, D-80807 Munich, Germany. RP Heske, C (reprint author), Univ Wurzburg, D-97074 Wurzburg, Germany. RI Fink, Rainer/C-5333-2008; Fink, Rainer/F-8365-2010 OI Fink, Rainer/0000-0002-6896-4266; Fink, Rainer/0000-0002-6896-4266 NR 10 TC 5 Z9 5 U1 3 U2 14 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD FEB 21 PY 2000 VL 361 BP 360 EP 363 DI 10.1016/S0040-6090(99)00769-5 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 286RA UT WOS:000085457900070 ER PT J AU Bhattacharya, RN Hiltner, JF Batchelor, W Contreras, MA Noufi, RN Sites, JR AF Bhattacharya, RN Hiltner, JF Batchelor, W Contreras, MA Noufi, RN Sites, JR TI 15.4% CuIn(1-x)Ga(x)Se(2)-based photovoltaic cells from solution-based precursor films SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT Symposium on Chalcogenide Semiconductors for Photovoltaics at the 1999 E-MRS Spring Conference CY JUN 01-04, 1999 CL STRASBOURG, FRANCE SP European Mat Res Soc DE electrodeposition; electroless deposition; CuIn(1-x)Ga(x)Se(2); physical vapor deposition ID SOLAR-CELLS; DEVICE AB We have fabricated 15.4%- and 12.4%-efficient CuIn(1-x)Ga(x)Se(2) (CIGS)-based photovoltaic devices from solution-based electrodeposition (ED) and electroless-deposition (EL) precursors. As-deposited precursors are Cu-rich CIGS. Additional In. Ga, and Se are added to the ED and EL precursor films by physical vapor deposition (PVD) to adjust the final film composition to CuIn(1-x)Ga(x)Se(2). The ED and EL device parameters are compared with those of a recent world record, an 18.8%-efficient PVD device. The tools used for comparison are current voltage. capacitance voltage and spectral response characteristics. (C) 2000 Elsevier Science S.A. All lights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Colorado State Univ, Dept Phys, Ft Collins, CO 80523 USA. RP Bhattacharya, RN (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM raghu_bhattacharya@nrel.gov NR 8 TC 96 Z9 108 U1 4 U2 50 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD FEB 21 PY 2000 VL 361 BP 396 EP 399 DI 10.1016/S0040-6090(99)00809-3 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 286RA UT WOS:000085457900076 ER PT J AU Dullweber, T Hanna, G Shams-Kolahi, W Schwartzlander, A Contreras, MA Noufi, R Schock, HW AF Dullweber, T Hanna, G Shams-Kolahi, W Schwartzlander, A Contreras, MA Noufi, R Schock, HW TI Study of the effect of gallium grading in Cu(In,Ga)Se-2 SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT Symposium on Chalcogenide Semiconductors for Photovoltaics at the 1999 E-MRS Spring Conference CY JUN 01-04, 1999 CL STRASBOURG, FRANCE SP European Mat Res Soc DE bandgap grading; compositional grading high efficiency; CIGS; CuInGaSe2 ID CUINSE2; GAP AB Bandgap engineering in Cu(In,Ga)Se-2 (CIGS) based solar cells is an interesting tool to improve their. performance. We fabricate and analyse various kinds of gallium gradings in CIGS absorbers starting with different kinds of linear graded absorbers deposited by coevaporation. double graded absorbers by the three-stage process and finally multi graded absorbers by co-evaporation. Devices with linear grading show a strong influence of the slope of the grading on the open circuit voltage I:, and the short circuit current I,. The three-stage process employed for double graded profiles allows variations only in a limited range not suitable for systematic grading studies. Finally, the multi graded profiles combine the positive impacts of the linear graded devices. We found strong indications that it is possible to prepare a smaller bandgap to improve the current and a larger bandgap to improve the voltage in the same device by appropriate grading. The best devices show active area efficiencies up to eta = 16.7% and open circuit voltages up to V-oc = 691 mV at a minimum bandgap of E-g = 1.1 eV. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Univ Stuttgart, Inst Phys Elekt, D-70569 Stuttgart, Germany. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Dullweber, T (reprint author), Univ Stuttgart, Inst Phys Elekt, Pfaffenwaldring 47, D-70569 Stuttgart, Germany. NR 10 TC 72 Z9 79 U1 3 U2 42 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD FEB 21 PY 2000 VL 361 BP 478 EP 481 DI 10.1016/S0040-6090(99)00845-7 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 286RA UT WOS:000085457900093 ER PT J AU Farris, GM Newman, LS Frome, EL Shou, YL Barker, E Habbersett, RC Maier, L Smith, HN Marrone, BL AF Farris, GM Newman, LS Frome, EL Shou, YL Barker, E Habbersett, RC Maier, L Smith, HN Marrone, BL TI Detection of beryllium sensitivity using a flow cytometric lymphocyte proliferation test: the Immuno-Be-LPT SO TOXICOLOGY LA English DT Article DE beryllium; lymphocyte proliferation test; flow cytometry; autologous plasma; CD4; CD8; immunophenotyping; hypersensitivity; BrdU; DAPI; PI; tetanus; chronic beryllium disease ID TRANSFORMATION TEST; DIAGNOSTIC-VALUE; DNA CONTENT; DISEASE; CELLS; DERMATITIS; RESPONSES; ALLERGY AB Measurement of lymphocyte proliferation to detect hypersensitivity to beryllium (Be-LPT) in vitro is done presently using a method based on tritiated thymidine incorporation. Although this method is sensitive it gives no information on cell viability or responding lymphocyte subsets. We have developed reliable and simple flow cytometric assays for lymphocyte proliferation testing (Immuno-Be-LPT) by combining immunophenotyping with bromodeoxyuridine (BrdU) incorporation or DNA content using propidium iodide (PI) or 4'6'-diimidazolin-2-phenylindole (DAPI), Evaluation of beryllium-induced lymphocyte proliferation in blood cells from seven patients with chronic beryllium disease (CBD) and 120 beryllium workers by both the Be-LPT and the Immuno-Be-LPT showed agreement between the tests. The Immuno-Be-LPT provided additional information about the specific type of lymphocytes responding. CD4+ lymphocytes proliferated in response to beryllium in blood samples from all seven CBD individuals and CD8+ lymphocytes proliferated in six of the seven. Four beryllium workers without CBD had positive responses to beryllium primarily in the CD8+ cells. The use of the individual's own plasma supported a greater beryllium or tetanus-induced proliferation of CD4+ lymphocytes when compared to commercial human serum. The response of CD4+ lymphocytes measured in the Immuno-Be-LPT may provide a new marker for the diagnosis of CBD. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Cytometry Grp, BioSci Div, Los Alamos, NM 87545 USA. Natl Jewish Med & Res Ctr, Div Environm & Occupat Hlth Sci, Denver, CO 80206 USA. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. Univ Calif Los Alamos Natl Lab, Environm Safety & Hlth Div, Los Alamos, NM 87545 USA. RP Marrone, BL (reprint author), Univ Calif Los Alamos Natl Lab, Cytometry Grp, BioSci Div, M888,BS-5, Los Alamos, NM 87545 USA. RI Messier, Claude/A-2322-2008 OI Messier, Claude/0000-0002-4791-1763 FU NCRR NIH HHS [P41-RR013150] NR 25 TC 22 Z9 23 U1 0 U2 1 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0300-483X J9 TOXICOLOGY JI Toxicology PD FEB 21 PY 2000 VL 143 IS 2 BP 125 EP 140 DI 10.1016/S0300-483X(99)00167-5 PG 16 WC Pharmacology & Pharmacy; Toxicology SC Pharmacology & Pharmacy; Toxicology GA 291DK UT WOS:000085718700001 PM 10755700 ER PT J AU Bayramian, AJ Bibeau, C Schaffers, KI Marshall, CD Payne, SA AF Bayramian, AJ Bibeau, C Schaffers, KI Marshall, CD Payne, SA TI Gain saturation measurements of ytterbium-doped Sr-5(PO4)(3)F SO APPLIED OPTICS LA English DT Article ID S-FAP LASER; PERFORMANCE; CRYSTALS; ENERGY AB We report on the experimental measurement; of the saturated gain of Yb3+:Sr-5(PO4)(3)F at the 1047-nm laser line as a function of pump fluence and probe energy. The emission line was accurately modeled as a single homogeneous extraction, yielding values of 6.2 x 10(-20) cm(2) for the emission. cross section and 3.3 J/cm(2) for the saturation fluence. (C) 2000 Optical Society of America. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Bayramian, AJ (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave,L-482, Livermore, CA 94551 USA. EM bayramian1@llnl.gov NR 19 TC 7 Z9 7 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 FEB 20 PY 2000 VL 39 IS 6 BP 982 EP 985 DI 10.1364/AO.39.000982 PG 4 WC Optics SC Optics GA 285XC UT WOS:000085412800014 PM 18337976 ER PT J AU Pinto, PA Eastman, RG AF Pinto, PA Eastman, RG TI The physics of type Ia supernova light curves. I. Analytic results and time dependence SO ASTROPHYSICAL JOURNAL LA English DT Article DE diffusion; radiative transfer; stars : interiors; supernovae : general ID MODELS; EXPLOSIONS; NOVAE AB We develop an analytic solution of the radiation transport problem for Type Ia supernovae (SNe Ia) and show that it reproduces bolometric light curves produced by more detailed calculations under the assumption of a constant-extinction coefficient. This model is used to derive the thermal conditions in the interior of SNe Ia and to study the sensitivity of light curves to various properties of the underlying supernova explosions. Although the model is limited by simplifying assumptions, it is adequate for demonstrating that the relationship between SNe Ia maximum-light luminosity and rate of decline is most easily explained if SNe Ia span a range in mass. The analytic model is also used to examine the size of various terms in the transport equation under conditions appropriate to maximum light. For instance, the Eulerian and advective time derivatives are each shown to be of the same order of magnitude as other order vie terms in the transport equation. We conclude that a fully time-dependent solution to the transport problem is needed in order to compute SNe Ia light curves and spectra accurate enough to distinguish subtle differences of various explosion models. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Pinto, PA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 26 TC 91 Z9 91 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 FEB 20 PY 2000 VL 530 IS 2 BP 744 EP 756 DI 10.1086/308376 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500015 ER PT J AU Pinto, PA Eastman, RG AF Pinto, PA Eastman, RG TI The physics of type Ia supernova light curves. II. Opacity and diffusion SO ASTROPHYSICAL JOURNAL LA English DT Article DE distance scale; radiative transfer; supernovae : general ID ULTRAVIOLET OPACITY; RADIATIVE-TRANSFER; ENVELOPES; SPECTRA; MODELS AB We examine the nature of the opacity and radiation transport in Type Ia supernovae. The dominant opacity arises from line transitions. We discuss the nature of line opacities and diffusion in expanding media and the appropriateness of various mean and expansion opacities used in light-curve calculations. Fluorescence is shown to be the dominant physical process governing the rate at which energy escapes the supernova. We present a sample light curve that was obtained using a time-dependent solution of the radiative transport equation with a spectral resolution of 80 km s(-1) and employing an LTE equation of state. The result compares favorably with light curves and spectra of typical supernovae and is used to illustrate the physics controlling the evolution of the light curve and especially the secondary maxima seen in infrared photometry. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Pinto, PA (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM ppinto@as.arizona.edu; reastman@llnl.gov NR 30 TC 126 Z9 127 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2000 VL 530 IS 2 BP 757 EP 776 DI 10.1086/308380 PN 1 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500016 ER PT J AU Jernigan, JG Klein, RI Arons, J AF Jernigan, JG Klein, RI Arons, J TI Discovery of kilohertz fluctuations in Centaurus X-3: Evidence for photon bubble oscillations (PBO) and turbulence in a high-mass X-ray binary pulsar SO ASTROPHYSICAL JOURNAL LA English DT Article DE instabilities; stars : individual (Cen X-3, Cyg X-1); stars : neutron; stars : oscillations; turbulence ID MAGNETIZED NEUTRON STARS; ACCRETION; MODEL; MAGNETOSPHERE AB We report the discovery of kilohertz fluctuations, including quasiperiodic oscillations (QPO) at similar to 330 Hz (260-407 Hz) and similar to 760 Hz (671-849 Hz) and a broadband kilohertz continuum in the power-density spectrum of the high-mass X-ray binary pulsar Centaurus X-3. These observations of Cen X-3 were carried out with the Rossi X-Ray Timing Explorer (RXTE). The fluctuation spectrum is flat from millihertz to a few hertz, then steepens to f(-2) behavior between a few hertz and similar to 100 Hz. Above 100 Hz, the spectrum shows the QPO features, plus a flat continuum extending to similar to 1200 Hz and then falling out to similar to 1800 Hz. These results, which required the co-adding three days of observations of Cen X-3, are at least as fast as the fastest known variations in X-ray emission from an accreting compact object (kilohertz QPO in LMXB sources) and probably faster since extension to similar to 1800 Hz is indicated by the most likely parameterization of the data. Multidimensional radiation hydrodynamics simulations of optically thick plasma flow onto the magnetic poles of an accreting neutron star show that the fluctuations at frequencies above 100 Hz are consistent with photon bubble turbulence and oscillations (PBO) previously predicted to be observable in this source. We show that previous observations of Cen X-3 constrain the models to depend on only one parameter, the size of the polar cap. For a polar cap opening angle of 0.25 radians (polar cap radius similar to 2.5 km and area similar to 20 km(2), for a neutron star radius of 10 km), we show that the spectral form above 100 Hz is reproduced by the simulations, including the frequencies of the QPO and the relative power in the QPO and the kilohertz continuum. This has resulted in the first model-dependent measurement of the polar cap size of an X-ray pulsar. The simulations underpredict the overall amplitude of the observed spectrum, which we suggest is the consequence of a two-dimensional axisymmetric simulation of an intrinsically three-dimensional phenomenon. The power-density spectrum of Cen X-3 shows a dramatic decrease above similar to 1000 Hz, which suggests an optical depth similar to 30 across the accretion mound consistent with effects of radiative diffusion in the simulations. We identify this decline at high frequency as the first direct evidence of radiative diffusion near the surface of a neutron star (NS). We suggest the fluctuations observed at frequencies below 100 Hz, whose spectrum has a different form from that of the kilohertz phenomena, reflect intermittency in the mass transfer mechanism that carries plasma from the accretion disk to field aligned flow onto the neutron star's polar caps. Using simple estimates based on Rayleigh-Taylor instabilities, possibly modulated by intrinsic disk turbulence, we show that mass transfer in "blobs" forming through Rayleigh-Taylor disruption of the disk's inner edge can explain the large amplitude fluctuations required by the spectrum at frequencies f similar to 1 Hz, but only if magnetic pressure in the disk's innermost regions inflates the disk until its scale height is comparable to the magnetosphere's size similar to 4300 km. The observational results required the development of a procedure for the careful determination of the dead-time effects of the PCA. This procedure is described in Appendix A. As a consequence of the use of observations of Cyg X-1 for the estimation of dead-time corrections for the observations of Cen X-3, we have also demonstrated that the black hole Cyg X-l shows clear evidence of variability up to a frequency of similar to 280 Hz. Also observations of GX 17 + 2 were used to validate the procedure for dead-time corrections. This analysis of GX 17 + 2 clearly indicates the presence of a kilohertz QPO and the absence of any significant simultaneous kilohertz continuum. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Theoret Astrophys Ctr, Berkeley, CA 94720 USA. RP Jernigan, JG (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. EM jgj@xnet.ssl.berkeley.edu; klein@radhydro.berkeley.edu; arons@astroplasma.berkeley.edu NR 38 TC 26 Z9 26 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2000 VL 530 IS 2 BP 875 EP 889 DI 10.1086/308390 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500025 ER PT J AU Revnivtsev, MG Borozdin, KN Priedhorsky, WC Vikhlinin, A AF Revnivtsev, MG Borozdin, KN Priedhorsky, WC Vikhlinin, A TI Rossi X-Ray Timing Explorer observations of an outburst of recurrent X-ray nova GS 1354-644 SO ASTROPHYSICAL JOURNAL LA English DT Article DE novae, cataclysmic variables; stars : individual (GS 1354-644); X-rays : stars ID BLACK-HOLE CANDIDATES; RXTE OBSERVATION; HIGH STATE; RADIATION; COMPTONIZATION; VARIABILITY; CYGNUS-X-1; MODEL; REFLECTION; 4U-1608-52 AB We present the results of Rossi X-Ray Timing Explorer (RXTE) observations of GS 1354-644 during a modest outburst in 1997-1998. The source is one of a handful of black hole X-ray transients that are confirmed to be recurrent in X-rays. A 1987 outburst of the same source observed by Ginga was much brighter and showed a high/soft spectral state. In contrast, the 1997-1998 outburst showed a low/hard spectral state. Both states are typical of black hole binaries. The RXTE All-Sky Monitor observed an outburst duration of 150-200 days. PCA and HEXTE observations covered similar to 70 days near the maximum of the light curve and during the flux decline. Throughout the observations, the spectrum can be approximated by Compton upscattering of soft photons by energetic electrons. The hot electron cloud has a temperature kT similar to 30 keV and optical depth tau similar to 4-5. To fit the data well, an additional iron fluorescent line and reflection component are required, which indicates the presence of optically thick cool material, most probably in the outer part of the accretion disk. Dramatic fast variability was observed and has been analyzed in the context of a shot noise model. The spectrum appeared to be softest at the peaks of the shot noise variability. The shape of the power spectrum was typical for black hole systems in a low/hard state. We note a qualitative difference in the shape of the dependence of fractional variability on energy when we compare systems with black holes and with neutron stars. Since it is difficult to discriminate these systems on spectral grounds, at least in their low/hard states, this new difference might be important. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Revnivtsev, MG (reprint author), Russian Acad Sci, Inst Space Res, 84-32 Profsojuznaya Str,GSP 7, Moscow 117810, Russia. OI Priedhorsky, William/0000-0003-0295-9138 NR 57 TC 20 Z9 21 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2000 VL 530 IS 2 BP 955 EP 965 DI 10.1086/308386 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500033 ER PT J AU Lentz, EJ Baron, E Branch, D Hauschildt, PH Nugent, PE AF Lentz, EJ Baron, E Branch, D Hauschildt, PH Nugent, PE TI Metallicity effects in non-LTE model atmospheres of Type Ia supernovae SO ASTROPHYSICAL JOURNAL LA English DT Article DE line : formation; nuclear reactions, nucleosynthesis, abundances radiative transfer; stars : atmospheres; supernovae : general ID WHITE-DWARF MODELS; LIGHT CURVES; NUCLEOSYNTHESIS; CONSTANT; SPECTRA; LAMBDA AB We have calculated a grid of photospheric phase atmospheres of Type Ia supernovae (SNe Ia) with metallicities from 10 times to 1/30 the solar metallicity in the C+O layer of the deflagration model, W7. We have modeled the spectra using the multipurpose non-LTE model atmosphere and spectrum synthesis code PHOENIX. We show models for the epochs 7, 10, 15, 20, and 35 days after explosion. When compared to observed spectra obtained at the approximately corresponding epochs, these synthetic spectra fit reasonably well. The spectra show variation in the overall level of the UV continuum with lower fluxes for models with higher metallicity in the unburned C+O layer. This is consistent with the classical surface cooling and line-blocking effect due to metals in the outer layers of C+O. The UV features also move consistently to the blue with higher metallicity, demonstrating that they are forming at shallower and faster layers in the atmosphere. The potentially most useful effect is the blueward movement of the Si II feature at 6150 Angstrom with increasing C+O layer metallicity. We also demonstrate the more complex effects of metallicity variations by modifying the (54)Fe content of the incomplete burning zone in W7 at maximum light. We briefly address some shortcomings of the W7 model when compared to observations. Finally, we identify that the split in the Ca H+K feature produced in W7 and observed in some SNe Ia is due to a blending effect of Ca II and Si II and does not necessarily represent a complex abundance or ionization effect in Ca II. C1 Univ Oklahoma, Dept Phys & Astron, Norman, OK 73019 USA. Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. Univ Georgia, Ctr Simulat Phys, Athens, GA 30602 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Lentz, EJ (reprint author), Univ Oklahoma, Dept Phys & Astron, 440 W Brooks, Norman, OK 73019 USA. EM lentz@mail.nhn.ou.edu; baron@mail.nhn.ou.edu; branch@mail.nhn.ou.edu; yeti@hal.physast.uga.edu; penugent@lbl.gov RI Baron, Edward/A-9041-2009; Lentz, Eric/M-7173-2015 OI Baron, Edward/0000-0001-5393-1608; Lentz, Eric/0000-0002-5231-0532 NR 35 TC 116 Z9 116 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2000 VL 530 IS 2 BP 966 EP 976 DI 10.1086/308400 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500034 ER PT J AU Dohrmann, CR Key, SW Heinstein, MW AF Dohrmann, CR Key, SW Heinstein, MW TI Methods for connecting dissimilar three-dimensional finite element meshes SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE finite elements; dissimilar meshes; uniform strain; constraint equations AB Two methods are presented for connecting dissimilar three-dimensional finite element meshes. The first method combines the concept of master and slave surfaces with the uniform strain approach for finite elements. By modifying the boundaries of elements on a slave surface, corrections are made to element formulations such that first-order patch tests are passed. The second method is based entirely on constraint equations, but only passes a weaker form of the patch test for non-planar surfaces. Both methods can be used to connect meshes with different element types. In addition, master and slave surfaces can be designated independently of relative mesh resolutions. Example problems in three-dimensional linear elasticity are presented. Published in 2000 by 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, POB 5800,Mail Stop 0847, Albuquerque, NM 87185 USA. NR 14 TC 45 Z9 45 U1 1 U2 4 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 FEB 20 PY 2000 VL 47 IS 5 BP 1057 EP 1080 DI 10.1002/(SICI)1097-0207(20000220)47:5<1057::AID-NME821>3.3.CO;2-7 PG 24 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 279NA UT WOS:000085049900007 ER PT J AU Randler, RJ Kolb, DM Ocko, BM Robinson, IK AF Randler, RJ Kolb, DM Ocko, BM Robinson, IK TI Electrochemical copper deposition on Au(100): a combined in situ STM and in situ surface X-ray diffraction study SO SURFACE SCIENCE LA English DT Article DE alloys; copper; electrochemical methods; epitaxy; gold; metal-metal interfaces; scanning tunneling microscopy; single crystal surfaces; X-ray scattering, diffraction, and reflection ID AU(001) SURFACE; INITIAL-STAGES; CU; GROWTH; FILMS; ELECTRODEPOSITION; INTERFACES; SCATTERING; TRANSITION; PHASES AB The electrochemical deposition of copper onto Au(100) has been investigated using in situ scanning tunneling microscopy (STM) and in situ surface X-ray scattering (SXS). Copper deposition from sulfuric acid solutions starts at potentials positive of the reversible Nernst potential, where a pseudomorphic (1x1) copper monolayer forms. Negative of the Nernst potential, STM measurements have revealed that bulk copper nucleates at the surface defects, step edges or island rims of the gold substrate. A bilayer of copper is formed on top of the underlying copper monolayer and further growth proceeds in a layer-by-layer fashion. Atomic resolution STM images have shown that the copper film has a pseudomorphic structure for films less than or equal to 10 layers. Surface X-ray scattering measurements have confirmed the pseudomorphic arrangement and have provided a precise measure of the copper layer spacing (1.45+/-0.02 Angstrom), in good agreement with the value obtained from the copper-copper step height in the STM measurements. This layer spacing is much smaller than the value expected for fee copper. The combined structural analysis leads to the conclusion of a thermodynamically stable bcc-like structure. Both the X-ray and STM results suggest alloying at the copper-gold interface. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Ulm, Abt Elektrochem, D-89069 Ulm, Germany. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. RP Kolb, DM (reprint author), Univ Ulm, Abt Elektrochem, D-89069 Ulm, Germany. NR 33 TC 49 Z9 50 U1 0 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD FEB 20 PY 2000 VL 447 IS 1-3 BP 187 EP 200 DI 10.1016/S0039-6028(99)01170-X PG 14 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 289JA UT WOS:000085615700026 ER PT J AU Herman, GS Gao, Y Tran, TT Osterwalder, J AF Herman, GS Gao, Y Tran, TT Osterwalder, J TI X-ray photoelectron diffraction study of an anatase thin film: TiO2(001) SO SURFACE SCIENCE LA English DT Article DE anatase; polycrystalline thin films; titanium; titanium oxide; X-ray photoelectron spectroscopy ID SINGLE-CRYSTAL ANATASE; ELECTRON-DIFFRACTION; OPTICAL-PROPERTIES; SURFACE-STRUCTURE; RUTILE TIO2; SPECTROSCOPY; TIO2(110); TITANIUM; WATER; OXIDE AB An anatase thin film, TiO2(001), has been grown by metal-organic chemical vapor deposition on a SrTiO3(001) substrate. The electronic and structural properties of the anatase thin film were investigated by X-ray photoelectron spectroscopy, low energy electron diffraction (LEED), and X-ray photoelectron diffraction (XPD). Comparisons of the core-level binding energies for O 1s and Ti 2p(3/2) photoelectrons was made between anatase and rutile, and were found to be identical for both polymorphs. Structurally, the surface gave a (1x1) LEED pattern with a high background, indicating regions of good long-range order. Comparison between experimental XPD data and single-scattering cluster calculations indicate that there is good agreement with an anatase crystal termination, and poor agreement with a rutile crystal termination. Furthermore, good agreement was found at low takeoff angles for experiment and calculations suggesting that the thin film has good short-range order at the surface. This study indicates that anatase is stable and does not undergo a transformation to the rutile polymorph when exposed to atmosphere after film growth or after heating to low temperatures in ultrahigh vacuum. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Zurich, Inst Phys, CH-8057 Zurich, Switzerland. RP Herman, GS (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999,MS K8-93, Richland, WA 99352 USA. NR 52 TC 70 Z9 70 U1 3 U2 28 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD FEB 20 PY 2000 VL 447 IS 1-3 BP 201 EP 211 DI 10.1016/S0039-6028(99)01186-3 PG 11 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 289JA UT WOS:000085615700027 ER PT J AU Zajonz, H Gibbs, D Baddorf, AP Jahns, V Zehner, DM AF Zajonz, H Gibbs, D Baddorf, AP Jahns, V Zehner, DM TI Structure and growth of strained Cu films on Ru(0001) SO SURFACE SCIENCE LA English DT Letter DE copper; epitaxy; ruthenium; surface stress; surface structure, morphology, roughness, and topography; X-ray scattering, diffraction, and reflection ID RAY-SCATTERING MEASUREMENTS; METAL-METAL INTERFACES; SURFACE; CU/RU(0001); RELAXATION; PHASES AB We present X-ray scattering studies of the structure and growth of the heteroepitaxial interface Cu-Ru(0001) between 300 and 870 K. For Cu depositions of between one and two monolayers (ML), a bilayer stripe-phase coexists with domains pseudomorphic to the Ru substrate. At the completion of 2 ML, the stripe-phase wavevector abruptly locks to that of the substrate with a commensurability delta=1/16 or 1/18, depending on the temperature. Above 2 ML, a cooperative growth process leads to three-phase coexistence, including the bilayer stripe-phase and rotated and unrotated bulk-like Cu islands. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Zajonz, H (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Baddorf, Arthur/I-1308-2016 OI Baddorf, Arthur/0000-0001-7023-2382 NR 21 TC 16 Z9 16 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD FEB 20 PY 2000 VL 447 IS 1-3 BP L141 EP L146 DI 10.1016/S0039-6028(99)01222-4 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 289JA UT WOS:000085615700001 ER PT J AU Lurie, IS Bailey, CG Anex, DS Bethea, MJ McKibben, TD Casale, JF AF Lurie, IS Bailey, CG Anex, DS Bethea, MJ McKibben, TD Casale, JF TI Profiling of impurities in illicit methamphetamine by high-performance liquid chromatography and capillary electrochromatography SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 23rd International Symposium on High Performance Liquid Phase Separations and Related Techniques CY MAY 30-JUN 04, 1999 CL GRANADA, SPAIN DE forensic analysis; methamphetamine ID HYDRIODIC ACID; RED PHOSPHORUS; ELECTROPHORESIS; AMPHETAMINE; SEPARATION; EPHEDRINE; REDUCTION AB High performance liquid chromatography (HPLC) with photodiode array (PDA) UV and fluorescence (FL) detection, and capillary electrochromatography (CEC) with laser-induced fluorescence (LIF) detection were investigated for the analysis of acidic extracts derived from illicit methamphetamine. These compounds include major impurities from the hydriodic acid/red phosphorous reduction method, i.e., 1,3-dimethyl-2-phenylnaphthalene and 1-benzyl-3-methylnaphthalene, and other trace-level, structurally related impurities. For certain of these solutes, HPLC with conventional FL detection gave at least a 60x increase in sensitivity over UV detection. In addition, other highly fluorescent impurities were detected in methamphetamine produced via four other synthetic routes. The use of a rapid scanning FL detector (with acquisition of "on the fly" excitation or emission) provided structural information and gave "optimum" excitation and emission detection wavelengths. CEC with LIF detection using UV laser excitation provided greatly improved chromatography over HPLC, with good detection limits in the low ng/ml range. Both methodologies provide good run-to-run repeatability, and have the capability to distinguish between samples. (C) 2000 Published by Elsevier Science B.V. C1 US Drug Enforcement Adm, Special Testing & Res Lab, Mclean, VA 22102 USA. Sandia Natl Labs, Chem & Radiat Detect Lab, Livermore, CA 94551 USA. RP Lurie, IS (reprint author), US Drug Enforcement Adm, Special Testing & Res Lab, 7704 Old Springhouse Rd, Mclean, VA 22102 USA. OI Lurie, Ira/0000-0003-3844-5120 NR 22 TC 33 Z9 36 U1 1 U2 5 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 FEB 18 PY 2000 VL 870 IS 1-2 BP 53 EP 68 DI 10.1016/S0021-9673(99)00849-3 PG 16 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 286QD UT WOS:000085455900008 PM 10722062 ER PT J AU Schiffer, WK Gerasimov, MR Bermel, RA Brodie, JD Dewey, SL AF Schiffer, WK Gerasimov, MR Bermel, RA Brodie, JD Dewey, SL TI Stereoselective inhibition of dopaminergic activity by gamma vinyl-GABA following a nicotine or cocaine challenge: A PET/microdialysis study SO LIFE SCIENCES LA English DT Article DE gamma vinyl-GABA; enantiomers; positron emission tomography; microdialysis; nicotine; cocaine ID VIGABATRIN; RACLOPRIDE; BINDING; PET AB Elevation of endogenous GABA by the racemic mixture of gamma vinyl-GABA (GVG, Vigabatrin(R)) decreases extracellular nucleus accumbens (NAc) dopamine (DA) levels and diminishes the response to many drugs of abuse known to elevate DA in the mesocorticolimbic system. We investigated the effects of the individual enantiomers (S(+)GVG, R(-)-GVG) on cocaine-induced NAc DA in rodents as well as the effects of nicotine-induced increases in primates. In a series of microdialysis experiments in freely moving animals, S(+)-GVG (150 mg/kg), R(-)-GVG (150 mg/kg) or racemic (R, S) GVG (300 mg/kg) was administered 2.5 hours prior to cocaine (20 mg/kg) administration. When compared with cocaine alone, the R(-) enantiomer did not significantly inhibit cocaine induced NAc DA release. S(+)-GVG, at half the dose of the racemic mixture (150 mg/kg), inhibited cocaine-induced DA elevation by 40%, while the racemic mixture (300 mg/kg) inhibited cocaine-induced DA release by 31.%. In addition, our PET studies in primates demonstrated that S(+)GVG completely inhibits nicotine-induced increases in the corpus striatum, again at half the dose of the racemic mixture. The R(-) enantiomer was ineffective. Although the S(+) enantiomer has been well established as the active compound in the treatment of epilepsy, the efficacy of this enantiomer with regard to mesolimbic DA inhibition generates a complex series of clinical and neurochemical issues. Further investigations will determine the locus of action and physiologic properties of each enantiomer. (C) 2000 Elsevier Science Inc. C1 NYU, Sch Med, Dept Psychiat, New York, NY 10012 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Schiffer, WK (reprint author), NYU, Sch Med, Dept Psychiat, New York, NY 10012 USA. FU NIMH NIH HHS [MH49165]; PHS HHS [R2955155] NR 11 TC 14 Z9 15 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0024-3205 J9 LIFE SCI JI Life Sci. PD FEB 18 PY 2000 VL 66 IS 13 BP PL169 EP PL173 DI 10.1016/S0024-3205(00)00432-X PG 5 WC Medicine, Research & Experimental; Pharmacology & Pharmacy SC Research & Experimental Medicine; Pharmacology & Pharmacy GA 286EA UT WOS:000085429600012 PM 10737423 ER PT J AU Spengler, SJ AF Spengler, SJ TI Computers and biology - Bioinformatics in the information age SO SCIENCE LA English DT Editorial Material C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Bioinformat & Computat Genom, Berkeley, CA 94720 USA. RP Spengler, SJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Bioinformat & Computat Genom, LBNL 84-171,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 6 TC 19 Z9 20 U1 0 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 FEB 18 PY 2000 VL 287 IS 5456 BP 1221 EP + DI 10.1126/science.287.5456.1221 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 286KG UT WOS:000085444700038 PM 10712158 ER PT J AU Santer, BD Wigley, TML Gaffen, DJ Bengtsson, L Doutriaux, C Boyle, JS Esch, M Hnilo, JJ Jones, PD Meehl, GA Roeckner, E Taylor, KE Wehner, MF AF Santer, BD Wigley, TML Gaffen, DJ Bengtsson, L Doutriaux, C Boyle, JS Esch, M Hnilo, JJ Jones, PD Meehl, GA Roeckner, E Taylor, KE Wehner, MF TI Interpreting differential temperature trends at the surface and in the lower troposphere SO SCIENCE LA English DT Article ID AIR-TEMPERATURE; CLIMATE-CHANGE; TIME-SERIES; SATELLITE; REANALYSIS; RECORDS; AEROSOL AB Estimated global-scale temperature trends at Earth's surface (as recorded by thermometers) and in the Lower troposphere (as monitored by satellites) diverge by up to 0.14 degrees C per decade over the period 1979 to 1998. Accounting for differences in the spatial coverage of satellite and surface measurements reduces this differential, but still Leaves a statistically significant residual of roughly 0.1 degrees C per decade. Natural internal climate variability alone, as simulated in three state-of-the-art coupled atmosphere-ocean models, cannot completely explain this residual trend difference. A model forced by a combination of anthropogenic factors and volcanic aerosols yields surface-troposphere temperature trend differences closest to those observed. C1 Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Livermore, CA 94550 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. NOAA, Air Resources Lab, Silver Spring, MD 20910 USA. Max Planck Inst Meteorol, D-20146 Hamburg, Germany. Univ E Anglia, Climat Res Unit, Norwich NR4 7TJ, Norfolk, England. RP Santer, BD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Livermore, CA 94550 USA. RI Wigley, Tom/B-4705-2008; Jones, Philip/C-8718-2009; Taylor, Karl/F-7290-2011; Santer, Benjamin/F-9781-2011 OI Jones, Philip/0000-0001-5032-5493; Taylor, Karl/0000-0002-6491-2135; NR 49 TC 67 Z9 72 U1 2 U2 11 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 FEB 18 PY 2000 VL 287 IS 5456 BP 1227 EP 1232 DI 10.1126/science.287.5456.1227 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 286KG UT WOS:000085444700040 ER PT J AU Gaffen, DJ Santer, BD Boyle, JS Christy, JR Graham, NE Ross, RJ AF Gaffen, DJ Santer, BD Boyle, JS Christy, JR Graham, NE Ross, RJ TI Multidecadal changes in the vertical temperature structure of the tropical troposphere SO SCIENCE LA English DT Article ID SURFACE-TEMPERATURE; SATELLITE; TRENDS; RECORDS; CARDS AB Trends in global lower tropospheric temperature derived from satellite observations since 1979 show Less warming than trends based on surface meteorological observations. Independent radiosonde observations of surface and tropospheric temperatures confirm that, since 1979, there has been greater warming at the surface than aloft in the tropics. Associated lapse-rate changes show a decrease in the static stability of the atmosphere, which exceeds unforced static stability variations in climate simulations with state-of-the-art coupled ocean-atmosphere models, The differential temperature trends and Lapse-rate changes seen during the satellite era are not sustained back to 1960. C1 NOAA, Air Resources Lab, RARL, Silver Spring, MD 20910 USA. Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diagnost & Intercomparison, Livermore, CA 94550 USA. Univ Alabama, Earth Syst Sci Lab, Huntsville, AL 35899 USA. Univ Calif San Diego, Scripps Inst Oceanog, Div Climate Res, La Jolla, CA 92093 USA. RP Gaffen, DJ (reprint author), NOAA, Air Resources Lab, RARL, 1315 East West Highway, Silver Spring, MD 20910 USA. RI Santer, Benjamin/F-9781-2011 NR 33 TC 77 Z9 78 U1 1 U2 11 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 FEB 18 PY 2000 VL 287 IS 5456 BP 1242 EP 1245 DI 10.1126/science.287.5456.1242 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 286KG UT WOS:000085444700043 ER PT J AU Baskaran, S Liu, J Domansky, K Kohler, N Li, XH Coyle, C Fryxell, GE Thevuthasan, S Williford, RE AF Baskaran, S Liu, J Domansky, K Kohler, N Li, XH Coyle, C Fryxell, GE Thevuthasan, S Williford, RE TI Low dielectric constant mesoporous silica films through molecularly templated synthesis SO ADVANCED MATERIALS LA English DT Article ID LOW-DENSITY XEROGELS; LOW-K-DIELECTRICS; AMBIENT-PRESSURE C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Baskaran, S (reprint author), Pacific NW Natl Lab, Mail Stop K2-44,POB 999, Richland, WA 99352 USA. NR 20 TC 221 Z9 227 U1 3 U2 33 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA POSTFACH 101161, 69451 WEINHEIM, GERMANY SN 0935-9648 EI 1521-4095 J9 ADV MATER JI Adv. Mater. PD FEB 17 PY 2000 VL 12 IS 4 BP 291 EP 294 DI 10.1002/(SICI)1521-4095(200002)12:4<291::AID-ADMA291>3.3.CO;2-G PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 285QT UT WOS:000085400300011 ER PT J AU Magnussen, OM Scherer, J Ocko, BM Behm, RJ AF Magnussen, OM Scherer, J Ocko, BM Behm, RJ TI In situ X-ray scattering study of the passive film on Ni(111) in sulfuric acid solution SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SCANNING-TUNNELING-MICROSCOPY; OXIDE-FILMS; IN-SITU; NICKEL; DIFFRACTION; REFLECTIVITY; ELECTROLYTE; NI(100); XPS AB Results of an in situ X-ray scattering study of the passive film formed on Ni(111) electrodes by passivation in 0.05 M H2SO4 (pH 1.0) at 0.50 V-Ag/AgCl are reported and compared with results on the film formed by oxidation in air at room temperature. Tn both cases, ultrathin, (111)-oriented NiO films are observed, which are aligned with the Ni substrate lattice and slightly expanded along the surface normal with respect to bulk NiO. However, two major structural differences are found: (i) while on the air-formed oxide parallel (NiO[1 (1) over bar 0] \\ Ni[1 (1) over bar 0]) and antiparallel (NiO[1 (1) over bar 0] \\ Ni[(1) over bar 10]) oriented domains coexist; the passive film exhibits. a well-defined antiparallel orientation and (ii) the lattice of the passive film is, in contrast to that of the air-fomed oxide, tilted relative to the substrate with a broad angular dispersion of the tilt angle centered at about 3.3 degrees. C1 Univ Ulm, Abt Oberflachenchem & Katalyse, D-89069 Ulm, Germany. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Magnussen, OM (reprint author), Univ Ulm, Abt Oberflachenchem & Katalyse, D-89069 Ulm, Germany. NR 25 TC 52 Z9 52 U1 0 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD FEB 17 PY 2000 VL 104 IS 6 BP 1222 EP 1226 DI 10.1021/jp993615v PG 5 WC Chemistry, Physical SC Chemistry GA 285MY UT WOS:000085393900012 ER PT J AU Chen, KD Bell, AT Iglesia, E AF Chen, KD Bell, AT Iglesia, E TI Kinetics and mechanism of oxidative dehydrogenation of propane on vanadium, molybdenum, and tungsten oxides SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID CATALYTIC PROPERTIES; SELECTIVE OXIDATION; BUTANE OXIDATION; OXYDEHYDROGENATION; ALKANES; MOLYBDATE; ZIRCONIA; STYRENE AB The effect of cation identity on oxidative dehydrogenation (ODH) pathways was examined using two-dimensional VOx, MoOx, and WOx structures supported on ZrO2. The similar kinetic rate expressions obtained on MoOx and VOx catalysts confirmed that oxidative dehydrogenation of propane occurs via similar pathways, which involve rate-determining C-H bond activation steps using lattice oxygen atoms. The activation energies for propane dehydrogenation and for propene combustion increase iri the sequence VOx/ZrO2 < MoOx/ZrO2 < WOx/ZrO2 the corresponding reaction rates decrease in this sequence, suggesting that turnover rates reflect C-EI bond cleavage activation energies, which are in turn influenced by the reducibility of these metal oxides. Propane ODH activation energies are higher than for propene combustion. This leads to an increase in maximum alkene yields and in the ratio of rate constants for propane ODH and propene combustion as temperature increases. This difference in activation energy (48-61 kJ/mol) between propane ODH and propene combustion is larger than between bond dissociation enthalpies for the weakest C-H bond in propane and propene (40 kJ/mol) and it increases in the sequence VOx/ZrO2 < MoOx/ZrO2 < WOx/ZrO2 suggest that relative propane ODH and propene combustion rates depend not only on C-H bond energy differences but also on the adsorption enthalpies for propene and propane, which reflect the Lewis acidity of cations involved in Jr bonding of alkenes On Oxide surfaces.. The observed difference in activation energies between propane ODH and propane combustion increases as the Lewis acidity of the cations increases (V5+ < Mo6+ < W6+). C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat & Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Bell, AT (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat & Chem Sci, Berkeley, CA 94720 USA. RI Iglesia, Enrique/D-9551-2017; OI Iglesia, Enrique/0000-0003-4109-1001; Bell, Alexis/0000-0002-5738-4645 NR 49 TC 160 Z9 161 U1 13 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 FEB 17 PY 2000 VL 104 IS 6 BP 1292 EP 1299 DI 10.1021/jp9933875 PG 8 WC Chemistry, Physical SC Chemistry GA 285MY UT WOS:000085393900022 ER PT J AU Segalman, DJ Fulcher, CWG Reese, GM Field, RV AF Segalman, DJ Fulcher, CWG Reese, GM Field, RV TI An efficient method for calculating r.m.s. von Mises stress in a random vibration environment SO JOURNAL OF SOUND AND VIBRATION LA English DT Article AB A rigorous and efficient method is presented for calculation of root-mean-square (r.m.s.) von Mises stresses for linear structures excited by stationary random loads. The r.m.s, value is expressed in terms of the zero time-lag covariance matrix of the loads, which in most applications of structural analysis will be calculated from frequency-domain, stress-component transfer functions and the cross-spectral density matrix of the applied loads. The key relation presented is one suggested in past literature, but that does not appear to have been exploited previously in this manner. The exact determination of r.m.s. von Mises stress is used to demonstrate that the Miles relation, commonly used in design, can be conservative or non-conservative. Finally, because of the efficiency with which the exact r.m.s. von Mises stress can be calculated, the analyst can now perform surveys on von Mises stresses routinely, allowing a thorough investigation into the reliability of an engineering design. (C) 2000 Academic Press. C1 Sandia Natl Labs, Struct Dynam & Vibrat Control Dept, Albuquerque, NM 87185 USA. RP Segalman, DJ (reprint author), Sandia Natl Labs, Struct Dynam & Vibrat Control Dept, POB 5800,Mail Stop 0847, Albuquerque, NM 87185 USA. RI Field, Richard/K-6468-2013 OI Field, Richard/0000-0002-2765-7032 NR 13 TC 9 Z9 9 U1 0 U2 3 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD FEB 17 PY 2000 VL 230 IS 2 BP 393 EP 410 DI 10.1006/jsvi.1999.2606 PG 18 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 286GK UT WOS:000085435100011 ER PT J AU Balatsky, AV AF Balatsky, AV TI Superconductivity - From obscurity to impurity SO NATURE LA English DT Editorial Material ID MAGNETIC-IMPURITIES C1 Univ Calif Los Alamos Natl Lab, Div Theory, Los Alamos, NM 87545 USA. RP Balatsky, AV (reprint author), Univ Calif Los Alamos Natl Lab, Div Theory, MS B 262, Los Alamos, NM 87545 USA. NR 9 TC 21 Z9 21 U1 1 U2 2 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD FEB 17 PY 2000 VL 403 IS 6771 BP 717 EP 718 DI 10.1038/35001703 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 286BE UT WOS:000085423100033 ER PT J AU Grossman, Y Neubert, M AF Grossman, Y Neubert, M TI Neutrino masses and mixings in non-factorizable geometry SO PHYSICS LETTERS B LA English DT Article DE field theories in higher dimensions; neutrino physics; beyond standard model ID OSCILLATIONS; MATTER; FLUX; SPECTROSCOPY; DIMENSIONS; MILLIMETER; FERMIONS AB We study bulk fermion fields in the localized gravity model with non-factorizable metric recently proposed by Randall and Sundrum, and Gogberashvili. In addition to a tower of weak-scale Kaluza-Klein states we find a zero mode for any value of the fundamental fermion mass. If the fermion mass is larger than half the curvature of the compact dimension, the zero mode can be localized on the "hidden" 3-brane in the Randall-Sundrum model. Identifying this mode with a right-handed neutrino provides a new way for obtaining small Dirac neutrino masses without invoking a see-saw mechanism, Cancellation of the parity anomaly requires introducing an even number of bulk fermions. This naturally leads to a strong hierarchy of neutrino masses and generically large mixing angles. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Cornell Univ, Newman Lab Nucl Studies, Ithaca, NY 14853 USA. RP Grossman, Y (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 67 TC 613 Z9 613 U1 1 U2 9 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 FEB 17 PY 2000 VL 474 IS 3-4 BP 361 EP 371 DI 10.1016/S0370-2693(00)00054-X PG 11 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 288MQ UT WOS:000085567100018 ER EF