FN Thomson Reuters Web of Science™ VR 1.0 PT S AU Lee, J Tierney, B Johnston, W AF Lee, J Tierney, B Johnston, W BE Sloot, P Bubak, M Hoekstra, A Hertzberger, B TI Data intensive distributed computing: A medical application example SO HIGH-PERFORMANCE COMPUTING AND NETWORKING, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 7th International Conference and Exhibition on High-Performance Computing and Networking (HPCN EUROPE 99) CY APR 12-14, 1999 CL AMSTERDAM, NETHERLANDS SP Dutch HPCN Fdn, Dutch Org Sci Res, Univ Amsterdam AB Modem scientific computing involves organizing, moving, visualizing, and analyzing massive amounts of data from around the world, as well as employing large-scale computation. The distributed systems that solve large-scale problems will always involve aggregating and scheduling many resources. Data must be located and staged, cache and network capacity must be available at the same time as computing capacity, etc. Every aspect of such a system is dynamic: locating and scheduling resources, adapting running application systems to availability and congestion in the middleware and infrastructure, responding to human interaction, etc. The technologies, the middleware services, and the architectures that are used to build useful high-speed, wide area distributed systems, constitute the held of data intensive computing. This paper explores some of the history and future directions of that field, and describes a specific medical application example. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Lee, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,MS 50B-2239, Berkeley, CA 94720 USA. NR 11 TC 5 Z9 5 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65821-1 J9 LECT NOTES COMPUT SC PY 1999 VL 1593 BP 150 EP 158 PG 9 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods SC Computer Science GA BQ39Q UT WOS:000088252100017 ER PT S AU Moreira, JE Franke, H Chan, WM Fong, LL Jette, MA Yoo, A AF Moreira, JE Franke, H Chan, WM Fong, LL Jette, MA Yoo, A BE Sloot, P Bubak, M Hoekstra, A Hertzberger, B TI A gang-scheduling system for ASCI Blue-Pacific SO HIGH-PERFORMANCE COMPUTING AND NETWORKING, PROCEEDINGS SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 7th International Conference and Exhibition on High-Performance Computing and Networking (HPCN EUROPE 99) CY APR 12-14, 1999 CL AMSTERDAM, NETHERLANDS SP Dutch HPCN Fdn, Dutch Org Sci Res, Univ Amsterdam AB The ASCI Blue-Pacific machines are large parallel systems comprised of thousands of processors. We are currently developing and testing a gang-scheduling job control system for these machines that exploits space- and timesharing in the presence of dedicated communication devices. Our initial experience with this system indicates that, though applications pay a small overhead, overall system performance as measured by average job queue and response times improves significantly. This gang-scheduling system is planned for deployment into production mode during 1999 at Lawrence Livermore National Laboratory. C1 IBM Corp, Armonk, NY 10504 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Moreira, JE (reprint author), IBM Corp, Armonk, NY 10504 USA. EM jmoreira@us.ibm.com; frankeh@us.ibm.com; waimanc@us.ibm.com; llfong@us.ibm.com; jette@llnl.gov; ayoo@llnl.gov NR 12 TC 4 Z9 4 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65821-1 J9 LECT NOTES COMPUT SC PY 1999 VL 1593 BP 831 EP 840 PG 10 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods SC Computer Science GA BQ39Q UT WOS:000088252100084 ER PT S AU Evensky, DA Gentile, AC Wyckoff, P AF Evensky, DA Gentile, AC Wyckoff, P BE Sloot, P Bubak, M Hoekstra, A Hertzberger, B TI Lilith lights: A network traffic visualization tool for high performance clusters SO HIGH-PERFORMANCE COMPUTING AND NETWORKING, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 7th International Conference and Exhibition on High-Performance Computing and Networking (HPCN EUROPE 99) CY APR 12-14, 1999 CL AMSTERDAM, NETHERLANDS SP Dutch HPCN Fdn, Dutch Org Sci Res, Univ Amsterdam AB High performance computing increasingly utilizes loosely coupled clusters of commodity computers. Performance monitoring data on such platforms is traditionally performed by invasive message passing taps, and examined only after the run is complete. We present an alternative, designed to capitalize on the scalable nature of the platform. Lilith Lights is a non-invasive network and processor monitoring tool which collects and processes data from the individual cluster machines. The data is gathered and displayed concurrently with the running applications. The display format can correspond to the application's virtual topology or to the physical connectivity of the message passing hardware. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Evensky, DA (reprint author), Sandia Natl Labs, POB 969 MS 9011, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65821-1 J9 LECT NOTES COMPUT SC PY 1999 VL 1593 BP 1183 EP 1186 PG 4 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods SC Computer Science GA BQ39Q UT WOS:000088252100126 ER PT J AU Zhao, YS von Dreele, RB Morgan, JG AF Zhao, YS von Dreele, RB Morgan, JG TI A high P-T cell assembly for neutron diffraction up to 10 GPa and 1500 K SO HIGH PRESSURE RESEARCH LA English DT Article DE high pressure; high temperature; neutron diffraction; cell assembly ID PARIS-EDINBURGH CELL; POWDER DIFFRACTION; PRESSURE AB We present the design of a cell assembly for neutron diffraction experiments capable of performing simultaneous high-pressure (P) and high-temperature (T) conditions up to 10 GPa and 1500 K. The high P-T cell assembly, designed for a Paris- Edinburgh LPE) toroidal anvil press, consists of a ceramic gasket, a cylinder/disk furnace, a confining ring, two thermocouples, and platinum wires which serve as electrodes for ohmic heating of the sample. The properties of mechanical strength, yield strength for plastic deformation, thermal/electric insulation, and neutron transparency of the gasket materials are the keys to the success of the cell assembly. The high P-T neutron diffraction experiments conducted at the HIPD beam-line at LANSCE using this cell assembly have produced high quality data and with stable, uniform temperature and sustained hydrostatic pressure. C1 Univ Calif Los Alamos Natl Lab, LANSCE, Los Alamos, NM 87545 USA. RP Zhao, YS (reprint author), Univ Calif Los Alamos Natl Lab, LANSCE, MS-H805, Los Alamos, NM 87545 USA. RI Lujan Center, LANL/G-4896-2012 NR 17 TC 27 Z9 28 U1 0 U2 5 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0895-7959 J9 HIGH PRESSURE RES JI High Pressure Res. PY 1999 VL 16 IS 3 BP 161 EP 177 DI 10.1080/08957959908200289 PG 17 WC Physics, Multidisciplinary SC Physics GA 218ZQ UT WOS:000081582800002 ER PT S AU Olivier, SS Kartz, MW Bauman, BJ Brase, JM Brown, CG Cooke, JB Pennington, DM Silva, DA AF Olivier, SS Kartz, MW Bauman, BJ Brase, JM Brown, CG Cooke, JB Pennington, DM Silva, DA BE Gonglewski, JD Vorontsov, MA TI High-resolution wavefront control using liquid crystal spatial light modulators SO HIGH-RESOLUTION WAVEFRONT CONTROL: METHODS, DEVICES, AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on High-Resolution Wavefront Control - Methods, Devices, and Applications CY JUL 19-20, 1999 CL DENVER, CO SP SPIE DE adaptive optics; lasers; spatial light modulators; liquid crystals AB Liquid crystal spatial light modulator technology appropriate for high-resolution wavefront control has recently become commercially available. Some of these devices have several hundred thousand controllable degrees of freedom, more than two orders of magnitude greater than the largest conventional deformable mirror. We will present results of experiments to characterize the optical properties of these devices and to utilize them to correct aberrations in an optical system. We will also present application scenarios for these devices in high-power laser systems. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Olivier, SS (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 5 TC 7 Z9 7 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3246-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3760 BP 47 EP 51 DI 10.1117/12.367602 PG 5 WC Engineering, Electrical & Electronic; Optics; Physics, Condensed Matter SC Engineering; Optics; Physics GA BP45X UT WOS:000085205600006 ER PT S AU McDonald, TE Yates, GJ Cverna, FH Gallegos, RA Jaramillo, SA Numkena, DM Payton, J Pena-Abeyta, CR AF McDonald, TE Yates, GJ Cverna, FH Gallegos, RA Jaramillo, SA Numkena, DM Payton, J Pena-Abeyta, CR BE Frank, AM Walton, JS TI Range gated imaging experiments using gated intensifiers SO HIGH-SPEED IMAGING AND SEQUENCE ANALYSIS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on High-Speed Imaging and Sequence Analysis CY JAN 28-29, 1999 CL SAN JOSE, CA SP SPIE, Soc Imaging Sci & Technol DE range gated imaging; LADAR; scattering media imaging AB A variety of range gated imaging experiments using high-speed gated/shuttered proximity focused microchannel plate image intensifiers (MCPII) are reported. Range gated imaging experiments were conducted in water for detection of submerged mines in controlled turbidity tank test and in sea water for the Naval Coastal Sea Command/U.S. Marine Corps. Field experiments have been conducted consisting of kilometer range imaging of resolution targets and military vehicles in atmosphere at Eglin Air Force Base for the U.S. Air force, and similar imaging experiments, but in smoke environment, at Redstone Arsenal for the U.S. Army Aviation and Missile Command (AMCOM). Wavelength of the illuminating laser was 532nm with pulse widths ranging from 6 to 12ns and comparable gate widths. These testes have shown depth resolution in the tens of centimeters range from time phasing reflected LADAR images with MCPII shutter opening. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP McDonald, TE (reprint author), Univ Calif Los Alamos Natl Lab, P-23,MS H803, Los Alamos, NM 87545 USA. NR 8 TC 11 Z9 12 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3113-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3642 BP 142 EP 148 PG 7 WC Engineering, Electrical & Electronic; Optics; Imaging Science & Photographic Technology SC Engineering; Optics; Imaging Science & Photographic Technology GA BN19Z UT WOS:000081054300014 ER PT B AU Wagh, AS Jeong, SY Singh, D AF Wagh, AS Jeong, SY Singh, D BE Azizinamini, A Darwin, D French, C TI High strength phosphate cement using industrial byproduct ashes SO HIGH STRENGTH CONCRETE, PROCEEDINGS LA English DT Proceedings Paper CT 1st International Engineering Foundation Conference on High Strength Concrete CY JUL 13-18, 1997 CL KONA, HI SP United Engn Fdn Inc AB During our effort to stabilize contaminated ashes in the U.S. Department of Energy's (DOE's) complex by a novel chemically bonded phosphate ceramic, we formulated a high strength concrete made of benign ashes (such as fly ash and coal bottom ash) that may be useful for specialized applications in construction industry. It is formed by a room temperature process in which MgO is reacted with a solution of one of the soluble hydrophosphates to form a dense matrix. Any ash or slag may be incorporated during the reaction. The slurry formed by mixing these components for 15-30 minutes is a pourable, low viscosity paste. Once it is left undisturbed, it sets into a hard mass in approximate to 45 minutes with a small amount of heat evolution. Its density ranges between 1.7 g/cc to 2.0 g/cc, open porosity is <5%. For a typical ash loading of 60 wt. %, it has a strength of approximate to 12,000 psi. The microstructure of the concrete is glass-crystalline. This product is not very sensitive to the ash composition. Unlike in portland cement, it is unaffected by the unburnt carbon in the ash or to any Ct ions, and thus a wide variety of combustion products may be incorporated to develop this product. The material cost is generally 50% higher than portland cement, but processing advantages, such as faster setting, setting in cold environment, and self binding characteristics may off-set some of the costs, or improved properties may justify slightly higher costs for specialized product development. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Wagh, AS (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 5 TC 1 Z9 1 U1 3 U2 6 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0419-4 PY 1999 BP 542 EP 553 PG 4 WC Construction & Building Technology; Engineering, Civil SC Construction & Building Technology; Engineering GA BP30H UT WOS:000084624400043 ER PT S AU Serizawa, H Lewinsohn, CA Youngblood, GE Jones, RH Johnston, DE Kohyama, A AF Serizawa, H Lewinsohn, CA Youngblood, GE Jones, RH Johnston, DE Kohyama, A BE Niihara, K Nakano, K Sekino, T Yasuda, E TI High-temperature properties of newly developed advanced SiC fibers SO HIGH TEMPERATURE CERAMIC MATRIX COMPOSITES III SE KEY ENGINEERING MATERIALS LA English DT Article; Proceedings Paper CT 3rd International Conference on High Tempurature Ceramic Matrix Composites (HT-CMC 3) CY SEP 06-09, 1998 CL OSAKA, JAPAN SP Ceram Soc Japan, Amer Ceram Soc, European Ceram Soc, Fine Ceram Res Assoc DE SiC fibers; ceramics; high temperature; oxidation; composites ID SILICON-CARBIDE; STRENGTH; LENGTH AB As a result of R & D efforts for silicon carbide (SIC) fibers, near-stoichiometric and highly crystalline SIC fiber (Hi-Nicalon type S) has been developed. In this research, to estimate the potential capability of Hi-Nicalon type S for reinforcement of ceramic matrix composites, fiber tensile tests at high temperature and fiber oxidation tests at 1373 K were carried out. Hi-Nicalon fibers were also tested to compare with Hi-Nicalon type S. From the results of research for effects of gauge length on fiber strength, the strength-gauge length relationship of Hi-Nicalon type S was found to follow the weakest-link rule. The results of tensile tests at high temperature indicated that the strength of Hi-Nicalon type S slightly increased with increasing test temperature. Finally, from the SEM observation results of oxidized fibers, the oxidation behavior of Hi-Nicalon type S was found to fit the Deal/Grove linear-parabolic model. C1 Osaka Univ, Joining & Welding Res Inst, Ibaraki, Osaka 567, Japan. Pacific NW Lab, Richland, WA 99352 USA. Univ Washington, Associated Western Univ, Seattle, WA 98195 USA. Kyoto Univ, Inst Adv Energy, Uji, Kyoto 611, Japan. RP Serizawa, H (reprint author), Osaka Univ, Joining & Welding Res Inst, 11-1 Mihogaoka, Ibaraki, Osaka 567, Japan. NR 15 TC 2 Z9 2 U1 2 U2 4 PU TRANS TECH PUBLICATIONS PI CLAUSTHAL ZELLERFE PA EINERSBERGER BLICK 28, PO BOX 266, W-3392 CLAUSTHAL ZELLERFE, GERMANY SN 1013-9826 BN 0-87849-818-4 J9 KEY ENG MAT PY 1999 VL 164-1 BP 287 EP 290 PG 4 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BN11H UT WOS:000080750200066 ER PT S AU Lewinsohn, CA Henager, CH Jones, RH AF Lewinsohn, CA Henager, CH Jones, RH BE Niihara, K Nakano, K Sekino, T Yasuda, E TI Subcritical crack growth mechanisms and failure mechanism maps for ceramic matrix composites SO HIGH TEMPERATURE CERAMIC MATRIX COMPOSITES III SE KEY ENGINEERING MATERIALS LA English DT Article; Proceedings Paper CT 3rd International Conference on High Tempurature Ceramic Matrix Composites (HT-CMC 3) CY SEP 06-09, 1998 CL OSAKA, JAPAN SP Ceram Soc Japan, Amer Ceram Soc, European Ceram Soc, Fine Ceram Res Assoc DE subcritical crack growth; oxidation; failure; interfaces; lifetime ID HIGH-TEMPERATURE; ELEVATED-TEMPERATURES; STRESS-RUPTURE; NICALON; EMBRITTLEMENT; OXIDATION; CARBON; AIR AB Numerous studies have indicated that time-dependent subcritical crack growth, at elevated temperatures, in ceramic matrix composites (CMCs) is caused by a number of mechanisms. The most commonly observed crack growth mechanisms will be described. The results of an investigation of the conditions in which each mechanism controls the rate of subcritical crack growth will be used to construct failure mechanism maps. The failure mechanism maps illustrate regions of temperature and oxygen concentration where each crack growth mechanism operates. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Lewinsohn, CA (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. OI Henager, Chuck/0000-0002-8600-6803 NR 17 TC 0 Z9 0 U1 0 U2 0 PU TRANS TECH PUBLICATIONS PI CLAUSTHAL ZELLERFE PA EINERSBERGER BLICK 28, PO BOX 266, W-3392 CLAUSTHAL ZELLERFE, GERMANY SN 1013-9826 BN 0-87849-818-4 J9 KEY ENG MAT PY 1999 VL 164-1 BP 333 EP 336 PG 4 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BN11H UT WOS:000080750200076 ER PT S AU Jones, RH Lewinsohn, CA Youngblood, GE Kohyama, A AF Jones, RH Lewinsohn, CA Youngblood, GE Kohyama, A BE Niihara, K Nakano, K Sekino, T Yasuda, E TI Properties of advanced fibers for SiC SiC composite applications in fusion energy systems SO HIGH TEMPERATURE CERAMIC MATRIX COMPOSITES III SE KEY ENGINEERING MATERIALS LA English DT Article; Proceedings Paper CT 3rd International Conference on High Tempurature Ceramic Matrix Composites (HT-CMC 3) CY SEP 06-09, 1998 CL OSAKA, JAPAN SP Ceram Soc Japan, Amer Ceram Soc, European Ceram Soc, Fine Ceram Res Assoc DE fibers; ceramic; composites; high-temperature; radiation AB Silicon carbide composites are attractive for structural applications in fusion energy systems because of their low activation and afterheat characteristics coupled with their excellent high-temperature properties. These new materials will require optimization of their thermal conductivity, radiation stability, chemical compatibility in fusion relevant environments, hermetic properties and joining methodology before they can be utilized effectively in a fusion energy system. Development of advanced SIC fibers, such as Hi-Nicalon, Hi-Nicalon(TM) Type S and DOW/Corning Sylramic fibers have resulted in higher strengths, improved creep resistance and thermal conductivity with the added benefit of radiation stability for fusion applications. C1 Pacific NW Lab, Richland, WA 99352 USA. Kyoto Univ, Inst Adv Energy, Uji, Kyoto 611, Japan. RP Jones, RH (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 8 TC 8 Z9 8 U1 1 U2 6 PU TRANS TECH PUBLICATIONS PI CLAUSTHAL ZELLERFE PA EINERSBERGER BLICK 28, PO BOX 266, W-3392 CLAUSTHAL ZELLERFE, GERMANY SN 1013-9826 BN 0-87849-818-4 J9 KEY ENG MAT PY 1999 VL 164-1 BP 405 EP 408 PG 4 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BN11H UT WOS:000080750200091 ER PT S AU Emery, VJ Kivelson, SA AF Emery, VJ Kivelson, SA BE Barnes, SE Ashkenazi, J Cohn, JL Zuo, F TI Local electronic structure and high temperature superconductivity. SO HIGH TEMPERATURE SUPERCONDUCTIVITY SE AIP Conference Proceedings LA English DT Proceedings Paper CT Conference on High Temperature Superconductivity CY JAN 07-13, 1999 CL UNIV MIAMI, CORAL GABLES, FL SP Univ Miami HO UNIV MIAMI ID T-C SUPERCONDUCTORS; MUON SPIN ROTATION; PHASE-SEPARATION; NORMAL-STATE; TRANSITION TEMPERATURE; GAP ANISOTROPY; FERMI-SURFACE; LANDAU THEORY; J MODEL; BI2SR2CACU2O8+DELTA AB It is argued that a new mechanism and many-body theory of superconductivity are required for doped correlated insulators. Here we review the essential features of and the experimental support for such a theory, in which the physics is driven by the kinetic energy. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Emery, VJ (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 52 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 0094-243X BN 1-56396-880-0 J9 AIP CONF PROC PY 1999 VL 483 BP 37 EP 44 DI 10.1063/1.59581 PG 8 WC Physics, Condensed Matter SC Physics GA BN91R UT WOS:000083461600006 ER PT S AU Klemm, RA Rieck, CT Scharnberg, K AF Klemm, RA Rieck, CT Scharnberg, K BE Barnes, SE Ashkenazi, J Cohn, JL Zuo, F TI c-axis twist Bi2Sr2CaCu2O8+delta Josephson junctions: A new phase-sensitive test of order parameter symmetry SO HIGH TEMPERATURE SUPERCONDUCTIVITY SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on High Temperature Superconductivity CY JAN 07-13, 1999 CL UNIV MIAMI, CORAL GABLES, FL SP Univ Miami HO UNIV MIAMI AB Li et al, found that the critical current density J(c)(J) across atomically clean c-axis twist junctions of Bi2Sr2Ca Cu2O8+delta is the same as that of the constituent single crystal, J(c)(S), independent of the twist angle phi(o), even at T-c. We investigated theoretically if a d(x)(2)-y(2)-wave order parameter might twist by mixing in d(xy) components, but find that such twisting cannot possibly explain the data near to T-c. Hence, the order parameter contains an s-wave component, but not any d(x)(2)-y(2)-wave component. In addition, the c-axis Josephson tunneling is completely incoherent. We also propose a c-axis junction tricrystal experiment which does not rely upon expensive substrates. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Klemm, RA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 8 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 0094-243X BN 1-56396-880-0 J9 AIP CONF PROC PY 1999 VL 483 BP 259 EP 264 DI 10.1063/1.59596 PG 6 WC Physics, Condensed Matter SC Physics GA BN91R UT WOS:000083461600045 ER PT S AU McQueeney, RJ Sarrao, JS AF McQueeney, RJ Sarrao, JS BE Barnes, SE Ashkenazi, J Cohn, JL Zuo, F TI Evidence for strong electron-lattice coupling in La2-xSrxNiO4 SO HIGH TEMPERATURE SUPERCONDUCTIVITY SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on High Temperature Superconductivity CY JAN 07-13, 1999 CL UNIV MIAMI, CORAL GABLES, FL SP Univ Miami HO UNIV MIAMI ID CHARGE AB The inelastic neutron scattering spectra were measured for several Sr concentrations of polycrystalline La2-xSrxNiO4. We find that the generalized phonon density-of-states is identical for a = 0 and x = 1/8. For a = 1/3 and a: = 1/2, the band of phonons corresponding to the in-plane oxygen vibrations (> 65 meV) splits into two subbands centered at 75 meV and 85 meV. The lower frequency band increases in amplitude for the a: = 1/2 sample, indicating that it is directly related to the hole concentration. These changes are associated with the coupling of oxygen vibrations to doped holes which reside in the NiO2 planes and are a signature of strong electron-lattice coupling. Comparison of La1.9Sr0.1CuO4 and La1.875ST0.125NiO4 demonstrates that much stronger electron-lattice coupling occurs for particular modes in the cuprate for modest doping and is likely related to the metallic nature of the cuprate. C1 Univ Calif Los Alamos Natl Lab, Lujan Ctr, Los Alamos, NM 87545 USA. RP McQueeney, RJ (reprint author), Univ Calif Los Alamos Natl Lab, Lujan Ctr, POB 1663, Los Alamos, NM 87545 USA. NR 12 TC 0 Z9 0 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-880-0 J9 AIP CONF PROC PY 1999 VL 483 BP 278 EP 283 DI 10.1063/1.59627 PG 6 WC Physics, Condensed Matter SC Physics GA BN91R UT WOS:000083461600049 ER PT S AU Norman, MR AF Norman, MR BE Barnes, SE Ashkenazi, J Cohn, JL Zuo, F TI Fermi surfaces, Fermi patches, and Fermi arcs in high T-c superconductors SO HIGH TEMPERATURE SUPERCONDUCTIVITY SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on High Temperature Superconductivity CY JAN 07-13, 1999 CL UNIV MIAMI, CORAL GABLES, FL SP Univ Miami HO UNIV MIAMI ID ANGLE-RESOLVED PHOTOEMISSION; GAP ANISOTROPY; NORMAL-STATE; BI2SR2CACU2O8+DELTA; PSEUDOGAP; DISPERSION; EVOLUTION; FLUCTUATIONS; YBA2CU3O6+X; SYSTEM AB A defining property of metals is the existence of a Fermi surface: for two dimensions, a continuous contour in momentum space which separates occupied from unoccupied states. In this paper, I discuss angle resolved photoemission data on the cuprate superconductor BSCCO and argue that it is not best thought of in this conventional picture. Rather, the data are consistent with "patches" of finite area connected by more conventional "arcs". Novel physics is associated with the patches, in that the states contained in a patch are dispersionless and thus interaction dominated. In the pseudogap phase, the patches are gapped out, leaving the Fermi arcs disconnected. This unusual situation may be the key to understanding the microscopic physics of the high temperature superconductors, in that the pairing correlations are strongest in the patches, yet the superfluid density lives only on the area. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Norman, MR (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Norman, Michael/C-3644-2013 NR 32 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-880-0 J9 AIP CONF PROC PY 1999 VL 483 BP 298 EP 303 DI 10.1063/1.59631 PG 6 WC Physics, Condensed Matter SC Physics GA BN91R UT WOS:000083461600053 ER PT S AU Phillips, NE Fisher, RA Schilling, A Buffeteau, B Hargreaves, TE Marcenat, C Calemczuk, F O'Connor, AS Dennis, KW McCallum, RW AF Phillips, NE Fisher, RA Schilling, A Buffeteau, B Hargreaves, TE Marcenat, C Calemczuk, F O'Connor, AS Dennis, KW McCallum, RW BE Barnes, SE Ashkenazi, J Cohn, JL Zuo, F TI The specific heat of (La1.85Sr0.15)CuO4: Evidence for d-wave pairing SO HIGH TEMPERATURE SUPERCONDUCTIVITY SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on High Temperature Superconductivity CY JAN 07-13, 1999 CL UNIV MIAMI, CORAL GABLES, FL SP Univ Miami HO UNIV MIAMI ID DENSITY-OF-STATES; MAGNETIC-FIELD DEPENDENCE; TEMPERATURE SPECIFIC-HEAT; MIXED-STATE; SUPERCONDUCTORS; LA2-XSRXCUO4; VORTEX AB Measurements of the specific heat of two samples of (La1.85Sr0.15)CuO4 in the superconducting and vortex states show evidence of the line nodes in the energy gap associated with d-wave pairing. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, MSD, Berkeley, CA 94720 USA. RP Phillips, NE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, MSD, Berkeley, CA 94720 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-880-0 J9 AIP CONF PROC PY 1999 VL 483 BP 310 EP 313 DI 10.1063/1.59598 PG 4 WC Physics, Condensed Matter SC Physics GA BN91R UT WOS:000083461600055 ER PT S AU Tranquada, JM AF Tranquada, JM BE Barnes, SE Ashkenazi, J Cohn, JL Zuo, F TI Experimental evidence for topological doping in the cuprates SO HIGH TEMPERATURE SUPERCONDUCTIVITY SE AIP Conference Proceedings LA English DT Proceedings Paper CT Conference on High Temperature Superconductivity CY JAN 07-13, 1999 CL UNIV MIAMI, CORAL GABLES, FL SP Univ Miami HO UNIV MIAMI ID MAGNETIC FLUCTUATIONS; NEUTRON-SCATTERING; YBA2CU3O6.6; ANTIFERROMAGNETISM; SUSCEPTIBILITY; LA2-XSRXCUO4; STRIPES; PHASES; STATE AB Some recent experiments that provide support for the concept of topological doping in cuprate superconductors are discussed. Consistent with the idea of charge segregation, it is argued that the scattering associated with the "resonance" peak found in YBa2Cu3O6+x and Bi2Sr2CaCu2O8+delta comes from the Cu spins and not from the doped holes. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Tranquada, JM (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Tranquada, John/A-9832-2009 OI Tranquada, John/0000-0003-4984-8857 NR 31 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-880-0 J9 AIP CONF PROC PY 1999 VL 483 BP 336 EP 340 DI 10.1063/1.59636 PG 5 WC Physics, Condensed Matter SC Physics GA BN91R UT WOS:000083461600060 ER PT S AU Louca, D Kwei, GH AF Louca, D Kwei, GH BE Barnes, SE Ashkenazi, J Cohn, JL Zuo, F TI Local lattice effects in oxides SO HIGH TEMPERATURE SUPERCONDUCTIVITY SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on High Temperature Superconductivity CY JAN 07-13, 1999 CL UNIV MIAMI, CORAL GABLES, FL SP Univ Miami HO UNIV MIAMI ID LACOO3 AB Neutron diffraction measurements were used to investigate the local atomic structure of manganese and cobalt oxides. Static Jahn-Teller (JT) distortions present in the lightly doped perovskite manganates were found in metallic compositions as well. The cooperativeness of the distortions is however lost as the doping is increased. In the two-layer manganates, the existence of a local JT effect helps explain the similarities in the properties between cubic and layered systems. In the cobalt system, the coupling strength of the lattice to the e(g) states during the thermal activation from the ground, low-spin (LS) state to an excited, intermediate (IS) or high-spin (HS) states for Co in LaCoO3 changes as a function of temperature. The introduction of extra carriers by doping of La1-xSrxCoO3 stabilizes the IS JT states, populated at a rate proportional to the charge density. The JT distortions induced in this system are dynamic in nature if compared to the ones in the manganates. C1 Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. RP Louca, D (reprint author), Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, MST 10,MS K764, Los Alamos, NM 87545 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-880-0 J9 AIP CONF PROC PY 1999 VL 483 BP 400 EP 406 DI 10.1063/1.59604 PG 7 WC Physics, Condensed Matter SC Physics GA BN91R UT WOS:000083461600070 ER PT B AU Balachandran, U AF Balachandran, U BE Tendeloo, GV Antipov, EV Putilin, SN TI Recent advances in fabrication of high-T-c superconductors for electric power applications SO HIGH-TEMPERATURE SUPERCONDUCTORS AND NOVEL INORGANIC MATERIALS SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 3, HIGH TECHNOLOGY LA English DT Proceedings Paper CT NATO Advanced Workshop on High-Temperature Superconductors and Novel Inorganic Materials Engineering MSU-HTSC V CY MAR 24-29, 1998 CL MOSCOW, RUSSIA SP NATO ID CRITICAL-CURRENT-DENSITY; THIN-LAYER; SILVER; TAPES; WIRES; AG C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Balachandran, U (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 25 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5345-5 J9 NATO ASI 3 HIGH TECH PY 1999 VL 62 BP 1 EP 9 PG 9 WC Chemistry, Multidisciplinary; Chemistry, Inorganic & Nuclear; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA BM62Z UT WOS:000079308200001 ER PT B AU Jorgensen, JD Chmaissem, O Hinks, DG Knizhnik, A Eckstein, Y Shaked, H Wagner, JL Dabrowski, B Short, S Mitchell, JF Hodges, JP AF Jorgensen, JD Chmaissem, O Hinks, DG Knizhnik, A Eckstein, Y Shaked, H Wagner, JL Dabrowski, B Short, S Mitchell, JF Hodges, JP BE Tendeloo, GV Antipov, EV Putilin, SN TI Novel structural phenomena at the maximum T-c in 123 and HgBa2CuO4+delta superconductors: Evidence for structural response that competes with superconductivity SO HIGH-TEMPERATURE SUPERCONDUCTORS AND NOVEL INORGANIC MATERIALS SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 3, HIGH TECHNOLOGY LA English DT Proceedings Paper CT NATO Advanced Workshop on High-Temperature Superconductors and Novel Inorganic Materials Engineering MSU-HTSC V CY MAR 24-29, 1998 CL MOSCOW, RUSSIA SP NATO ID ORGANIC SUPERCONDUCTORS; TRANSITION-TEMPERATURE; ELECTRONIC-STRUCTURE; CHEVREL PHASES; CUO2 PLANES; (CAXLA1-X)(BA1.75-XLA0.25+X)CU3OY; YBA2CU3OX; TRANSFORMATION; INSTABILITY; PRESSURE AB Structural distortions that compete with superconductivity have been investigated in two systems where oxygen content can be used to vary the doping continuously from the under doped state, through the maximum T-c into the over doped state. In the 123 system, (La1-xCax)(Ba1.75-xLa0.25+x)Cu3O7+delta, the buckling of the CuO2 planes goes through a maximum at the maximum T-c. In HgBa2CuO4+delta, where buckling of the CuO2 planes is not available as a structural degree of freedom, there is a plateau at the maximum T-c where the unit cell volume expands as oxygen is added while the charge transfer and T-c remain constant. These unusual structural phenomena upon crossing through the maximum T-c are hypothesized to be a response of the crystal structure to the electronic structure, with the structural distortions competing with superconductivity, or lowering the T-c from what it would otherwise be. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Jorgensen, JD (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Hodges, Jason/K-1421-2013 NR 27 TC 4 Z9 4 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5345-5 J9 NATO ASI 3 HIGH TECH PY 1999 VL 62 BP 109 EP 116 PG 8 WC Chemistry, Multidisciplinary; Chemistry, Inorganic & Nuclear; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA BM62Z UT WOS:000079308200018 ER PT B AU McCallum, RW Wu, H Dennis, KW Kramer, MJ AF McCallum, RW Wu, H Dennis, KW Kramer, MJ BE Tendeloo, GV Antipov, EV Putilin, SN TI Cation substitution, second phase precipitation, superconductivity, and flux pinning in LRE1+xBa2-xCu3O7 SO HIGH-TEMPERATURE SUPERCONDUCTORS AND NOVEL INORGANIC MATERIALS SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 3, HIGH TECHNOLOGY LA English DT Proceedings Paper CT NATO Advanced Workshop on High-Temperature Superconductors and Novel Inorganic Materials Engineering MSU-HTSC V CY MAR 24-29, 1998 CL MOSCOW, RUSSIA SP NATO ID CU-O SYSTEM; ND1+XBA2-XCU3O7+DELTA; EQUILIBRIA C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP McCallum, RW (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5345-5 J9 NATO ASI 3 HIGH TECH PY 1999 VL 62 BP 199 EP 204 PG 6 WC Chemistry, Multidisciplinary; Chemistry, Inorganic & Nuclear; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA BM62Z UT WOS:000079308200034 ER PT J AU Meder, R Gallagher, S Mackie, KL Bohler, H Meglen, RR AF Meder, R Gallagher, S Mackie, KL Bohler, H Meglen, RR TI Rapid determination of the chemical composition and density of Pinus radiata by PLS modelling of transmission and diffuse reflectance FTIR spectra SO HOLZFORSCHUNG LA English DT Article DE Pinus radiata; FTIR; DRIFT; PLS; lignin; carbohydrates; extractives; density ID PULP; WOOD; SOFTWOOD; NMR AB Transmission and diffuse reflectance FTIR spectra of samples of Pinus radiata wood have been used as the basis of PLS-1 (partial least squares) and PLS-2 (projection to latent structures) models for the prediction of extractives, lignin, total carbohydrate and basic density. Very little difference was observed between models based on transmission spectra and those based on diffuse reflectance spectra. Because of the ease of sample preparation and presentation the diffuse reflectance technique was chosen as the method of preference. Similarly very little difference was observed between models prepared using PLS-1 and models prepared using PLS-2 correlations of diffuse reflectance spectra. Multiple correlation coefficients between the four measured properties and the diffuse reflectance spectra using PLS-2 modelling with four principal components are respectively: extractives, 0.87; Klason lignin, 0.84; total carbohydrate, 0.58; and density, 0.87. C1 New Zealand Forest Res Inst Ltd, Rotorua, New Zealand. Fachhsch Tech & Wirtschaft Reutlingen, Inst Angew Forsch, D-72762 Reutlingen, Germany. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Meder, R (reprint author), New Zealand Forest Res Inst Ltd, Private Bag 3020, Rotorua, New Zealand. RI Meder, Roger/A-7071-2011 NR 22 TC 54 Z9 57 U1 0 U2 6 PU WALTER DE GRUYTER & CO PI BERLIN PA GENTHINER STRASSE 13, D-10785 BERLIN, GERMANY SN 0018-3830 J9 HOLZFORSCHUNG JI Holzforschung PY 1999 VL 53 IS 3 BP 261 EP 266 DI 10.1515/HF.1999.044 PG 6 WC Forestry; Materials Science, Paper & Wood SC Forestry; Materials Science GA 200CF UT WOS:000080521000007 ER PT B AU Hughes, DA Godfrey, A AF Hughes, DA Godfrey, A BE Bieler, TR Lalli, LA MacEwen, SR TI Dislocation structures formed during hot and cold working SO HOT DEFORMATION OF ALUMINUM ALLOYS II LA English DT Proceedings Paper CT 2nd Symposium on Hot Deformation of Aluminum Alloys, at the 1998 TMS Fall Meeting CY OCT 11-15, 1998 CL ROSEMONT, IL SP Minerals Met & Mat Soc ID DYNAMIC RESTORATION MECHANISMS; ALUMINUM-ALLOYS; MICROSTRUCTURAL EVOLUTION; DEFORMATION STRUCTURES; STRAIN-RATE; MG ALLOY; ROLL GAP; AL-MG; ORIENTATION; BOUNDARIES AB During many types of deformation, grains are subdivided into smaller regions by dislocation boundaries. The classification of structures formed by grain subdivision has differed between structures observed following cold deformation and hot deformation. Cold deformed microstructures are characterized by grain subdivision at two size scales. Grain subdivision occurs at the larger scale by geometrically necessary boundaries that delineate differently deforming blocks that contain nearly equiaxed cells. In contrast hot deformed structures have been described with a single level of subdivision by equiaxed subgrains. Infrequently an occasional long boundary provides subdivision at a larger level. However, new findings in warm to hot deformed alloys show that there are closer ties between the cold and hot deformed structures. Specifically, two levels of grain subdivision are observed following some types of high temperature deformation when large areas are surveyed in the TEM. Furthermore, the probability densities of boundary misorientation angles at high temperature show the same universal scaling as those at low temperature. C1 Sandia Natl Labs, Ctr Mat Sci & Engn, Livermore, CA 94550 USA. RP Hughes, DA (reprint author), Sandia Natl Labs, Ctr Mat Sci & Engn, POB 969,MS 9403, Livermore, CA 94550 USA. NR 36 TC 0 Z9 0 U1 0 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-412-7 PY 1999 BP 23 EP 36 PG 14 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BM95N UT WOS:000080239000003 ER PT B AU Chen, SR Stout, MG Kocks, UF MacEwen, SR Beaudoin, AJ AF Chen, SR Stout, MG Kocks, UF MacEwen, SR Beaudoin, AJ BE Bieler, TR Lalli, LA MacEwen, SR TI Constitutive modeling of a 5182 aluminum as a function of strain rate and temperature SO HOT DEFORMATION OF ALUMINUM ALLOYS II LA English DT Proceedings Paper CT 2nd Symposium on Hot Deformation of Aluminum Alloys, at the 1998 TMS Fall Meeting CY OCT 11-15, 1998 CL ROSEMONT, IL SP Minerals Met & Mat Soc AB We have measured the stress/strain response of a 5182 aluminum alloy as a function of strain rate and temperature. As one expects, at room temperature and quasi-static strain rate this alloy exhibits dynamic strain aging with negative strain-rate sensitivity. At higher temperature, we have separated the response into two categories, when the material displays a yield drop and when it does not. The yield drop was only observed if the yield stress was below 70MPa. In this case the work-hardening curve was for practical purposes flat. Within this regime the deformation has been labeled "Class A" behavior. Tt occurs by continuous motion of dislocations accompanied by diffusion of solute. It is further shown that a constitutive relation such as (epsilon) over dot = A(sigma/mu)(n) . mu b(3)/kT . exp(-Q(D)/kT) is appropriate to describe deformation in this temperature/strain-rate regime where the solute drag mechanism dominates. In this expression Q(D) is the activation enthalpy for self diffusion of Mg in aluminum, which is 131 kJ/mol. In the high-stress regime, where the yield stress is above 80MPa, there is positive work hardening associated with flow stress behavior of the 5182 alloy. The yield stress was nearly constant; however, the hardening and saturation flow stress increases with decreasing temperature and increasing strain rate. In this regime the deformation is dominated by dislocation accumulation and dynamic recovery. We have found that the Mechanical Threshold Strength(MTS) model accurately describes the constitutive response as a function of temperature and strain rate. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 16 TC 0 Z9 0 U1 0 U2 3 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-412-7 PY 1999 BP 205 EP 216 PG 12 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BM95N UT WOS:000080239000018 ER PT B AU Stout, MG Chen, SR Kocks, UF Schwartz, AJ MacEwen, SR Beaudoin, AJ AF Stout, MG Chen, SR Kocks, UF Schwartz, AJ MacEwen, SR Beaudoin, AJ BE Bieler, TR Lalli, LA MacEwen, SR TI Mechanisms responsible for texture development in a 5182 aluminum alloy deformed at elevated temperature SO HOT DEFORMATION OF ALUMINUM ALLOYS II LA English DT Proceedings Paper CT 2nd Symposium on Hot Deformation of Aluminum Alloys, at the 1998 TMS Fall Meeting CY OCT 11-15, 1998 CL ROSEMONT, IL SP Minerals Met & Mat Soc ID HOT-ROLLING TEXTURES; FCC METALS; POLYCRYSTALS; DEFORMATION AB The textures that develop in a 5182 aluminum alloy as a result of monotonic high-temperature compression have been investigated. We found that the deformation texture was a function of temperature. For compressive deformation at 300 degrees C and below the material formed the classic (101) deformation texture, while the material develops a texture that is a combination of the classical uniaxial compression deformation texture, (101), and static recrystallization texture, (001), as a result of the deformation alone when the deformation temperature was at and above 400 degrees C. Our investigation has focused on determining the mechanism responsible for the development of this unusual progression of deformation textures. In order to understand the mechanism(s) responsible for this particular development, we have performed interrupted compression experiments as well as microstructural analyses. The deformation experiments consisted of deforming to a given strain, holding at temperature for various times at zero strain rate, followed by either quenching or further deformation. In addition we have performed orientation imaging microscopy (OIM) to identify the shapes of grains with particular orientations and grain-to-grain orientation relationships. Finally, crystal plasticity theory was used to model whether or not deformation via different slip systems and high strain-rate sensitivity could produce the (101) and (001) texture components. Our conclusions are summarized as follows: The texture development is not a result of static processes, i.e, static recrystallization at the various hold times altered neither the textures nor the constitutive behavior. Simulation using a crystal plasticity model indicates that the combination of a cube component prevalent in the original texture, slip activity on 011 planes, and increased rate sensitivity leads to a combined (001) and (101) texture. Finally, the microscopic OIM results are consistent with these observations. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Stout, MG (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 14 TC 0 Z9 0 U1 1 U2 3 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-412-7 PY 1999 BP 243 EP 254 PG 12 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BM95N UT WOS:000080239000021 ER PT B AU Radhakrishnan, B Sarma, G Zacharia, T AF Radhakrishnan, B Sarma, G Zacharia, T BE Bieler, TR Lalli, LA MacEwen, SR TI Coupled finite element-Monte Carlo simulation of microstructure and texture evolution during thermomechanical processing SO HOT DEFORMATION OF ALUMINUM ALLOYS II LA English DT Proceedings Paper CT 2nd Symposium on Hot Deformation of Aluminum Alloys, at the 1998 TMS Fall Meeting CY OCT 11-15, 1998 CL ROSEMONT, IL SP Minerals Met & Mat Soc ID COMPUTER-SIMULATION; RECRYSTALLIZATION; GROWTH; NUCLEATION; METALS AB A novel simulation technique for predicting the microstructure and texture evolution during thermomechanical processing is presented. The technique involves coupling a finite element microstructural deformation model based on crystal plasticity with a Monte Carlo simulation of recovery and recrystallization. The finite element model captures the stored energy and the crystallographic orientation distributions in the deformed microstructure. The Monte Carlo simulation captures the microstructural evolution associated with recovery and recrystallization. A unique feature of the Monte Carlo simulation is that it treats recrystallization as a heterogeneous subgrain growth process, thus providing the natural link between nucleation and growth phenomena, and quantifying the role of recovery in these phenomena. Different nucleation mechanisms based on heterogeneous subgrain growth as well as strain induced boundary migration are automatically included in the recrystallization simulation. The simulations are shown to account for the extent of prior deformation on the microstructure and kinetics of recrystallization during subsequent annealing. The simulations also capture the influence of the presence of cube orientations in the initial microstructure, and the operation of non-octahedral slip during deformation of fee polycrystals, on the recrystallization texture. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Radhakrishnan, B (reprint author), Oak Ridge Natl Lab, POB 2008,MS-6140, Oak Ridge, TN 37831 USA. NR 14 TC 0 Z9 0 U1 0 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-412-7 PY 1999 BP 267 EP 278 PG 12 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BM95N UT WOS:000080239000023 ER PT B AU Sarma, G Radhakrishnan, B Zacharia, T AF Sarma, G Radhakrishnan, B Zacharia, T BE Bieler, TR Lalli, LA MacEwen, SR TI Polycrystal simulations of texture evolution during deformation processing SO HOT DEFORMATION OF ALUMINUM ALLOYS II LA English DT Proceedings Paper CT 2nd Symposium on Hot Deformation of Aluminum Alloys, at the 1998 TMS Fall Meeting CY OCT 11-15, 1998 CL ROSEMONT, IL SP Minerals Met & Mat Soc ID PLANE-STRAIN COMPRESSION; ROLLING TEXTURES; FCC METALS; CRYSTALS; PLASTICITY AB Some recent research on the hot deformation of aluminum alloys has indicated that at elevated temperatures, slip occurs on {110}[110] systems in addition to the usual {111}[110] systems active at lower temperatures. The effect of these additional slip systems on the texture evolution of aluminum single and polycrystals is studied using finite element simulations. The crystals are deformed in plane strain compression, and the constitutive response is modeled using crystal plasticity to track the reorientation of the crystals. By discretizing each crystal with a large number of elements, the non-uniform deformations due to local inhomogeneities and interactions with neighboring crystals are modeled. The resulting textures and microstructures are examined with regard to effect of including the additional systems, initial orientation of the single crystals, and stability of the cube orientation. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Sarma, G (reprint author), Oak Ridge Natl Lab, POB 2008,MS-6140, Oak Ridge, TN 37831 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-412-7 PY 1999 BP 279 EP 290 PG 12 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BM95N UT WOS:000080239000024 ER PT B AU Engler, O Vatne, HE AF Engler, O Vatne, HE BE Bieler, TR Lalli, LA MacEwen, SR TI Modeling of the recrystallization textures of Al-alloys after hot deformation SO HOT DEFORMATION OF ALUMINUM ALLOYS II LA English DT Proceedings Paper CT 2nd Symposium on Hot Deformation of Aluminum Alloys, at the 1998 TMS Fall Meeting CY OCT 11-15, 1998 CL ROSEMONT, IL SP Minerals Met & Mat Soc ID PARTICLE STIMULATED NUCLEATION; LOCAL TEXTURE; DEFORMED ALUMINUM; GROWTH SELECTION; GRAINS; RATES AB The recrystallization textures of Al-alloys can be explained by a growth selection of grains with an approximate 40 degrees<111> orientation relationship out of a limited spectrum of preferentially formed nucleus orientations. Accordingly, recrystallization textures can be modeled by the multiplication of a function f(g)(nucl) describing the probability of nucleation of the various orientations with a function f(g)(grow) representing their growth probability. Whereas the growth probability can be accounted for by a 40 degrees<111> transformation of the rolling texture, the nucleation probability of the respective grains is given by the distribution of potential nucleus orientations, which is known from local texture analysis for the most important nucleation sites in rolled Al-alloys, cube-bands, grain boundaries and second-phase particles. The contributions of each of these nucleation sites are determined according to an approach to calculate the number of nuclei forming at each nucleation site, which is based on microstructural investigations on the evolution of the various nucleation sites during deformation. The paper describes the model for recrystallization texture simulation in Al-alloys and gives examples of recrystallization textures of AA3004 deformed in plane strain compression at a variety of different deformation temperatures and strain rates. C1 Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. RP Engler, O (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Mail Stop K765, Los Alamos, NM 87545 USA. NR 36 TC 0 Z9 0 U1 1 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-412-7 PY 1999 BP 291 EP 302 PG 12 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BM95N UT WOS:000080239000025 ER PT B AU Korzekwa, DA Beaudoin, AJ AF Korzekwa, DA Beaudoin, AJ BE Bieler, TR Lalli, LA MacEwen, SR TI Modeling the effects of friction and geometry on deformation path during hot rolling of aluminum SO HOT DEFORMATION OF ALUMINUM ALLOYS II LA English DT Proceedings Paper CT 2nd Symposium on Hot Deformation of Aluminum Alloys, at the 1998 TMS Fall Meeting CY OCT 11-15, 1998 CL ROSEMONT, IL SP Minerals Met & Mat Soc ID LUBRICATION AB In this work, a parametric study of hot rolling is conducted. The effect of friction model, friction coefficient, roll gap geometry and temperature on the deformation rate field is demonstrated. This parameter space is restricted to a region which is tractable, yet provides considerable variety in the features of non-uniform deformation developed in rolling. The degree and nature of redundant work (shearing) is contrasted for different streamline locations within the bite. Recommendations for the application of material models in analysis of rolling is made with consideration of the simulation predictions. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Korzekwa, DA (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Box 1663,Mail Stop G770, Los Alamos, NM 87545 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-412-7 PY 1999 BP 317 EP 328 PG 12 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BM95N UT WOS:000080239000027 ER PT B AU Vetrano, JS Henager, CH Smith, MT Bruemmer, SM AF Vetrano, JS Henager, CH Smith, MT Bruemmer, SM BE Bieler, TR Lalli, LA MacEwen, SR TI Microstructural development for superplasticity in Al-Mg-Mn alloys SO HOT DEFORMATION OF ALUMINUM ALLOYS II LA English DT Proceedings Paper CT 2nd Symposium on Hot Deformation of Aluminum Alloys, at the 1998 TMS Fall Meeting CY OCT 11-15, 1998 CL ROSEMONT, IL SP Minerals Met & Mat Soc ID GRAIN-REFINEMENT; RECRYSTALLIZATION; ALUMINUM; EVOLUTION; GROWTH AB Thermomechanical processing and alloying additions have been utilized in Al-Mg-Mn alloys to create microstructures suitable for superplastic deformation. Superplasticity typically requires a grain size of less than 10 mu m that is stable against grain growth at temperatures close to the melting point of the material. We have examined the role of Mn, Sc and Zr additions on recrystallization and grain growth during thermomechanical processing and superplastic deformation of cast Al-Mg alloys. Particles containing Mn that formed during solidification were observed to be efficient nuclei for recrystallization but their effectiveness was reduced when Zr was present. This was a result of a shape change in these particles that inhibited them from breaking up and dispersing during hot and cold rolling. Smaller Al6Mn dispersoids, Al3Zr and Al3Sc particles acted to pin grain boundary migration. Their effectiveness was maximized by tailored heat treatments to create an optimum dispersion and particle size. Grain sizes less than 5 mu m could be achieved by conventional cold-rolling and recrystallization treatments, resulting in superplastic elongations of more than 600%. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Vetrano, JS (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 24 TC 0 Z9 0 U1 0 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-412-7 PY 1999 BP 407 EP 418 PG 12 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BM95N UT WOS:000080239000034 ER PT J AU Schmidt, DM George, JS Wood, CC AF Schmidt, DM George, JS Wood, CC TI Bayesian inference applied to the electromagnetic inverse problem SO HUMAN BRAIN MAPPING LA English DT Article DE MRI; MEG; EEG; brain mapping; inverse problem; Monte Carlo; biomagnetic ID HUMAN-BRAIN; LOCALIZATION; CORTEX; MEG; MAGNETOENCEPHALOGRAPHY; POTENTIALS; EEG AB We present a new approach to the electromagnetic inverse problem that explicitly addresses the ambiguity associated with its ill-posed character. Rather than calculating a single "best" solution according to some criterion, our approach produces a large number of Likely solutions that both fit the data and any prior information that is used. Whereas the range of the different Likely results is representative of the ambiguity in the inverse problem even with prior information present, features that are common across a large number of the different solutions can be identified and are associated with a high degree of probability This approach is implemented and quantified within the formalism of Bayesian inference, which combines prior information with that of measurement in a common framework using a single measure. To demonstrate this approach, a general neural activation model is constructed that includes a variable number of extended regions of activation and can incorporate a great deal of prior information on neural current such as information on location, orientation, strength, and spatial smoothness. Taken together, this activation model and the Bayesian inferential approach yield estimates of the probability distributions for the number, location, and extent of active regions. Both simulated MEG data and data from a visual evoked response experiment are used to demonstrate the capabilities of this approach. Published 1999 Wiley-Liss, Inc. C1 Univ Calif Los Alamos Natl Lab, Biophys Grp, Los Alamos, NM 87545 USA. RP Schmidt, DM (reprint author), Univ Calif Los Alamos Natl Lab, Biophys Grp, MS-D454, Los Alamos, NM 87545 USA. FU NEI NIH HHS [EY0861003]; NIDA NIH HHS [DA/MH09972] NR 34 TC 88 Z9 88 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 1065-9471 J9 HUM BRAIN MAPP JI Hum. Brain Mapp. PY 1999 VL 7 IS 3 BP 195 EP 212 DI 10.1002/(SICI)1097-0193(1999)7:3<195::AID-HBM4>3.0.CO;2-F PG 18 WC Neurosciences; Neuroimaging; Radiology, Nuclear Medicine & Medical Imaging SC Neurosciences & Neurology; Radiology, Nuclear Medicine & Medical Imaging GA 180EJ UT WOS:000079372400004 PM 10194619 ER PT J AU Arroyo, CM Schafer, RJ Kurt, EM Broomfield, CA Carmichael, AJ AF Arroyo, CM Schafer, RJ Kurt, EM Broomfield, CA Carmichael, AJ TI Response of normal human keratinocytes to sulfur mustard (HD): cytokine release using a non-enzymatic detachment procedure SO HUMAN & EXPERIMENTAL TOXICOLOGY LA English DT Article DE vesicant agents; keratinocytes; sulfur mustard; ELISA; human keratinocytes; IL-1 beta; IL-6 ID TUMOR-NECROSIS-FACTOR; SKIN; PROLIFERATION; INTERLEUKIN-8; INFLAMMATION; CELLS; IL-8 AB Cytokines play a major role in both acute and chronic inflammatory processes, including those produced by sulfur mustard (HD). This study describes responses of normal human epidermal keratinocyte (NHEK) cells to 2,2'-dichlorodiethyl sulfide, sulfur mustard (HD), defined by interleukin-l beta (IL-1 beta), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-alpha (TNF-alpha) release. A new method for detaching cell to cell adhesion between keratinocytes has been applied. This method permits the characterization of endogenous fluid from cellular content that could be applied for the development of therapeutic intervention. NHEK (typical average cell density 4.4 x 10(6) cells/mL) were exposed to HD (100 and 300 mu M) in keratinocyte growth medium (KGM) for 24 h at 37 degrees C in humidified air. Commercially available enzyme-linked immunosorbent assay (ELISA) kits were used to measure the cytokine release in NHEK during exposure to 100 and 300 mu M of HD. Exposure to 100 mu M HD increased release of cytokines. IL-1 beta (exposed: 1.41x10(-5)pg/cell +/- 1.60 x 10 (6) pg/cell: control 7.10 x 10 (6) pg cell +/- 1.20 x 10 (6) pg/cell), TNF-alpha (exposed: 1.06 x 10 (6) pg/cell +/- 7.3 x 10 (7) pg/cell; control: 4.04 x 10 (6) +/- 2.80 x 10 (7) pg/cell) and IL-8 (exposed: 3.71 x 10(-5) pg/ cell +/- 3.26 x 10 (6) pg/cell; control: 2.99 x 10 (6) pg/cell +/- 8.80 x 10 (7) pg/cell) were significantly enhanced when NHEK cells were detached from culture flasks by non-enzymatic procedures. Cell suspensions of NHEK released low amounts of IL-6 when exposed to 100 mu M for 24 h (exposed: 1.47 x 10(-6) +/- 1.60 x 10 (7) pg/cell; control: 1.28 x 10 (6) +/- 8.40 x 10 (8) pg/cell). However, cell suspensions of NHEK increased levels of IL-6 after exposure to 300 mu M HD (4.67 x 10 (-5) pg/cell +/- 3.90 x 10 (6) pg/cell; control: 3.99 x 10(-6) pg/cell +/- 5.50 x 10 (7) pg/cell). The amount of IL-8 and TNF-alpha present in cell suspensions increased up to 59-fold and fourfold, respectively, above control levels when NHEK cells were exposed to 300 mu M HD. Exposure of NHEK to 300 mu M HD had a highly variable effect on the release of IL-1 beta, where sometimes the secretion of IL-1 beta increased above baseline level and other times decreased in cell suspensions. Supernatants were collected from cell culture flasks 24 h after exposure of 100 and 300 mu M and significantly increased levels of IL-6 were observed. IL-6 was released in a concentration-dependent manner, 3.6-fold up to 8.4-fold, respectively, in supernatant. These proinflammatory mediators IL-1 beta, IL-8, TNF-alpha and IL-6 may play an important role in HD injury. The present findings suggest that cytokine changes detected could be used as potential biomarkers of cutaneous vesicant injury. C1 USA, Med Res Inst Chem Def, MCMR, UV,DA, Aberdeen Proving Ground, MD 21010 USA. Oak Ridge Inst Sci & Educ Res, Participat Program, Oak Ridge, TN USA. RP Arroyo, CM (reprint author), USA, Med Res Inst Chem Def, MCMR, UV,DA, 3100 Ricketts Point Rd, Aberdeen Proving Ground, MD 21010 USA. NR 27 TC 39 Z9 42 U1 0 U2 0 PU STOCKTON PRESS PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 0144-5952 J9 HUM EXP TOXICOL JI Hum. Exp. Toxicol. PD JAN PY 1999 VL 18 IS 1 BP 1 EP 11 DI 10.1191/096032799678839329 PG 11 WC Toxicology SC Toxicology GA 163YP UT WOS:000078434700001 PM 10025362 ER PT J AU Cleaver, JE Thompson, LH Richardson, AS States, JC AF Cleaver, JE Thompson, LH Richardson, AS States, JC TI A summary of mutations in the UV-sensitive disorders: Xeroderma pigmentosum, Cockayne syndrome, and trichothiodystrophy SO HUMAN MUTATION LA English DT Review DE xeroderma pigmentosum; Cockayne syndrome; trichothiodystrophy; DNA repair; mutation ID NUCLEOTIDE EXCISION-REPAIR; REPLICATION PROTEIN-A; TRANSCRIPTION-COUPLED REPAIR; DNA-BINDING PROTEIN; RNA-POLYMERASE-II; DAMAGE RECOGNITION PROTEIN; COMPLEMENTATION GROUP-D; GROUP-C PROTEIN; XPAC GENE; XPD GENE AB The human diseases xeroderma pigmentosum, Cockayne syndrome, and trichothiodystrophy are caused by mutations in a set of interacting gene products, which carry out the process of nucleotide excision repair. The majority of the genes have now been cloned and many mutations in the genes identified. The relationships between the distribution of mutations in the genes and the clinical presentations can be used for diagnosis and for understanding the functions and the modes of interaction among the gene products. The summary presented here represents currently known mutations that can be used as the basis for future studies of the structure, function, and biochemical properties of the proteins involved in this set of complex disorders, and may allow determination of the critical sites for mutations leading to different clinical manifestations. The summary indicates where more data are needed for some complementation groups that have few reported mutations, and for the groups for which the gene(s) are not yet cloned. These include the Xeroderma pigmentosum (XP) variant, the trichothiodystrophy group A (TTDA), and ultraviolet sensitive syndrome (UVs) groups. We also recommend that the XP group E should be defined explicitly through molecular terms, because assignment by complementation in culture has been difficult. XP-E by this definition contains only those cell lines and patients that have mutations in the small subunit, DDB2, of a damage specific DNA binding protein. Hum Mutat 14:9-22, 1999. (C) 1999 Wiley-Liss, Inc. C1 Univ Calif San Francisco, Ctr Canc, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Dermatol, San Francisco, CA 94143 USA. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA USA. Wayne State Univ, Inst Chem Toxicol, Detroit, MI 48201 USA. RP Cleaver, JE (reprint author), Univ Calif San Francisco, Ctr Canc, San Francisco, CA 94143 USA. RI States, J./H-4246-2011 FU NCRR NIH HHS [R25 RR12242]; NIEHS NIH HHS [ES08061, R01 ES06460] NR 111 TC 139 Z9 151 U1 1 U2 13 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1059-7794 J9 HUM MUTAT JI Hum. Mutat. PY 1999 VL 14 IS 1 BP 9 EP 22 DI 10.1002/(SICI)1098-1004(1999)14:1<9::AID-HUMU2>3.0.CO;2-6 PG 14 WC Genetics & Heredity SC Genetics & Heredity GA 212FR UT WOS:000081207100002 PM 10447254 ER PT J AU Rabehl, RJ Mitchell, JW Beckman, WA AF Rabehl, RJ Mitchell, JW Beckman, WA TI Parameter estimation and the use of catalog data in modeling heat exchangers and coils SO HVAC&R RESEARCH LA English DT Article AB This paper presents a technique for developing models that can accurately replicate equipment performance of heat exchangers and coils. The technique employs mechanistic relations with unspecified parameters as the basis for the model relations. Catalog information is then used to estimate the best value of the parameters. Only a few geometric specifications are required and only a small number of parameters need to be fit. The technique is robust and accurately replicates catalog information over the entire operating range. Major advantages are that the use of mechanistic relations allows extension to different heat transfer fluids, different temperature ranges, and different temperature levels. The performance of the models developed with this technique is compared to that using the models of the ASHRAE HVA C 2 Toolkit (Brandemuehl 1992) and the historical ASHRAE approach (Stoecker 1975). The technique is illustrated for the heat transfer and pressure drop characteristics of a specific set of chilled water cooling coils. Results for a number of different heat exchanger types from different manufacturers such as shell-in-tube heat exchangers, heating and cooling coils, and direct expansion coils are also reported. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Wisconsin, Madison, WI USA. RP Rabehl, RJ (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 10 TC 12 Z9 12 U1 0 U2 0 PU AMER SOC HEATING REFRIGERATING AIR-CONDITIONING ENG, INC, PI ATLANTA PA 1791 TULLIE CIRCLE NE, ATLANTA, GA 30329 USA SN 1078-9669 J9 HVAC&R RES JI HVAC&R Res. PD JAN PY 1999 VL 5 IS 1 BP 3 EP 17 DI 10.1080/10789669.1999.10391220 PG 15 WC Thermodynamics; Construction & Building Technology; Engineering, Mechanical SC Thermodynamics; Construction & Building Technology; Engineering GA 165BX UT WOS:000078500000002 ER PT B AU van Breugel, W De Breuck, C Stanford, A Rottgering, H Miley, G Stern, D Minniti, D Carilli, C AF van Breugel, W De Breuck, C Stanford, A Rottgering, H Miley, G Stern, D Minniti, D Carilli, C BE Bunker, AJ VanBreugel, WJM TI Ultra-steep spectrum radio galaxies at Hy redshifts SO HY-REDSHIFT UNIVERSE: GALAXY FORMATION AND EVOLUTION AT HIGH REDSHIFT SE Astronomical Society of the Pacific Conference Series LA English DT Proceedings Paper CT International Meeting on the Hy-Redshift Universe - Galaxy Formation and Evolution at High Redshift CY JUN 21-24, 1999 CL UNIV CALIF, BERKELEY, CA SP Univ Calif HO UNIV CALIF ID LYMAN-ALPHA EMISSION; VLA-SKY-SURVEY; QUASARS; SAMPLE; Z=4.25; MHZ AB Radio sources have traditionally provided convenient beacons for probing the early Universe. Hy Spinrad was among the first of the tenacious breed of observers who would attempt to obtain optical identifications and spect:ra of the faintest possible 'radio galaxies' to investigate the formation and evolution of galaxies at hy redshift. Modern telescopes and instruments have made these tasks much simpler, although not easy, and here we summarize the current status of our hunts for by redshift radio galaxies (HyZRGs) using radio spectral and near-IR, selection. C1 Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. EM wil@igpp.llnl.gov; adam@igpp.llnl.gov; dan@slothrop.berkeley.edu NR 50 TC 2 Z9 2 U1 0 U2 1 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-019-6 J9 ASTR SOC P PY 1999 VL 193 BP 44 EP 54 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP85L UT WOS:000086435200005 ER PT S AU McCluskey, MD Haller, EE AF McCluskey, MD Haller, EE BE Nickel, NH TI Hydrogen in III-V and II-VI semiconductors SO HYDROGEN IN SEMICONDUCTORS II SE Semiconductors and Semimetals LA English DT Review ID LOCAL VIBRATIONAL-MODES; CHEMICAL-VAPOR-DEPOSITION; MOLECULAR-BEAM EPITAXY; INTERSTITIAL HYDROGEN; GALLIUM-ARSENIDE; ELECTRICAL-PROPERTIES; ACCEPTOR-HYDROGEN; SEMIINSULATING INP; SHALLOW IMPURITIES; ALXGA1-XAS ALLOYS C1 Xerox Corp, Palo Alto Res Ctr, Palo Alto, CA 94304 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Washington State Univ, Dept Phys, Pullman, WA 99164 USA. NR 124 TC 4 Z9 4 U1 0 U2 2 PU ELSEVIER ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 0080-8784 BN 0-12-752170-4 J9 SEMICONDUCT SEMIMET JI Semicond. Sdemimet. PY 1999 VL 61 BP 373 EP 440 PG 68 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BN22L UT WOS:000081151200009 ER PT B AU Hammack, RW Dijkman, H AF Hammack, RW Dijkman, H BE Young, SK Dreisinger, DB Hackl, RP Dixon, DG TI The application of bacterial sulfate reduction treatment to severely contaminated mine waters: results of three years of pilot plant testing SO HYDROMETALLURGY OF COPPER LA English DT Proceedings Paper CT 4th International Conference of the COPPER 99/COBRE 99 CY OCT 10-13, 1999 CL PHOENIX, AZ SP Chilean Inst Min Engineers, Met Soc Canadian Inst Min, Met & Petr, Minerals Met & Mat Soc, Soc Min, Met & Explorat AB Results for the treatment of a problematic mining wastewater using bacterial sulfate reduction (BSR) are presented. Specifically, a BSR pilot treatment plant (250 L per day) was used to treat Berkeley Pit simulant to discharge standards with the selective recovery of separate Cu- and Zn-sulfide concentrates. Concentrates recovered in these tests contained greater than 50 % of the target metal and met specifications for sale to existing smelters. The biological component of the treatment was found to be surprisingly robust. Scaling and solid/liquid separation problems were encountered but considered normal for sulfide treatment. For Berkeley Pit water, capital costs for BSR treatment was found to be comparable to high-density sludge lime treatment, The value received from the sale of recovered copper and zinc concentrates paid for all the operating costs. C1 US DOE, Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. RP Hammack, RW (reprint author), US DOE, Fed Energy Technol Ctr, POB 10940, Pittsburgh, PA 15236 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-438-0 PY 1999 BP 97 EP 111 PG 15 WC Metallurgy & Metallurgical Engineering; Mining & Mineral Processing SC Metallurgy & Metallurgical Engineering; Mining & Mineral Processing GA BP62T UT WOS:000085715100008 ER PT J AU Lipkin, HJ AF Lipkin, HJ TI Mossbauer sum rules for use with synchrotron sources SO HYPERFINE INTERACTIONS LA English DT Article ID NUCLEAR BRAGG SCATTERING; RESONANT SCATTERING; RADIATION; RESOLUTION AB The availability of tunable synchrotron radiation sources with millivolt resolution has opened new prospects for exploring dynamics of complex systems with Mossbauer spectroscopy. Early Mossbauer treatments and moment sum rules are extended to treat inelastic excitations measured in synchrotron experiments, with emphasis on the unique new conditions absent in neutron scattering and arising in resonance scattering: prompt absorption, delayed emission, recoil-free transitions and coherent forward scattering. The first moment sum rule normalizes the inelastic spectrum. New sum rules obtained for higher moments include the third moment proportional to the second derivative of the potential acting on the Mossbauer nucleus and independent of temperature in the the harmonic approximation. C1 Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Lipkin, HJ (reprint author), Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. NR 29 TC 5 Z9 5 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 123 IS 1-8 BP 349 EP 366 DI 10.1023/A:1017019822825 PG 18 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 288VG UT WOS:000085584700010 ER PT J AU Sturhahn, W Kohn, VG AF Sturhahn, W Kohn, VG TI Theoretical aspects of incoherent nuclear resonant scattering SO HYPERFINE INTERACTIONS LA English DT Article ID SYNCHROTRON-RADIATION AB The influence of nonrotational atomic motion on the scattering of X-rays by nuclei with sharp resonances is investigated. Two incoherent scattering channels, nuclear resonant fluorescence and nuclear resonant absorption followed by conversion electron emission and atomic fluorescence, are studied in detail. Time dependence and cross sections for these processes are given. In both cases, the cross section is proportional to the self-intermediate scattering function of the resonant isotope. The influence of other X-ray scattering processes on incoherent nuclear resonant scattering is discussed. We find that incoherent scattering channels dominate in off-resonance excitations. Self-intermediate scattering functions for the ideal gas and the harmonic lattice are calculated. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Russian Res Ctr, Kurchatov Inst, Moscow 123182, Russia. RP Sturhahn, W (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. NR 36 TC 57 Z9 57 U1 1 U2 2 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 123 IS 1-8 BP 367 EP 399 DI 10.1023/A:1017071806895 PG 33 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 288VG UT WOS:000085584700011 ER PT J AU Chumakov, AI Niesen, L Nagy, DL Alp, EE AF Chumakov, AI Niesen, L Nagy, DL Alp, EE TI Nuclear resonant scattering of synchrotron radiation by multilayer structures SO HYPERFINE INTERACTIONS LA English DT Article ID INCIDENCE ANTIREFLECTION FILMS; DIFFRACTION EXPERIMENTS; MOSSBAUER; LAYERS; FE; EXCITATIONS; BEHAVIOR; RAYS AB Multilayer structures form a particular class of samples employed in nuclear resonant scattering of synchrotron radiation. Their specific properties lead to unusual energy and time characteristics of nuclear resonant scattering, which differ much from those of single crystals. The analysis of these distinctions is presented. Several approaches to achieve pure nuclear reflections with multilayers are discussed. Finally, we review the studies of multilayer structures with nuclear resonant scattering of synchrotron radiation. C1 European Synchrotron Radiat Facil, F-38043 Grenoble, France. Russian Res Ctr, Kurchatov Inst, Moscow 123182, Russia. Univ Groningen, Ctr Mat Sci, NL-9747 AG Groningen, Netherlands. KFKI Res Inst Particle & Nucl Phys, H-1525 Budapest, Hungary. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Chumakov, AI (reprint author), European Synchrotron Radiat Facil, BP 220, F-38043 Grenoble, France. OI Nagy, Denes Lajos/0000-0002-6790-9505 NR 51 TC 29 Z9 30 U1 1 U2 1 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 123 IS 1-8 BP 427 EP 454 DI 10.1023/A:1017028024642 PG 28 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 288VG UT WOS:000085584700013 ER PT J AU Leupold, O Chumakov, AI Alp, EE Sturhahn, W Baron, AQR AF Leupold, O Chumakov, AI Alp, EE Sturhahn, W Baron, AQR TI Noniron isotopes SO HYPERFINE INTERACTIONS LA English DT Article ID NUCLEAR RESONANT SCATTERING; SYNCHROTRON-RADIATION; TIME RESOLUTION; X-RAYS; EXCITATION; DETECTOR; SN-119; TA-181; EU-151 AB This article reports on experimental developments and first results for Mossbauer isotopes other than Fe-57. We will restrict ourselves to basic features of the resonances of Tm-169, Sn-119, Kr-83, Ta-181, and Eu-151 and want to point out remarkable differences in instrumentation - like monochromator design - compared with Fe-57. Some applications can be found in other sections of this issue. C1 Univ Hamburg, Inst Expt Phys 2, D-22761 Hamburg, Germany. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. SPring 8, Mikazuki, Hyogo 6795198, Japan. RP Leupold, O (reprint author), European Synchrotron Radiat Facil, BP 220, F-38043 Grenoble, France. NR 50 TC 26 Z9 26 U1 0 U2 4 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 123 IS 1-8 BP 611 EP 631 DI 10.1023/A:1017000713255 PG 21 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 288VG UT WOS:000085584700021 ER PT J AU Siddons, DP Bergmann, U Hastings, JB AF Siddons, DP Bergmann, U Hastings, JB TI Polarization effects in resonant nuclear scattering SO HYPERFINE INTERACTIONS LA English DT Article ID TIME-DEPENDENT POLARIZATION; SYNCHROTRON-RADIATION; MOSSBAUER EXPERIMENTS; BRAGG-DIFFRACTION; QUANTUM BEATS; X-RAYS; IRON AB Polarization phenomena are present in every radiative transition, whether it is of atomic or nuclear origin. Nuclear resonant scattering of synchrotron radiation is an ideal technique for their study because (a) the probing radiation is in a well characterized polarization state, in most cases linear, (b) the scattered radiation can be efficiently analyzed with polarization filters, and (c) synchrotron pulses are very short compared to the lifetime of a nuclear resonance, resulting in a clean signal. In the following article we describe experimental and theoretical studies of the 14.4 keV Mossbauer resonance of Fe-57 and its transitions with linear and circular polarization. After introducing the required instrumentation a formalism to calculate time dependent polarization phenomena is derived. With the help of different scattering geometries we illustrate various aspects, such as polarization mixing and selective excitation of subsets of the resonance. Perhaps the most fascinating example is the Faraday geometry where the E-vector rotates several 360 degrees turns during the lifetime of the resonant scattering. A comparison of this phenomenon with the optical Faraday effect is given. New powerful synchrotron radiation sources will enable researchers to exploit polarization phenomena in nuclear resonant scattering to detect subtle changes in physically and chemically relevant systems. C1 Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Siddons, DP (reprint author), Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. NR 52 TC 10 Z9 10 U1 0 U2 1 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 123 IS 1-8 BP 681 EP 719 DI 10.1023/A:1017096512347 PG 39 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 288VG UT WOS:000085584700024 ER PT J AU Chumakov, AI Sturhahn, W AF Chumakov, AI Sturhahn, W TI Experimental aspects of inelastic nuclear resonance scattering SO HYPERFINE INTERACTIONS LA English DT Article ID X-RAY-SCATTERING; MEV ENERGY RESOLUTION; SYNCHROTRON-RADIATION; TEMPERATURE-DEPENDENCE; FE-57; ABSORPTION; EXCITATION; DYNAMICS; PHONONS; CRYSTAL AB We present an introduction to the technique of inelastic nuclear scattering. The details of experimental setup, instrumentation, and measuring procedure are discussed. The typical appearance of experimental results and a brief description of data treatment methods are illustrated by examples of recent studies. Finally, the scope of information on lattice dynamics that is accessible with inelastic nuclear scattering is outlined. C1 European Synchrotron Radiat Facil, F-38043 Grenoble, France. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Chumakov, AI (reprint author), European Synchrotron Radiat Facil, BP 220, F-38043 Grenoble, France. NR 50 TC 96 Z9 97 U1 1 U2 7 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 123 IS 1-8 BP 781 EP 808 DI 10.1023/A:1017052730094 PG 28 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 288VG UT WOS:000085584700027 ER PT J AU Sturhahn, W Chumakov, A AF Sturhahn, W Chumakov, A TI Lamb-Mossbauer factor and second-order Doppler shift from inelastic nuclear resonant absorption SO HYPERFINE INTERACTIONS LA English DT Article ID SYNCHROTRON-RADIATION; X-RAYS; TEMPERATURE-DEPENDENCE; SCATTERING; ALPHA-FE-57; RESOLUTION; SN-119; STATES; FE-57; IRON AB The derivation of Lamb-Mossbauer factors and second-order Doppler shifts from data that are measured by inelastic nuclear resonant absorption of synchroton radiation is demonstrated. This approach offers a viable alternative to procedures that are based on elastic absorption and scattering techniques. The sources of error are evaluated, and a selection of examples is provided. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. European Synchrotron Radiat Facil, F-38043 Grenoble, France. RP Sturhahn, W (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. NR 40 TC 24 Z9 24 U1 1 U2 7 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 123 IS 1-8 BP 809 EP 824 DI 10.1023/A:1017060931911 PG 16 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 288VG UT WOS:000085584700028 ER PT J AU Keune, W Sturhahn, W AF Keune, W Sturhahn, W TI Inelastic nuclear resonant absorption of synchrotron radiation in thin films and multilayers SO HYPERFINE INTERACTIONS LA English DT Article ID TB-FE FILMS; STRUCTURAL ANISOTROPY; METALLIC SUPERLATTICES; SCATTERING; INTERFACE; PHONONS; DEPENDENCE; CEMS AB Inelastic nuclear resonant absorption of synchrotron radiation is an efficient and unique method for the direct measurement of vibrational density of states (VDOS) of thin films and interfaces that contain Mossbauer isotopes. This is demonstrated for the Fe-57 nuclear resonance in the case of amorphous and crystalline Tb-Fe alloy thin films and buried Fe/Cr interfaces in epitaxial alpha-Fe(0 0 1)/Cr(0 0 1) superlattices. C1 Univ Duisburg Gesamthsch, Lab Angew Phys, D-47048 Duisburg, Germany. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Keune, W (reprint author), Univ Duisburg Gesamthsch, Lab Angew Phys, D-47048 Duisburg, Germany. NR 39 TC 20 Z9 20 U1 0 U2 0 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 123 IS 1-8 BP 847 EP 861 DI 10.1023/A:1017008915073 PG 15 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 288VG UT WOS:000085584700031 ER PT J AU Pollmann, J Ruter, HD Gerdau, E AF Pollmann, J Ruter, HD Gerdau, E TI The temperature dependence of the hyperfine parameters of YIG below the Curie point SO HYPERFINE INTERACTIONS LA English DT Article DE Mossbauer spectroscopy; yttrium iron garnet ID LINE-SHAPE; DIFFRACTION AB The temperature dependence of the hyperfine parameters of the Fe-57 nuclei in yttrium iron garnet Y3Fe5O12 (YIG) between room temperature and the Curie point was studied by means of conventional Mossbauer transmission spectroscopy. The critical exponent beta, which describes the temperature dependence of the magnetic hyperfine field of 57Fe in YIG, was found to be 0.29(1) and 0.33(1) in the [a]- and (d)-sublattice, respectively. In the temperature region just below the Curie point relaxation of the internal hyperfine fields could be observed. The phase transition at the Curie point shows a distinct dependence on the grain size in the sample. C1 Univ Hamburg, Inst Expt Phys 2, D-22761 Hamburg, Germany. RP Pollmann, J (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. NR 19 TC 5 Z9 5 U1 0 U2 4 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 122 IS 3-4 BP 353 EP 364 DI 10.1023/A:1012699118282 PG 12 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 258XG UT WOS:000083864500013 ER PT J AU Sato, K Miyake, T Morishita, A Matsuta, K Minamisono, T Tanigaki, M Takeda, S Mihara, M Fukuda, M Nojiri, Y Minamisono, K Fukao, T Matsumoto, Y Ohtsubo, T Fukuda, S Momota, S Yoshida, K Ozawa, A Kobayashi, T Tanihata, I Sagawa, H Kitagawa, H Krebs, GF Alonso, JR Symons, TJM AF Sato, K Miyake, T Morishita, A Matsuta, K Minamisono, T Tanigaki, M Takeda, S Mihara, M Fukuda, M Nojiri, Y Minamisono, K Fukao, T Matsumoto, Y Ohtsubo, T Fukuda, S Momota, S Yoshida, K Ozawa, A Kobayashi, T Tanihata, I Sagawa, H Kitagawa, H Krebs, GF Alonso, JR Symons, TJM TI Hyperfine interactions of O-19 in TiO2 and quadrupole moments of O-13,O-19 SO HYPERFINE INTERACTIONS LA English DT Article; Proceedings Paper CT 11th International Conference on Hyperfine Interactions CY AUG 23-28, 1998 CL DURBAN, SOUTH AFRICA ID PROTON HALO AB The electric quadrupole interaction of O-19(I-pi = (5/2)(+), T-1/2 = 27.0 s) in TiO2 single crystal was studied in detail by means of the beta-NQR to determine the electric quadrupole moments Q of short-lived beta-emitting nuclei O-19 and O-13(I-pi = (3/2)(-) T-1/2 = 8.6 ms). Two implantation sites were found for the implanted O nucleus and the quadrupole coupling constants of O-19 at these sites were determined. We observed FT-NMR of the enriched stable isotope O-17 in TiO2 and obtained the electric field gradient (EFG) at the oxygen substitutional site. With this knowledge, we have determined Q(O-13) = 11.0 +/- 1.3 mb and Q(O-19) = 3.7 +/- 0.4 mb. The present results are compared with the theoretical values calculated by the shell model code, OXBASH and by the Hartree-Fock calculation with the realistic potential. C1 Osaka Univ, Grad Sch Sci, Dept Phys, Osaka 5600043, Japan. Tohoku Univ, Cyclotron & Radio Isotope Ctr, Sendai, Miyagi 98077, Japan. Gunma Univ, Fac Engn, Kiryu, Gumma 376, Japan. Kochi Univ Technol, Kochi 782, Japan. Niigata Univ, Fac Sci, Dept Phys, Niigata 95021, Japan. Energy Res Ctr, Fukui 914, Japan. RIKEN, Wako, Saitama 35101, Japan. Univ Aizu, Ctr Math Sci, Fukushima 965, Japan. Tokyo Metropolitan Univ, Fac Sci, Hachioji, Tokyo 19203, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Sato, K (reprint author), Osaka Univ, Grad Sch Sci, Dept Phys, Osaka 5600043, Japan. NR 8 TC 1 Z9 1 U1 1 U2 3 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 120 IS 1-8 BP 661 EP 665 DI 10.1023/A:1017031908770 PG 5 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 236UP UT WOS:000082617800111 ER PT J AU Matsuta, K Onishi, T Fukuda, M Minamisono, T Akai, H Sasaki, M Yamaguchi, T Miyake, T Sato, K Minamisono, K Ohsumi, F Muramoto, Y Oui, S Ha, C Tanaka, K Kidera, K Morishita, A Kitagawa, A Torikoshi, M Kanazawa, M Nishio, T Koda, S Ohtsubo, T Fukuda, S Nojiri, Y Momota, S Ozawa, A Yoshida, K Suzuki, T Kobayashi, T Tanihata, I Hanna, SS Alonso, JR Krebs, GF Symons, TJM AF Matsuta, K Onishi, T Fukuda, M Minamisono, T Akai, H Sasaki, M Yamaguchi, T Miyake, T Sato, K Minamisono, K Ohsumi, F Muramoto, Y Oui, S Ha, C Tanaka, K Kidera, K Morishita, A Kitagawa, A Torikoshi, M Kanazawa, M Nishio, T Koda, S Ohtsubo, T Fukuda, S Nojiri, Y Momota, S Ozawa, A Yoshida, K Suzuki, T Kobayashi, T Tanihata, I Hanna, SS Alonso, JR Krebs, GF Symons, TJM TI Electromagnetic moments of short lived beta emitters F-21, Mg-23, Si-27 and Ca-39 SO HYPERFINE INTERACTIONS LA English DT Article; Proceedings Paper CT 11th International Conference on Hyperfine Interactions CY AUG 23-28, 1998 CL DURBAN, SOUTH AFRICA AB The beta-NMR spectra of F-21, Mg-23, Si-27 and Ca-39 which were produced in heavy ion collisions and implanted in various crystals have been observed. The magnetic moments of F-21 and Si-27 were determined to be \mu(F-21)\ = 3.9194 +/- 0.0012 mu(N) and \mu(Si-27)\ = 0.8653 +/- 0.0003 mu(N), respectively. The electric quadrupole coupling constants were determined for the first time to be \eqQ(F-21 in MgF2)/h\ = 9.94 +/- 0.09 MHz, \eqQ(Mg-23 in MgF2)/h\ = 1.96 +/- 0.06 MHz, \eqQ(Si-27 in Al2O3)/h\ = 1.90 +/- 0.12 MHz, \eqQ(Ca-39 in CaCO3)/h\ = 0.60 +/- 0.04 MHz. From the present eqQ/h, the Q moments were deduced as \Q(F-21)\ = 110 +/- 22 mb, \Q(Mg-23)\ = 114 +/- 3 mb, \Q(Si-27)\ = 60 +/- 13 mb and \Q(Ca-39)\ = 36 +/- 7 mb. The present data were compared with the theoretical values obtained by the OXBASH shell model code. C1 Osaka Univ, Dept Phys, Toyonaka, Osaka 560, Japan. NIRS, HIMAC, Inage Ku, Chiba 263, Japan. Niigata Univ, Fac Sci, Niigata 95021, Japan. Energy Ctr, Fukui 914, Japan. Kochi Univ Technol, Kochi 782, Japan. RIKEN, Wako, Saitama 35101, Japan. Stanford Univ, Stanford, CA 94305 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Matsuta, K (reprint author), Osaka Univ, Dept Phys, Toyonaka, Osaka 560, Japan. NR 15 TC 7 Z9 7 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 120 IS 1-8 BP 673 EP 677 DI 10.1023/A:1017036009679 PG 5 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 236UP UT WOS:000082617800113 ER PT J AU Matsuta, K Onishi, T Fukuda, M Minamisono, T Mihara, M Sasaki, M Yamaguchi, T Miyake, T Sato, K Minamisono, K Ohsumi, F Muramoto, Y Oui, S Ha, C Tanaka, K Kidera, K Morishita, A Tsubota, T Sumikama, T Kitagawa, A Torikoshi, M Kanazawa, M Nishio, T Koda, S Ohtsubo, T Fukuda, S Nojiri, Y Momota, S Ozawa, A Yoshida, K Suzuki, T Kobayashi, T Tanihata, I Hanna, SS Alonso, JR Krebs, GF Symons, TJM AF Matsuta, K Onishi, T Fukuda, M Minamisono, T Mihara, M Sasaki, M Yamaguchi, T Miyake, T Sato, K Minamisono, K Ohsumi, F Muramoto, Y Oui, S Ha, C Tanaka, K Kidera, K Morishita, A Tsubota, T Sumikama, T Kitagawa, A Torikoshi, M Kanazawa, M Nishio, T Koda, S Ohtsubo, T Fukuda, S Nojiri, Y Momota, S Ozawa, A Yoshida, K Suzuki, T Kobayashi, T Tanihata, I Hanna, SS Alonso, JR Krebs, GF Symons, TJM TI Spin polarization of beta-emitting fragments in high energy heavy ions on Be collisions SO HYPERFINE INTERACTIONS LA English DT Article; Proceedings Paper CT 11th International Conference on Hyperfine Interactions CY AUG 23-28, 1998 CL DURBAN, SOUTH AFRICA AB The degrees of nuclear spin polarization of B-8,B-12, C-9, N-12, O-13, F-20,F-21, Mg-23, Si-27 and Ca-39 produced in the high energy C-12,C-13, O-16, Ne-22, Mg-24, Si-28 and Ca-40 ions on Be collisions have been measured systematically, for the technical developments of the nuclear moment studies as well as the hyperfine interaction studies by means of beta-NMR technique. The fragment momentum dependences were well reproduced by the simple kinematical model. Incident energy dependence and the mass dependence as well as the reaction angle dependences were qualitatively explained by the mixing of the near and far side collisions. C1 Osaka Univ, Dept Phys, Toyonaka, Osaka 560, Japan. NIRS, HIMAC, Chiba 263, Japan. Niigata Univ, Fac Sci, Niigata 95021, Japan. Energy Ctr Wakasa Bay, Fukui 914, Japan. Kochi Univ Technol, Kochi 782, Japan. RIKEN, Wako, Saitama 35101, Japan. Stanford Univ, Stanford, CA 94305 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Matsuta, K (reprint author), Osaka Univ, Dept Phys, Toyonaka, Osaka 560, Japan. NR 7 TC 3 Z9 3 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 120 IS 1-8 BP 713 EP 717 DI 10.1023/A:1017000429243 PG 5 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 236UP UT WOS:000082617800120 ER PT J AU Matsuta, K Minamisono, T Tanigaki, M Onishi, T Fukuda, M Mihara, M Akai, H Sasaki, M Yamaguchi, T Miyake, T Sato, K Minamisono, K Ha, C Tanaka, K Kidera, K Morishita, A Kaminaka, S Tsubota, T Sumikama, T Kitagawa, A Torikoshi, M Kanazawa, M Nishio, T Koda, S Ohtsubo, T Nojiri, Y Momota, S Hanna, SS Alonso, JR Krebs, GF Symons, TJM AF Matsuta, K Minamisono, T Tanigaki, M Onishi, T Fukuda, M Mihara, M Akai, H Sasaki, M Yamaguchi, T Miyake, T Sato, K Minamisono, K Ha, C Tanaka, K Kidera, K Morishita, A Kaminaka, S Tsubota, T Sumikama, T Kitagawa, A Torikoshi, M Kanazawa, M Nishio, T Koda, S Ohtsubo, T Nojiri, Y Momota, S Hanna, SS Alonso, JR Krebs, GF Symons, TJM TI Knight shifts for short-lived beta emitters in Pt SO HYPERFINE INTERACTIONS LA English DT Article; Proceedings Paper CT 11th International Conference on Hyperfine Interactions CY AUG 23-28, 1998 CL DURBAN, SOUTH AFRICA AB The Knight shifts K for short-lived beta emitters N-12 and Si-27 implanted in Pt have been measured by means of beta-NMR technique. The results were K(N-12 in Pt) = +(5.8 +/- 2.1) X 10(-4) and K(Si-27 in Pt) = +(1.4 +/- 0.8) X 10(-3). The spin-lattice relaxation time T-1 was measured for N-12 in Pt. The result was T-1(N-12 in Pt, T = 300 K) = 66 +/- 8 ms, thus, T1T = 20 +/- 2 Ks. The present Knight shifts are in good agreement with the KKR band structure calculation with local lattice relaxation determined theoretically. C1 Osaka Univ, Dept Phys, Toyonaka, Osaka 560, Japan. Tohoku Univ, Radio Isotope Ctr, Sendai, Miyagi 98077, Japan. NIRS, HIMAC, Chiba 263, Japan. Niigata Univ, Fac Sci, Niigata 95021, Japan. Kochi Univ Technol, Kochi 782, Japan. Stanford Univ, Stanford, CA 94305 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Matsuta, K (reprint author), Osaka Univ, Dept Phys, Toyonaka, Osaka 560, Japan. NR 4 TC 9 Z9 9 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 120 IS 1-8 BP 719 EP 723 DI 10.1023/A:1017052413313 PG 5 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 236UP UT WOS:000082617800121 ER PT J AU Maev, EM Balin, DV Case, T Crowe, KM Del Rosso, A Ganzha, VA Hartmann, FJ Kozlov, SM Lauss, B Maev, OE Muhlbauer, M Mulhauser, F Petitjean, C Petrov, GE Sadetsky, SM Schapkin, GN Schott, W Semenchuk, GG Smirenin, YV Soroka, MA Vasiliev, AA Vorobyov, AA Voropaev, NI Zmeskal, J AF Maev, EM Balin, DV Case, T Crowe, KM Del Rosso, A Ganzha, VA Hartmann, FJ Kozlov, SM Lauss, B Maev, OE Muhlbauer, M Mulhauser, F Petitjean, C Petrov, GE Sadetsky, SM Schapkin, GN Schott, W Semenchuk, GG Smirenin, YV Soroka, MA Vasiliev, AA Vorobyov, AA Voropaev, NI Zmeskal, J TI Measurement of the muon transfer rate from deuterium to He-3 at low temperature SO HYPERFINE INTERACTIONS LA English DT Article; Proceedings Paper CT International Workshop on Exotic Atoms, Molecules and Muon Catalyzed Fusion (EXAT98) CY JUL 19-24, 1998 CL UNIV FRIBOURG, FRIBOURG, SWITZERLAND SP ETH Zurich, Ctr Stefano Franscini, Paul Scherrer Inst, Univ Fribourg, Swiss Natl Fdn HO UNIV FRIBOURG ID HYDROGEN AB The muon transfer rate (<(lambda)over tilde>(d3He)) from deuterium to He-3 at temperatures of 39.5 K and 50.0 K, respectively, has been determined as a by-product of the experiment aimed to search for muon catalyzed d(3)He-fusion. The measurements were performed in the muon beam at PSI with a multi-anode high pressure ionization chamber as a target and detector of the incoming muons and the charged reaction products. The chamber was filled with the HD+He-3(5.6%) gas mixture of 9.21% LHD density. The analysis of time distributions of dd-fusion events was able to determine the transfer rates: <(lambda)over tilde>(d3He)(50 K)=(2.32 +/- 0.09) x 10(8) s(-1), <(lambda)over tilde>(d3He)(39.5 K)=(2.33 +/- 0.16) . 10(8) s(-1). These values, normalized to liquid hydrogen density (LHD, 4.25 . 10(22) atoms/cm(3)), significantly exceed the transfer rates at room temperature, in agreement with theoretical predictions. C1 Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Univ Calif Berkeley, Berkeley, CA 94720 USA. LBNL, Berkeley, CA 94720 USA. Univ Fribourg, Inst Phys, CH-1700 Fribourg, Switzerland. Tech Univ Munich, D-85747 Garching, Germany. Austrian Acad Sci, A-1090 Vienna, Austria. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. RP Petersburg Nucl Phys Inst, Gatchina 188350, Russia. EM maev@hep486.pnpi.spb.ru; case@sseos.lbl.gov; antonella.delrosso@unifr.ch; hartmann@e18.physik.tu-muenchen.de; lauss@aimep0.imep.UniVie.ac.at; muehlbauer@ubaclu.unibas.ch; mulhauser@ufper6.unifr.ch; petitjean@psi.ch; semench@hep486.pnpi.spb.ru; vorobyov@rec03.pnpi.spb.ru; voropaev@hep486.pnpi.spb.ru NR 5 TC 4 Z9 4 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 119 IS 1-4 BP 121 EP 125 DI 10.1023/A:1012671022090 PG 5 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EL UT WOS:000080977500017 ER PT J AU Kammel, P AF Kammel, P TI High intensity muon pion beam with time structure at PSI SO HYPERFINE INTERACTIONS LA English DT Article; Proceedings Paper CT International Workshop on Exotic Atoms, Molecules and Muon Catalyzed Fusion (EXAT98) CY JUL 19-24, 1998 CL UNIV FRIBOURG, FRIBOURG, SWITZERLAND SP ETH Zurich, Ctr Stefano Franscini, Paul Scherrer Inst, Univ Fribourg, Swiss Natl Fdn HO UNIV FRIBOURG DE muon capture; muon lifetime; Standard Model parameters AB A new initiative is presented to develop a high intensity muon/pion beam with a time structure optimized to the muon lifetime. Such a facility would provide exciting physics opportunities for dramatically improved fundamental experiments, e.g., in the field of muon capture, muon lifetime and muonium spectroscopy. The high primary beam intensity at PSI allows intense chopped muon beams by installing a fast electrostatic kicker in a secondary channel. Two modes of operation are foreseen: a muon-on-request scheme, which uses active feedback from a beam counter in the experimental area and a periodic pulsed mode with about 5-20% duty factor. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Kammel, P (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 8 TC 4 Z9 4 U1 0 U2 0 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 119 IS 1-4 BP 323 EP 328 DI 10.1023/A:1012680618881 PG 6 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EL UT WOS:000080977500046 ER PT J AU Vorobyov, AA Ackerbauer, P Adamczak, A Andreev, VA Balin, DV Beer, GA Breunlich, WH Case, T Crowe, KM Daniel, H Deutsch, J Dick, PU Dijksman, A Egger, J von Egidy, T Faifman, MP Fetisov, AA Ganzha, VA Govaerts, J Gusev, VV Hartmann, FJ Herold, WD Kammel, P Krivshich, AG Lauss, B Maev, EM Markushin, VE Martino, J Marton, J Menshikov, LI Muhlbauer, M Petitjean, C Petitjean, T Petrov, GE Ponomarev, LI Prieels, R Prymas, W Schapkin, GN Schops, W Schott, W Semenchuk, GG Smirenin, YV Voropaev, NI AF Vorobyov, AA Ackerbauer, P Adamczak, A Andreev, VA Balin, DV Beer, GA Breunlich, WH Case, T Crowe, KM Daniel, H Deutsch, J Dick, PU Dijksman, A Egger, J von Egidy, T Faifman, MP Fetisov, AA Ganzha, VA Govaerts, J Gusev, VV Hartmann, FJ Herold, WD Kammel, P Krivshich, AG Lauss, B Maev, EM Markushin, VE Martino, J Marton, J Menshikov, LI Muhlbauer, M Petitjean, C Petitjean, T Petrov, GE Ponomarev, LI Prieels, R Prymas, W Schapkin, GN Schops, W Schott, W Semenchuk, GG Smirenin, YV Voropaev, NI TI Final results on the mu He-3-capture experiment and perspectives for mu p-capture studies SO HYPERFINE INTERACTIONS LA English DT Article ID PSEUDOSCALAR COUPLING-CONSTANT; HE-3 AB Muon capture on hydrogen gives a unique possibility for a measurement of the pseudo-scalar form factor g(p) (q(c)(2) = -0.88 m(mu)(2)) of the nucleonic weak current, thus providing a sensitive test of the QCD chiral symmetry perturbation theory which predicts the value of this form factor with a precision of Delta g(p)/g(p) similar or equal to 2%. For adequate comparison with theory, the muon capture rate Lambda(c) should be measured with a precision of Delta Lambda(c)/Lambda(c) less than or equal to 1%, that is an order of magnitude better than the precision of the present world data. We report on the project of an experiment designed to provide the required precision. Also, we present the final result of our previous experiment on a high precision measurement of the \mu(3)He capture rate and compare this result with the PCAC prediction. C1 Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Austrian Acad Sci, A-1090 Vienna, Austria. Inst Nucl Phys, PL-31342 Krakow, Poland. Univ Victoria, Victoria, BC V8W 2Y2, Canada. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Tech Univ Munich, Dept Phys, D-85720 Garching, Germany. Univ Catholique Louvain, B-1348 Louvain, Belgium. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Russian Res Ctr Kurchatov Inst, Moscow 123182, Russia. CEA Saclay, F-91191 Gif Sur Yvette, France. RP Vorobyov, AA (reprint author), Petersburg Nucl Phys Inst, Gatchina 188350, Russia. RI Marton, Johann/H-2668-2012 OI Marton, Johann/0000-0001-5139-7720 NR 21 TC 4 Z9 4 U1 0 U2 1 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 118 IS 1-4 BP 13 EP 24 DI 10.1023/A:1012616015304 PG 12 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EB UT WOS:000080976300003 ER PT J AU Marshall, GM Porcelli, TA Adamczak, A Bailey, JM Beer, GA Faifman, MP Fujiwara, MC Huber, TM Jacot-Guillarmod, R Kammel, P Kim, SK Knowles, PE Kunselman, AR Maier, M Markushin, VE Mason, GR Mulhauser, F Olin, A Petitjean, C Zmeskal, J AF Marshall, GM Porcelli, TA Adamczak, A Bailey, JM Beer, GA Faifman, MP Fujiwara, MC Huber, TM Jacot-Guillarmod, R Kammel, P Kim, SK Knowles, PE Kunselman, AR Maier, M Markushin, VE Mason, GR Mulhauser, F Olin, A Petitjean, C Zmeskal, J TI Resonant formation measurements of dt mu via time of flight SO HYPERFINE INTERACTIONS LA English DT Article DE muon catalyzed fusion; resonant formation; muonic atoms; muonic hydrogen; exotic atoms ID D-T FUSION; CATALYZED FUSION; HYDROGEN ISOTOPES; DEUTERIUM; TRITIUM; VACUUM AB Solid hydrogen in the form of an inhomogeneous layered target offers several experimental advantages when compared with liquid or gas. Beams of non-thermalized muonic hydrogen atoms allow us to explore resonant molecular ion formation processes near eV kinetic energies. Isotopically specific layers make it possible to separate competing and confusing interactions and to employ the time of flight for comparison with predictions based on theoretical energy dependences. Unambiguous charged fusion product detection simplifies absolute intensity measurements. The systematic uncertainties encountered in resonant molecular ion formation measurements, using solid hydrogen target layers, are being investigated with simulations which use the many calculated energy-dependent rates and cross-sections which are now available. The importance of the rates for processes such as muon transfer and elastic scattering are discussed, and results of some recent analyses are presented. C1 TRIUMF, Vancouver, BC V6T 2A3, Canada. Univ Victoria, Victoria, BC V8W 3P6, Canada. Inst Nucl Phys, PL-31342 Krakow, Poland. Chester Technol, Chester, Cheshire, England. Russian Res Ctr Kurchatov Inst, Moscow 123182, Russia. Univ British Columbia, Vancouver, BC V6T 1Z1, Canada. Gustavus Adolphus Coll, St Peter, MN 56082 USA. Univ Fribourg, Inst Phys, CH-1700 Fribourg, Switzerland. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Jeonbuk Natl Univ, Jeonju 560756, South Korea. Univ Wyoming, Laramie, WY 82071 USA. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Austrian Acad Sci, A-1090 Vienna, Austria. RP TRIUMF, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3, Canada. EM mrshl@triumf.ca NR 30 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 118 IS 1-4 BP 89 EP 101 DI 10.1023/A:1012636619847 PG 13 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EB UT WOS:000080976300013 ER PT J AU Bom, VR Bradbury, JN Davies, JD Demin, AM Demin, DL Drebushko, AE Dzhelepov, VP van Eijk, CWE Filchenkov, VV Golubkov, AN Grafov, NN Grebinnik, VG Grishechkin, SK Klevtsov, VG Konin, AD Kukolkin, AA Medved', SV Nazarov, VA Perevozchikov, VV Pryanichnikov, VI Rozhkov, VY Rudenko, AI Sadetsky, SM Semenchuk, GG Sidorov, VT Smirenin, YV Sukhoi, II Voropaev, NI Yukhimchuk, AA Zinov, VG Zlatoustovskii, SV AF Bom, VR Bradbury, JN Davies, JD Demin, AM Demin, DL Drebushko, AE Dzhelepov, VP van Eijk, CWE Filchenkov, VV Golubkov, AN Grafov, NN Grebinnik, VG Grishechkin, SK Klevtsov, VG Konin, AD Kukolkin, AA Medved', SV Nazarov, VA Perevozchikov, VV Pryanichnikov, VI Rozhkov, VY Rudenko, AI Sadetsky, SM Semenchuk, GG Sidorov, VT Smirenin, YV Sukhoi, II Voropaev, NI Yukhimchuk, AA Zinov, VG Zlatoustovskii, SV TI Temperature and density dependence of mu-catalysis cycling rate in dense D T and H/D/T gas mixtures SO HYPERFINE INTERACTIONS LA English DT Article ID FUSION; DEUTERIUM; TRITIUM AB Muon catalyzed dt fusion in dense D/T and H/D/T gas mixtures of hydrogen isotopes is studied by the MCF collaboration at JINR. The measurements were carried out with a high pressure target at the JINR phasotron in the temperature range 300-800 K at mixture densities similar or equal to 0.4 and similar or equal to 0.8 LHD. Tentative experimental results obtained by several analysis methods are presented. C1 Delft Univ Technol, NL-2629 JB Delft, Netherlands. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Russian Fed Nucl Ctr, All Russian Res Inst Expt Phys, Sarov 607200, Nizhniy Novgoro, Russia. Joint Inst Nucl Res, Lab Nucl Problems, Dubna 141980, Russia. St Petersburg Nucl Phys Inst, Gatchina 188350, Russia. RP Bom, VR (reprint author), Delft Univ Technol, NL-2629 JB Delft, Netherlands. RI Bom, Victor/C-5691-2008 NR 15 TC 14 Z9 14 U1 1 U2 1 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 118 IS 1-4 BP 103 EP 109 DI 10.1023/A:1012688603918 PG 7 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EB UT WOS:000080976300014 ER PT J AU Averin, YP Balin, DV Bom, VR Bradbury, JN Davies, JD Demin, AM Demin, DL Drebushko, AE Dzhelepov, VP van Eijk, CWE Filchenkov, VV Golubkov, AN Grafov, NN Grebinnik, VG Grishechkin, SK Klevtsov, VG Konin, AD Kukolkin, AA Medved', SV Modenov, AB Nazarov, VA Perevozchikov, VV Pryanichnikov, VI Rozhkov, VY Rudenko, AI Sadetsky, SM Semenchuk, GG Sidorov, VT Smirenin, YV Sukhoi, II Travkin, VV Voropaev, NI Yukhimchuk, AA Zinov, VG Zlatoustovskii, SV AF Averin, YP Balin, DV Bom, VR Bradbury, JN Davies, JD Demin, AM Demin, DL Drebushko, AE Dzhelepov, VP van Eijk, CWE Filchenkov, VV Golubkov, AN Grafov, NN Grebinnik, VG Grishechkin, SK Klevtsov, VG Konin, AD Kukolkin, AA Medved', SV Modenov, AB Nazarov, VA Perevozchikov, VV Pryanichnikov, VI Rozhkov, VY Rudenko, AI Sadetsky, SM Semenchuk, GG Sidorov, VT Smirenin, YV Sukhoi, II Travkin, VV Voropaev, NI Yukhimchuk, AA Zinov, VG Zlatoustovskii, SV TI Novel method for MCF study in a dense D T mixture, first experimental results SO HYPERFINE INTERACTIONS LA English DT Article DE muon; fusion; cycling rate ID MUON-CATALYZED FUSION; STICKING; TRITIUM AB Preliminary data are first presented for the measurements of effective parameters of MCF processes in dense D/T mixtures obtained by a novel method. Results are compared with the ones obtained by the "standard" method. C1 Russian Fed Nucl Ctr, All Russian Res Inst Expt Phys, Sarov 607200, Nizhniy Novgoro, Russia. St Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Delft Univ Technol, NL-2629 JB Delft, Netherlands. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Joint Inst Nucl Res, Lab Nucl Problems, Dubna 141980, Russia. RP Averin, YP (reprint author), Russian Fed Nucl Ctr, All Russian Res Inst Expt Phys, Sarov 607200, Nizhniy Novgoro, Russia. RI Bom, Victor/C-5691-2008 NR 15 TC 16 Z9 16 U1 0 U2 0 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 118 IS 1-4 BP 111 EP 119 DI 10.1023/A:1012640720756 PG 9 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EB UT WOS:000080976300015 ER PT J AU Petitjean, C Balin, DV Breunlich, WH Case, T Crowe, KM Daniel, H Faifman, MP Ganzha, VA Gartner, B Hartmann, FJ Kammel, P Kozlov, S Lauss, B Maev, EM Markushin, VE Misko, YA Muhlbauer, M Petrov, GE Prymas, W Schapkin, GN Schott, W Semenchuk, GG Smirenin, YV Trofimov, VA Vasiliev, AA Vorobyov, AA Voropaev, NI Zmeskal, J AF Petitjean, C Balin, DV Breunlich, WH Case, T Crowe, KM Daniel, H Faifman, MP Ganzha, VA Gartner, B Hartmann, FJ Kammel, P Kozlov, S Lauss, B Maev, EM Markushin, VE Misko, YA Muhlbauer, M Petrov, GE Prymas, W Schapkin, GN Schott, W Semenchuk, GG Smirenin, YV Trofimov, VA Vasiliev, AA Vorobyov, AA Voropaev, NI Zmeskal, J TI Muon catalyzed fusion in deuterium gas SO HYPERFINE INTERACTIONS LA English DT Article DE exotic atom; muonic molecule ID DD-FUSION; HYDROGEN AB We present the results of an experiment performed at PSI to investigate muon catalyzed fusion in pure deuterium gas of 5% density (LHD) at temperatures ranging from 28 K to 350 K. Using a new high pressure ionization chamber the reactions dd --> n + He-3 and dd --> p + t were observed with 100% detection efficiency. The rates of d mu d formation were measured with the absolute precision of 1% and the mu d spin-flip rates with 0.5%. The temperature dependence of molecular formation and spin-flip rates display pronounced resonance structures. A preliminary fit based on the Vesman mechanism of resonant muonic molecule formation was carried out yielding a dd fusion rate of 3.5 . 10(8) s(-1) and a hfs splitting energy delta epsilon(d mu d) of 24.3 meV, both in good agreement with the theory. C1 Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Austrian Acad Sci, A-1090 Vienna, Austria. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Tech Univ Munich, D-85747 Garching, Germany. Russian Res Ctr Kurchatov Inst, Moscow 123182, Russia. RP Paul Scherrer Inst, CH-5232 Villigen, Switzerland. NR 32 TC 20 Z9 20 U1 0 U2 7 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 118 IS 1-4 BP 127 EP 133 DI 10.1023/A:1012644821665 PG 7 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EB UT WOS:000080976300017 ER PT J AU Voropaev, NI Balin, DV Breunlich, WN Case, T Crowe, KM Daniel, H Ganzha, VA Gartner, B Hartmann, FJ Kammel, P Kozlov, SM Lauss, B Maev, EM Markushin, VE Misko, YA Muhlbauer, M Petitjean, C Petrov, GE Prymas, W Schapkin, GN Schott, W Semenchuk, GG Smirenin, YV Trofimov, VA Vasiliev, AA Vorobyov, AA Zmeskal, J AF Voropaev, NI Balin, DV Breunlich, WN Case, T Crowe, KM Daniel, H Ganzha, VA Gartner, B Hartmann, FJ Kammel, P Kozlov, SM Lauss, B Maev, EM Markushin, VE Misko, YA Muhlbauer, M Petitjean, C Petrov, GE Prymas, W Schapkin, GN Schott, W Semenchuk, GG Smirenin, YV Trofimov, VA Vasiliev, AA Vorobyov, AA Zmeskal, J TI First observation of spin flip in d mu-atoms via formation and back decay of dd mu molecules SO HYPERFINE INTERACTIONS LA English DT Article ID FUSION AB We present the results of precision measurements of d mu spin-flip rates in pure D(2), in pure HD gas, and in the non-equilibrium and equilibrium H(2) + D(2) gas mixtures. The experiments were performed at PSI in 1994-1996 using the high pressure ionization chamber from Gatchina as a 100\% efficient detector of the charged fusion products. The measurements have been carried out in the temperature range 28-300 K, at gas density of 5% of LHD. In pure deuterium, the measured temperature dependence of the spin-flip rate allowed us to separate the two components (resonant and non-resonant) of the spin-flip processes. From the experiments in H/D mixtures we have measured the non-resonant spin-flip rate in collisions of d mu-atoms with HD molecules. Comparison with the theory revealed considerable disagreement in the case of non-resonant spin-flip in collisions of the d mu-atoms with D(2) molecules. C1 Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Austrian Acad Sci, A-1090 Vienna, Austria. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Tech Univ Munich, D-85747 Garching, Germany. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. RP Voropaev, NI (reprint author), Petersburg Nucl Phys Inst, Gatchina 188350, Russia. NR 6 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 118 IS 1-4 BP 135 EP 140 DI 10.1023/A:1012696805735 PG 6 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EB UT WOS:000080976300018 ER PT J AU Semenchuk, GG Balin, DV Case, T Crowe, KM Ganzha, VA Hartmann, FJ Kozlov, SM Lauss, B Maev, EM Muhlbauer, M Petitjean, C Petrov, GE Sadetsky, SM Schapkin, GN Schott, W Smirenin, YV Soroka, MA Vasiliev, AA Vorobyov, AA Voropaev, NI Zmeskal, J AF Semenchuk, GG Balin, DV Case, T Crowe, KM Ganzha, VA Hartmann, FJ Kozlov, SM Lauss, B Maev, EM Muhlbauer, M Petitjean, C Petrov, GE Sadetsky, SM Schapkin, GN Schott, W Smirenin, YV Soroka, MA Vasiliev, AA Vorobyov, AA Voropaev, NI Zmeskal, J TI Study of muon catalyzed dd-fusion in HD gas SO HYPERFINE INTERACTIONS LA English DT Article AB The results of an experiment on muon catalyzed dd-fussion in HD gas are presented. The experiment was performed at the muon beam of PSI using a high-pressure ionization chamber filled with pure HD-gas of low D-2 concentration on the level 1%, at temperatures 50, 150 and 300 K. The non-resonant character of dd mu-molecule formation on HD molecules was confirmed by measuring the ratio of yields of the two dd mu-fusion channels, R = Y(He-3,n)/Y(H-3,p), which proved to be close to unity. The dd mu formation rate was found to vary from lambda(dd mu-HD) = 0.05.10(6) s(-1) at T = 50 K to lambda(dd mu-HD) = 0.12.10(6) s(-1) at T = 300 K, in agreement with the theoretical prediction. A prominent peak at t < 60 ns was observed in the time spectrum of fusion neutrons indicating a resonant contribution of dd\mu formation from epithermal d\mu atoms. C1 Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Tech Univ Munich, D-85747 Garching, Germany. Austrian Acad Sci, A-1090 Vienna, Austria. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. RP Petersburg Nucl Phys Inst, Gatchina 188350, Russia. NR 14 TC 4 Z9 4 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 118 IS 1-4 BP 141 EP 146 DI 10.1023/A:1012648922573 PG 6 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EB UT WOS:000080976300019 ER PT J AU Fujiwara, MC Adamczak, A Bailey, JM Beer, GA Beveridge, JL Faifman, MP Huber, TM Jacot-Guillarmod, R Kammel, P Kim, SK Knowles, PE Kunselman, AR Maier, M Markushin, VE Marshall, GM Martoff, CJ Mason, GR Mulhauser, F Olin, A Petitjean, C Porcelli, TA Wozniak, J Zmeskal, J AF Fujiwara, MC Adamczak, A Bailey, JM Beer, GA Beveridge, JL Faifman, MP Huber, TM Jacot-Guillarmod, R Kammel, P Kim, SK Knowles, PE Kunselman, AR Maier, M Markushin, VE Marshall, GM Martoff, CJ Mason, GR Mulhauser, F Olin, A Petitjean, C Porcelli, TA Wozniak, J Zmeskal, J TI Time-of-flight spectroscopy of muonic tritium SO HYPERFINE INTERACTIONS LA English DT Article DE muonic hydrogen; muon catalyzed fusion; Ramsauer-Townsend effect ID HYDROGEN; VACUUM AB Emission of muonic tritium from a solid hydrogen layer has been studied via imaging of the muon-decay electrons and the time-of-flight distributions have been compared with detailed Monte Carlo calculations. Results are consistent at the 10% level with the theoretical prediction of a Ramsauer-Townsend minimum cross-section energy. C1 Univ British Columbia, Vancouver, BC V5Z 1M9, Canada. Inst Nucl Phys, Krakow, Poland. Chester Technol, Chester, Cheshire, England. Univ Victoria, Victoria, BC, Canada. TRIUMF, Vancouver, BC V6T 2A3, Canada. IV Kurchatov Atom Energy Inst, Moscow 123182, Russia. Gustavus Adolphus Coll, St Peter, MN 56082 USA. Univ Fribourg, Inst Phys, CH-1700 Fribourg, Switzerland. Univ Calif Berkeley, LBNL, Berkeley, CA 94720 USA. Jeonbuk Natl Univ, Jeonju, South Korea. Univ Wyoming, Laramie, WY 82071 USA. PSI, Villigen, Switzerland. Temple Univ, Philadelphia, PA 19122 USA. Inst Phys & Nucl Tech, Krakow, Poland. Austrian Acad Sci, A-1010 Vienna, Austria. RP Univ British Columbia, Vancouver, BC V5Z 1M9, Canada. EM fujiwara@triumf.ca NR 11 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 118 IS 1-4 BP 151 EP 157 DI 10.1023/A:1012653023482 PG 7 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EB UT WOS:000080976300021 ER PT J AU Maev, EM Balin, DV Case, T Crowe, KM Del Rosso, A Ganzha, VA Hartmann, FJ Kozlov, SM Lauss, B Maev, OE Muhlbauer, M Mulhauser, F Petitjean, C Petrov, GE Sadetsky, SM Schapkin, GN Schott, W Semenchuk, GG Smirenin, YV Soroka, MA Vasiliev, AA Vorobyov, AA Voropaev, NI Zmeskal, J AF Maev, EM Balin, DV Case, T Crowe, KM Del Rosso, A Ganzha, VA Hartmann, FJ Kozlov, SM Lauss, B Maev, OE Muhlbauer, M Mulhauser, F Petitjean, C Petrov, GE Sadetsky, SM Schapkin, GN Schott, W Semenchuk, GG Smirenin, YV Soroka, MA Vasiliev, AA Vorobyov, AA Voropaev, NI Zmeskal, J TI Search for muon catalyzed d(3)He-fusion SO HYPERFINE INTERACTIONS LA English DT Article ID DECAY AB We report on the results of an experiment aimed at observing muon-catalyzed d(3)He-fusion with a setup previously used for studies of the muon-catalyzed dd-fusion. The basic element of the setup is a high pressure ionization chamber operating as an active target. In this experiment the chamber was filled with an HD + He-3 (5.6%) gas mixture at 13.2 bar pressure and 50 K temperature. These conditions were chosen as optimal for formation of the He-3 mu d-molecules with a low level of background from the d-mu-d fusion. The chamber was exposed to the negative muon beam at PSI. During a 3-week data-taking period, 9.7 x 10(8) muon stops have been selected. The analysis of the data was able to determine a new upper limit for the d(3)He-fusion rate in the He-3 mu d-molecule (lambda(f) less than or equal to 6 x 10(4) s(-1)), which is more than three orders of magnitude lower than the previously existed limit. C1 Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Univ Calif Berkeley, Berkeley, CA 94720 USA. LBNL, Berkeley, CA 94720 USA. Univ Fribourg, Inst Phys, Perolles, CH-1700 Fribourg, Switzerland. Tech Univ Munich, D-85747 Garching, Germany. Austrian Acad Sci, A-1090 Vienna, Austria. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. RP Maev, EM (reprint author), Petersburg Nucl Phys Inst, Gatchina 188350, Russia. NR 12 TC 10 Z9 10 U1 0 U2 0 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 118 IS 1-4 BP 171 EP 176 DI 10.1023/A:1012609308461 PG 6 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EB UT WOS:000080976300024 ER PT J AU Case, T Balin, DV Breunlich, WH Crowe, KM Daniel, H Gartner, B Hartmann, FJ Kammel, P Lauss, B Maev, EM Markushin, VE Muhlbauer, M Petitjean, C Petrov, GE Prymas, W Schapkin, GN Schott, W Semenchuk, GG Smirenin, YV Vasiliev, AA Vorobyov, AA Voropaev, NI Zmeskal, J AF Case, T Balin, DV Breunlich, WH Crowe, KM Daniel, H Gartner, B Hartmann, FJ Kammel, P Lauss, B Maev, EM Markushin, VE Muhlbauer, M Petitjean, C Petrov, GE Prymas, W Schapkin, GN Schott, W Semenchuk, GG Smirenin, YV Vasiliev, AA Vorobyov, AA Voropaev, NI Zmeskal, J TI Insights on d mu t sticking from d mu d stripping and mu He-3 capture SO HYPERFINE INTERACTIONS LA English DT Article DE muon catalyzed fusion; sticking; stripping ID OMEGA-S; FUSION AB Data from the recent PSI high statistics experiment on d mu d fusion are used to measure the stripping process in d mu d --> n + mu He-3 and test current calculations of the stripping process. The PSI results in mu He-3 capture are also used to remove a troubling background from this measurement. Combination of these results with the old d mu t sticking analysis slightly raise and improve that result to omega(s) = (0.58 +/- 0.04)% and indicate that theory and experiment can meet if theoretical stripping is increased only at the beginning of the track. This conclusion is in accord with the new stripping calculations where excited state stripping is increased significantly. C1 Univ Calif Berkeley, Berkeley, CA 94720 USA. LBNL, Berkeley, CA 94720 USA. Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Austrian Acad Sci, A-1090 Vienna, Austria. Tech Univ Munich, D-85747 Garching, Germany. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. RP Case, T (reprint author), Univ Calif Berkeley, Berkeley, CA 94720 USA. NR 8 TC 3 Z9 3 U1 0 U2 0 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PY 1999 VL 118 IS 1-4 BP 197 EP 202 DI 10.1023/A:1012617510278 PG 6 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 208EB UT WOS:000080976300028 ER PT S AU He, C Zweig, G AF He, C Zweig, G GP IEEE IEEE TI Adaptive two-band spectral subtraction with multi-window spectral estimation SO ICASSP '99: 1999 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH, AND SIGNAL PROCESSING, PROCEEDINGS VOLS I-VI SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP 99) CY MAR 15-19, 1999 CL PHOENIX, AZ SP IEEE, IEEE Signal Proc Soc AB An improved spectral subtraction algorithm for enhancing speech corrupted by additive wideband noise is described. The artifactual noise introduced by spectral subtraction that is perceived as musical noise is 7 dB less than that introduced by the classical spectral subtraction algorithm of Berouti et al. Speech is decomposed into voiced and unvoiced sections. Since voiced speech is primarily stochastic at high frequencies, the voiced speech is high-pass filtered to extract its stochastic component. The cut-off frequency is estimated adaptively. Multi-window spectral estimation is used to estimate the spectrum of stochastically voiced and unvoiced speech, thereby reducing the spectral variance. A low-pass filter is used to extract the deterministic component of voiced speech. Its spectrum is estimated with a single window. Spectral subtraction is performed with the classical algorithm using the estimated spectra. Informal listening tests confirm that the new algorithm creates significantly less musical noise than the classical algorithm. C1 Univ Calif Los Alamos Natl Lab, T Div, Los Alamos, NM 87545 USA. RP He, C (reprint author), Univ Calif Los Alamos Natl Lab, T Div, MS B276, Los Alamos, NM 87545 USA. NR 9 TC 0 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-5041-3 J9 INT CONF ACOUST SPEE PY 1999 BP 793 EP 796 DI 10.1109/ICASSP.1999.759790 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Acoustics; Computer Science; Engineering GA BM75N UT WOS:000079690700199 ER PT B AU McBride, DD Henfling, JF Clark, EL AF McBride, DD Henfling, JF Clark, EL GP IEEE IEEE IEEE TI Determining the transfer function for unsteady pressure measurements using a method of characteristics solution SO ICIASF'99: INTERNATIONAL CONGRESS ON INSTRUMENTATION IN AEROSPACE SIMULATION FACILITIES, RECORD LA English DT Proceedings Paper CT 18th International Congress on Instrumentation in Aerospace Simulation Facilities (ICIASF'99) CY JUN 14-17, 1999 CL TOULOUSE, FRANCE SP Onera-Ctr, Inst Elect & Electr Engineers, European Off Aerosp Res & Dev, Delegat Gen Armement, Conseil Reg Midi-Pyrenees, Mairie Toulouse, Co Presenting Instrument Syst AB An inverse Fourier transform method for removing lag from pressure measurements has been used by various researchers, given an experimentally derived transfer function to characterize the pressure plumbing. This paper presents a Method of Characteristics (MOC) solution technique for predicting the transfer function and thus easily determining its sensitivity to various plumbing parameters. The MOC solution has been used in the pipeline industry for some time for application to transient flow in pipelines, but it also lends itself well to this application. For highly nonsteady pressures frequency-dependent friction can cause significant distortion of the traveling waves. This is accounted for in the formulation. A simple bench experiment and proof-of-principle test provide evidence to establish the range of validity of the method. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP McBride, DD (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5716-7 PY 1999 BP 381 EP 389 DI 10.1109/ICIASF.1999.827178 PG 9 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ47C UT WOS:000088436500038 ER PT S AU Pogorelsky, IV Kimura, WD Quimby, DC Andreev, NE Kuznetsov, SV AF Pogorelsky, IV Kimura, WD Quimby, DC Andreev, NE Kuznetsov, SV BE Fedorov, MV Gordienkov, VM Shuvalov, VV Taranukhin, VD TI Experimental approach to laser-driven monochromatic electron accelerators SO ICONO '98: ULTRAFAST PHENOMENA AND INTERACTION OF SUPERSTRONG LASER FIELDS WITH MATTER: NONLINEAR OPTICS AND HIGH-FIELD PHYSICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 16th International Conference on Coherent and Nonlinear Optics (ICONO 98) CY JUN 29-JUL 03, 1998 CL MOSCOW, RUSSIA SP Minist Sci & Technol Russian Federat, Russian Fdn Basic Res, Minist Educ Russian Federat, Basic Opt & Spect Educ & Res Ctr, Opt Soc Amer, SPIE-Int Soc Opt Engn, Int Union Pure & Appl Phys, EPS-European Phys Soc, Lawrence Livermore Natl Lab, European Off Aerosp Res & Dev, SPIE Russia Chapter, US Army European Res Off DE electron beams; CO2 lasers; picosecond pulses; particle acceleration ID PLASMA; PULSES; INJECTION; WAVES AB Practical meaningful mono-energetic laser accelerator requires the electron bunch to be within a small proportion of the period of the accelerating field. By two laser accelerator schemes, we exemplify how the emerging picosecond terawatt (ps-TW) CO2 laser technology helps to satisfy this requirement. These include: a staged electron laser accelerator (STELLA) experiment, which is being conducted at the Brookhaven Accelerator Test Facility (ATF), and a prospective laser wakefield accelerator (LWFA), where ps-TW CO2 lasers may offer noticeable advantages over more conventional T-3 solid-state lasers. C1 Brookhaven Natl Lab, Accelerator Test Facil, Upton, NY 11973 USA. RP Pogorelsky, IV (reprint author), Brookhaven Natl Lab, Accelerator Test Facil, 725C, Upton, NY 11973 USA. NR 18 TC 4 Z9 4 U1 2 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3209-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3735 BP 175 EP 186 DI 10.1117/12.341463 PG 12 WC Optics; Physics, Applied; Physics, Fluids & Plasmas; Physics, Multidisciplinary SC Optics; Physics GA BM94X UT WOS:000080216600021 ER PT B AU Xavier, PG AF Xavier, PG GP IEEE IEEE TI Shortest path planning for a tethered robot or an anchored cable SO ICRA '99: IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS 1-4, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Robotics and Automation (ICRA '99) CY MAY 10-15, 1999 CL DETROIT, MI SP IEEE, Robot & Automat Soc AB We consider the problem of planning shortest paths for a tethered robot with a finite length tether in a 2D environment with polygonal obstacles. We present an algorithm that runs in time O((k(l) + 1)(2)n(4)) and finds the shortest path or correctly determines that none exists that obeys the constraints; here n is the number obstacle vertices, and k(l) is the number loops in the initial configuration of the tether. The robot may cross its tether but nothing can cross obstacles, which cause the tether to bend. The algorithm applies as well for planning a shortest path for the free end of an anchored cable. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 17 TC 11 Z9 13 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5180-0; 0-7803-5181-9 PY 1999 BP 1011 EP 1017 PG 7 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA BN32H UT WOS:000081625700160 ER PT J AU Schwander, P Rau, WD Kisielowski, C Gribelyuk, M Ourmazd, A AF Schwander, P Rau, WD Kisielowski, C Gribelyuk, M Ourmazd, A TI Defect processes in semiconductors studied at the atomic level by transmission electron microscopy SO IDENTIFICATION OF DEFECTS IN SEMICONDUCTORS SE SEMICONDUCTORS AND SEMIMETALS LA English DT Article ID LATTICE IMAGES; POINT-DEFECTS; FOCUS-VARIATION; WAVE-FUNCTION; RESOLUTION; INTERFACES; RECONSTRUCTION; MICROGRAPHS; RETRIEVAL; HREM C1 Inst Semicond Phys, D-15230 Frankfurt, Oder, Germany. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Texas Instruments Inc, Corp Res Labs, Dallas, TX 75243 USA. Tech Univ Brandenburg Cottbus, D-03013 Cottbus, Germany. RP Schwander, P (reprint author), Inst Semicond Phys, Walter Korsing Str 2, D-15230 Frankfurt, Oder, Germany. NR 54 TC 0 Z9 0 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 0080-8784 J9 SEMICONDUCT SEMIMET PY 1999 VL 51 BP 225 EP 259 PN B PG 35 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BM64B UT WOS:000079322800004 ER PT J AU Jager, ND Weber, ER AF Jager, ND Weber, ER TI Scanning tunneling microscopy of defects in semiconductors SO IDENTIFICATION OF DEFECTS IN SEMICONDUCTORS SE SEMICONDUCTORS AND SEMIMETALS LA English DT Article ID SI-DOPED GAAS; ARSENIC ANTISITE DEFECTS; MOLECULAR-BEAM EPITAXY; GAAS(110) SURFACES; POINT-DEFECTS; ELECTRONIC-STRUCTURE; SI(111)2X1 SURFACE; GAP(110) SURFACES; INP(110) SURFACES; VACANCY MIGRATION C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci, Berkeley, CA 94720 USA. RP Jager, ND (reprint author), Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 64 TC 0 Z9 0 U1 1 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 0080-8784 J9 SEMICONDUCT SEMIMET PY 1999 VL 51 BP 261 EP 296 PN B PG 36 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BM64B UT WOS:000079322800005 ER PT J AU Kaarsberg, TM Roop, JM AF Kaarsberg, TM Roop, JM TI Combined heat and power: How much carbon and energy can manufacturers save? SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB In this paper we analyze the potential for CHP in US manufacturing. We use typical efficiencies of today's available CHP technologies to estimate the technical potential for the frozen technology case. We find that if manufacturers in 1994 had self-generated all their steam and electric needs with existing cost-effective CHP technologies, they could have reduced carbon equivalent (=12/44 carbon dioxide) emissions by up to 30 million metric tons of carbon (MtC) or nearly 20 percent, and energy use by nearly an Exajoule (EJ). With growth in manufacturing and expected improvements in CHP technologies, this technical potential could be much larger. However, without environmental regulatory reform and innovation-oriented utility restructuring policies, actual CHP installed by US manufacturers could fall far short. C1 NE Midwest Inst, Washington, DC 20003 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Kaarsberg, TM (reprint author), NE Midwest Inst, 218 D St SE, Washington, DC 20003 USA. NR 13 TC 0 Z9 1 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 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD JAN PY 1999 VL 14 IS 1 BP 7 EP 11 DI 10.1109/62.738348 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 155PL UT WOS:000077955500001 ER PT J AU Bollinger, T Beckman, P AF Bollinger, T Beckman, P TI Linux on the move SO IEEE SOFTWARE LA English DT Editorial Material C1 Mitre Corp, Bedford, MA 01730 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Bollinger, T (reprint author), Mitre Corp, Bedford, MA 01730 USA. NR 0 TC 1 Z9 1 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 0740-7459 J9 IEEE SOFTWARE JI IEEE Softw. PD JAN-FEB PY 1999 VL 16 IS 1 BP 30 EP + DI 10.1109/MS.1999.744564 PG 4 WC Computer Science, Software Engineering SC Computer Science GA 160BY UT WOS:000078211500018 ER PT J AU Benner, JP AF Benner, JP TI Viewpoint: Photovoltaics in transit to significant role SO IEEE SPECTRUM LA English DT Editorial Material C1 Natl Ctr Photovolta, Natl Renewable Energy Lab, Elect Mat & Devices Div, Golden, CO USA. RP Benner, JP (reprint author), Natl Ctr Photovolta, Natl Renewable Energy Lab, Elect Mat & Devices Div, Golden, CO USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9235 J9 IEEE SPECTRUM JI IEEE Spectr. PD JAN PY 1999 VL 36 IS 1 BP 66 EP 67 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 155AJ UT WOS:000077923100026 ER PT J AU Kolev, PV Deen, MJ Kierstead, J Citterio, M AF Kolev, PV Deen, MJ Kierstead, J Citterio, M TI Constant-resistance deep-level transient spectroscopy in Si and Ge JFET's SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article ID SILICON DETECTORS; CONDUCTANCE DLTS; BULK TRAPS; CAPACITANCE; DEFECT; SEMICONDUCTORS; INTERFACE; DEVICES; CENTERS; STATES AB The recently introduced constant-resistance deep-level transient spectroscopy (CR-DLTS) was successfully applied to study virgin and radiation-damaged junction field-effect transistors (JFET's). We have studied three groups of devices: commercially available discrete silicon JFET's; virgin and exposed to high-level neutron radiation silicon JFET's, custom-made by using a monolithic technology; and commercially available discrete germanium p-channel JPET's. CR-DLTS is similar to both the conductance DLTS and to the constant-capacitance variation (CC-DLTS). Unlike the conductance and current DLTS, it is independent of the transistor size and does not require simultaneous measurement of the transconductance or the free-carrier mobility for calculation of the trap concentration. Compared to the CC-DLTS, it measures only the traps inside the gate-controlled part of the space charge region. Comparisons have also been made with the CC-DLTS and standard capacitance DLTS. In addition, possibilities for defect profiling in the channel have been demonstrated. CR-DLTS was found to be a simple, very sensitive, and device area-independent technique which is well suited for measurement of a wide range of deep level concentrations in transistors. C1 Simon Fraser Univ, Sch Engn Sci, Burnaby, BC V5A 1S6, Canada. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Kolev, PV (reprint author), Simon Fraser Univ, Sch Engn Sci, Burnaby, BC V5A 1S6, Canada. RI Deen, M./A-7567-2008 OI Deen, M./0000-0002-6390-0933 NR 54 TC 6 Z9 6 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD JAN PY 1999 VL 46 IS 1 BP 204 EP 213 DI 10.1109/16.737460 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 152GU UT WOS:000077769000027 ER PT J AU Tolbert, LM Peng, FZ Habetler, TG AF Tolbert, LM Peng, FZ Habetler, TG TI Multilevel converters for large electric drives SO IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS LA English DT Article; Proceedings Paper CT IEEE Applied Power Electronics Conference and Exposition CY FEB 15-19, 1998 CL ANAHEIM, CA SP IEEE DE cascade inverter; common-mode voltage; diode-clamped inverter; electric vehicle; motor drive; multilevel converter; multilevel inverter ID INVERTERS; COMPENSATION; PERFORMANCE; SYSTEMS AB This paper presents transformerless multilevel converters as an application for high-power and/or high-voltage electric motor drives. Multilevel converters: 1) can generate near-sinusoidal voltages with only fundamental frequency switching; 2) have almost no electromagnetic interference or common-mode voltage; and 3) are suitable for large voltampere-rated motor drives and high voltages, The cascade inverter is a natural fit for large automotive ail-electric drives because it uses several levels of de voltage sources, which would be available from batteries or fuel cells. The back-to-back diode-clamped converter is ideal where a source of ac voltage is available, such as in a hybrid electric vehicle. Simulation and experimental results show the superiority of these two converters over two-level pulsewidth-modulation-based drives. C1 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), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. OI Tolbert, Leon/0000-0002-7285-609X NR 22 TC 562 Z9 599 U1 2 U2 30 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0093-9994 J9 IEEE T IND APPL JI IEEE Trans. Ind. Appl. PD JAN-FEB PY 1999 VL 35 IS 1 BP 36 EP 44 DI 10.1109/28.740843 PG 9 WC Engineering, Multidisciplinary; Engineering, Electrical & Electronic SC Engineering GA 161LU UT WOS:000078291100005 ER PT J AU Sablik, MJ Jiles, DC AF Sablik, MJ Jiles, DC TI Modeling the effects of torsional stress on hysteretic magnetization SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 9th Symposium on Electromagnetic Launch Technology CY MAY 13-15, 1998 CL EDINBURGH, SCOTLAND SP Univ Texas Inst Adv Technol DE magnetic hysteresis; magnetomechanical modeling; torque sensor; torsional stress ID POLARIZED RING; TORQUE; PERFORMANCE AB Opposite torques applied axially to a polycrystalline ferromagnetic rod result in tensile and compressive stresses acting perpendicularly at the rod surface at 45 degrees to the rod asis, These stresses affect the magnetization of the rod when a magnetic field is applied parallel to the rod asis. it is shown hom one can formulate the magnetomechanical hysteresis model so as to treat this special case of biaxial stress and take into account the effect of opposite torques on the magnetic properties of the rod. Variation of hysteresis parameters such as coercive field, remanent Bus density, differential permeability at the coercive held, and hysteresis loss as a function of applied torque are determined from the model. In the model, the torque is applied first and then the field is cycled to give hysteresis loops. It is found that the torque dependence of the magnetic properties is different, depending on what is chosen for H-max, the maximum value of the applied magnetic field H. The best parameter to use for tracking the torque is found to be H-c at saturation or near saturation, since that parameter shows an almost linear decrease with the applied torque. C1 SW Res Inst, San Antonio, TX 78228 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Sablik, MJ (reprint author), SW Res Inst, 6220 Culebra Rd, San Antonio, TX 78228 USA. RI Jiles, David/H-9548-2012 NR 25 TC 30 Z9 32 U1 3 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JAN PY 1999 VL 35 IS 1 BP 498 EP 504 DI 10.1109/20.737472 PN 2 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 156PC UT WOS:000078009100004 ER PT J AU Ghafurian, R Dietz, RN Rodenbaugh, T Dominguez, J Tai, N AF Ghafurian, R Dietz, RN Rodenbaugh, T Dominguez, J Tai, N TI Leak location in fluid filled cables using the PFT method SO IEEE TRANSACTIONS ON POWER DELIVERY LA English DT Article DE pipe-type; self-contained; leak location; dielectric fluid leaks; fluid-filled cable AB A new method of pinpointing dielectric fluid leaks on pipe-type and self-contained cables using perfluorocarbon tracer (PFT) is presented. The method has successfully been used on the Con Edison transmission system to locate leaks of dielectric fluid on both types of cables. Application of the PFT technique does not require feeder deenergization and provides major advantages over the conventional method of freeze and pressure testing. Description of the method and results of field application are presented in the paper. C1 Consolidated Edison Co New York Inc, New York, NY 10003 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ghafurian, R (reprint author), Consolidated Edison Co New York Inc, New York, NY 10003 USA. NR 9 TC 5 Z9 5 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-8977 J9 IEEE T POWER DELIVER JI IEEE Trans. Power Deliv. PD JAN PY 1999 VL 14 IS 1 BP 18 EP 22 DI 10.1109/61.736673 PG 5 WC Engineering, Electrical & Electronic SC Engineering GA 151BJ UT WOS:000077700800003 ER PT J AU Bartkowiak, M Comber, MG Mahan, GD AF Bartkowiak, M Comber, MG Mahan, GD TI Failure modes and energy absorption capability of ZnO varistors SO IEEE TRANSACTIONS ON POWER DELIVERY LA English DT Article DE metal-oxide surge arresters; varistors; energy absorption capability; failure modes; time to failure; electrical nonuniformity; thermal stability; current pulses ID OXIDE SURGE ARRESTERS; CURRENTS AB Thermal and mechanical behavior of ZnO varistors used in surge arresters is simulated for current pulses of various magnitude and duration. Time dependence of the temperature profile and of the distribution of thermal stresses is computed by solving heat transfer equations for varistor disks with nonuniform electrical properties. The simulations identify failure processes and determine energy absorption capability of varistor elements. The results are in excellent agreement with experiment and provide fundamental explanation of the energy handling dependence upon current surge intensity and duration. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Hubbell Power Syst, Centralia, MO 65240 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RP Bartkowiak, M (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Albe, Karsten/F-1139-2011 NR 16 TC 35 Z9 39 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 0885-8977 J9 IEEE T POWER DELIVER JI IEEE Trans. Power Deliv. PD JAN PY 1999 VL 14 IS 1 BP 152 EP 162 DI 10.1109/61.736708 PG 11 WC Engineering, Electrical & Electronic SC Engineering GA 151BJ UT WOS:000077700800022 ER PT B AU Dees, DW AF Dees, DW GP IEEE IEEE TI Overview of electrochemical power sources for electric and hybrid-electric vehicles SO IEMDC'99 - IEEE INTERNATIONAL ELECTRIC MACHINES AND DRIVES CONFERENCE, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Electric Machines and Drives Conference (IEMDC 99) CY MAY 09-12, 1999 CL SEATTLE, WA SP IEEE, IEEE, Power Engn Soc, IEEE, Ind Applicat Soc C1 Argonne Natl Lab, Electrochem Technol Program, Div Chem Technol, Argonne, IL 60439 USA. RP Dees, DW (reprint author), Argonne Natl Lab, Electrochem Technol Program, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5293-9 PY 1999 BP 258 EP 259 DI 10.1109/IEMDC.1999.769085 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA BN28R UT WOS:000081429300075 ER PT S AU Stach, EA Hull, R Tromp, RM Ross, FM Reuter, MC Bean, JC AF Stach, EA Hull, R Tromp, RM Ross, FM Reuter, MC Bean, JC BE Ringel, SA Fitzgerald, EA Adesida, I Houghton, DC TI Quantitative experimental determination of the effect of dislocation - Dislocation interactions on strain relaxation in lattice mismatched heterostructures SO III-V AND IV-IV MATERIALS AND PROCESSING CHALLENGES FOR HIGHLY INTEGRATED MICROELECTRONICS AND OPTOELECTRONICS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium D on Integration of Dissimilar Materials in Micro- and Optoelectronics / Symposium I on III-V and SiGe Group IV Device/IC Processing Challenges for Commercial Applications, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID MISFIT DISLOCATIONS; EPITAXIAL LAYER; GEXSI1-X/SI(100) HETEROSTRUCTURES; MULTILAYERS; VELOCITIES; SURFACE; DEFECTS; GLIDE; FILMS AB We present real time observations of the interaction of dislocations in heteroepitaxial strained layers using a specially modified ultrahigh vacuum transmission electron microscope equipped with in-situ deposition capabilities. These observations have led to delineation of the regime of epilayer thickness and composition where dislocation interactions result in blocking of the propagating threading segment. It is found that both the blocking probability as well as the magnitude of the dislocation interaction force are strongly dependent on the Burgers vectors of the dislocations involved, with the greatest effects observed when the Burgers vectors of the two dislocations are parallel with respect to each other. Frame-by-frame analysis of the motion of the dislocation threading segment during interaction is used to extract the magnitude of the interaction stresses as a function of both the level of heteroepitaxial strain and the dislocation geometry. Finally, by continuing growth following observations of blocking during annealing, we find that blocked dislocations are likely to remain in that configuration until substantial additional heteroepitaxial stresses are incorporated into the layer. These results have direct relevance to the successful integration of strained layer heterostructures into electronic device applications. This is because blocked threading segments result in the introduction of undesired band gap states, enhance impurity diffusion, modify surface morphology and act to limit the dislocation density reductions achievable in graded buffet structures. C1 Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Stach, EA (reprint author), Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RI Stach, Eric/D-8545-2011 OI Stach, Eric/0000-0002-3366-2153 NR 21 TC 0 Z9 0 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-441-6 J9 MATER RES SOC SYMP P PY 1999 VL 535 BP 15 EP 20 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BN69A UT WOS:000082590400003 ER PT S AU Fleming, JG Han, J AF Fleming, JG Han, J BE Ringel, SA Fitzgerald, EA Adesida, I Houghton, DC TI Growth of GaN on thin Si {111} layers bonded to Si {100} substrates SO III-V AND IV-IV MATERIALS AND PROCESSING CHALLENGES FOR HIGHLY INTEGRATED MICROELECTRONICS AND OPTOELECTRONICS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium D on Integration of Dissimilar Materials in Micro- and Optoelectronics / Symposium I on III-V and SiGe Group IV Device/IC Processing Challenges for Commercial Applications, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID SILICON AB We have demonstrated the ability to bond thin layers of Si{111} onto either silicon dioxide or silicon nitride coated Si{100}. This was achieved using a "Smart-Cut" process. The integration of SiN required chemical mechanical polishing. The growth of GaN on a thin Si{111} on oxide on Si{100} stack was demonstrated. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Fleming, JG (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-441-6 J9 MATER RES SOC SYMP P PY 1999 VL 535 BP 101 EP 106 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BN69A UT WOS:000082590400016 ER PT S AU Ashby, CIH AF Ashby, CIH BE Ringel, SA Fitzgerald, EA Adesida, I Houghton, DC TI Dynamics of wet oxidation of high-Al-content III-V materials SO III-V AND IV-IV MATERIALS AND PROCESSING CHALLENGES FOR HIGHLY INTEGRATED MICROELECTRONICS AND OPTOELECTRONICS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium D on Integration of Dissimilar Materials in Micro- and Optoelectronics / Symposium I on III-V and SiGe Group IV Device/IC Processing Challenges for Commercial Applications, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID SURFACE-EMITTING LASERS; VERTICAL-CAVITY LASERS; SELECTIVE OXIDATION; LATERAL OXIDATION; WATER-VAPOR; ALGAAS; OXIDE; GAAS; ALXGA1-XAS; LAYERS AB Oxidation of layers of high-Al-content III-V materials by water vapor has become the enabling process for high-efficiency vertical cavity surface emitting lasers (VCSELs) and has potential applications for reducing substrate current leakage in GaAs-on-insulator (GOI) MESFETs. Because of the established importance of wet oxidation in optoelectronic devices and its potential applications in electronic devices, it has become increasingly important to understand the mechanism of wet oxidation and how it might be expected to affect both the fabrication and subsequent operation of devices that have been made using this technique. The mechanism of wet oxidation and the consequence of this mechanism for heterostructure design and ultimate device operation are discussed here. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ashby, CIH (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 28 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-441-6 J9 MATER RES SOC SYMP P PY 1999 VL 535 BP 179 EP 188 PG 10 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BN69A UT WOS:000082590400028 ER PT S AU Windl, W Sankey, OF AF Windl, W Sankey, OF BE Ringel, SA Fitzgerald, EA Adesida, I Houghton, DC TI First-principles investigation of the ordered Si4C compound SO III-V AND IV-IV MATERIALS AND PROCESSING CHALLENGES FOR HIGHLY INTEGRATED MICROELECTRONICS AND OPTOELECTRONICS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium D on Integration of Dissimilar Materials in Micro- and Optoelectronics / Symposium I on III-V and SiGe Group IV Device/IC Processing Challenges for Commercial Applications, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID ELECTRONIC-STRUCTURE; MOLECULAR-DYNAMICS; CARBON ALLOYS; SI1-X-YGEXCY; GROWTH; STRAIN; PSEUDOPOTENTIALS; SEMICONDUCTORS; TRANSITION; GERMANIUM AB We have performed intensive theoretical studies on the ordered Si4C phase which has been proposed first by Rucker et al. [Phys. Rev. Lett. 72, 3578 (1994)] and which recently has been reportedly synthesized by Kouvetakis et al. [Appl. Phys. Lett. 72, 930 (1998)]. We calculate structural parameters which are significantly different from experimental values, and an IR spectrum with a peak position very similar to their experiment but a much narrower width. We suggest that the experimental findings might be consistent with the assumption of a system of Si4C sections/crystallites and other Si-C structures embedded in a Si matrix. C1 Univ Calif Los Alamos Natl Lab, Computat Mat Grp, Motorola Inc, Los Alamos, NM 87545 USA. RP Windl, W (reprint author), Univ Calif Los Alamos Natl Lab, Computat Mat Grp, Motorola Inc, MS B268, Los Alamos, NM 87545 USA. RI Windl, Wolfgang/C-7255-2012 OI Windl, Wolfgang/0000-0001-5892-0684 NR 28 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-441-6 J9 MATER RES SOC SYMP P PY 1999 VL 535 BP 299 EP 304 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BN69A UT WOS:000082590400045 ER PT B AU Barat, K AF Barat, K BE Dennis, J TI Laser safety audits, the question of frequency and type SO ILSC'99: PROCEEDINGS OF THE INTERNATIONAL LASER SAFETY CONFERENCE SE LASER INSTITUTE OF AMERICA - PROCEEDINGS LA English DT Proceedings Paper CT International Laser Safety Conference (ILSC 99) CY MAR 08-11, 1999 CL ORLANDO, FL SP Laser Inst Amer DE audits; laser safety; hazard evaluation AB A duty clearly called out in the ANSI Z136. 1 "Safe Use of Laser" standard is for the Laser Safety Officer[LSO] is to audit laser use areas to establish controls and for compliance with regulatory the ANSI standard and perform hazard evaluations. Unfortunate the standard gives little guidance on the frequency of these audits. This article attempts to give some guidance on the elements of an audit and how to determine the frequency. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Radiat Protect Grp, Berkeley, CA 94720 USA. RP Barat, K (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Radiat Protect Grp, Berkeley, CA 94720 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU LASER INST AMERICA PI ORLANDO PA 12424 RESEARCH PKWY, STE 130, ORLANDO, FL 32826 USA BN 0-912035-17-4 J9 LIA P PY 1999 VL 4 BP 369 EP 374 PG 6 WC Engineering, Biomedical; Public, Environmental & Occupational Health; Ophthalmology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Public, Environmental & Occupational Health; Ophthalmology; Radiology, Nuclear Medicine & Medical Imaging GA BN49H UT WOS:000082032700045 ER PT B AU Barat, KL AF Barat, KL BE Dennis, J TI Laser safety: When and how to do retraining SO ILSC'99: PROCEEDINGS OF THE INTERNATIONAL LASER SAFETY CONFERENCE SE LASER INSTITUTE OF AMERICA - PROCEEDINGS LA English DT Proceedings Paper CT International Laser Safety Conference (ILSC 99) CY MAR 08-11, 1999 CL ORLANDO, FL SP Laser Inst Amer AB The ANSI standard Z 136.1 "For Safe Use of Lasers" addresses training to the Laser Safety Officer[LSO], laser users, service staff and those working around lasers. This training requirement is re-enforced by all related regulatory agencies[OSHA, State programs]. The concept of retraining or refresher training is not broached in the standard. Refresher training is well established in the ionizing radiation arena. The purpose of re-training is to refresh the individual with laser safety principles and update them on new advances or procedures. This presentation address several approaches to provide re-training, i.e. computer based training, video tapes, testing out, lecture mode and literature handouts, and presents a suggested schedule for that re-training for each population group. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Radiat Protect Grp, Berkeley, CA 94720 USA. RP Barat, KL (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Radiat Protect Grp, Berkeley, CA 94720 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU LASER INST AMERICA PI ORLANDO PA 12424 RESEARCH PKWY, STE 130, ORLANDO, FL 32826 USA BN 0-912035-17-4 J9 LIA P PY 1999 VL 4 BP 420 EP 424 PG 5 WC Engineering, Biomedical; Public, Environmental & Occupational Health; Ophthalmology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Public, Environmental & Occupational Health; Ophthalmology; Radiology, Nuclear Medicine & Medical Imaging GA BN49H UT WOS:000082032700052 ER PT J AU Giraud, L Tuminaro, RS AF Giraud, L Tuminaro, RS TI Schur complement preconditioners for anisotropic problems SO IMA JOURNAL OF NUMERICAL ANALYSIS LA English DT Article ID ITERATIVE METHODS; ELLIPTIC PROBLEMS; DOMAIN DECOMPOSITION; SUBSTRUCTURES AB We present two new variants of Schur complement domain decomposition preconditioners suitable for 2D anisotropic problems. These variants are based on adaptations of the probing idea, described by Chan et al (1992 Fifth Int. Symp. on Domain Decomposition Methods for Partial Differential Equations, Philadelphia: SIAM, pp 236-249), used in conjunction with a coarse grid approximation as introduced by Bramble et al (1986 Math. Comput. 47, 103-134). The new methods are specifically designed for situations where the coupling between neighbouring interfaces is stronger than the coupling within an interface. Taking into account this strong coupling, one variant uses a multicolour probing technique to avoid distortion in the probe approximations that appear when using the method proposed by Chan et al. The second technique uses additional probe matrices to approximate not only the coupling within the interfaces but also the coupling between interface points across the subdomains. This latter procedure looks somewhat like an alternating line relaxation procedure and was motivated by the success of line relaxation within the multigrid method for anisotropic problems, see Brandt (1977 Math. Comput. 31, 333-390). To assess the relevance of the new preconditioners, we compare their numerical behaviour with well known robust preconditioners such as the balanced Neumann-Neumann method proposed by Mandel (1993 Commun. Numer Methods Eng. 9, 233-241). C1 CERFACS, Ctr Europeen Rech & Format Avancee Calcul Sci, F-31057 Toulouse, France. Sandia Natl Labs, Livermore, CA 94551 USA. RP CERFACS, Ctr Europeen Rech & Format Avancee Calcul Sci, 42 Ave G Coriolis, F-31057 Toulouse, France. NR 20 TC 8 Z9 8 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0272-4979 EI 1464-3642 J9 IMA J NUMER ANAL JI IMA J. Numer. Anal. PD JAN PY 1999 VL 19 IS 1 BP 1 EP 18 DI 10.1093/imanum/19.1.1 PG 18 WC Mathematics, Applied SC Mathematics GA 164ER UT WOS:000078450200001 ER PT S AU Barney, P Carne, T AF Barney, P Carne, T GP SPIE SPIE TI Modal parameter extraction using natural excitation response data SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB The use of natural excitation response data for the extraction of modal parameters has been an alluring idea for many years. The primary reason is that it offers the real world inputs (both spatial and temporal) and the associated responses of the system without the cost of a complex excitation system. The use of NExT allows for a linear representation of the system at operating levels, which is ideal for predictive linear simulation. The NExT parameter estimation methods have relied on using standard modal parameter extraction routines that do not exploit the special model form of NExT data. A parameter estimation method is developed here that is consistent with the form, thereby providing a more robust estimator in the presence of noise. This paper presents the basic methods used in NExT as well as some of the critical issues when using NExT. C1 Sandia Natl Labs, Expt Struct Dynam Dept, Albuquerque, NM 87185 USA. RP Barney, P (reprint author), Sandia Natl Labs, Expt Struct Dynam Dept, POB 5800, Albuquerque, NM 87185 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 49 EP 55 PG 7 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700008 ER PT S AU Farrar, CR Nix, DA Duffey, TA Cornwell, PJ Pardoen, GC AF Farrar, CR Nix, DA Duffey, TA Cornwell, PJ Pardoen, GC GP SPIE SPIE TI Damage identification with linear discriminant operators SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB This paper explores the application of statistical pattern recognition and machine learning techniques to vibration-based damage detection. First, the damage detection process is described in terms of a problem in statistical pattern recognition. Next, a specific example of a statistical-pattern-recognition-based damage detection process using a linear discriminant operator, "Fisher's Discriminant: is applied to the problem of identifying structural damage in a physical system. Accelerometer lime histories are recorded from sensors attached to the system as that system is excited using a measured input. Linear Prediction Coding (LPC) coefficients are utilized to convert the accelerometer time-series data into multi-dimensional samples representing the resonances of the system during a brief segment of the time series. Fisher's discriminant is then used to find the linear projection of the LPC data distributions that best separates data from undamaged and damaged systems. The method is applied to data from concrete bridge columns as the columns are progressively damaged. For this case, the method captures a clear distinction between undamaged and damaged vibration profiles. Further, the method assigns a probability of damage that can be used to rank systems in order of priority for inspection. C1 Univ Calif Los Alamos Natl Lab, Engn Anal Grp, Los Alamos, NM 87545 USA. RP Farrar, CR (reprint author), Univ Calif Los Alamos Natl Lab, Engn Anal Grp, MS P946, Los Alamos, NM 87545 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 599 EP 607 PG 9 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700093 ER PT S AU Farrar, CR Duffey, TA Cornwell, PJ Bement, MT AF Farrar, CR Duffey, TA Cornwell, PJ Bement, MT GP SPIE SPIE TI A review of methods for developing accelerated testing criteria SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB Accelerated vibration testing seeks to compress long service exposures to vibration into a reduced length laboratory test by increasing the amplitude and/or frequency of the applied inputs during the laboratory test relative to the amplitude and/or frequency experienced during service. This testing procedure provides an important tool that can reduce testing time associated with a new design and reduce time to market. This paper will summarize current methods that are employed to develop accelerated testing criteria and will highlight the attributes and limitations of these methods. Typically there are two ways of accelerating vibration testing. The first method involves testing at fewer cycles but at higher amplitude levels; and the second method involves testing at higher frequencies (rates). A combination of the two is also an option. Development of an accelerated test based on either of these methods requires a priori knowledge of the controlling failure mechanisms. The review will begin with a discussion of Miner's Rule for developing accelerated testing criteria. This rule, which is based on a linear damage accumulation assumption, was first proposed in the 1940's for fatigue failures of ductile metals loaded repetitively in bending. Confounding factors associated with developing accelerated testing criteria for nonlinear vibration response (e.g., rattling of components) will be illustrated with an example. C1 Univ Calif Los Alamos Natl Lab, Engn Anal Grp, Los Alamos, NM 87545 USA. RP Farrar, CR (reprint author), Univ Calif Los Alamos Natl Lab, Engn Anal Grp, MS P946, Los Alamos, NM 87545 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 608 EP 614 PG 7 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700094 ER PT S AU Mayes, RL Klenke, SE AF Mayes, RL Klenke, SE GP SPIE SPIE TI The SMAC modal parameter extraction package SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB The objective of many modal testing programs is to identify modal parameters of complex systems for model validation purposes. Often this objective is difficult to achieve in an efficient manner due to the complexity of the system being tested. Traditional modal extraction techniques perform well under certain conditions; however, when moderately damped modes and/or high modal density is characteristic of the system response, accurate identification of the modal parameters is challenging. A modal extraction package, call ed "Synthesize Modes and Correlate" or SMAC, has been developed to address these concerns. This extraction technique calculates reciprocal modal Vectors based on frequency response function (FRF) measurements. The FRFs are multiplied by a reciprocal modal vector to synthesize a single degree-of-freedom (SDOF) FRF. The correlation coefficient compares the synthesized SDOF FRF against an analytical SDOF FRF. Frequency and damping values are optimized to obtain the maximum correlation coefficient, which corresponds to the true system root. A quadrature fit algorithm is then used to generate shapes based on the SMAC modal parameters. Examples are provided utilizing the SMAC package on experimental data from a moderately damped system and one with high-modal density. C1 Sandia Natl Labs, Expt Struct Dynam Dept, Albuquerque, NM 87185 USA. RP Mayes, RL (reprint author), Sandia Natl Labs, Expt Struct Dynam Dept, POB 5800, Albuquerque, NM 87185 USA. NR 12 TC 3 Z9 3 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 812 EP 818 PG 7 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700126 ER PT S AU Hunter, NF AF Hunter, NF GP SPIE SPIE TI Bilinear system characteristics from nonlinear time series analysis SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB Detection of changes in the resonant frequencies and mode shapes of a system is a fundamental problem in dynamics. This paper describes a time series method of detecting and quantifying changes in these parameters for a ten degree-of-freedom bilinear system excited by narrow band random noise. The method partitions the state space and computes mode frequencies and mode shapes for each region. Different regions of the space may exhibit different mode shapes, allowing diagnosis of stiffness changes at structural discontinuities. The method is useful for detecting changes in the properties of joints in mechanical systems or for detection of damage as the properties of a structure change during use. C1 Univ Calif Los Alamos Natl Lab, Engn Sci & Applicat Div, Los Alamos, NM 87545 USA. RP Hunter, NF (reprint author), Univ Calif Los Alamos Natl Lab, Engn Sci & Applicat Div, Mail Stop C-931, Los Alamos, NM 87545 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 1488 EP 1494 PG 7 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700227 ER PT S AU Paez, T Hunter, N Red-Horse, J AF Paez, T Hunter, N Red-Horse, J GP SPIE SPIE TI Statistical tests of system linearity based on method of surrogate data SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc ID TIME-SERIES AB When dealing with measured data from dynamic systems we often make the tacit assumption that the data are generated by linear dynamics. While some systematic tests for linearity and determinism are available (for example the coherence function, the probability density function, and the bispectrum), further tests which quantify the existence and the degree of nonlinearity are clearly needed. In this paper we demonstrate a statistical test for the nonlinearity exhibited by a dynamic system excited by Gaussian random noise. We perform the usual division of the input and response time series data into blocks as required by the Welch method of spectrum estimation and search for significant relationships between a given input frequency and response at harmonics of the selected input frequency. We argue that systematic tests based on the recently developed statistical method of surrogate data readily detect significant nonlinear relationships. The paper elucidates the method of surrogate data. Typical results are illustrated for a linear single degree of freedom system and for a system with polynomial stiffness nonlinearity. C1 Sandia Natl Labs, Expt Struct Dynam Dept, Albuquerque, NM 87185 USA. RP Paez, T (reprint author), Sandia Natl Labs, Expt Struct Dynam Dept, 9199 Mail Stop 0557, Albuquerque, NM 87185 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 1495 EP 1500 PG 6 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700228 ER PT S AU Hemez, FM Doebling, SW AF Hemez, FM Doebling, SW GP SPIE SPIE TI Test-analysis correlation and finite element model updating for nonlinear, transient dynamics SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB This research aims at formulating criteria for measuring the correlation between test data and finite element results for nonlinear, transient dynamics. After reviewing the linear case and illustrating the limitations of modal-based updating when it is applied to nonlinear experimental data, simple time-domain, test-analysis correlation metrics are proposed. Two implementations are compared: the conventional least-squares technique and the Principal Component Decomposition that correlates subspaces rather than individual time-domain responses. Illustrations and discussions are provided using the LANL 8-DOF system, an experimental testbed for validating nonlinear data correlation and model updating techniques. C1 Univ Calif Los Alamos Natl Lab, ESA, Engn Anal Grp, Los Alamos, NM 87545 USA. RP Hemez, FM (reprint author), Univ Calif Los Alamos Natl Lab, ESA, Engn Anal Grp, MS P946, Los Alamos, NM 87545 USA. NR 18 TC 0 Z9 0 U1 1 U2 1 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 1501 EP 1510 PG 10 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700229 ER PT S AU Hemez, FM Doebling, SW AF Hemez, FM Doebling, SW GP SPIE SPIE TI A validation of Bayesian finite element model updating for linear dynamics SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc ID METHODOLOGY AB This work addresses the issue of statistical model updating and correlation. The updating procedure is formulated to improve the predictive quality of a structural model by minimizing out-of-balance modal forces. it is shown how measurement and modeling uncertainties can be taken into account to provide not only the correlated model but also the associated confidence levels. Hence, a Bayesian parameter estimation technique is derived and its numerical implementation is discussed. Two demonstration examples that involve test-analysis correlation with real test data are presented. First, the validation of an engine cradle model used in the automotive industry shows how the design's uncertainties can be reduced via model updating. Our second example consists of employing test-analysis correlation for identifying the degree of nonlinearity of the LANL 8-DOF testbed. C1 Univ Calif Los Alamos Natl Lab, ESA, Engn Anal Grp, Los Alamos, NM 87545 USA. RP Hemez, FM (reprint author), Univ Calif Los Alamos Natl Lab, ESA, Engn Anal Grp, MS P946, Los Alamos, NM 87545 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 1545 EP 1555 PG 11 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700235 ER PT S AU Bir, G Stol, K AF Bir, G Stol, K GP SPIE SPIE TI Operating modes of a teetered-rotor wind turbine SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB We examine the operating modes of a two-bladed teetered wind turbine the dynamics of which, because of the gyroscopic asymmetry of its rotor, can be quite distinct from the dynamics of a turbine with three or more blades. This asymmetry leads to system equations with periodic coefficients that are served using the Floquet approach to extract the correct modal parameters. The system equations are derived using a simple analytical model with four degrees of freedom: nacelle yaw, rotor teeter, and flapping associated with each blade. Results confirm that the turbine modes become more dominated by the centrifugal and gyroscopic effects as the rotor speed increases. The gyroscopic effect may also cause dynamically instability. Under certain design conditions, yaw and teeter modal frequencies may coalesce. C1 Natl Renewable Energy Lab, Natl Wind Technol Ctr, Golden, CO 80401 USA. RP Bir, G (reprint author), Natl Renewable Energy Lab, Natl Wind Technol Ctr, 1617 Cole Blvd, Golden, CO 80401 USA. OI Stol, Karl/0000-0002-1661-167X NR 13 TC 1 Z9 1 U1 0 U2 1 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 1586 EP 1596 PG 11 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700240 ER PT S AU Simmermacher, T Mayes, R AF Simmermacher, T Mayes, R GP SPIE SPIE TI Laboratory simulation of response to a distributed pressure load SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB Responses to a distributed pressure load are typically predicted through the use of a finite-element model. This procedure depends on the model to represent the actual structure accurately. Another technique that is developed in this work is to predict the response based upon an experimentally derived model. This model consists of frequency response functions. The pressure distribution is assumed to be known. In this work, the pressure load will be a blast load. The focus of this work will be to simulate a harsh, shock-like environment. Data from a reverse Hopkinson bar (RHB) test is used to generate the response to a symmetric, distributed load. The reverse Hopkinson bar generates a high amplitude, high frequency content pulse that excites components at near-blast levers. The frequency response functions generated from the RHB are used to generate an experimental model of the structure, which is then used in conjunction with the known pressure distribution, to estimate the component response to a blast. This result can then be used with a model correlation technique to adjust a finite element model such that data from a true blast test can be used to only fine tune the model. This work details the estimation of the response due to the blast. C1 Sandia Natl Labs, Albuquerque, NM 87111 USA. RP Simmermacher, T (reprint author), Sandia Natl Labs, POB 1800, Albuquerque, NM 87111 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 1640 EP 1645 PG 6 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700247 ER PT S AU Fleld, RV Paez, TL Red-Horse, JR AF Fleld, RV Paez, TL Red-Horse, JR GP SPIE SPIE TI Utilizing Gauss-Hermite quadrature to evaluate uncertainty in dynamic system SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB Probabilistic uncertainty is a phenomenon that occurs to a certain degree in many engineering applications. The effects that this uncertainty has upon a given system response is a matter of some concern. Techniques which provide insight to these effects will be required as modeling and prediction become a more vital tool in the engineering design process. As might be expected, this is a difficult proposition and the focus of many research efforts. The purpose of this paper is to outline a procedure to evaluate uncertainty in dynamic system response exploiting Gauss-Hermite numerical quadrature. Specifically, numerical integration techniques are utilized in conjunction with the Advanced Mean Value (AMV) method to efficiently and accurately estimate moments of the response process. A numerical example illustrating the use of this analytical tool in a practical framework is presented. C1 Sandia Natl Labs, Struct Dynam & Control Dept 9234, Albuquerque, NM 87185 USA. RP Fleld, RV (reprint author), Sandia Natl Labs, Struct Dynam & Control Dept 9234, MS 0439, Albuquerque, NM 87185 USA. RI Field, Richard/K-6468-2013 OI Field, Richard/0000-0002-2765-7032 NR 8 TC 0 Z9 0 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 1856 EP 1861 PG 6 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700280 ER PT S AU Jorgensen, BR Woehrle, T Eli, M Chow, CT AF Jorgensen, BR Woehrle, T Eli, M Chow, CT GP SPIE SPIE TI Modal response of interior mass based upon external measurements SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB Modal response testing has been used to predict the motion of interior masses of a system in which only external instrumentation is allowed. Testing of this form may occasionally be necessary in validation of a computer model, but also has potential as a tool for validating individual assemblies in a QA process. Examination of the external frequency response and mode shapes can offer insight into interior response. The interpretation of these results is improved through parallel analytical solutions. A simple, three-mass model has been examined experimentally and analytically to demonstrate modal theory. These results show the limitations of the external measurement in predicting internal response due to transmissibility. A procedure for utilizing external testing is described. The question posed through this research is whether or not modal correlation analysis can be adapted for use in systems for which instrumentation of critical components is missing. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Jorgensen, BR (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 2038 EP 2041 PG 4 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700306 ER PT S AU Red-Horse, JR Ghanem, R AF Red-Horse, JR Ghanem, R GP SPIE SPIE TI Uncertainty propagation using a Stochastic Finite Element approach SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB The present study focuses on the development of a general framework for propagating the effects of parametric uncertainty; modeled as random fields: from input to output for complex engineering systems via Stochastic Finite Element techniques. These techniques are similar in concept to deterministic finite element approaches in that they approximate both input and output quantities in terms of finite dimensional series expansions and exploit orthogonality relationships to arrive at equations for associated system unknowns. In the stochastic case, the input quantities are random fields with probabilistic or statistical descriptions that are assumed to be obtainable. The inner products are mathematical expectations. A major advantage of the approach is its ability to be implemented as an external loop around deterministic analytical codes. Thus, the approach is a reasonable extension to current traditional deterministic simulations. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Red-Horse, JR (reprint author), Sandia Natl Labs, POB 5800,MS0439, Albuquerque, NM 87185 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 2072 EP 2077 PG 6 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700312 ER PT S AU Ludowise, PD Ottesen, DK Kulp, TJ Goers, UB AF Ludowise, PD Ottesen, DK Kulp, TJ Goers, UB BE Descour, MR Shen, SS TI A PPLN laser-based system for chemical imaging SO IMAGING SPECTROMETRY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry V CY JUL 19-21, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE chemical imaging; cleaning verification; reflectance spectroscopy; cw OPO; PPLN ID BACKSCATTER AB An infrared-imaging instrument is being developed to provide in situ qualitative and quantitative assessment of hydrocarbon contaminants on metallic surfaces for cleaning verification. A continuous-wave infrared optical parametric oscillator (OPO), based on the quasi-phasematched material periodically poled lithium niobate (PPLN), is interfaced with an InSb focal plane array camera to perform fast, non-invasive analysis by reflectance spectroscopy. The period range of the designed fan-out PPLN crystal determines the range of the output wavelength of the light source. It is able to scan hundreds of wavenumbers positioned in the range of 2820 - 3250 cm(-1), which is sufficient to detect functional groups of common organic compounds (-CH, -OH, and -NH). The capability of the instrument has been demonstrated in a preliminary investigation of reflectance measurements for hydrocarbon solvents (methanol and d-limonene) on an aluminum surface. A substantial difference in absorption is obtained for the two solvents at two different laser-illumination wavelengths, thus permitting hydrocarbon detection and molecular species differentiation. Preliminary reflectance spectra of a mixture of aliphatic hydrocarbon lubricants and drawing agents on an aluminum panel are also presented. The relative thickness of the hydrocarbon thin film is determined by the intensity ratio of images acquired at two different laser illumination frequencies. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Ludowise, PD (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3239-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3753 BP 51 EP 60 DI 10.1117/12.366314 PG 10 WC Engineering, Aerospace; Geosciences, Multidisciplinary; Remote Sensing; Optics; Spectroscopy SC Engineering; Geology; Remote Sensing; Optics; Spectroscopy GA BP12B UT WOS:000084180200006 ER PT S AU Weber, PG Brock, BC Garrett, AJ Smith, BW Borel, CC Clodius, WB Bender, SC Kay, RR Decker, ML AF Weber, PG Brock, BC Garrett, AJ Smith, BW Borel, CC Clodius, WB Bender, SC Kay, RR Decker, ML BE Descour, MR Shen, SS TI Multispectral thermal imager mission overview. SO IMAGING SPECTROMETRY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry V CY JUL 19-21, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE modeling; analysis; system design; multispectral imaging; calibration; satellite; space-borne imaging spectroscopy AB The Multispectral Thermal Imager (MTI) is a research and development project sponsored by the Department of Energy and executed by Sandia and Los Alamos National Laboratories and the Savannah River Technology Center. Other participants include the U. S. Air Force, universities, and many industrial partners. The MTI mission is to demonstrate the efficacy of highly accurate multispectral imaging for passive characterization of industrial facilities and related environmental impacts from space. MTI provides simultaneous data for atmospheric characterization at high spatial resolution. Additionally, MTI has applications to environmental monitoring and other civilian applications. The mission is based in end-to-end modeling of targets, signatures, atmospheric effects,the space sensor, and analysis techniques to form a balanced, self-consistent mission. The MTI satellite nears completion, and is scheduled for launch in late 1999. This. paper describes the MTI mission, development of desired system attributes, some trade studies, schedule, and overall plans for data acquisition and analysis. This effort drives the sophisticated payload and advanced calibration systems, which are the overall subject of the first session at this conference, as well as the data processing and some of the analysis tools that will be described in the second segment. C1 Univ Calif Los Alamos Natl Lab, Space & Remote Sci Grp, Los Alamos, NM 87545 USA. RP Weber, PG (reprint author), Univ Calif Los Alamos Natl Lab, Space & Remote Sci Grp, MS D436, Los Alamos, NM 87545 USA. NR 18 TC 15 Z9 15 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3239-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3753 BP 340 EP 346 DI 10.1117/12.366296 PG 7 WC Engineering, Aerospace; Geosciences, Multidisciplinary; Remote Sensing; Optics; Spectroscopy SC Engineering; Geology; Remote Sensing; Optics; Spectroscopy GA BP12B UT WOS:000084180200035 ER PT S AU Kay, RR Bender, SC Henson, TD Byrd, DA Rienstra, JL Decker, ML Rackley, NG Akau, RL Claassen, PJ Kidner, RE Taplin, RB Bullington, DM Marbach, KD Lanes, CE Little, C Smith, BW Brock, BC Weber, PG AF Kay, RR Bender, SC Henson, TD Byrd, DA Rienstra, JL Decker, ML Rackley, NG Akau, RL Claassen, PJ Kidner, RE Taplin, RB Bullington, DM Marbach, KD Lanes, CE Little, C Smith, BW Brock, BC Weber, PG BE Descour, MR Shen, SS TI Multispectral thermal imager (MTI) payload overview SO IMAGING SPECTROMETRY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry V CY JUL 19-21, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE multispectral; infrared; visible; imager; radiometry; calibration; image compression; satellite AB MTI is a comprehensive research and development project that includes up-front modeling and analysis, satellite system design, fabrication, assembly and testing, on-orbit operations, and experimentation and data analysis. The satellite is designed to collect radiometrically calibrated, medium resolution imagery in 15 spectral bands ranging from 0.45 to 10.70 mu m. The payload portion of the satellite includes the imaging system components, associated electronics bares, and payload support structure. The imaging system includes a three-mirror anastigmatic off-axis telescope, a single cryogenically cooled focal plane assembly, a mechanical cooler, and an onboard calibration system. Payload electronic subsystems include image digitizers, real-time image compressors, a solid I;tate recorder, calibration source drivers, and cooler temperature and vibration controllers. The payload support structure mechanically integrates all payload components and provides a simple four point interface to the spacecraft bus. All payload components have been, fabricated and rested, and integrated. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Kay, RR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 1 TC 14 Z9 14 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3239-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3753 BP 347 EP 358 DI 10.1117/12.366297 PG 12 WC Engineering, Aerospace; Geosciences, Multidisciplinary; Remote Sensing; Optics; Spectroscopy SC Engineering; Geology; Remote Sensing; Optics; Spectroscopy GA BP12B UT WOS:000084180200036 ER PT S AU Henson, T Krumel, L Blake, D Bender, S Byrd, D Christensen, W Rappoport, W Shen, GY AF Henson, T Krumel, L Blake, D Bender, S Byrd, D Christensen, W Rappoport, W Shen, GY BE Descour, MR Shen, SS TI Multispectral Thermal Imager Optical Assembly performance and integration of the flight Focal Plane Assembly SO IMAGING SPECTROMETRY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry V CY JUL 19-21, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE multispectral imaging; remote sensing; space optics ID MULTIBAND IMAGING-SYSTEM AB The Multispectral Thermal Imager Optical Assembly (OA) has been fabricated, assembled, successfully performance tested, and integrated into the flight payload structure with the flight Focal Plane Assembly (FPA) integrated and aligned to it. This represents a major milestone achieved towards completion of this earth observing E-O imaging sensor that is to be operated in low earth orbit. The OA consists of an off-axis three mirror anastigmatic (TMA) telescope with a 36 cm unobscured clear aperture, a wide-field-of-view (WFOV) of 1.82 degrees along the direction of spacecraft motion and 1.38 degrees across the direction of spacecraft motion. It also contains a comprehensive on-board radiometric calibration system. The OA is part of a multispectral pushbroom imaging sensor which employs a single mechanically cooled focal plane with 15 spectral bands covering a wavelength range from 0.45 to 10.7 mu m. The OA achieves near diffraction-limited performance from visible to the long-wave infrared (LWIR) wavelengths. The two major design drivers for the OA are 80% enpixeled energy in the visible bands and radiometric stability. Enpixeled energy in the visible bands also drove the alignment of the FPA detectors to the OA image plane to a requirement of less than +/- 20 mu m over the entire visible detector field of view (FOV). Radiometric stability requirements mandated a cold Lyot stop for stray light rejection and thermal background reduction. The Lyot stop is part of the FPA assembly and acts as the aperture stop for the imaging system. The alignment of the Lyot stop to the OA drove the centering and to some extent the tilt alignment requirements of the FPA to the OA. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Henson, T (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 9 TC 5 Z9 5 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3239-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3753 BP 359 EP 368 DI 10.1117/12.366298 PG 10 WC Engineering, Aerospace; Geosciences, Multidisciplinary; Remote Sensing; Optics; Spectroscopy SC Engineering; Geology; Remote Sensing; Optics; Spectroscopy GA BP12B UT WOS:000084180200037 ER PT S AU Rienstra, JL Ballard, M AF Rienstra, JL Ballard, M BE Descour, MR Shen, SS TI MTI focal plane assembly design and performance SO IMAGING SPECTROMETRY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry V CY JUL 19-21, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE multispectral imaging; focal plane arrays; remote sensing AB The focal plane assembly for the Multispectral Thermal Imager (MTI) consists of sensor chip assemblies, optical filters, and a vacuum enclosure. Sensor chip assemblies, composed of linear detector arrays and readout integrated circuits, provide spatial resolution in the cross-track direction for the pushbroom imager. Optical filters define 15 spectral bands in a range from 0.45 mu m to 10.7 mu m. All the detector arrays are mounted on a single focal plane and are designed to operate at 75 K. Three pairs of sensor chip assemblies (SCAs) are required to provide cross-Crack coverage in all 15 spectral bands. Each pair of SCAs includes detector arrays made from silicon, indium antimonide, and mercury cadmium telluride. Readout integrated circuits multiplex the signals from the detectors to 18 separate video channels. Optical filter assemblies defining the spectral bands are mounted over the linear detector arrays. Each filter assembly consists of several filter strips bonded together side-by-side. The MTI focal plane assembly has been integrated with the rest of the payload and has undergone detailed testing and calibration. This paper includes representative rest data for the various spectral bands and the overall performance of the focal plane assembly. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Rienstra, JL (reprint author), Sandia Natl Labs, POB 5800,MS 0972, Albuquerque, NM 87185 USA. NR 4 TC 10 Z9 10 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3239-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3753 BP 369 EP 379 DI 10.1117/12.366299 PG 11 WC Engineering, Aerospace; Geosciences, Multidisciplinary; Remote Sensing; Optics; Spectroscopy SC Engineering; Geology; Remote Sensing; Optics; Spectroscopy GA BP12B UT WOS:000084180200038 ER PT S AU Clodius, WB Bender, SC Kay, RR Smith, BW Atkins, WH Christensen, W Little, CK Zalewski, EF Rappoport, WM AF Clodius, WB Bender, SC Kay, RR Smith, BW Atkins, WH Christensen, W Little, CK Zalewski, EF Rappoport, WM BE Descour, MR Shen, SS TI MTI on-orbit calibration SO IMAGING SPECTROMETRY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry V CY JUL 19-21, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE multispectral; satellite; image; calibration; thermal; infrared; visible ID MANUFACTURE; STANDARD AB The Multi-spectral Thermal Imager (MTI) will be a satellite-based imaging system that will provide images in fifteen spectral bands covering large portions of the spectrum from 0.45 through 10.7 microns. An important goal of the mission is to provide data with state-of-the-art radiometric calibration. The on-orbit calibration will rely on the pre-launch ground calibration and will be maintained by vicarious calibration campaigns, System drifts before and between the vicarious calibration campaigns will be monitored by several on-board sources that serve as transfer sources in the calibration of external images;These sources can be divided into two groups: a set of sources at an internal aperture, primarily intended to monitor short term drifts in the detectors and associated electronics; and two sources at the external aperture, intended to monitor longer term drifts in the optical train before the internal aperture. The steps needed to transfer calibrations to image products, additional radiometric data quality estimates performed as part of this transfer, and the data products associated with this transfer will all be examined. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Clodius, WB (reprint author), Univ Calif Los Alamos Natl Lab, MS C323, Los Alamos, NM 87545 USA. NR 13 TC 6 Z9 6 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3239-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3753 BP 380 EP 391 DI 10.1117/12.366300 PG 12 WC Engineering, Aerospace; Geosciences, Multidisciplinary; Remote Sensing; Optics; Spectroscopy SC Engineering; Geology; Remote Sensing; Optics; Spectroscopy GA BP12B UT WOS:000084180200039 ER PT S AU Szymanski, JJ Borel, CC Clodius, WB Davis, AB Heil, CE Krone, JB Ramsey, K Smith, BW Smith, K Theiler, J Villeneuve, PV Weber, PG AF Szymanski, JJ Borel, CC Clodius, WB Davis, AB Heil, CE Krone, JB Ramsey, K Smith, BW Smith, K Theiler, J Villeneuve, PV Weber, PG BE Descour, MR Shen, SS TI MTI ground data processing and science retrieval pipeline architecture SO IMAGING SPECTROMETRY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry V CY JUL 19-21, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE data processing centers; multispectral analysis; remote sensing algorithms; thermal infrared AB The major science goal for the Multispectral Thermal Imager (MTI) project is to measure surface properties such as vegetation health, temperatures, material composition and others for characterization of industrial facilities and environmental applications. To support this goal, this program has several coordinated components, including modeling, comprehensive ground-truth measurements, image acquisition planning, data processing and data interpretation. Algorithms have been developed to retrieve a multitude of physical quantities and these algorithms are integrated in a processing pipeline architecture that emphasizes automation, flexibility and robust operation. In addition, the MTI science team has produced detailed site, system and atmospheric medals to aid in system design and data analysis. This paper will provide an introduction to the data processing and science algorithms for the MTI project. Detailed discussions of the retrieval techniques will follow in papers from the balance. of this session. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Szymanski, JJ (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop C323, Los Alamos, NM 87545 USA. NR 5 TC 6 Z9 6 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3239-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3753 BP 394 EP 402 DI 10.1117/12.366301 PG 9 WC Engineering, Aerospace; Geosciences, Multidisciplinary; Remote Sensing; Optics; Spectroscopy SC Engineering; Geology; Remote Sensing; Optics; Spectroscopy GA BP12B UT WOS:000084180200040 ER PT S AU Borel, CC Clodius, WB Davis, AB Smith, BW Szymanski, JJ Theiler, J Villeneuve, PV Weber, PG AF Borel, CC Clodius, WB Davis, AB Smith, BW Szymanski, JJ Theiler, J Villeneuve, PV Weber, PG BE Descour, MR Shen, SS TI MTI core science retrieval algorithms SO IMAGING SPECTROMETRY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry V CY JUL 19-21, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc AB The Multispectral Thermal Imager (MTI) has a number of core science retrievals which will be described. We will concentrate on describing the major Level-2 algorithms which, cover land, water and atmospheric products. The land products comprise atmospherically corrected surface reflectances, vegetation health status, material identification, land temperature and emissivities. The water related products are: water mask, water quality and water temperature. The atmospheric products are: cloud mask, cirrus mask and atmospheric water vapor. We will present several of these algorithms and present results from simulated MTI data derived from AVIRIS and MODIS Airborne Simulator (MAS). An interactive analysis tool has been created to visually program and test certain Level-2 retrievals. C1 Univ Calif Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, Los Alamos, NM 87545 USA. RP Borel, CC (reprint author), Univ Calif Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, Mailstop C 323, Los Alamos, NM 87545 USA. NR 19 TC 6 Z9 6 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3239-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3753 BP 403 EP 415 DI 10.1117/12.366302 PG 13 WC Engineering, Aerospace; Geosciences, Multidisciplinary; Remote Sensing; Optics; Spectroscopy SC Engineering; Geology; Remote Sensing; Optics; Spectroscopy GA BP12B UT WOS:000084180200041 ER PT S AU Theiler, J Harvey, NR Brumby, SP Szymanski, JJ Alferink, S Perkins, S Porter, R Bloch, JJ AF Theiler, J Harvey, NR Brumby, SP Szymanski, JJ Alferink, S Perkins, S Porter, R Bloch, JJ BE Descour, MR Shen, SS TI Evolving retrieval algorithms with a genetic programming scheme SO IMAGING SPECTROMETRY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry V CY JUL 19-21, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE remote sensing; retrieval algorithms; image processing; genetic algorithms; genetic programming AB The retrieval of scene properties (surface temperature, material type, vegetation health, etc.) from remotely sensed data is the ultimate goal of many earth observing satellites. The algorithms that have been developed for these retrievals are informed by physical models of how the raw data were generated. This includes models of radiation as emitted and/or reflected by the scene, propagated through the atmosphere, collected by the optics, detected by the sensor, and digitized by the electronics. To some extent, the retrieval is the inverse of this "forward" modeling problem. But in contrast to this forward modeling, the practical task of making inferences about the original scene usually requires some ad hoc assumptions, good physical intuition, and a healthy dose of trial and error. The standard MTI data processing pipeline will employ algorithms developed with this traditional approach. But we will discuss some preliminary research on the use of a genetic programming scheme to "evolve" retrieval algorithms. Such a scheme cannot compete with the physical intuition of a remote sensing scientist, but it may be able to automate some of the trial and error. In this scenario, a training set is used, which consists of multispectral image, data and the associated "ground truth;" that is, a registered map of the desired retrieval quantity. The genetic programming scheme attempts to combine a core set of image processing primitives to produce an IDL (Interactive Data Language) program which estimates this retrieval quantity from the raw data. C1 Univ Calif Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, Los Alamos, NM 87545 USA. RP Theiler, J (reprint author), Univ Calif Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, POB 1663, Los Alamos, NM 87545 USA. NR 18 TC 22 Z9 22 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3239-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3753 BP 416 EP 425 DI 10.1117/12.366303 PG 10 WC Engineering, Aerospace; Geosciences, Multidisciplinary; Remote Sensing; Optics; Spectroscopy SC Engineering; Geology; Remote Sensing; Optics; Spectroscopy GA BP12B UT WOS:000084180200042 ER PT S AU Stallard, BR Taylor, JG AF Stallard, BR Taylor, JG BE Descour, MR Shen, SS TI Quantifying multivariate classification performance - the problem of overfitting SO IMAGING SPECTROMETRY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry V CY JUL 19-21, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE imaging spectrometry; multivariate classification; overfitting AB We have been studying the use of spectral imagery to locate targets in spectrally interfering backgrounds. In making performance estimates for various sensors it has become evident that some calculations are unreliable because of overfitting. Hence, we began a thorough study of the problem of overfitting in multivariate classification. In this paper we present some model based results describing the problem, From the model we know the ideal covariance matrix, the ideal discriminant vector, and the ideal classification performance, We then investigate how experimental conditions such as noise, number of bands, and number of samples cause discrepancies from the ideal results. We also suggest ways to discover and alleviate overfitting. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Stallard, BR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3239-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3753 BP 426 EP 436 DI 10.1117/12.366304 PG 11 WC Engineering, Aerospace; Geosciences, Multidisciplinary; Remote Sensing; Optics; Spectroscopy SC Engineering; Geology; Remote Sensing; Optics; Spectroscopy GA BP12B UT WOS:000084180200043 ER PT S AU Garrett, AJ Kurzeja, RJ O'Steen, BL Parker, MJ Pendergast, MM Villa-Aleman, E AF Garrett, AJ Kurzeja, RJ O'Steen, BL Parker, MJ Pendergast, MM Villa-Aleman, E BE Descour, MR Shen, SS TI Post-launch validation of Multispectral Thermal Imager (MTI) data and algorithms SO IMAGING SPECTROMETRY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry V CY JUL 19-21, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE validation; verification; ground truth; multispectral imaging AB Sandia National Laboratories (SNL), Los Alamos National Laboratory (LANL) and the Savannah River Technology Center (SRTC) have developed a diverse: group of algorithms for processing and analyzing the data that will be collected by the Multispectral Thermal Imager (MTI) after launch late in 1999. Each of these algorithms must be verified by comparison to independent surface and atmospheric measurements. SRTC has selected 13 sites in the continental U.S. far ground truth data collections, These sites include a high altitude cold water target (Crater Lake), cooling lakes and towers in the warm, humid southeastern US, Department of Energy (DOE) climate research sites, the NASA Stennis satellite Validation and Verification (V&V) target array, waste sites at the Savannah River Site, mining sites in the Four Corners area and dry lake beds in Nevada. SRTC has established mutually beneficial relationships with the organizations that manage these sites to make use of their operating and research data and to install additional instrumentation needed for MTI algorithm V&V. C1 Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Garrett, AJ (reprint author), Savannah River Technol Ctr, Aiken, SC 29808 USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3239-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3753 BP 437 EP 448 DI 10.1117/12.366305 PG 12 WC Engineering, Aerospace; Geosciences, Multidisciplinary; Remote Sensing; Optics; Spectroscopy SC Engineering; Geology; Remote Sensing; Optics; Spectroscopy GA BP12B UT WOS:000084180200044 ER PT S AU Pennycook, SJ Nellist, PD AF Pennycook, SJ Nellist, PD BE Rickerby, DG Valdre, G Valdre, U TI Z-contrast scanning transmission electron microscopy SO IMPACT OF ELECTRON AND SCANNING PROBE MICROSCOPY ON MATERIALS RESEARCH SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES E, APPLIED SCIENCES LA English DT Proceedings Paper CT Conference of the NATO Advanced Study Institute on Impact of Electron and Scanning Probe Microscopy on Materials Research CY APR 14-25, 1998 CL ERICE, ITALY SP NATO Sci Affairs Div, European Commiss DG XII, TMR Program, Univ Italian Minist & Sci Res, Sicilian Region Govt, Ettore Majorana Ctr, Sci Culture, Italian Soc Electron Microscopy ID ENERGY-LOSS SPECTROSCOPY; DARK-FIELD STEM; GRAIN-BOUNDARIES; SCATTERED ELECTRONS; ATOMIC-STRUCTURE; THIN SPECIMENS; IMAGE-CONTRAST; ADF STEM; RESOLUTION; CRYSTALS C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Pennycook, SJ (reprint author), Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. NR 71 TC 87 Z9 88 U1 1 U2 11 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0168-132X BN 0-7923-5939-9 J9 NATO ADV SCI I E-APP PY 1999 VL 364 BP 161 EP 207 PG 47 WC Materials Science, Characterization & Testing; Microscopy; Spectroscopy SC Materials Science; Microscopy; Spectroscopy GA BP93X UT WOS:000086691200007 ER PT B AU Robinson, AL Baxter, LL Sclippa, G Junker, H Widell, KE Dayton, DC Belle-Oudry, D Freeman, M Walbert, G Goldberg, P AF Robinson, AL Baxter, LL Sclippa, G Junker, H Widell, KE Dayton, DC Belle-Oudry, D Freeman, M Walbert, G Goldberg, P BE Gupta, RP Wall, TF Baxter, L TI Fireside considerations when cofiring biomass with coal in PC boilers SO IMPACT OF MINERAL IMPURITIES IN SOLID FUEL COMBUSTION LA English DT Proceedings Paper CT Engineering Foundation Conference on Mineral Matter in Fuels CY NOV 02-07, 1997 CL KONA, HI SP Engn Fdn, Cooperative Res Ctr Black Coal Utilisat, Cooperative Res Ctr Power Generat Low Rank Coal, Ctr Coal Utilisat, Idemitsu Kosan Co Ltd, EBARA Corp, IHI Co Ltd, Kawasaki Heavy Ind, Elect Power Dev Co, Japan Cement Assoc ID COMBUSTION C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Robinson, AL (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46126-9 PY 1999 BP 247 EP 258 PG 12 WC Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical SC Energy & Fuels; Engineering GA BP33M UT WOS:000084731000018 ER PT B AU Robinson, AL Buckley, SG Sclippa, G Baxter, LL AF Robinson, AL Buckley, SG Sclippa, G Baxter, LL BE Gupta, RP Wall, TF Baxter, L TI In situ measurements of the thermal conductivity of ash deposits formed in a pilot-scale combustor SO IMPACT OF MINERAL IMPURITIES IN SOLID FUEL COMBUSTION LA English DT Proceedings Paper CT Engineering Foundation Conference on Mineral Matter in Fuels CY NOV 02-07, 1997 CL KONA, HI SP Engn Fdn, Cooperative Res Ctr Black Coal Utilisat, Cooperative Res Ctr Power Generat Low Rank Coal, Ctr Coal Utilisat, Idemitsu Kosan Co Ltd, EBARA Corp, IHI Co Ltd, Kawasaki Heavy Ind, Elect Power Dev Co, Japan Cement Assoc ID COAL C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Robinson, AL (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46126-9 PY 1999 BP 485 EP 496 PG 12 WC Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical SC Energy & Fuels; Engineering GA BP33M UT WOS:000084731000036 ER PT B AU Belle-Oudry, D Dayton, DC AF Belle-Oudry, D Dayton, DC BE Gupta, RP Wall, TF Baxter, L TI Bench-scale biomass/coal cofiring studies SO IMPACT OF MINERAL IMPURITIES IN SOLID FUEL COMBUSTION LA English DT Proceedings Paper CT Engineering Foundation Conference on Mineral Matter in Fuels CY NOV 02-07, 1997 CL KONA, HI SP Engn Fdn, Cooperative Res Ctr Black Coal Utilisat, Cooperative Res Ctr Power Generat Low Rank Coal, Ctr Coal Utilisat, Idemitsu Kosan Co Ltd, EBARA Corp, IHI Co Ltd, Kawasaki Heavy Ind, Elect Power Dev Co, Japan Cement Assoc C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Belle-Oudry, D (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46126-9 PY 1999 BP 569 EP 579 PG 11 WC Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical SC Energy & Fuels; Engineering GA BP33M UT WOS:000084731000042 ER PT B AU Lipka, G AF Lipka, G BE Singh, A Hinze, J Coble, RJ TI Owner involvement in construction at a national laboratory SO IMPLEMENTATION OF SAFETY AND HEALTH ON CONSTRUCTION SITES LA English DT Proceedings Paper CT 2nd International Conference of CIB Working Commission W99 CY MAR 24-27, 1999 CL HONOLULU, HI SP Carter & Burgess, Corp Headquarters, Natl Sci Fdn, HI Occupat Safety & Hlth Div, HI Dept Transportat, Univ Hawaii Manoa, Construct Educ Concepts AB In a construction project, the contractor and the owner each have a responsibility for ensuring the health and safety of personnel on a project site. The contractor has the responsibility for ensuring that the provisions of OSHA's safety and health regulations are followed and that the work is conducted in a safe and well thought out manner (Kohn 1996). The owner has a responsibility for disclosing to the contractor those owner-controlled hazards that are present in the work area due to ongoing and past operations (OSHA 1997). With the owner taking an active role in disclosing the potential hazards, the contractor is able to account for, plan, and mitigate potential health and safety issues during the performance phase of the project. At Sandia National Laboratories, this disclosure is made early in the project through the use of processes developed specifically for this purpose. C1 Sandia Natl Labs, Facil ES&H, Albuquerque, NM 87185 USA. RP Lipka, G (reprint author), Sandia Natl Labs, Facil ES&H, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU A A BALKEMA PUBLISHERS PI LEIDEN PA SCHIPHOLWEG 107C, PO BOX 447, 2316 XC LEIDEN, NETHERLANDS BN 90-5809-036-1 PY 1999 BP 403 EP 409 PG 7 WC Construction & Building Technology; Public, Environmental & Occupational Health SC Construction & Building Technology; Public, Environmental & Occupational Health GA BM63E UT WOS:000079308700055 ER PT S AU Hetherington, DL Stein, DJ Lauffer, JP Wyckoff, EE Shingledecker, DM AF Hetherington, DL Stein, DJ Lauffer, JP Wyckoff, EE Shingledecker, DM BE Amberiadis, K Kissinger, G Okumura, K Pabbisetty, S Weiland, LH TI Analysis of in-situ vibration monitoring for end-point detection of CMP planarization processes SO IN-LINE CHARACTERIZATION, YIELD RELIABILITY, AND FAILURE ANALYSES IN MICROELECTRONIC MANUFACTURING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on In-Line Characterization, Yield Reliability, and Failure Analyses in Microelectronic Manufacturing CY MAY 19-21, 1999 CL EDINBURGH, SCOTLAND SP European Opt Soc, Soc Photo Opt Instrumentat Engineers, Commiss European Communities, Directorate Gen Sci Res & Dev, Scottish Enterprise, Sira Technol Ctr, UK, Institut Elect Engineers, UK DE chemical mechanical polishing; CMP; planarization; endpoint; vibration AB This paper details the analysis of vibration monitoring for end-point control in oxide CMP processes. Two piezoelectric accelerometers were integrated onto the backside of a stainless steel polishing head of an IPEC 472 polisher. One sensor was placed perpendicular to the carrier plate (vertical) and the other parallel to the plate (horizontal). Wafers patterned with metal and coated with oxide material were polished at different speeds and pressures. Our results show that it is possible to sense a change in the vibration signal over time during planarization of oxide material on patterned wafers. The horizontal accelerometer showed more sensitivity to change in vibration amplitude compared to the vertical accelerometer for a given polish condition. At low carrier and platen rotation rates, the change in vibration signal over time at fixed frequencies decreased approximately 1/2 - 1 order of magnitude (ova the 2 to 10 psi polish pressure ranges). At high rotation speeds, the vibration signal remained essentially constant indicating that other factors dominated the vibration signal. These results show that while it is possible to sense changes in acceleration during polishing, more robust hardware and signal processing algorithms are required to ensure its use over a wide range of process conditions. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hetherington, DL (reprint author), Sandia Natl Labs, MS 1084, Albuquerque, NM 87185 USA. NR 13 TC 3 Z9 3 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3223-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3743 BP 89 EP 101 DI 10.1117/12.346902 PG 13 WC Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics SC Engineering; Materials Science; Optics GA BN20H UT WOS:000081061200010 ER PT S AU Stein, DJ Hetherington, DL AF Stein, DJ Hetherington, DL BE Amberiadis, K Kissinger, G Okumura, K Pabbisetty, S Weiland, LH TI Prediction of tungsten CMP pad life using blanket removal rate data and endpoint data obtained from process temperature and carrier motor current measurements SO IN-LINE CHARACTERIZATION, YIELD RELIABILITY, AND FAILURE ANALYSES IN MICROELECTRONIC MANUFACTURING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on In-Line Characterization, Yield Reliability, and Failure Analyses in Microelectronic Manufacturing CY MAY 19-21, 1999 CL EDINBURGH, SCOTLAND SP European Opt Soc, Soc Photo Opt Instrumentat Engineers, Commiss European Communities, Directorate Gen Sci Res & Dev, Scottish Enterprise, Sira Technol Ctr, UK, Institut Elect Engineers, UK AB Several techniques to predict pad failure during tungsten CMP were investigated for a specific consumable set. These techniques include blanket polish rate measurements and metrics derived from two endpoint detection schemes. Blanket polish rate decreased significantly near pad failure. Metrics from the thermal endpoint technique included change in peak temperature, change in the time to reach peak temperature, and the change in the slope of the temperature trace just prior to peak temperature all as a function of pad life. Average carrier motor current before endpoint was also investigated. Changes in these metrics were observed however these changes, excluding time to peak process temperature, were either not consistent between pads or too noisy to be reliable predictors of pad failure. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Stein, DJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 6 Z9 6 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3223-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3743 BP 112 EP 119 DI 10.1117/12.346904 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics SC Engineering; Materials Science; Optics GA BN20H UT WOS:000081061200012 ER PT S AU Hetherington, DL Stein, DJ AF Hetherington, DL Stein, DJ BE Ajuria, S Jakubczak, JF TI In-line monitoring of chemical-mechanical polishing processes SO IN-LINE METHODS AND MONITORS FOR PROCESS AND YIELD IMPROVEMENT SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on In-Line Methods and Monitors for Process and Yield Improvement CY SEP 22-23, 1999 CL SANTA CLARA, CA SP SPIE, Electrochem Soc, SolidState Technol, Amer Vacuum Soc, Reliability Engn Assoc Japan DE chemical mechanical polishing; CMP; planarization; endpoint; in-line monitoring; process control ID END-POINT DETECTION; CMP; PLANARIZATION; TECHNOLOGY AB We present an overview of in-line monitoring of chemical-mechanical polishing (CMP) processes. We discuss the technical challenges and review many of the approaches that have been published. Several methods rue currently under investigation including optical, thermal (pad temperature), friction (torque motor current), electrochemical, and acoustic (vibration). C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, MS 1084, Albuquerque, NM 87185 USA. EM dlhethe@sandia.gov NR 37 TC 4 Z9 4 U1 0 U2 5 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3481-7 J9 PROC SPIE PY 1999 VL 3884 BP 24 EP 35 DI 10.1117/12.361329 PG 12 WC Computer Science, Hardware & Architecture; Engineering, Chemical; Engineering, Manufacturing; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BN99V UT WOS:000083811300004 ER PT S AU Beaver, CL Gemmell, PS Johnston, AM Neumann, W AF Beaver, CL Gemmell, PS Johnston, AM Neumann, W BE Varadharajan, V Mu, Y TI On the cryptographic value of the q(th) root problem SO INFORMATION AND COMMUNICATON SECURITY, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 2nd International Conference on Information and Communication Security (ICICS 99) CY NOV 09-11, 1999 CL SYDNEY, AUSTRALIA SP Univ Western Sydney Nepean, Distributed Syst & Network Res Unit, IEEE Comp Chapter, NSW, Australian Comp Soc, Harvey World Travel ID ALGORITHM AB We show that, for a prime q and a group G, if ord(G) = q(k)r, k > 1, and r is smooth, then finding a q(th) root in G, is equivalent to the discrete logarithm problem over G (note that the discrete logarithm problem over the group G reduces to the discrete logarithm problem over a subgroup of order q - see reference [5]). Several publications describe techniques for computing qth roots (see [3] and [1]). All have the stated or implied requirement of computing discrete logarithm in a subgroup of order q. The emphasis here will be on demonstrating that with a fairly general q(th) root oracle, discrete logarithms in a subgroup of order q may be found, describing the cryptographic significance of this problem, and in introducing two new public key signature schemes based on it. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Albuquerque, NM 87108 USA. RP Beaver, CL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-66682-6 J9 LECT NOTES COMPUT SC PY 1999 VL 1726 BP 135 EP 142 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Theory & Methods SC Computer Science GA BQ39E UT WOS:000088228700010 ER PT S AU Lysne, P Lee, G Jones, L Roschke, M AF Lysne, P Lee, G Jones, L Roschke, M GP IEEE COMPUTER IEEE COMPUTER TI HPSS at Los Alamos: Experiences and analysis SO INFORMATION-BASED ACCESS TO STORAGE: THE FOUNDATION OF INFORMATION SYSTEMS, PROCEEDINGS SE IEEE SYMPOSIUM ON MASS STORAGE SYSTEMS - PROCEEDINGS LA English DT Proceedings Paper CT 16th IEEE Symposium on Mass Storage Systems in Cooperation with the 7th NASA Goddard Conference on Mass Storage Systems and Technologies CY MAR 15-18, 1999 CL SAN DIEGO, CA SP IEEE, Comp Soc, Inst Elect & Electr Engineets Inc, NASA, Goddard Space Flight Ctr AB The High Performance Storage System (HPSS) is currently deployed on the open and secure networks at Los Alamos National Laboratory (LANL). Users of the Accelerated Strategic Computing Initiative (ASCI) system with 6,144 processors and our similar Advanced Computing Laboratory (ACL) system, both from SGI/Cray, access HPSS for their data storage. We discuss our current HPSS configurations and how our users access HPSS. We analyze the performance between HPSS and these systems. We also discuss our projected storage and storage performance requirements for the next several years and what we are planning to meet those needs. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Lysne, P (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1051-9173 BN 0-7695-0204-0 J9 IEEE S MASS STOR SYS PY 1999 BP 150 EP 157 DI 10.1109/MASS.1999.830017 PG 8 WC Computer Science, Information Systems SC Computer Science GA BP90L UT WOS:000086558000014 ER PT S AU Hanushevsky, A Nowak, M AF Hanushevsky, A Nowak, M GP IEEE COMPUTER IEEE COMPUTER TI Pursuit of a scalable high performance multi-petabyte database SO INFORMATION-BASED ACCESS TO STORAGE: THE FOUNDATION OF INFORMATION SYSTEMS, PROCEEDINGS SE IEEE SYMPOSIUM ON MASS STORAGE SYSTEMS - PROCEEDINGS LA English DT Proceedings Paper CT 16th IEEE Symposium on Mass Storage Systems in Cooperation with the 7th NASA Goddard Conference on Mass Storage Systems and Technologies CY MAR 15-18, 1999 CL SAN DIEGO, CA SP IEEE, Comp Soc, Inst Elect & Electr Engineets Inc, NASA, Goddard Space Flight Ctr AB When the BaBar experiment at the Stanford Linear Accelerator Center starts in April 1999, it will generate approximately 200TB/year of data at a rate of 10MB/sec for 10 years. A mere six years later, CERN, the European Laboratory for Particle Physics, will start an experiment whose data storage requirements are two orders of magnitude larger. In both experiments, all of the data will reside in Objectivity databases accessible via the Advanced Multi-threaded Server (AMS). The quantity and rate at which the data is produced requires the use of a high performance hierarchical mass storage system in place of a standard Unix file system. Furthermore, the distributed nature of the experiment, involving scientists from 80 Institutions in 10 countries, also requires an extended security infrastructure not commonly found in standard Unix file systems. The combination of challenges that must be overcome in order to effectively deal with a multi-petabyte object oriented database is substantial. Our particular approach marries an optimized Unix file system with an industrial-strength Mass Storage System. This paper describes what we had to do to create a robust and uniform system based on these components. C1 Stanford Linear Accelerator Ctr, Menlo Park, CA 94025 USA. RP Hanushevsky, A (reprint author), Stanford Linear Accelerator Ctr, Menlo Park, CA 94025 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1051-9173 BN 0-7695-0204-0 J9 IEEE S MASS STOR SYS PY 1999 BP 169 EP 175 DI 10.1109/MASS.1999.830026 PG 7 WC Computer Science, Information Systems SC Computer Science GA BP90L UT WOS:000086558000016 ER PT S AU Whiteside, RA Friedman-Hill, EJ Detry, RJ AF Whiteside, RA Friedman-Hill, EJ Detry, RJ BE Mills, JJ Kimura, F TI PRE: A framework for enterprise integration. SO INFORMATION INFRASTRUCTURE SYSTEMS FOR MANUFACTURING II SE INTERNATIONAL FEDERATION FOR INFORMATION PROCESSING LA English DT Proceedings Paper CT 3rd International Working Conference on the Design of Information Infrastructure System for Manufacturing (DIISM 98) CY MAY 18-20, 1998 CL FT WORTH, TX SP Int Federat Informat Processing, TC5, WG5 3 5 7 DE CORBA; integration; framework AB Sandia National Laboratories' Product Realization Environment (PRE) is a lightweight, CORBA-based framework for the integration of a broad variety of applications. These applications are "wrapped" for use in the PRE framework as reusable components. For example, some of the PRE components currently available include: our product data management (PDM) system, our human resources database, several finite element analysis programs, and a variety of image and document format converters. PRE enables the development of end-user applications (as Java applets, for example) that use these components as building blocks. To aid such development, the PreLib library (available in both C++ and Java) permits both wrapping and using these components without knowledge of either CORBA or the security mechanisms used. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Whiteside, RA (reprint author), Sandia Natl Labs, MS 9012,POB 969, Livermore, CA 94551 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC PUBLISHERS PI NORWELL PA 101 PHILIP DRIVE, ASSINIPPI PARK, NORWELL, MA 02061 USA SN 1571-5736 BN 0-412-84450-8 J9 INT FED INFO PROC PY 1999 VL 16 BP 65 EP 78 PG 14 WC Automation & Control Systems; Computer Science, Software Engineering; Engineering, Manufacturing SC Automation & Control Systems; Computer Science; Engineering GA BP38F UT WOS:000084929000004 ER PT S AU Mosher, JC Leahy, RM Shattuck, DW Baillet, S AF Mosher, JC Leahy, RM Shattuck, DW Baillet, S BE Kuba, A Samal, M ToddPokropek, A TI MEG source imaging using multipolar expansions SO INFORMATION PROCESSING IN MEDICAL IMAGING, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 16th International Conference on Information Processing in Medical Imaging (IPMI 99) CY JUN 28-JUL 02, 1999 CL VISEGRAD, HUNGARY SP Jozsef Attila Univ, Inst Informat, Charles Univ, 1st Fac Med, Hungarian Natl Comm Technol Dev, Philips Med Syst Nederland BV, Czech Soc Nucl Med, Czech Med Assoc, Leapfrog Technol Ltd, London ID SOURCE LOCALIZATION; MUSIC; EEG AB We describe the use of truncated multipolar expansions for producing dynamic images of cortical neural activation from measurements of the magnetoencephalogram. We use a signal-subspace method to find the locations of a set of multipolar sources, each of which represents a region of activity in the cerebral cortex. Our method builds up an estimate of the sources in a recursive manner, i.e. we first search for point current dipoles, then magnetic dipoles, and finally first order multipoles. The dynamic behavior of these sources is then computed using a linear fit to the spatiotemporal data. The final step in the procedure is to map each of the multipolar sources into an equivalent distributed source on the cortical surface. The method is demonstrated through a Monte Carlo simulation. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ So Calif, Signal & Image Proc Inst, Los Angeles, CA 90089 USA. RP Mosher, JC (reprint author), Los Alamos Natl Lab, MS D454, Los Alamos, NM 87545 USA. RI Samal, Martin/I-7868-2016 NR 15 TC 4 Z9 4 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-66167-0 J9 LECT NOTES COMPUT SC PY 1999 VL 1613 BP 15 EP 28 PG 14 WC Computer Science, Theory & Methods; Radiology, Nuclear Medicine & Medical Imaging SC Computer Science; Radiology, Nuclear Medicine & Medical Imaging GA BS60G UT WOS:000170515200002 ER PT S AU Klein, GJ AF Klein, GJ BE Kuba, A Samal, M ToddPokropek, A TI Forward deformation of PET volumes using non-uniform elastic material constraints SO INFORMATION PROCESSING IN MEDICAL IMAGING, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 16th International Conference on Information Processing in Medical Imaging (IPMI 99) CY JUN 28-JUL 02, 1999 CL VISEGRAD, HUNGARY SP Jozsef Attila Univ, Inst Informat, Charles Univ, 1st Fac Med, Hungarian Natl Comm Technol Dev, Philips Med Syst Nederland BV, Czech Soc Nucl Med, Czech Med Assoc, Leapfrog Technol Ltd, London ID FIELDS; IMAGES AB A method for non-rigidly deforming 3D PET datasets is described. The method uses a Lagrangian motion field description and a forward deformation mapping. To regularize the deformation, an anisotropic strain energy function is used that separately models the material properties of cardiac and background tissues. The method is applied to motion compensation in PET so that different time frames of a cardiac sequence may be combined. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Klein, GJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Samal, Martin/I-7868-2016 NR 8 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-66167-0 J9 LECT NOTES COMPUT SC PY 1999 VL 1613 BP 358 EP 363 PG 6 WC Computer Science, Theory & Methods; Radiology, Nuclear Medicine & Medical Imaging SC Computer Science; Radiology, Nuclear Medicine & Medical Imaging GA BS60G UT WOS:000170515200029 ER PT S AU Weber, PG Borel, CC Clodius, WB Cooke, BJ Smith, BW AF Weber, PG Borel, CC Clodius, WB Cooke, BJ Smith, BW BE Holst, GC TI Design considerations, modeling and analysis for the Multispectral Thermal Imager. SO INFRARED IMAGING SYSTEMS: DESIGN, ANALYSIS, MODELING, AND TESTING X SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Infrared Imaging Systems - Design, Analysis, Modeling, and Testing X CY APR 07-08, 1999 CL ORLANDO, FL SP SPIE DE modeling; analysis; system design; multispectral imaging; thermal imaging; calibration ID CALIBRATION AB The design of remote sensing systems is driven by the need to provide cost-effective, substantive answers to questions posed by our customers. This is especially important for space-based systems, which tend to be expensive, and-which generally cannot be changed after they are launched. We report here on the approach we employed in developing the desired attributes of a satellite mission, namely the Multispectral Thermal Imager. After an initial scoping study, we applied a procedure which we call: "End-to-end modeling and analysis (EEM)." We began with target attributes, translated to observable signatures and then propagated the signatures through the atmosphere to the sensor location. We modeled the sensor attributes to yield a simulated data stream, which was then analyzed to retrieve information about the original target. The retrieved signature was then compared to the original to obtain a figure of merit: hence the term "end-to-end modeling and analysis." We base the EEM in physics to ensure high fidelity and to permit scaling. As the actual design of the payload evolves, and as real hardware is tested, we can update the EEM to facilitate trade studies, and to judge, for example, whether components that deviate from specifications are acceptable. C1 Univ Calif Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, Los Alamos, NM 87545 USA. RP Weber, PG (reprint author), Univ Calif Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, D436, Los Alamos, NM 87545 USA. NR 32 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3175-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3701 BP 144 EP 154 DI 10.1117/12.352968 PG 11 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN40K UT WOS:000081824900012 ER PT S AU Cooke, BJ Smith, BW Laubscher, BE Villeneuve, PV Briles, S AF Cooke, BJ Smith, BW Laubscher, BE Villeneuve, PV Briles, S BE Holst, GC TI Analysis and system design framework for infrared spatial heterodyne spectrometers SO INFRARED IMAGING SYSTEMS: DESIGN, ANALYSIS, MODELING, AND TESTING X SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Infrared Imaging Systems - Design, Analysis, Modeling, and Testing X CY APR 07-08, 1999 CL ORLANDO, FL SP SPIE DE infrared Fourier Transform Spectroscopy; spatially modulated FTS ID NOISE AB We present a preliminary analysis and design framework developed for the evaluation and optimization of infrared, Imaging Spatial Heterodyne Spectrometer (SHS) electro-optic systems. Commensurate with conventional interferometric spectrometers, SHS modeling requires an integrated analysis environment for rigorous evaluation of system error propagation due to detection process, detection noise, system motion, retrieval algorithm and calibration algorithm. The analysis tools provide for optimization of critical system parameters and components including: i) optical aperture, f-number, and spectral transmission, ii) SHS interferometer grating and Littrow parameters, and iii) image plane requirements as well as cold shield, optical filtering, and focal-plane dimensions, pixel dimensions and quantum efficiency, iv) SHS spatial and temporal sampling parameters, and v) retrieval and calibration algorithm issues. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cooke, BJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS-D448, Los Alamos, NM 87545 USA. NR 26 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3175-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3701 BP 167 EP 191 DI 10.1117/12.352971 PG 25 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN40K UT WOS:000081824900014 ER PT S AU Laubscher, BE Smith, BW Cooke, BJ La Delfe, PC Berggren, RR Villeneuve, PV Goeller, RM Obbink, GM Milligan, S Howard, JW Norton, PR Stegall, M Burgett, CB Harlander, JM Horton, RF AF Laubscher, BE Smith, BW Cooke, BJ La Delfe, PC Berggren, RR Villeneuve, PV Goeller, RM Obbink, GM Milligan, S Howard, JW Norton, PR Stegall, M Burgett, CB Harlander, JM Horton, RF BE Holst, GC TI The Infrared Imaging Spatial Heterodyne Spectrometer (IRISHS) experiment effort SO INFRARED IMAGING SYSTEMS: DESIGN, ANALYSIS, MODELING, AND TESTING X SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Infrared Imaging Systems - Design, Analysis, Modeling, and Testing X CY APR 07-08, 1999 CL ORLANDO, FL SP SPIE DE infrared spectroscopy; hyperspectral instruments; Fourier transform spectroscopy AB We present the Infrared Imaging Spatial Heterodyne Spectrometer (IRISHS) experiment. IRISHS is a new hyperspectral imaging spectrometer for remote sensing being developed by Los Alamos National Laboratory for use in identifying and assaying gases in the atmosphere when viewed against the Earth's background. The prototype instrument, which can operate between 8 and 1i.5 micrometers (although the current IR camera operates from 8 9.5 micrometers), will be described. Imaging spatial heterodyne spectrometer technology is discussed in four companion papers also presented at this symposium. IRISHS experiments began with a non-imaging "brassboard" instrument that allowed interferometer behavior to be investigated using a tunable CO, laser and an uncooled thermal 1R camera. Experience gained from the brassboard defined the imaging camera requirements for the prototype instrument. This imaging prototype, designed with refractive optics by Telic Optics, Inc., used a cooled HgCdTe 256x256 pixel focal plane array. Laboratory experiments investigating the operation of the instrument are discussed. Raw interferograms and the resulting spectral data are presented, illustrating the theory of operation as well as the performance of the prototype system. Future experiments will be outlined as well. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Laubscher, BE (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 5 TC 2 Z9 2 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3175-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3701 BP 194 EP 205 DI 10.1117/12.352970 PG 12 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN40K UT WOS:000081824900015 ER PT S AU Datskos, PG Rajic, S Egert, CM Datskou, I AF Datskos, PG Rajic, S Egert, CM Datskou, I BE Andresen, BF Scholl, MS TI Detection of infrared photons using the electronic stress in metal-semiconductor interfaces SO INFRARED TECHNOLOGY AND APPLICATIONS XXV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Infrared Technology and Applications XXV Conference CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE MEMS; micromechanical; photon detector; thermal detector; microcantilever; photo-induced stress; photo-emission ID MICROCANTILEVERS; RESOLUTION; SILICON; MICROSCOPY; SENSORS AB It is well known that the work function of metals decreases when they are placed in a nonpolar liquid A similar decrease occurs when the metal is placed into contact with a semiconductor forming a Schottky barrier. We report on a new method for detecting photons using the stress caused by photo-electrons emitted from a metal film surface in contact with a semiconductor microstructure. The photoelectrons diffuse into the microstructure and produce an electronic stress. The photon detection results from the measurement of the photo-induced bending of the microstructure. Internal photo-emission has been used in the past to detect photons, however, in those cases the detection was accomplished by measuring the current due to photoelectrons and not due to electronic stress. Small changes in position (displacement) of microstructures are routinely measured in atomic force microscopy (AFM) where atomic imaging of surfaces relies on the measurement of small changes (< 10(-9) m) in the bending of microcantilevers. m the present work we studied the photon response of Si microcantilevers with a thin film of Pt. The Si microcantilevers were 500 nm thick and had a 30 nm layer of Pt. Photons with high enough energies produce electrons from the platinum-silicon interface which diffuse into the Si and produce an electronic stress. Since the excess charge carriers cause the Si microcantilever to contract in length but not the Pt layer, the bimaterial microcantilever bends. In our present studies we used the optical detection technique to measure the photometric response of Pt-Si microcantilevers as a function of photon energy. The charge carriers responsible for the photo-induced stress in Si, were produced via internal photo-emission using a diode laser with wavelength lambda =1550 nm. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Datskos, PG (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 29 TC 5 Z9 5 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3172-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3698 BP 151 EP 160 DI 10.1117/12.354516 PG 10 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN59F UT WOS:000082322000018 ER PT S AU Smith, BW Laubscher, B Cooke, B LaDelfe, P Harlander, J Howard, JW Milligan, S AF Smith, BW Laubscher, B Cooke, B LaDelfe, P Harlander, J Howard, JW Milligan, S BE Andresen, BF Scholl, MS TI IRISHS, the Infrared Imaging Spatial Heterodyne Spectrometer: a new pushbroom Fourier transform ultraspectral imager with no moving parts SO INFRARED TECHNOLOGY AND APPLICATIONS XXV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Infrared Technology and Applications XXV Conference CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE imaging spectroscopy; infrared spectroscopy; Fourier transform spectroscopy; remote sensing ID SPECTROSCOPY AB Imaging spatial heterodyne spectroscopy (ISHS) was invented by Roesler and Harlander and applied to the far ultraviolet. It also has advantages for remote sensing applications in the visible and infrared bands. We have designed, assembled, and ground-tested a new instrument designed for eventual airborne or spaceborne deployment for imaging spectroscopy at ultraspectral resolution (1 cm(-1)). IRISHS is a true, imaging, Fourier transform spectrometer (FTS) with a fully open square field of view (no slit), where the third dimension required to assemble data cubes is acquired by scanning the FOV linearly over the scene. Spatially displayed fringes are differenced ("heterodyned") with a spatial frequency determined by a pair of diffraction gratings, giving easily sampled fringe patterns. The current system operates between 8 and 12.5 microns in six sub-bands and employs a 256x256 pixel focal plane array. In comparison to dispersive imaging spectrometers with equivalent resolution, ISHS has: 1) much larger etendue in a small package; 2) full-field imaging for ease in image reconstruction; 3) approximately the same signal-to-noise ratio (S/N) in equivalent observing scenarios, except in the case where the entire dispersive spectrometer is cryogenically cooled. In comparison to conventional FTS, ISHS has: I) no moving parts during data collection; 2) pushbroom imaging, 3) approximately the same SM for equivalent conditions, 4) much lower data rate. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Smith, BW (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 21 TC 4 Z9 4 U1 0 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3172-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3698 BP 501 EP 509 DI 10.1117/12.354552 PG 9 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN59F UT WOS:000082322000054 ER PT S AU Smith, BW Harlander, JM AF Smith, BW Harlander, JM BE Andresen, BF Scholl, MS TI Imaging spatial heterodyne spectroscopy: theory and practice SO INFRARED TECHNOLOGY AND APPLICATIONS XXV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Infrared Technology and Applications XXV Conference CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE imaging spectroscopy; infrared spectroscopy; Fourier transform spectroscopy AB Spatial heterodyne spectroscopy (SHS) is a Fourier transform spectroscopy technique capable of very high spectral resolution with no moving parts. The original work described non-imaging SHS, and it became a true imaging spectroscopy technique without much fanfare. We describe the imaging technique and relate it to another "image plane interferometer" described by Horton, called HEIFTS, which does not have heterodyned fringes. One configuration of a basic SHS is a two-beam Michelson interferometer with both mirrors replaced by diffraction gratings operated in the Littrow configuration. To convert a parallel light SHS device to imaging, incoming light must be focussed on the gratings, so that each grating receives a full image of the scene. To acquire three-dimensional data cubes, the open (no slit) field of view is scanned across the scene. Although the focal plane array sees both spatial and spectral information, they are not mixed, because information is encoded by optical path difference according to position on the focal plane. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Smith, BW (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. NR 4 TC 8 Z9 8 U1 1 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3172-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3698 BP 925 EP 931 DI 10.1117/12.354497 PG 7 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN59F UT WOS:000082322000097 ER PT B AU Lubeck, O Hoisie, A Bassetti, F Cameron, K Luo, Y Wasserman, H AF Lubeck, O Hoisie, A Bassetti, F Cameron, K Luo, Y Wasserman, H BE Veidenbaum, A Joe, K TI ASCI application performance and the impact of commodity processor architectural trends SO INNOVATIVE ARCHITECTURE FOR FUTURE GENERATION HIGH-PERFORMANCE PROCESSORS AND SYSTEMS LA English DT Proceedings Paper CT International Workshop on Innovative Architecture for Future Generation High-Performance Processors and Systems CY 1998 CL MAUI, HI SP Maui High Performance Comp Ctr ID COMPUTER AB The purpose of this paper is to summarize recent performance results from an important ASCI-related application and to speculate on how trends within the computer industry and in computer architecture relate to these results. C1 Los Alamos Natl Lab, Sci Comp Grp, Los Alamos, NM 87544 USA. RP Los Alamos Natl Lab, Sci Comp Grp, Los Alamos, NM 87544 USA. NR 32 TC 0 Z9 0 U1 1 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0125-7 PY 1999 BP 3 EP 6 DI 10.1109/IWIA.1998.779067 PG 4 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA BN58H UT WOS:000082307700001 ER PT S AU Okumus, SC Unal, O Kramer, MJ Akinc, M AF Okumus, SC Unal, O Kramer, MJ Akinc, M BE Bansal, NP Singh, JP TI Mechanical properties of plasma-sprayed Mo5Si3-MoB-MoSi2 system SO INNOVATIVE PROCESSING AND SYNTHESIS OF CERAMICS, GLASSES, AND COMPOSITES II SE CERAMIC TRANSACTIONS LA English DT Proceedings Paper CT 100th Annual Meeting of the American-Ceramic-Society CY MAY 03-06, 1998 CL CINCINNATI, OH SP Amer Ceram Soc ID COMPOSITES AB Mechanical properties of plasma-sprayed Mo5Si3-MoB-MoSi2 specimens were studied between room temperature and 1200 degrees C. The comparison of hardness, strength and fracture toughness results from perpendicular and parallel as-deposited specimens, showed that the local anisotropy has little effect on macroscopic properties. However, temperature had a major impact on the deformation and fracture behavior. The specimens exhibited nonlinear behavior at 800 degrees C and the strength increased up to 1000 degrees C, and the crack growth at elevated temperatures was unusually stable. The presence of a significant amount of amorphous phase(s) at the splat boundaries appeared to be the main reason for temperature dependent observations. C1 Iowa State Univ, Ames Lab, Ames, IA 50010 USA. RP Okumus, SC (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50010 USA. NR 5 TC 3 Z9 3 U1 1 U2 1 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 1042-1122 BN 1-57498-060-2 J9 CERAM TRANS PY 1999 VL 94 BP 347 EP 360 PG 14 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BN02S UT WOS:000080430700032 ER PT B AU Smallwood, DO AF Smallwood, DO GP INST ENVIRONM SCI & TECHNOL INST ENVIRONM SCI & TECHNOL TI Multiple shaker random vibration control - An update SO INSTITUTE OF ENVIRONMENTAL SCIENCES AND TECHNOLOGY, PROCEEDINGS 1999: CONTAMINATION CONTROL - DESIGN, TEST, AND EVALUATION - PRODUCT RELIABILITY LA English DT Proceedings Paper CT 45th Annual Technical Meeting and Exposition of the IEST on Todays Training for Tomorrows World CY MAY 02-07, 1999 CL ONTARIO, CA SP Inst Environm Sci & Technol DE multiple shaker control; multiple axis vibration testing; vibration; testing; random; sine; waveform control; transient vibration AB The theory of the control of multiple shakers driving a single test item is reviewed. Several improvements that have been introduced since the original papers on the subject will be discussed. The improvements include: 1) specification of the control spectra; 2) the control of non-square systems (the number of shakers does not have to be equal to the number of control points); 3) the connection between sine testing, waveform control, and random control, 4) improvements in feedback control; 5) overlap-add versus time domain randomization; and 6) reproduction of non-Gaussian waveforms. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Smallwood, DO (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 17 TC 0 Z9 0 U1 1 U2 1 PU INST ENVIRONMENTAL SCIENCES PI MT PROSPECT PA 940 E NORTHWEST HIGHWAY, MT PROSPECT, IL 60056 USA BN 1-877862-66-5 PY 1999 BP 212 EP 221 PG 10 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BN81R UT WOS:000083082600029 ER PT J AU Volkan, M Lee, Y Vo-Dinh, T AF Volkan, M Lee, Y Vo-Dinh, T TI AOTF-based remote sensor with sol-gel probe SO INSTRUMENTATION SCIENCE & TECHNOLOGY LA English DT Article ID ACOUSTOOPTIC TUNABLE FILTER; OPTICAL CHEMICAL SENSORS; PH SENSOR; FLUORESCENCE; SYSTEM; DYE; SPECTROMETRY; BIOSENSORS; GLASS AB We report the development and application of a sensor using acousto-optic tunable filter (AOTF) and sol-gel probe technology. A. pH-sensitive probe is used as a model sensing system with dextran derivatives of pH sensitive dyes doped into sol-gel thin films. We used a unique combination of pH-sensitive and pH-insensitive dual-label dye system. For optimization studies, the performance of these films as a pH sensing probe was evaluated using synchronous fluorescence detection. The performance of the a prototype AOTF-based monitor using a low-power argon laser as an ion excitation source was evaluated. C1 Oak Ridge Natl Lab, Div Life Sci, Adv Monitoring Dev Grp, Oak Ridge, TN 37831 USA. RP Vo-Dinh, T (reprint author), Oak Ridge Natl Lab, Div Life Sci, Adv Monitoring Dev Grp, POB 2008, Oak Ridge, TN 37831 USA. NR 28 TC 0 Z9 0 U1 0 U2 1 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 1073-9149 J9 INSTRUM SCI TECHNOL JI Instrum. Sci. Technol. PY 1999 VL 27 IS 5 BP 343 EP 355 DI 10.1080/10739149908085871 PG 13 WC Chemistry, Analytical; Instruments & Instrumentation SC Chemistry; Instruments & Instrumentation GA 246JY UT WOS:000083161700002 ER PT J AU Auciello, O Krauss, AR Im, J Dhote, A Gruen, DM Aggarwal, S Ramesh, R Irene, EA Gao, Y Mueller, AH AF Auciello, O Krauss, AR Im, J Dhote, A Gruen, DM Aggarwal, S Ramesh, R Irene, EA Gao, Y Mueller, AH TI Studies of ferroelectric heterostructure thin films, interfaces, and device-related processes via in situ analytical techniques SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, CO DE in situ characterization; ferroelectric films; ion scattering; recoil spectroscopy; spectroscopic ellipsometry; SFM piezoresponse; X-ray scattering ID DIRECT RECOIL SPECTROSCOPY; ION-BEAM ANALYSIS; TIME-OF-FLIGHT; IN-SITU; FORCE MICROSCOPY; GROWTH-PROCESSES; SURFACE-STRUCTURE; REAL-TIME; SCATTERING; DEPOSITION AB The science and technology of ferroelectric thin films has experienced an explosive development during the last ten years. Low-density non-volatile ferroelectric random access memories (NVFRAMs) are now incorporated in commercial products such as "smart cards", while high permittivity capacitors are incorporated in cellular phones. However, substantial work is still needed to develop materials integration strategies for high-density memories. We have demonstrated that the implementation of complementary in situ characterization techniques is critical to understand film growth and device processes relevant to device development. We are using uniquely integrated time of flight ion scattering and recoil spectroscopy (TOF-ISARS) and spectroscopic ellipsometry (SE) techniques to perform in situ, real-time studies of film growth processes in the high background gas pressure required to growth ferroelectric thin films. TOF-ISARS provides information on surface processes, while SE permits the investigation of buried interfaces as they are being formed. Recent studies on SrBi(2)Ta(2)O(9) (SBT) and Ba(x)Sr(1-x)TiO(3) (BST) film growth and interface processes are discussed. Direct imaging of ferroelectric domains under applied electric fields can provide valuable information to understand domain dynamics in ferroelectric films. We discuss results of piezoresponse scanning force microscopy (SFM) imaging for nanoscale studies of polarization reversal and retention loss in Pb(Zr(x)Ti(1-x))O(3) (PZT)-based capacitors. Another powerful technique suitable for in situ, real-time characterization of film growth processes and ferroelectric film-based device operation is based on synchrotron X-ray scattering, which is currently being implemented at Argonne National Laboratory. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Univ Maryland, College Pk, MD 20742 USA. Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA. RP Auciello, O (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 39 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 27 IS 1-4 BP 1147 EP 1162 PG 16 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290RU UT WOS:000085692300012 ER PT J AU Gopalan, V Itagi, A Gerstl, S Swart, P Jia, QX Mitchell, TE Schlesinger, TE Stancil, DD AF Gopalan, V Itagi, A Gerstl, S Swart, P Jia, QX Mitchell, TE Schlesinger, TE Stancil, DD TI Ferroelectric domain kinetics in congruent LiTaO3 SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE electro-optic imaging microscopy; LiTaO3; ferroelectrics; domains; real-time kinetics AB We present real-time studies of nucleation and growth of 180 degrees ferroelectric domains in congruent LiTaO3 under an external electric field using optical microscopy. The measured wall velocities are an order of magnitude higher than those reported before using ex-situ techniques. Merger of growing domains form serrated fronts which show a further order of magnitude increase in wall velocity. A time dependent velocity is required in the Avrami theory to explain the change in domain area versus time at a constant electric field. We believe that these features of domain switching must be considered when studying ferroelectrics in general. C1 Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA. Carnegie Mellon Univ, Dept Elect & Comp Engn, Pittsburgh, PA 15213 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Gopalan, V (reprint author), Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. RI Stancil, Daniel/D-1339-2013; Jia, Q. X./C-5194-2008 OI Stancil, Daniel/0000-0002-2010-1381; NR 12 TC 0 Z9 0 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 27 IS 1-4 BP 1181 EP 1190 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290RU UT WOS:000085692300015 ER PT J AU Krauss, AR Dhote, A Auciello, O Im, J Ramesh, R Aggarwal, S AF Krauss, AR Dhote, A Auciello, O Im, J Ramesh, R Aggarwal, S TI Studies of hydrogen-induced degradation processes in Pb(Zr1-xTix)O-3 (PZT) and SrBi2Ta2O9 (SBT) ferroelectric film-based capacitors SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE BST; PZT; hydrogen annealing; ferroelectric; thin film; surface analysis; ion scattering; pulsed ion beam surface characterization ID ELECTRODE AB The integration of PZT and SBT film-based capacitors with Si integrated circuit technology requires the use of processing steps that may degrade the performance of individual device components. Hydrogen annealing to remove damage in the Si FET adversely affects both PZT and SBT, although the mechanisms of degradation are different. We have used Mass spectroscopy of recoiled ions (MSRI), X-ray diffraction (XRD), Raman spectroscopy and electrical characterization to study the mechanisms of hydrogen-induced degradation in these two materials. The mechanism responsible for degradation in SBT during hydrogen annealing appears to be hydrogen-induced volatilization of Bi from the near-surface region during film growth. Although there is a similar, but smaller, loss of Pb in PZT, the resulting change in stoichiometry is not responsible for the degradation of the ferroelectric properties. Raman spectroscopy reveals that PZT films exposed to hydrogen exhibit evidence for the formation of polar hydroxyl [OH-] bonds, which can block the movement of ions in the lattice and inhibit polarization. The possible sites for the incorporation of hydrogen are discussed in terms of ionic radii, and crystal structure. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Univ Maryland, Dept Mat Sci & Nucl Engn, College Pk, MD 20742 USA. RP Krauss, AR (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 8 TC 1 Z9 1 U1 1 U2 3 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 27 IS 1-4 BP 1191 EP 1201 PG 11 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290RU UT WOS:000085692300016 ER PT J AU Lu, P He, S Li, FX Jia, QX AF Lu, P He, S Li, FX Jia, QX TI Epitaxial growth and structural properties of conductive RuO2 thin films SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE conductive RuO2; epitaxial growth; structural properties; MOCVD ID CHEMICAL-VAPOR-DEPOSITION; SPUTTERED RUTHENIUM DIOXIDE; METALLIC OXIDE; CAPACITORS; ELECTRODES; SURFACE; SI AB Metal-organic chemical vapor deposition (MOCVD) has been used to deposit conductive oxide RuO2 thin films at different temperatures on (100) MgO and (100) LaAlO3 substrates. The microstructural properties of the RuO2 films have been studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution electron microscopy (HREM). Different growth and microstructural properties were observed for the films deposited on the two substrates. For example, the films on MgO are epitaxial at deposition temperatures as low as 350 degrees C, and the films on LaAlO3 are epitaxial only at deposition temperatures of 600 degrees C and above. The epitaxial films on MgO consist of two variants with an orientation relationship given by (110) RuO2//(100) MgO and [001] RuO2//[011]MgO. The epitaxial films on LaAlO3, on the other hand, contain four variants with an orientation relationship given by (200)RuO2//(100)LaAlO3 and [011] RuO2//[011] LaAlO3. The difference in growth and microstructural properties were explained based on geometrical considerations for the film and substrates. The RuO2/substrate interfaces and the RuO2 domain boundaries were also investigated by TEM and HREM. C1 New Mexico Inst Min & Technol, Dept Mat Sci & Engn, Socorro, NM 87801 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Lu, P (reprint author), New Mexico Inst Min & Technol, Dept Mat Sci & Engn, Socorro, NM 87801 USA. RI Jia, Q. X./C-5194-2008 NR 22 TC 0 Z9 0 U1 2 U2 4 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 26 IS 1-4 BP 839 EP 853 PG 15 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290RT UT WOS:000085692200016 ER PT J AU Kim, SH Kim, DJ Im, J Streiffer, SK Auciello, O Maria, JP Kingon, AI AF Kim, SH Kim, DJ Im, J Streiffer, SK Auciello, O Maria, JP Kingon, AI TI Impact of changes in the Pt heterostructure bottom electrodes on the ferroelectric properties of SBT thin films SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE ferroelectricity; SBT; chemical solution deposition; surface roughness; Pt heterostructure; film/electrode interface ID CAPACITORS; PT/TI AB The crystallinity and the microstructure of Sr0.8Bi2.3Ta2O9 (SBT) thin films improved with increasing annealing temperature, and strongly influenced the ferroelectric properties. In addition, the properties of SBT films, such as remanent polarization and leakage current density, are closely related to the film/electrode interface and surface roughness of the underlying electrode. SBT firms on Pt/TiO2/SiO2/Si and Pt/ZrO2/SiO2/Si substrates exhibited high remanent polarization, low leakage current density, and low voltage saturation as compared to SBT films on Pt/Ti/SiO2/Si substrates. This is deduced to be related to differences in film orientation, electrode roughness, and out-diffusion of Ti onto the surface of the bottom electrode. C1 N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Kim, SH (reprint author), N Carolina State Univ, Dept Mat Sci & Engn, Box 7907, Raleigh, NC 27695 USA. RI KIM, DONG-JOO/C-2277-2008; Streiffer, Stephen/A-1756-2009 NR 17 TC 0 Z9 0 U1 0 U2 1 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 26 IS 1-4 BP 955 EP 970 PG 16 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290RT UT WOS:000085692200024 ER PT J AU Gopalan, V Gahagan, KT Kawas, M Jia, QX Robinson, JM Mitchell, TE Schlesinger, TE Stancil, DD AF Gopalan, V Gahagan, KT Kawas, M Jia, QX Robinson, JM Mitchell, TE Schlesinger, TE Stancil, DD TI Integration of electro-optic lenses and scanners on ferroelectric LiTaO3 SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE integrated optics; feroelectrics; electro-optics; scanners; lenses ID DOMAIN INVERSION; CRYSTALS; LINBO3 AB An integrated electro-optic lens/scanner device was fabricated on ferroelectric LiTaO3 wafer. This was done using lithographically defined domain-inverted regions extending through the crystal thickness. A lens power of 0.233 cm(-1)kV(-1) and a scanner deflection of 12.68 mrad(-1) kV(-1) was observed. We also demonstrate an electro-optic lens stack collimator which collimates an input beam focused to 5 mu m waist diameter at 2.3kV. C1 Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Carnegie Mellon Univ, Dept Elect & Comp Engn, Pittsburgh, PA 15213 USA. RP Gopalan, V (reprint author), Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. RI Stancil, Daniel/D-1339-2013; Jia, Q. X./C-5194-2008 OI Stancil, Daniel/0000-0002-2010-1381; NR 7 TC 3 Z9 3 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 25 IS 1-4 BP 371 EP 376 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290RR UT WOS:000085692100005 ER PT J AU Gim, Y Gahagan, KT Kwon, C Hawley, M Gopalan, V Robinson, JM Mitchell, TE Jia, QX AF Gim, Y Gahagan, KT Kwon, C Hawley, M Gopalan, V Robinson, JM Mitchell, TE Jia, QX TI Growth of LiNbO3 films on single crystal sapphire substrates using pulsed laser deposition SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE LiNbO3; thin film; pulsed laser deposition; dielectric constant ID ACOUSTIC-WAVE PROPERTIES; NIOBATE THIN-FILMS; LITHIUM-NIOBATE; EPITAXIAL-GROWTH; 2ND-HARMONIC GENERATION AB We report on the epitaxial growth of LiNbO3 (11(2) over bar 0) films on sapphire (11(2) over bar 0) substrates using pulsed laser deposition. We have used a Li-enriched target of Li2NbO3 to compensate for the loss of Li at high deposition temperatures of 600-800 degrees C, X-ray theta-2 theta scans reveal that the crystal orientation of our LiNbO3 films is very sensitive to the deposition temperature and oxygen pressure. To obtain a single (11(2) over bar 0) orientation, we need to use a deposition temperature of 800 degrees C and an oxygen pressure of 10(-5) Torr. Otherwise, an extra (0001) orientation of LiNbO3 always occurs. From a rocking curve of the (11(2) over bar 0) peak, we have measured a full width at half maximum of 0.3 degrees, implying that our LiNbO3 (11(2) over bar 0) film is highly oriented. The measured dielectric constants of the LiNbO3 (0001) and (11(2) over bar 0) films at 1 MHz are 80 and 70, respectively. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Gim, Y (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS K763, Los Alamos, NM 87545 USA. RI Jia, Q. X./C-5194-2008 NR 20 TC 0 Z9 0 U1 0 U2 4 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 25 IS 1-4 BP 431 EP 442 PG 12 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290RR UT WOS:000085692100011 ER PT J AU Schloss, LF Haller, EE AF Schloss, LF Haller, EE TI The effect of growth temperature on pulsed laser deposited (Ba,Sr)TiO3 thin films designed for pyroelectric far-infrared detector applications SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE pyroelectric; (Ba;Sr)TiO3; pulsed laser deposition; deposition temperature; grain size; Curie temperature ID STRESS AB Pulsed laser deposited (Ba,Sr)TiO3 (BST) thin ferroelectric films, developed for use in pyroelectric detectors, have been grown on single crystal SrTiO3 substrates at temperatures ranging from 580 to 780 degrees C. Temperature-dependent capacitance-voltage measurements reveal Curie temperature shifts of more than 50 K. However the Curie temperature does not shift monotonically with growth temperature. With increasing deposition temperature, the BST films transform from amorphous to epitaxial. Within the epitaxial growth regime, an increase in deposition temperature results in an increase in crystalline column size. These structural changes alter both the type and magnitude of film stress, resulting in shifts in Curie temperature anal consequently, the optimal pyroelectric detector operating temperature. C1 Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Schloss, LF (reprint author), Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. NR 10 TC 0 Z9 4 U1 0 U2 1 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 25 IS 1-4 BP 443 EP 452 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290RR UT WOS:000085692100012 ER PT J AU Godfrey, RP Friessnegg, T Ramesh, R Tipton, CW Hoffman, RC Robertson, DN Poindexter, EH Quuada, MA Nielsen, B Keeble, DJ AF Godfrey, RP Friessnegg, T Ramesh, R Tipton, CW Hoffman, RC Robertson, DN Poindexter, EH Quuada, MA Nielsen, B Keeble, DJ TI Infrared absorbing oxide electrodes in epitaxial pyroelectric Pb-La-Ti-O heterostructures with controlled domain orientation SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE PLT; LSCO; oxide; infrared; pyroelectric; positron; epitaxial; domain orientation ID POSITRON-ANNIHILATION; VACANCY DEFECTS; THIN; MICROSTRUCTURE AB Oxide-based pyroelectric heterostructures of La-Sr-Co-O/Pb0.9La0.1Ti0.975O3/La-Sr-Co-O have been grown. Single-crystal LaAlO3 substrates were chosen to obtain high quality epitaxial thin films in order to address basic pyroelectric properties. The use of perovskite conducting oxide electrodes promotes the formation of phase pure pervoskite pyroelectric material. Additionally, these oxides exhibit strong infrared absorption, alpha = 10(5)/cm. An infrared absorbing electrode is beneficial for producing a simplified detector design-with enhanced detectivity. Variation of the deposition temperature produced control of the domain orientation. Pyroelectric measurements using the Byer-Roundy method have yielded pyroelectric: coefficients of 50 nC/cm(2)K. Both pyroelectric coefficients and pulsed polarization values show a clear dependence on the c-axis volume fraction. C1 Univ Maryland, Dept Phys, College Pk, MD 20742 USA. USA, Res Lab, Adelphi, MD 20783 USA. Genesis Engn Co, Lanham, MD USA. Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. Univ Dundee, Carnegie Lab Phys, Dundee DD1 4HN, Scotland. RP Godfrey, RP (reprint author), Univ Maryland, Dept Phys, College Pk, MD 20742 USA. RI Nielsen, Bent/B-7353-2009; Keeble, David /C-6633-2012 OI Nielsen, Bent/0000-0001-7016-0040; Keeble, David /0000-0002-5378-799X NR 11 TC 0 Z9 0 U1 1 U2 4 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 25 IS 1-4 BP 475 EP 487 PG 13 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290RR UT WOS:000085692100015 ER PT J AU Jia, QX Kwon, C Lu, P AF Jia, QX Kwon, C Lu, P TI Structural properties of Ba0.6Sr0.4TiO3 thin films on epitaxial RuO2 electrodes SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE RuO2; Ba0.6Sr0.4TiO3; thin film deposition ID PULSED-LASER DEPOSITION; ELECTRICAL-PROPERTIES; HETEROEPITAXIAL GROWTH AB For the first time, we have demonstrated that epitaxial Ba0.6Sr0.4TiO3 thin films can be grown on the epitaxial RuO2 electrodes by pulsed laser ablation. The Ba0.6Sr0.4TiO3 films, deposited on epitaxial (200) oriented RuO2 grown on (100) yttria-stabilized zirconia, exhibit single out-of-plane orientation as well as in-plane alignments. The detailed epitaxial relationships between the Ba0.6Sr0.4TiO3 films and the RuO2 electrodes have been analyzed by X-ray diffraction and transmission electron microscopy. C1 Univ Calif Los Alamos Natl Lab, Div Mat & Sci Technol, Los Alamos, NM 87545 USA. New Mexico Tech, Dept Mat Sci & Engn, Socorro, NM 87801 USA. RP Jia, QX (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat & Sci Technol, Mail Stop K763, Los Alamos, NM 87545 USA. RI Jia, Q. X./C-5194-2008 NR 9 TC 4 Z9 5 U1 0 U2 1 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 24 IS 1-4 BP 57 EP 63 DI 10.1080/10584589908215578 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290KD UT WOS:000085674700007 ER PT J AU Maiwa, H Maria, JP Christman, JA Kim, SH Streiffer, K Kingon, AI AF Maiwa, H Maria, JP Christman, JA Kim, SH Streiffer, K Kingon, AI TI Measurement and calculation of PZT thin film longitudinal piezoelectric coefficients SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE piezoelectric; AFM; PZT; composition; calculation; electrostriction ID LEAD-ZIRCONATE-TITANATE AB The ferroelectric and piezoelectric properties of 2000 Angstrom thick chemical solution deposited Pb(ZrxTi1-x)O-3 (PZT) thin films were investigated. Several Zr/Ti ratios were studied: 30/70, 50/50 and 65/35, which correspond to tetragonal, near-morphotropic, and rhombohedral symmetries. In all samples, a {111}-texture is predominant. Longitudinal piezoelectric coefficients and their de field dependence were measured using the contact AFM method. The expected trend of a maximum piezoelectric coefficient at or near to the MPB was not observed. The composition dependence was small, with the maximum d(33) occurring in the tetragonal material. To explain the results, crystallographic texture and film thickness effects are suggested. Using a modified phenomenological approach, derived electrostrictive coefficients, and experimental data, d33 Values were calculated. Qualitative agreement was observed between the measured and calculated coefficients. Justifications of modifications to the calculations are discussed. C1 N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Maiwa, H (reprint author), N Carolina State Univ, Dept Mat Sci & Engn, Box 7907, Raleigh, NC 27695 USA. NR 14 TC 24 Z9 24 U1 3 U2 10 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 24 IS 1-4 BP 139 EP 146 DI 10.1080/10584589908215586 PG 8 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290KD UT WOS:000085674700015 ER PT J AU Kozyrev, A Ivanov, A Prudan, A Soldatenkov, O Hollmann, E Loginov, V Ginley, D Rivkin, T AF Kozyrev, A Ivanov, A Prudan, A Soldatenkov, O Hollmann, E Loginov, V Ginley, D Rivkin, T TI Microwave phase shifter employing SrTiO3 ferroelectric varactors SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE ferroelectric varactor; phase shifter; tunable ID THIN-FILM AB Nonlinear microwave properties of thin SrTiO3 ferroelectric films at ambient temperatures were investigated. A tunability factor of 1.7 and loss tangent of about 0.01-0.015 were measured at frequencies of 2-10 GHz for SrTiO3 thin film planar varactors at room temperature. The performance of an X-band microstrip phase shifter employing the SrTiO3 planar varactors at room temperature is reported. Continuous phase shift in the range of (0-55) deg under bias voltage of 0-400 V at operating frequency band (8.6-9.0) GHz was observed. A figure of merit for the phase shifter is 110 deg/dB and the phase error is smaller than 5 deg. To our knowledge, it is the first demonstration of the microwave application of SrTiO3 varactors operating as nonlinear elements at room temperature and a record result for figure of merit for ferroelectric phase shifters. C1 St Petersburg Electrotech Univ, St Petersburg 197376, Russia. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kozyrev, A (reprint author), St Petersburg Electrotech Univ, Prof Popov ST 5, St Petersburg 197376, Russia. NR 10 TC 8 Z9 8 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 24 IS 1-4 BP 287 EP 295 DI 10.1080/10584589908215598 PG 9 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290KD UT WOS:000085674700027 ER PT J AU Kozyrev, AB Ivanov, AV Samoilova, TB Soldatenkov, OI Sengupta, LC Rivkin, TV Carlson, CM Parilla, PA Ginley, DS AF Kozyrev, AB Ivanov, AV Samoilova, TB Soldatenkov, OI Sengupta, LC Rivkin, TV Carlson, CM Parilla, PA Ginley, DS TI Microwave properties of ferroelectric (Ba,Sr)TiO3 varactors at high microwave power SO INTEGRATED FERROELECTRICS LA English DT Article; Proceedings Paper CT 11TH International Symposium on Integrated Ferroelectrics CY MAR 07-10, 1999 CL COLORADO SPRINGS, COLORADO DE ferroelectric; varactor; nonlinear; microwave AB The microwave (similar to 10 GHz) performance of a tunable resonator employing ferroelectric (Ba,Sr)TiO3 film planar varactors under exposure to high levels of microwave power was studied. The nonlinear characteristics of the ferroelectric films affected by the large signal microwave electrical field were evaluated. The limitations of high power performance for the films and tunable microwave devices based on the films were established. C1 St Petersburg Electrotech Univ, St Petersburg 197376, Russia. Paratek Microwave Inc, Aberdeen, MD 21001 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kozyrev, AB (reprint author), St Petersburg Electrotech Univ, Prof Popov ST 5, St Petersburg 197376, Russia. NR 6 TC 9 Z9 10 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 24 IS 1-4 BP 297 EP 307 DI 10.1080/10584589908215599 PG 11 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290KD UT WOS:000085674700028 ER PT J AU Sun, S Wang, YM Fuierer, PA Tuttle, BA AF Sun, S Wang, YM Fuierer, PA Tuttle, BA TI Annealing effects on the internal bias field in ferroelectric PZT thin films with self-polarization SO INTEGRATED FERROELECTRICS LA English DT Article DE ferroelectric films; internal bias; depolarization; hysteresis; asymmetry ID CERAMICS AB Asymmetric switching properties were measured and quantified in sol-gel derived PZT thin films. The hysteresis asymmetry is attributed to the presence of an internal bias field that has been correlated with the self-polarization during fabrication. Annealing the sample under a remanent polarization with the polarity opposite to that of self polarization can yield a partially compensated, completely canceled, or even a reversed internal bias, depending on the annealing temperature. Three dominant processes associated with charge trapping at elevated temperatures are clarified and correlated with the annealing effects. They are aging, de-aging, and the redistribution of trapped charges. A model using simplified domain configurations is proposed to explain the observed annealing effects on hysteresis asymmetry and switchable polarization. C1 New Mexico Inst Min & Technol, Dept Mat & Met Engn, Socorro, NM 87801 USA. Sandia Natl Labs, Elect Ceram Div, Albuquerque, NM 87185 USA. RP Sun, S (reprint author), Ramtron Int Corp, 1850 Ramtron Dr, Colorado Springs, CO 80921 USA. NR 15 TC 20 Z9 20 U1 0 U2 13 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1058-4587 J9 INTEGR FERROELECTR JI Integr. Ferroelectr. PY 1999 VL 23 IS 1-4 BP 25 EP 43 DI 10.1080/10584589908210138 PG 19 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 290KC UT WOS:000085674600003 ER PT S AU Gahagan, KT Gopalan, V Robinson, JM Jia, QX Mitchell, TE Kawas, MJ Schlesinger, TE Stancil, DD AF Gahagan, KT Gopalan, V Robinson, JM Jia, QX Mitchell, TE Kawas, MJ Schlesinger, TE Stancil, DD BE Righini, GC Najafi, SI TI Fabrication and characterization of high-speed integrated electro-optic lens and scanner devices SO INTEGRATED OPTICS DEVICES III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Integrated Optics Devices III CY JAN 25-27, 1999 CL SAN JOSE, CA SP SPIE, Def Adv Res Projects Agcy DE ferroelectrics; beam propagation method; integrated devices ID MATCHED 2ND-HARMONIC GENERATION; DOMAIN INVERSION; FIELD APPLICATION; BEAM DEFLECTOR; LITAO3; CRYSTALS; PROPAGATION; LINBO3 AB We demonstrate two high-speed electro-optic devices: an integrated lens/scanner and a variable radius collimating lens stack fabricated on a single crystal of Z-cut LiTaO3. The lens and scanner components consist of lithographically defined domain-inverted regions extending through the thickness of the crystal. A lens power of 0.233 cm(-1)kV(-1):, a deflection angle of 12.68 mad kV(-1), and a scan rate of 225 kHz at 375 V were observed. The collimating lens stack is theoretically capable of collimating the output from 2-10 micron diameter channel waveguides. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Gahagan, KT (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Stancil, Daniel/D-1339-2013; Jia, Q. X./C-5194-2008 OI Stancil, Daniel/0000-0002-2010-1381; NR 15 TC 5 Z9 5 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3090-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3620 BP 374 EP 379 DI 10.1117/12.343750 PG 6 WC Engineering, Electrical & Electronic; Optics; Physics, Applied; Telecommunications SC Engineering; Optics; Physics; Telecommunications GA BM84S UT WOS:000079917200041 ER PT J AU Unseren, MA AF Unseren, MA TI Brief overview of robotics and soft computing research at Oak Ridge National Laboratory SO INTELLIGENT AUTOMATION AND SOFT COMPUTING LA English DT Editorial Material C1 Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Oak Ridge, TN 37831 USA. RP Unseren, MA (reprint author), Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, POB 2008, Oak Ridge, TN 37831 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AUTOSOFT PRESS PI ALBUGUERQUE PA PO BOX 14126, ALBUGUERQUE, NM 87191-4126 USA SN 1079-8587 J9 INTELL AUTOM SOFT CO JI Intell. Autom. Soft Comput. PY 1999 VL 5 IS 1 BP 1 EP 3 PG 3 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA 173XF UT WOS:000079004500001 ER PT J AU Parker, LE AF Parker, LE TI Cooperative robotics for multi-target observation SO INTELLIGENT AUTOMATION AND SOFT COMPUTING LA English DT Article DE multi-robot cooperation; multi-target tracking; ALLIANCE; behavior-based AB An important issue that arises in the automation of many security, surveillance and reconnaissance tasks is that of observing (or monitoring) the movements of targets navigating in a bounded area of interest. A key research issue in these problems is that of sensor placement-determining where sensors should be located to maintain the targets in view. In complex applications involving limited-range sensors, the use of multiple sensors dynamically moving over time is required. In this article, we investigate the use of a cooperative team of autonomous sensor-based robots for the observation of multiple moving targets (a problem that we term CMOMMT). We focus primarily on developing the distributed control strategies that allow the robot team to attempt to maximize the collective time during which each target is being observed by at least one robot team member in the area of interest. Our initial efforts on this problem address the aspects of distributed control in robot teams with equivalent movement capabilities working in an uncluttered, bounded area This article first formalizes the problem and discusses related work. We then present a distributed approximate approach to solving this problem (called A-CMOMMT) that combines low-level multi-robot control with higher-level control. The low-level control is described in terms of force fields emanating from the targets and the robots. The higher level control is presented in our ALLANCE formalism[16,17], which provides mechanisms for fault tolerant cooperative control, and allows robot ream members to adjust their low-level actions based upon the actions of their teammates. We then present the results of the ongoing implementation of our approach, both in simulation and on physical robots. To our knowledge, this is the first article addressing this research problem that has been implemented on physical robot teams. C1 Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, POB 2008, Oak Ridge, TN 37831 USA. NR 23 TC 126 Z9 128 U1 1 U2 11 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA SN 1079-8587 EI 2326-005X J9 INTELL AUTOM SOFT CO JI Intell. Autom. Soft Comput. PY 1999 VL 5 IS 1 BP 5 EP 19 PG 15 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA 173XF UT WOS:000079004500002 ER PT J AU Rao, NSV AF Rao, NSV TI Fusion methods in multiple sensor systems using feedforward sigmoid neural networks SO INTELLIGENT AUTOMATION AND SOFT COMPUTING LA English DT Article DE sensor fusion; fusion rule estimation; empirical estimation; Lipschitz functions; feedforward neural networks ID NADARAYA-WATSON ESTIMATOR AB Consider a system of N sensors {S-1, S-2 ,... S-N}, where the sensor S-j outputs Y-(j) is an element of B, in response to input X is an element of R, according to an unknown probability distribution Py(jIX). A training n-sample (X-1, Y-1), (X-2, Y-2),.,., (X-n, Y-n) is given where Y-i= (Y-i((1)), Y-i((2)),..., Y-i((N))) and Y-i((j)) the output of S-j in response to input X-i is an element of R. The problem is to choose a fusion function f: R-N --> R from a family F, based on the sample, to minimize the expected square error I(f)= integral[x-f(Y)](2)dP(Y,X) where Y = (Y-(1), Y-(2), ...,Y-(N)) We consider F to be the set of feedforward neural networks of sigmoid units with a single hidden layer and bounded weights. The computation of f* is an element of F that exactly minimizes I(f) is not possible in general since the underlying distributions are unknown. Under the boundedness of X and Y, we show that for a sufficiently large sample, a neural network estimate (f) over cap can be obtained such that P[I((f) over cap)-I(f*) > epsilon] < delta for any epsilon > 0, delta, 0 < delta < 1, and any distribution P-y x. Using various properties of the feedforward neural networks we obtain three different estimates for the required sample sizes. C1 Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, POB 2008, Oak Ridge, TN 37831 USA. OI Rao, Nageswara/0000-0002-3408-5941 NR 22 TC 4 Z9 4 U1 0 U2 0 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA SN 1079-8587 EI 2326-005X J9 INTELL AUTOM SOFT CO JI Intell. Autom. Soft Comput. PY 1999 VL 5 IS 1 BP 21 EP 30 PG 10 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA 173XF UT WOS:000079004500003 ER PT J AU Pin, FG Bender, SR AF Pin, FG Bender, SR TI Adding memory processing behaviors to the fuzzy behaviorist approach (FBA): Resolving limit cycle problems in autonomous mobile robot navigation SO INTELLIGENT AUTOMATION AND SOFT COMPUTING LA English DT Article DE fuzzy control; sensor-based navigation; autonomous robot; fuzzy behaviorist approach; memory processing; limit cycle avoidance AB Most fuzzy logic-based reasoning schemes developed for robot control are fully reflexive, i.e., the reasoning modules consist of fuzzy rule bases mat represent direct mappings from the stimuli provided by the perception systems to the responses implemented by the motion controllers. Due to their totally reflexive nature, such reasoning systems can encounter problems such as infinite loops and limit cycles. In this paper. we propose an approach to remedy these problems by adding a memory and memory-related behaviors to basic reflexive systems. Three major types of memory behaviors are addressed: memory feeding, memory management, and memory utilization. The concepts underlying these major classes of behaviors are first presented. An example of their implementation is then described for the recognition of limit cycles during the sensor-based navigation of mobile robots. Results of sample cases involving an autonomous robot navigating in a priori unknown environments are presented and discussed to illustrate me efficiency of the approach. C1 Oak Ridge Natl Lab, Robot & Proc Syst Div, Oak Ridge, TN 37831 USA. RP Pin, FG (reprint author), Oak Ridge Natl Lab, Robot & Proc Syst Div, POB 2008, Oak Ridge, TN 37831 USA. NR 14 TC 16 Z9 16 U1 0 U2 0 PU AUTOSOFT PRESS PI ALBUGUERQUE PA PO BOX 14126, ALBUGUERQUE, NM 87191-4126 USA SN 1079-8587 J9 INTELL AUTOM SOFT CO JI Intell. Autom. Soft Comput. PY 1999 VL 5 IS 1 BP 31 EP 41 PG 11 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA 173XF UT WOS:000079004500004 ER PT J AU Baker, JE AF Baker, JE TI Providing accurate yet maximally consistent stochastic sampling for genetic algorithms SO INTELLIGENT AUTOMATION AND SOFT COMPUTING LA English DT Article DE Genetic Algorithms; selection sampling; evolutionary algorithms; stochastic bias AB Genetic Algorithms (GAs) are powerful global search techniques with application to a variety of engineering tasks, ranging from robotics to image processing. The power of the GA has long been associated with the implicit parallelism for which it is both necessary and sufficient to have an accurate Sampling Algorithm[5]. Although there has been significant research over the years in GA selection and sampling, previously available Sampling Algorithms have failed to simultaneously provide both accurate (zero biased) and consistent (minimal variance) sampling. This article reviews and empirically analyzes various sampling algorithms and offers two, time-efficient, maximally consistent algorithms: a partially parallel algorithm with increased accuracy and a completely accurate, sequential algorithm. C1 Oak Ridge Natl Lab, Robot & Proc Syst Div, Oak Ridge, TN 37831 USA. RP Baker, JE (reprint author), Oak Ridge Natl Lab, Robot & Proc Syst Div, POB 2008, Oak Ridge, TN 37831 USA. NR 30 TC 0 Z9 0 U1 0 U2 0 PU AUTOSOFT PRESS PI ALBUGUERQUE PA PO BOX 14126, ALBUGUERQUE, NM 87191-4126 USA SN 1079-8587 J9 INTELL AUTOM SOFT CO JI Intell. Autom. Soft Comput. PY 1999 VL 5 IS 1 BP 43 EP 56 PG 14 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA 173XF UT WOS:000079004500005 ER PT J AU Kress, RL Jansen, JF Love, LJ AF Kress, RL Jansen, JF Love, LJ TI Hydraulic manipulator design, analysis, and control at Oak Ridge National Laboratory SO INTELLIGENT AUTOMATION AND SOFT COMPUTING LA English DT Article DE robots; teleoperators; hydraulics; controls; nonlinearities ID SYSTEMS; IDENTIFICATION AB In the early developmental stages of robotics, hydraulics played an important role. Many of the early high-payload capacity manipulators were actuated by hydraulic cylinders and hydraulic rotary actuators. As the power-to-weight ratio of electric motors increased, they eventually came to be the preferred form of actuation for robotic manipulators because of the relative ease of operation, control, and maintenance for general cleanliness. Recently, however, task requirements have dictated that manipulator payload capacity increase to accommodate greater payloads, greater manipulator length, and larger environmental interaction forces. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem), sophisticated modeling. analysis, and control experiments are usually needed. Oak Ridge National Laboratory (ORNL) has a history of projects that incorporate hydraulics technology. including mobile robots, teleoperated manipulators, and full-scale construction equipment. The purpose of this article is to describe the hydraulic manipulator research capabilities at ORNL Included are experimental results from ORNL's teleoperated human-amplifier and a custom-designed hydraulic manipulator. C1 Oak Ridge Natl Lab, Robot & Proc Syst Div, Oak Ridge, TN 37831 USA. RP Kress, RL (reprint author), Oak Ridge Natl Lab, Robot & Proc Syst Div, POB 2008, Oak Ridge, TN 37831 USA. NR 28 TC 1 Z9 1 U1 0 U2 2 PU AUTOSOFT PRESS PI ALBUGUERQUE PA PO BOX 14126, ALBUGUERQUE, NM 87191-4126 USA SN 1079-8587 J9 INTELL AUTOM SOFT CO JI Intell. Autom. Soft Comput. PY 1999 VL 5 IS 1 BP 57 EP 71 PG 15 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA 173XF UT WOS:000079004500006 ER PT J AU Love, LJ Kress, RL Burks, B AF Love, LJ Kress, RL Burks, B TI Modeling teleoperated tank waste removal at Oak Ridge National Laboratory SO INTELLIGENT AUTOMATION AND SOFT COMPUTING LA English DT Article DE teleoperation; modeling; simulation AB One of the pervasive problems facing the Department of Energy's (DOE) national research facilities are the large volumes of stored radioactive waste. Historically, much of this waste, generated during the cold war, is contained in under ground storage tanks. Unfortunately, many of these tanks are showing signs of aging and fatigue. Subsequently, there is an aggressive DOE program directed at identifying existing technologies that can safely remove material from these facilities for storage in more stable environments. Oak Ridge National Laboratory (ORNL), teaming with industry and other laboratories, has designed, developed, and integrated a remotely operated waste removal system. This manuscript describes this system as well as the modeling and simulation effort performed prior to system integration and operation. The modeling effort includes a novel dynamic model of multiple robots coupled by an elastic hose. The result of a simulation study, presented in the latter part of the manuscript provides valuable insight into the operational strategies and limitations of the system. C1 Oak Ridge Natl Lab, Robot & Proc Syst Div, Oak Ridge, TN 37831 USA. RP Love, LJ (reprint author), Oak Ridge Natl Lab, Robot & Proc Syst Div, POB 2008, Oak Ridge, TN 37831 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU AUTOSOFT PRESS PI ALBUGUERQUE PA PO BOX 14126, ALBUGUERQUE, NM 87191-4126 USA SN 1079-8587 J9 INTELL AUTOM SOFT CO JI Intell. Autom. Soft Comput. PY 1999 VL 5 IS 1 BP 73 EP 85 PG 13 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA 173XF UT WOS:000079004500007 ER PT J AU Unseren, MA AF Unseren, MA TI Determination of contact forces for two manipulators mutually lifting a rigid object using a technique of dynamic load distribution (vol 2, pg 49, 1996) SO INTELLIGENT AUTOMATION AND SOFT COMPUTING LA English DT Correction C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Ctr Engn Sci Adv Res, Oak Ridge, TN 37831 USA. RP Unseren, MA (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Ctr Engn Sci Adv Res, POB 2008, Oak Ridge, TN 37831 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AUTOSOFT PRESS PI ALBUGUERQUE PA PO BOX 14126, ALBUGUERQUE, NM 87191-4126 USA SN 1079-8587 J9 INTELL AUTOM SOFT CO JI Intell. Autom. Soft Comput. PY 1999 VL 5 IS 3 BP 257 EP 258 PG 2 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA 244BA UT WOS:000083030900008 ER PT J AU Unseren, MA AF Unseren, MA TI Application of a load distribution technique for contact force magnitude limit avoidance when two manipulators mutually lift a rigid object (vol 3, pg 363, 1997) SO INTELLIGENT AUTOMATION AND SOFT COMPUTING LA English DT Correction C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Ctr Engn Sci Adv Res, Oak Ridge, TN 37831 USA. RP Unseren, MA (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Ctr Engn Sci Adv Res, POB 2008, Oak Ridge, TN 37831 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AUTOSOFT PRESS PI ALBUGUERQUE PA PO BOX 14126, ALBUGUERQUE, NM 87191-4126 USA SN 1079-8587 J9 INTELL AUTOM SOFT CO JI Intell. Autom. Soft Comput. PY 1999 VL 5 IS 3 BP 259 EP 261 PG 3 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA 244BA UT WOS:000083030900009 ER PT S AU Abidi, BR Sari-Sarraf, H Goddard, JS Hunt, MA AF Abidi, BR Sari-Sarraf, H Goddard, JS Hunt, MA BE Casasent, DP TI Facet model and mathematical morphology for surface characterization SO INTELLIGENT ROBOTS AND COMPUTER VISION XVIII: ALGORITHMS, TECHNIQUES, AND ACTIVE VISION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Intelligent Robots and Computer Vision XVIII - Algorithms, Techniques, and Active Vision CY SEP 20-21, 1999 CL BOSTON, MA SP SPIE DE facet model; mathematical morphology; real-time; surface characterization ID MACHINE; SYSTEM; PAPER AB This paper describes an algorithm for the automatic segmentation and representation of surface structures and non-uniformities in an industrial setting. The automatic image processing and analysis algorithm is developed as part of a complete on-line web characterization system of a papermaking process at the wet end. The goal is to: (1) link certain types of structures on the surface of the web to known machine parameter values, and (2) find the connection between detected structures at the beginning of the line and defects seen on the final product. Images of the pulp mixture (slurry), carried by a fast moving table, are obtained using a stroboscopic light and a CCD camera This characterization algorithm succeeded where conventional contrast and edge detection techniques failed due to a poorly controlled environment. The images obtained have poor contrast and contain noise caused by a variety of sources. After a number of enhancement steps, conventional segmentation methods still failed to detect any structures and are consequently discarded. Techniques tried include the Canny edge detector, the Sobel Roberts, and Prewitt's filters, as well as zero crossings. The facet model algorithm, is then applied to the images with various parameter settings and is found to be successful in detecting the various topographic characteristics of the surface of the slurry. Pertinent topographic elements are retained and a filtered image computed. Carefully tailored morphological operators are then applied to detect and segment regions of interest. Those regions are then selected according to their size, elongation, and orientation. Their bounding rectangles are computed and represented. Also addressed in this paper are aspects of the real time implementation of this algorithm for on-line use. The algorithm is tested on over 500 images of slurry and is found to segment and characterize nonuniformities on all 500 images. C1 Oak Ridge Natl Lab, Image Sci & Machine Vis Grp, Oak Ridge, TN 37831 USA. RP Abidi, BR (reprint author), Oak Ridge Natl Lab, Image Sci & Machine Vis Grp, Oak Ridge, TN 37831 USA. NR 31 TC 2 Z9 2 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3430-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3837 BP 334 EP 344 DI 10.1117/12.360312 PG 11 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Optics SC Automation & Control Systems; Computer Science; Optics GA BN92N UT WOS:000083488700034 ER PT S AU Schonfelder, B Keblinski, P Wolf, D Phillpot, SR AF Schonfelder, B Keblinski, P Wolf, D Phillpot, SR BE Lejcek, P Paidar, V TI On the relationship between grain-boundary migration and grain-boundary diffusion by molecular-dynamics simulation SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE structure-sensitive properties; grain-boundary migration; grain-boundary diffusion; molecular-dynamics simulation ID BICRYSTALS; METALS AB A molecular-dynamics method for the simulation of the intrinsic migration behavior of individual, flat grain boundaries is presented. A constant driving force for grain-boundary migration is generated by imposing an anisotropic elastic strain on a bicrystal such that the elastic-energy densities in its two halves are different. For the model case of the large-planar-unit-cell, high-angle (001) twist boundary in Cu we demonstrate that the drift velocity is proportional to the applied driving farce, thus enabling determination of the boundary mobility. The activation energy for grain-boundary migration is found to be distinctly lower than that for grain-boundary self-diffusion. A decrease in the related activation energies with increasing temperature is shown to arise from a crossover in the underlying mechanisms, from solid-like at low temperatures to liquid-like at high-temperatures that is accompanied by an underlying grain-boundary structural transition. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Rhein Westfal TH Aachen, Inst Met Kunde & Met Phys, D-52056 Aachen, Germany. RP Schonfelder, B (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Phillpot, Simon/J-9117-2012; OI Phillpot, Simon/0000-0002-7774-6535 NR 25 TC 11 Z9 11 U1 0 U2 3 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 9 EP 16 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000002 ER PT S AU Penisson, JM Lancon, F Dahmen, U AF Penisson, JM Lancon, F Dahmen, U BE Lejcek, P Paidar, V TI High resolution study of a quasiperiodic grain boundary in gold SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republ Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nucl Res Inst Rez, plc DE electron microscopy; atomic modeling; quasicrystals ID ATOMIC-STRUCTURE; TILT BOUNDARIES; SIMULATION; HREM AB A mazed bicrystal of gold has been obtained by vacuum deposition of gold onto a [001] germanium substrate. Amongst the different grain boundaries existing in this bicrystal, there exits facets which are completely assymetric and presenting a non periodic structure. It is shown that specific groups of atoms are present. Their spatial distribution along the boundary plane is analyzed. The diffractogram of the experimental high resolution images reveals the presence of intensity streaks in a non periodic distribution. The calculated structure of this boundary is in good agreement with the experimentally observed one. The complete analysis of the experimental results leads to the conclusion that this boundary represents a one dimensional quasi-crystal. C1 CEA, Dept Rech Fondamentales Mat Condensee, F-38054 Grenoble 9, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP CEA, Dept Rech Fondamentales Mat Condensee, 17 Ave Martyrs, F-38054 Grenoble 9, France. EM jpenisson@cea.fr RI Lancon, Frederic/B-2577-2009 OI Lancon, Frederic/0000-0002-6367-4462 NR 12 TC 10 Z9 10 U1 0 U2 2 PU TRANS TECH PUBLICATIONS LTD PI DURNTEN-ZURICH PA KREUZSTRASSE 10, 8635 DURNTEN-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 27 EP 34 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000004 ER PT S AU Medlin, DL Foiles, SM Campbell, GH Carter, CB AF Medlin, DL Foiles, SM Campbell, GH Carter, CB BE Lejcek, P Paidar, V TI Effect of grain boundary dislocations on 9R stacking errors at an incoherent twin boundary in copper SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE grain boundary dislocation; atomistic modeling; 9R; incoherent twin; stacking faults ID EMBEDDED-ATOM-METHOD; ELECTRON-MICROSCOPY; METALS; FCC; CU; TRANSFORMATION; AG AB We consider the nature of faults in the dissociated 9R phase at an incoherent twin boundary in copper, analysis of the dislocation content of a five-layer break in the normal ABC/BCA/CAB stacking sequence of the 9R shows that this defect is associated with a secondary grain boundary dislocation (SGBD) of Burgers vector a/6[(2) over bar 11]. Atomistic simulations of SGBDs at the incoherent twin interface show that the sign of the Burgers vector is important to determining the core structure of the dislocation. The resulting atomistic structures and the five-layer width of the fault can be directly understood by analyzing the set of twinning dislocations that make up the boundary. Atomistic calculations show further, in agreement with the experimental observations, that a shear parallel to the interface causes an increase in the fault width that accompanies the growth of the 9R phase. C1 Sandia Natl Labs, Ctr Mat Sci & Engn, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. RP Medlin, DL (reprint author), Sandia Natl Labs, Ctr Mat Sci & Engn, Livermore, CA 94550 USA. RI Campbell, Geoffrey/F-7681-2010; Carter, C. Barry/E-6478-2010; OI Carter, C. Barry/0000-0003-4251-9102; Foiles, Stephen/0000-0002-1907-454X NR 19 TC 7 Z9 7 U1 0 U2 2 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 35 EP 42 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000005 ER PT S AU Bruemmer, SM AF Bruemmer, SM BE Lejcek, P Paidar, V TI Grain boundary composition and effects on environmental degradation SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE grain boundary; segregation; IGSCC; corrosion; RIS; IASCC ID STRESS-CORROSION CRACKING; CHROMIUM DEPLETION; STAINLESS-STEEL; SEGREGATION AB Environmental degradation of metallic alloys is shown to depend on its local microstructure and microchemistry in many instances. Equilibrium and non-equilibrium processes can produce significant changes to the grain boundary composition and promote intergranular stress corrosion cracking (IGSCC). Austenitic stainless steels are used as an example to illustrate equilibrium effects of Gibbsian segregation and second-phase precipitation as well as non-equilibrium effects of quench-induced and radiation-induced segregation. Interfacial Cr concentration is shown to be the dominant material variable promoting IGSCC of austenitic stainless steels in oxidizing environments. Cracking susceptibility is a direct function of the boundary Cr content regardless of depletion width. However, grain boundary Cr depletion does not adequately explain IGSCC in stainless steels strengthened by cold work or neutron irradiation. Significant interfacial enrichment of Cr, Mo and B are often present in annealed stainless steels which may play a role in the IGSCC of cold-worked materials and delay IASCC to higher radiation doses. Impurity segregants (e.g., P) can promote IG hydrogen-induced cracking but do not have a strong detrimental effect on cracking in high-temperature water environments. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Bruemmer, SM (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 22 TC 6 Z9 6 U1 1 U2 2 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 75 EP 82 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000010 ER PT S AU Muller, DA Shashkov, DA Benedek, R Yang, LH Silcox, J Seidman, DN AF Muller, DA Shashkov, DA Benedek, R Yang, LH Silcox, J Seidman, DN BE Lejcek, P Paidar, V TI Atomic-scale studies of the electronic structure of ceramic/metal interfaces: {222}MgO/Cu SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE ceramic/metal heterophase interfaces; electron energy loss spectroscopy; local density functional theory; {111}MgO/Cu heterophase interfaces; electronic structure of interfaces ID HETEROPHASE INTERFACES AB {222} MgO/Cu interfaces produced by internal oxidation are studied by electron energy loss spectroscopy (EELS) using an atomic sized electron beam. We determine interfacial chemistry of this interface with subnanometer spatial resolution and use EELS to measure directly the electronic states pertaining to the buried interface. The O-K edge gives evidence of metal-induced gap states (MIGS) within the bandgap of MgO, at the interface, which we find to be O terminated. Both experiment and ab initio calculations show the MIGS to be strongly localized at the interface. C1 Cornell Univ, Sch Appl & Engn Phys, Ithaca, NY 14853 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Univ Calif Lawrence Livermore Natl Lab, Condensed Matter Phys Div, Livermore, CA 94551 USA. RP Muller, DA (reprint author), Cornell Univ, Sch Appl & Engn Phys, Ithaca, NY 14853 USA. RI Seidman, David/B-6697-2009; Muller, David/A-7745-2010 OI Muller, David/0000-0003-4129-0473 NR 11 TC 3 Z9 3 U1 0 U2 0 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 99 EP 102 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000014 ER PT S AU Johnson, E Johansen, A Dahmen, U Chen, SJ Fujii, T AF Johnson, E Johansen, A Dahmen, U Chen, SJ Fujii, T BE Lejcek, P Paidar, V TI Nanosized lead inclusions in aluminum-magic sizes and aspect ratios SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE edge energy; magic sizes; nanosized precipitates; Wulff construction ID PB INCLUSIONS; AL; SHAPES AB Aluminum-lead alloys containing dense distributions of nanosized lead precipitates have been made by rapid solidification and ion implantation. Embedded precipitates grow in parallel-cube alignment with the aluminum matrix; they have a cuboctahedral shape resulting from a minimization of the total interface energy, and atomically smooth {111} and {100} facets. The smallest precipitates, less than about 20 nm in size, adopt a series of magic sizes determined by periodic minima in the residual strain energy. In this size range the energy of the cuboctahedral edges becomes significant. This leads to changes in the aspect ratio of the precipitates so that the smaller precipitates are less truncated. Fitting the experimental data to an analytical expression gives a value of 1.15 for the ratio between the {100} and {111} interface energies and a value of 2.06.a(Pb) for the ratio of energies between the <110> edges and {111} interfaces. C1 Univ Copenhagen, Niels Bohr Inst, Orsted Lab, DK-2100 Copenhagen O, Denmark. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Johnson, E (reprint author), Univ Copenhagen, Niels Bohr Inst, Orsted Lab, Univ Pk 5, DK-2100 Copenhagen O, Denmark. RI Fujii, Toshiyuki/B-9555-2015 OI Fujii, Toshiyuki/0000-0001-9796-724X NR 15 TC 13 Z9 13 U1 0 U2 2 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 115 EP 118 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000018 ER PT S AU Ayache, J Thorel, A Kim, SJ Lesueur, J Westmacott, KH Dahmen, U AF Ayache, J Thorel, A Kim, SJ Lesueur, J Westmacott, KH Dahmen, U BE Lejcek, P Paidar, V TI Growth induced grain boundary plane oscillations in YBa2Cu3O7 thin film bicrystals SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE YBCO thin film superconductors; grain boundary; bicrystal; structure AB We have combined TEM (Transmission Electron Microscopy), HREM (High Resolution Electron Microscopy) and AFM (Atomic Force Microscope) techniques to study growth induced defects in YBCO thin film bicrystals. AFM images clearly evidence "in-plane waviness" of the grain boundary (GB) and a quantitative analysis of HREM images shows unambiguously the oscillation of the grain boundary plane, This GB structure and morphology results from the island growth mechanism of the film. C1 Univ Paris 11, CNRS, CSNSM, F-91405 Orsay, France. Ecole Mines Paris, Ctr Mat, F-91003 Evry, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Ayache, J (reprint author), Univ Paris 11, CNRS, CSNSM, F-91405 Orsay, France. NR 5 TC 0 Z9 0 U1 1 U2 2 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 119 EP 122 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000019 ER PT S AU Chisholm, MF Maiti, A Pennycook, SJ Pantelides, ST AF Chisholm, MF Maiti, A Pennycook, SJ Pantelides, ST BE Lejcek, P Paidar, V TI Vacancy formation and vacancy-induced structural transformation in Si grain boundaries SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE electron microscopy; grain boundary structure; vacancy formation; Z-contrast ID SILICON AB Atomic resolution Z-contrast scanning transmission electron microscopy reveals preferential nucleation of electron-beam-induced damage in select atomic columns of a Si tilt grain boundary. Atomic scale simulations find that the region of initial damage nucleation corresponds to columns where the formation energies of vacancies and vacancy complexes are very low. The calculations further predict that vacancy accumulation in certain pairs of columns can induce structural transformations of the grain boundary core region. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RP Chisholm, MF (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 12 TC 9 Z9 11 U1 0 U2 4 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 161 EP 164 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000029 ER PT S AU Babcock, SE Yang, CY Reeves, JL Wu, Y Pashitski, AE Polyanskii, A Larbalestier, DC Goyal, A Paranthaman, M List, FA Norton, DP Kroeger, DM Ichinose, A AF Babcock, SE Yang, CY Reeves, JL Wu, Y Pashitski, AE Polyanskii, A Larbalestier, DC Goyal, A Paranthaman, M List, FA Norton, DP Kroeger, DM Ichinose, A BE Lejcek, P Paidar, V TI Electromagnetic connectivity and microstructure in YBa2Cu3O7-delta films on rolling-assisted biaxially-textured substrates SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE coated conductors; RABiTS (TM); buffer layers; YSZ; YBa2Cu3O7-delta; electron microscopy; magneto optic imaging; critical current density; granularity ID ELECTRON-BEAM EVAPORATION; CRITICAL-CURRENT DENSITY; SUPERCONDUCTING TAPES; BUFFER LAYERS; NI AB Biaxially-textured YBa2Cu3O7-delta (YBCO) coated conductors are a central thrust of current efforts to fabricate high-critical-current-density (J(c)) wire for large-scale applications of high-T-c superconductivity. Encouragingly high J(c) values are obtained in laboratory-length samples. However, magneto-optic imaging indicates that the supercurrent path is percolative even in the best materials. Thus, it seems clear that the full potential current carrying capability of these composites has not been reached, This paper describes coupled magneto-optic imaging and microstructural studies of RABiTS(TM) type coated conductors that indicate (1) the important roles of other microstructural features in addition to grain boundaries and (2) the need to explore the roles of the oxide buffer layer microstructure in optimizing the composite. C1 Univ Wisconsin, Mat Sci & Engn & Appl Superconduct Ctr, Madison, WI 53706 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Cent Res Inst Elect Power Ind, Tokyo, Japan. RP Babcock, SE (reprint author), Univ Wisconsin, Mat Sci & Engn & Appl Superconduct Ctr, 1500 Engn Dr, Madison, WI 53706 USA. RI Polyanskii, Anatolii/B-8794-2009; Larbalestier, David/B-2277-2008; Paranthaman, Mariappan/N-3866-2015 OI Larbalestier, David/0000-0001-7098-7208; Paranthaman, Mariappan/0000-0003-3009-8531 NR 11 TC 0 Z9 0 U1 0 U2 0 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 165 EP 168 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000030 ER PT S AU Campbell, GH King, WE Foiles, SM Cohen, D AF Campbell, GH King, WE Foiles, SM Cohen, D BE Lejcek, P Paidar, V TI Determination of grain boundary atomic structure using quantitative high resolution electron microscopy SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE quantitative high resolution electron microscopy; least-squares optimization; grain boundaries; atomic structure determination ID SIMULATION; ALUMINUM AB Quantitative high resolution electron microscopy has been used to study the atomic structure of grain boundaries in metals. An example of the Sigma 11 (113)/[140] symmetric tilt grain boundary in Al is given. Results for atomic column locations were compared quantitatively with atomistic simulations of the structure of the grain boundary using Embedded Atom Method (EAM) potentials and Local Density Approximation (LDA) methods. There is a statistically significant difference between the experimental image and the simulated image based on the EAM. The experimentally determined grain boundary structure is in better agreement with the LDA calculation. C1 Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. Sandia Natl Labs, Livermore, CA 94550 USA. RP Campbell, GH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. RI Campbell, Geoffrey/F-7681-2010; OI Foiles, Stephen/0000-0002-1907-454X NR 13 TC 0 Z9 0 U1 0 U2 2 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 293 EP 296 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000061 ER PT S AU Luzzi, DE Imamura, D Inui, H George, EP Heatherly, L Yasuda, H Mori, H Yamaguchi, M AF Luzzi, DE Imamura, D Inui, H George, EP Heatherly, L Yasuda, H Mori, H Yamaguchi, M BE Lejcek, P Paidar, V TI Auger spectroscopy of TiAl interface diffusion specimens SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE interface diffusion; TiAl; Auger electron spectroscopy AB The utility of polysynthetically-twinned (PST) TiAl, which contains a high density of parallel, atomically-fiat interfaces within a set of identical crystallographic orientations, as a potential model system for a detailed investigation of interface diffusion is explored. Macroscopic PST crystals were grown in an optical float zone furnace. Thin films were cut from oriented crystals and polished with <110> and <112> directions normal to the film. After sputter cleaning, Ag was deposited on one side of the TiAl thin films. Auger spectra were obtained from these films over a wide range of sputter/anneal conditions. The Al and Ti concentrations were analyzed as well as the important impurity elements, S, Ar, C, N and O. Ag diffusion on the interfaces was confirmed. Using the present data and existing knowledge of the microstructure and crystallography of PST TiAl, the potential of this material for providing a detailed understanding of the atomistic mechanisms of interface diffusion is analyzed. C1 Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Kyoto Univ, Dept Mat Sci & Engn, Kyoto 60601, Japan. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Osaka Univ, Res Ctr Ultra High Voltage Electron Microscopy, Suita, Osaka 565, Japan. RP Luzzi, DE (reprint author), Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. RI George, Easo/L-5434-2014 NR 6 TC 0 Z9 0 U1 0 U2 1 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 389 EP 392 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000085 ER PT S AU Wolverton, C AF Wolverton, C BE Lejcek, P Paidar, V TI First-principles theory of coherent precipitation in size-mismatched SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE first-principles theory; precipitation; coherency strain; Al-Cu; Al-Mg AB A first-principles thermodynamic approach for studying coherent precipitation in size-mismatched alloys is presented. The approach takes into account both strain and interfacial energies, incorporates the effects of finite temperature, and can treat systems with length scales of similar to 200 Angstrom, all with first-principles accuracy. The method is applied to coherent precipitation in Al-Cu and Al-Mg alloys, where the coherent precipitation sequence is experimentally well-studied, but still controversial. This theoretical approach should aid in understanding the strengthening mechanism underlying precipitation hardening in these materials. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wolverton, C (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Wolverton, Christopher/B-7542-2009 NR 8 TC 0 Z9 0 U1 1 U2 3 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 469 EP 472 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000104 ER PT S AU Moody, NR Strojny, A Medlin, D Schneider, J Talin, A Gerberich, WW AF Moody, NR Strojny, A Medlin, D Schneider, J Talin, A Gerberich, WW BE Lejcek, P Paidar, V TI Interface structure effects on the fracture of hard thin films SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE interface structure; interfacial fracture; tantalum nitride films; aluminum nitride substrates; aluminum oxide substrates ID ADHESION AB In this study we combined nanoscratch testing with a multi-layer aluminum oxide and aluminum nitride single substrate system to determine the effects of interface composition and structure on susceptibility to fracture of hard, thin tantalum nitride films. Nanoscratch tests showed that the film on aluminum oxide and on aluminum nitride portions of the substrate failed readily along the tantalum nitride film-substrate interface regardless of substrate composition. Most importantly, the fracture energies were essentially equal on both substrate materials. These results strongly suggest that a sputter deposited interface structure controls susceptibility to fracture. C1 Sandia Natl Labs, Livermore, CA 94550 USA. Univ Minnesota, Minneapolis, MN USA. Motorola Inc, Tempe, AZ USA. RP Moody, NR (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 8 TC 0 Z9 0 U1 0 U2 2 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 633 EP 636 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000145 ER PT S AU Simonen, EP Bruemmer, SM AF Simonen, EP Bruemmer, SM BE Lejcek, P Paidar, V TI Radiation-induced grain boundary segregation in austenitic stainless steels SO INTERGRANULAR AND INTERPHASE BOUNDARIES IN MATERIALS, IIB98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 9th International Conference on Intergranular and Interphase Boundaries in Materials (iib98) CY JUL 06-09, 1998 CL PRAGUE, CZECH REPUBLIC SP Czech Republic Acad Sci Inst Phys, Union Czech Math & Physicists, European Commiss, DG XII, Sci, Res & Dev, Off Naval Res Int Field Off - Europe & European Off Aerosp Res & Dev, VITKOVICE, a s, AR Tour Ondracek, Magnox Electric, plc, Nuclear Res Inst Rez, plc DE grain boundaries; segregation; RIS; IASCC AB Radiation-induced segregation to grain boundaries in austenitic stainless steels has been evaluated for a wide range of solute species, temperatures, irradiation dose and dose rate, and irradiation particle type. The primary findings from measurement and modeling are that major alloying elements (Fe, Ni and Cr) segregate predominately by the inverse-Kirkendall mechanism and undersized minor elements segregate by the interstitial-association mechanism. Several hundred measurements of radiation-induced grain boundary composition have been analyzed and rate theory models of solute-point defect interactions are shown to be useful descriptors of the segregation process. This fundamental study of segregation has aided the definition of grain boundary microchemistry during exposure to neutron irradiation in power reactors and relates to the specific problem of irradiation-assisted stress corrosion cracking. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Simonen, EP (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 8 TC 1 Z9 1 U1 1 U2 6 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-823-0 J9 MATER SCI FORUM PY 1999 VL 294-2 BP 755 EP 758 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM90M UT WOS:000080081000175 ER PT J AU Hong, S Fu, CL AF Hong, S Fu, CL TI Phase stability and elastic moduli of Cr2Nb by first-principles calculations SO INTERMETALLICS LA English DT Article DE Cr2Nb Laves phases; phase stability; first-principles calculations; FLAPW; elastic properties ID ELECTRONIC-STRUCTURE; TOTAL-ENERGY; CONSTANTS; NBCR2 AB The phase stability and elastic moduli of Cr2Nb are investigated by first-principles calculations. Heats of formation are calculated and compared for the three Laves phases (C15, C14, and C36). It is found that the C15 phase is the ground-state structure with the lowest energy and the C36 phase is an intermediate state between C15 and C14. These three phases, however, are very close in energy, indicating low stacking fault energies in this system. For the ground-state C15 phase, we calculate three elastic constants from which the shear and Young's moduli are obtained. It is found that these calculated moduli are smaller than the experimental values obtained from polycrystals. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Hong, S (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 12 TC 67 Z9 68 U1 0 U2 6 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0966-9795 J9 INTERMETALLICS JI Intermetallics PD JAN PY 1999 VL 7 IS 1 BP 5 EP 9 DI 10.1016/S0966-9795(98)00005-3 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 146EL UT WOS:000077415000002 ER PT B AU Letellier, B Restrepo, L Shaffer, CJ AF Letellier, B Restrepo, L Shaffer, CJ GP AICHE AICHE TI Near-field dispersion of fission products in complex terrain using a 3-D turbulent fluid-flow model SO INTERNATIONAL CONFERENCE AND WORKSHOP ON MODELING THE CONSEQUENCES OF ACCIDENTAL RELEASES OF HAZARDOUS MATERIALS LA English DT Proceedings Paper CT International Conference and Workshop on Modeling the Consequences of Accidental Releases of Hazardous Materials CY SEP 28-OCT 01, 1999 CL SAN FRANCISCO, CA SP Amer Inst Chem Engineers, Ctr Chem Proc Safety, Amer Petr Inst, Chem Safety & Hazard Investigat Board, US EPA, Amer Nucl Soc, Div Environm Sci, European Federat Chem Engn, European Proc Safety Ctr, Hlth & Safety Execut, US DOE AB A recent safety analysis effort at Los Alamos National Laboratory involved a postulated release of fission products from the ventilation system of a building located near the wall of a canyon that is lined with fir trees. At immediate exposure risk from this accident are security personnel stationed within 50 and 150 m from the building. The variety of time scales and phenomenology present in this scenario required the integration of several analysis tools: (1) the ORIGEN2 nuclear-activation and decay model was used to compute time-dependent fission-product inventories following a criticality excursion in a ;nuclear assembly, (2) the MELCOR reactor-containment model was used to predict thermal and pressure-driven exfiltration rates of gases and aerosols from a building having door-seal gaps and ventilation outlets, (3) the FLOW-3D (Flow Science, Inc. Los Alamos, NM) turbulent fluid-flow model was used to transport material from roof-level vents through a complex building wake in order to determine time-dependent air concentrations near the receptor locations, and (4) a post-processing utility was developed to perform integrals over release and exposure times and to compute internal and external radiation doses. This paper is focused on the near-field transport of fission products in the presence of building wake and terrain obstacles. A brief description of the dose-integration methodology is also given. The FLOW-3D fluid model provides a general capability for finding three-dimensional, time-dependent Navier-Stokes solutions to fluid transport problems in a wide variety of aerodynamic and hydrodynamic design/analysis applications. This code provides boundary conditions such as constant or time-dependent directional flows, obstacle properties such as roughness and heat generation, and transport mechanisms such as particulate settling and diffusion that are necessary for facility-safety consequence analyses. FLOW-SD was successfully used to model turbulent wind fields near a two-level building and a canyon wall and to predict downwind air concentrations for a puff of tracer material released from elevated ventilation outlets. Resolutions of approximately 1 m were applied in a graduated spatial grid containing approximately 125,000 cells over the domain of interest. Steady-state solutions for uniformly incident winds were obtained in less than 45 CPU hours on a 450-MHz desktop processor. Comparisons of 3-D concentrations near a cubical building placed in free-field, uniform winds were made with correlations available from experiment for this simple configuration to benchmark performance of the numerical model against familiar results. Then, the FLOW-3D model was applied to an idealized configuration consisting of a large building sitting in a niche against a canyon wall. Animations of puff releases illustrate the effects of wind speed and upstream obstacles on the behavior of the turbulent plume. Finally, air-concentration histories observed at selected receptor locations were integrated with time-dependent source terms to estimate total exposures over the duration of an accident scenario. II was found that the combination of nuclear decay and building holdup times can greatly affect near-field radiation doses at early exposure times. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Letellier, B (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 10 TC 0 Z9 0 U1 0 U2 2 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-8169-0781-1 PY 1999 BP 381 EP 396 PG 16 WC Engineering, Environmental; Engineering, Chemical; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BP49X UT WOS:000085324900020 ER PT B AU Fthenakis, VM Rohatgi, US AF Fthenakis, VM Rohatgi, US GP AICHE AICHE TI Modeling of underwater liquid releases, slick transport, and evaporation SO INTERNATIONAL CONFERENCE AND WORKSHOP ON MODELING THE CONSEQUENCES OF ACCIDENTAL RELEASES OF HAZARDOUS MATERIALS LA English DT Proceedings Paper CT International Conference and Workshop on Modeling the Consequences of Accidental Releases of Hazardous Materials CY SEP 28-OCT 01, 1999 CL SAN FRANCISCO, CA SP Amer Inst Chem Engineers, Ctr Chem Proc Safety, Amer Petr Inst, Chem Safety & Hazard Investigat Board, US EPA, Amer Nucl Soc, Div Environm Sci, European Federat Chem Engn, European Proc Safety Ctr, Hlth & Safety Execut, US DOE AB This paper presents an application of fluid mechanics in calculating the leakage of a fluid from a vessel submerged in a river, lake or the ocean. A model is developed to determine leakage due to changes of gravity and pressure forces caused by movements of the vessel or waves at the surface and of the spread of the spill on the water surface with evaporation. The equations in the model are solved analytically, and the solution is tested for the sensitivity of its predictions to the variation of input data. The model's predictions of discharges due to differences in hydrostatic pressure are verified with experimental data. Finally, the model is applied to a known case of gasoline leakage from an overturned barge in a river. C1 Brookhaven Natl Lab, Dept Adv Technol, Upton, NY 11973 USA. RP Fthenakis, VM (reprint author), Brookhaven Natl Lab, Dept Adv Technol, Upton, NY 11973 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-8169-0781-1 PY 1999 BP 397 EP 417 PG 21 WC Engineering, Environmental; Engineering, Chemical; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BP49X UT WOS:000085324900021 ER PT B AU May, JM de Supinski, BR AF May, JM de Supinski, BR BE Arabnia, HR TI Experience with mixed MPI/threaded programming models SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOL VI, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE shared memory clusters; programming models; threads; message passing AB Shared memory clusters are hybrid parallel computers that support mixed programming models. Mixed models combine message passing with some form of multithreading, such as explicit thread calls, compiler parallelization based on directives, or threaded libraries. Although applications can treat these clusters as pure message passing machines, doing so may harm performance or prevent the code from using the full capabilities of the machine. We surveyed developers of several mixed model scientific applications at Lawrence Livermore National Laboratory to learn about their experiences with these models. All the codes we surveyed use MPI for message passing, but they use a variety of techniques for multithreading. This paper describes how the applications use mixed models and how easy the models were to program. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP May, JM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, 7000 East Ave,L-561, Livermore, CA 94551 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-14-9 PY 1999 BP 2907 EP 2912 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BP04U UT WOS:000083968700037 ER PT B AU Wu, KS Simon, H AF Wu, KS Simon, H BE Arabnia, HR TI An evaluation of the parallel shift-and-invert Lanczos method SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOL VI, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE eigenvalue; Lanczos algorithm; parallel direct method ID SPARSE AB When the Lanczos method is used to compute eigenvalues, it is often restarted or used with the shift-and-invert scheme. The restarted scheme usually uses less memory but the shift-and-invert scheme is more robust. In addition, the shift-and-invert Lanczos method requires accurate solutions of a series of linear systems. Parallel software packages suitable for these linear systems are only started to become available. In this talk, we will present our evaluation of two such packages and briefly exam when it is necessary to use the shift and-invert scheme. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. RP Wu, KS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-14-9 PY 1999 BP 2913 EP 2919 PG 7 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BP04U UT WOS:000083968700038 ER PT B AU Vajracharya, S Beckman, P Karmesin, S Keahey, K Oldehoeft, R Rasmussen, C AF Vajracharya, S Beckman, P Karmesin, S Keahey, K Oldehoeft, R Rasmussen, C BE Arabnia, HR TI A programming model for clusters of SMPs SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOLS I-V, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE programming models; data-parallel; run-time systems; loop scheduling; macro-dataflow; cache reuse ID PARALLEL AB High-performance computing on clusters of shared-memory multiprocessors (SMPs) is becoming a popular solution to large-scale numerical computation. While the potential for unprecedented computing power at small casts exists, the challenge of making effective use of the deep memory hierarchies an these clusters overwhelms the application programmer, who must consider the location of data in the processor cache, remote memory within an SMP, and remote memory across SMPs. Furthermore, what programming model maps well over multi-level memory hierarchies that extend to remote boxes? SPMD? Work queues using threads? In this paper, we present a unifying graph-based model of programming to address the challenge of data locality and parallelism on clusters of SMPs. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Vajracharya, S (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-15-7 PY 1999 BP 424 EP 431 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Mathematics, Applied SC Computer Science; Engineering; Mathematics GA BR81L UT WOS:000167653300063 ER PT B AU Petrini, F Bassetti, F Gerbessiotis, A AF Petrini, F Bassetti, F Gerbessiotis, A BE Arabnia, HR TI A new approach to parallel program development and scheduling of parallel jobs on distributed systems SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOLS I-V, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE parallel job scheduling; communication libraries; run-time support; operating systems AB A typical way to increase the performance of a parallel program on a given parallel platform is to try to overlap computation and communication in order to decrease running time and simultaneously increase efficiency (speedup). This approach, however, leads to diminishing returns after an initial and time-consuming development phase. We propose an alternative approach to program development and resource utilization in a parallel machine. Rather than increasing the complexity of a single program, we attempt to overlap the execution of two or more parallel jobs on the same machine. Though this approach is not new, we think that the adoption of one-sided communication in program development and global scheduling strategies can pave the way to a new methodology of developing parallel programs that are simpler and can use more efficiently a wide range of parallel machines and distributed systems. This methodology is based on three innovative techniques communication buffering, strobing, and non-blocking, one-sided communication. By leveraging these techniques, we can perform effective optimizations based on the status of the parallel machine rather than on the limited knowledge available locally to each processor. C1 Univ Calif Los Alamos Natl Lab, Sci Comp Grp CIC19, Los Alamos, NM 87545 USA. RP Petrini, F (reprint author), Univ Calif Los Alamos Natl Lab, Sci Comp Grp CIC19, Los Alamos, NM 87545 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-15-7 PY 1999 BP 546 EP 552 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Mathematics, Applied SC Computer Science; Engineering; Mathematics GA BR81L UT WOS:000167653300080 ER PT B AU Hoffman, FM Hargrove, WW AF Hoffman, FM Hargrove, WW BE Arabnia, HR TI Multivariate geographic clustering using a Beowulf-style parallel computer SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOLS I-V, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE multivariate geographic clustering; Beowulf; load balancing; fault tolerance AB The authors present an application of multivariate non-hierarchical statistical clustering to geographic environment data from the 48 conterminous United States in order to produce maps of regions of ecological similarity called ecoregions. Nine input variables thought to affect the growth of vegetation are clustered at a resolution of one square kilometer. These data represent over 7.8 million map cells in a 9-dimensional data space. For the analysis, the authors built a 126-node heterogeneous cluster-aptly named Me Stone SouperComputer-out of surplus PCs. The authors developed a parallel iterative statistical clustering algorithm which uses the MPI message passing routines, employs a classical master/slave single program multiple data (SPMD) organization, performs dynamic load balancing, and provides fault tolerance. In addition to being ran on the Stone SouperComputer, the parallel algorithm was tested on other parallel platforms without code modification. Finally, the results of the geographic clustering are presented. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Hoffman, FM (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Hoffman, Forrest/B-8667-2012 OI Hoffman, Forrest/0000-0001-5802-4134 NR 11 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-15-7 PY 1999 BP 1292 EP 1298 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Mathematics, Applied SC Computer Science; Engineering; Mathematics GA BR81L UT WOS:000167653300191 ER PT B AU Bassetti, F Davis, K AF Bassetti, F Davis, K BE Arabnia, HR TI Optimizing transformations of stencil operations for parallel cache-based architectures SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOLS I-V, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE parallel stencil operations; optimization; cache-based architectures AB This paper describes a new technique for optimizing serial and parallel stencil- and stencil-like operations for cache-based architectures. This technique tales advantage of the semantic knowledge implicitly in stencil-like computations. The technique is implemented as a source-to-source program transformation; because of its specificity it could not be expected of a conventional compiler. Empirical results demonstrate a uniform factor of two speedup. The experiments clearly show the benefits of this technique to be a consequence, as intended, of the reduction in cache misses. The test codes are based on a 5-point stencil obtained by the discretization of the Poisson equation and applied to a two-dimensional uniform grid using the Jacobi method as an iterative solver. Results are presented for a 1-D and 2-D tiling for a single processor. For the parallel case both blocking and non-blocking communication have been tested. However, the parallel case is not discussed here. C1 Univ Calif Los Alamos Natl Lab, Sci Comp Grp, Los Alamos, NM 87545 USA. RP Bassetti, F (reprint author), Univ Calif Los Alamos Natl Lab, Sci Comp Grp, POB 1663,CIC-19, Los Alamos, NM 87545 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-15-7 PY 1999 BP 1343 EP 1349 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Mathematics, Applied SC Computer Science; Engineering; Mathematics GA BR81L UT WOS:000167653300199 ER PT B AU Bresnahan, J Foster, I Insley, J Toonen, B Tuecke, S AF Bresnahan, J Foster, I Insley, J Toonen, B Tuecke, S BE Arabnia, HR TI Communication services for advanced network applications SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOLS I-V, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE network applications; communication libraries; Nexus; Collaboratory Interoperability Framework (CIF) AB Advanced network applications such as remote instrument control, collaborative environments, and remote I/O are distinguished from "traditional" applications such as videoconferencing by their need to create multiple, heterogeneous pours with different characteristics. For example, a single application may require remote I/O for raw datasets, shared controls for a collaborative analysis system, streaming video for image rendering data, and audio for collaboration. Furthermore, each pow can have different requirements in terms of reliability, network quality of service, security, etc. We argue that new approaches to communication services, protocols, and network architecture are required both to provide high-level abstractions for common pour types and to support user-level management of pour creation and quality, We describe experiences with the development of such applications and communication services. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Bresnahan, J (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-15-7 PY 1999 BP 1861 EP 1867 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Mathematics, Applied SC Computer Science; Engineering; Mathematics GA BR81L UT WOS:000167653300275 ER PT B AU de Supinski, BR May, J AF de Supinski, BR May, J BE Arabnia, HR TI Benchmarking Pthreads performance SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOLS I-V, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc AB The importance of the performance of threads libraries is growing as clusters of shared memory machines become more popular. Posix threads, or Pthreads, is an industry threads library standard. We have implemented the first Pthreads benchmark suite. In addition to measuring basic thread functions, such as thread creation, we apply the LogP model to standard Pthreads communication mechanisms. We present the results of our tests for several hardware platforms. These results demonstrate that the performance of existing Pthreads implementations varies widely; parts of nearly all of these implementations could be further optimized. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP de Supinski, BR (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-15-7 PY 1999 BP 1985 EP 1991 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Mathematics, Applied SC Computer Science; Engineering; Mathematics GA BR81L UT WOS:000167653300294 ER PT B AU Freitag, LA Gropp, WD Hovland, PD McInnes, LC Smith, BF AF Freitag, LA Gropp, WD Hovland, PD McInnes, LC Smith, BF BE Arabnia, HR TI Infrastructure and interfaces for large-scale numerical software SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOLS I-V, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE high-performance scientific computing; component software; nonlinear PDEs AB The complexity of large-scale scientific simulations often necessitates the combined use of multiple software packages developed by different groups in areas such as adaptive mesh manipulations, scalable algebraic solvers, and optimization. Historically, these packages have been combined by using custom. code. This practice inhibits experimentation with and comparison of multiple tools that provide similar functionality through different implementations. The ALICE project, a collaborative effort among researchers at Argonne National Laboratory, is exploring the use of component-based software engineering to provide better interoperability among numerical toolkits. We discuss some initial experiences in developing an infrastructure and interfaces for high-performance numerical computing. C1 Argonne Natl Lab, Math & Comp Sci Div, Argonne, IL 60439 USA. RP Argonne Natl Lab, Math & Comp Sci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. EM freitag@mcs.anl.gov; gropp@mcs.anl.gov; hovland@mcs.anl.gov; mcinnes@mcs.anl.gov; bsmith@mcs.anl.gov NR 18 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-15-7 PY 1999 BP 2657 EP 2663 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Mathematics, Applied SC Computer Science; Engineering; Mathematics GA BR81L UT WOS:000167653300397 ER PT B AU Plasil, F AF Plasil, F BE Lellouch, D Mikenberg, G Rabinovici, E TI High energy nuclear collisions SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM ID HEAVY-ION COLLISIONS; QUARK-GLUON PLASMA; LOW-MASS DILEPTONS; SUPPRESSION; ENHANCEMENT; PHOTONS; GEV/C AB The field of nucleus-nucleus collisions at "ultrarelativistic" energies is surveyed with emphasis on photon and lepton measurements. Prospects for future experiments at the Relativistic Heavy Ion Collider and the Large Hadron Collider are discussed. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Plasil, F (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 166 EP 175 PG 10 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100014 ER PT B AU Muller, D AF Muller, D CA SLD Collaboration BE Lellouch, D Mikenberg, G Rabinovici, E TI New tests of QCD using Z(0) -> b(b)over-barg events SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM ID ENERGY AB We present new studies of 3-jet final states from hadronic Z(0) decays recorded by the SLD experiment, in which the quark, antiquark, and gluon jets are identified. Our gluon energy spectrum, measured over the full kinematic range, is consistent with the predictions of QCD, and we derive a Limit on an anomalous chromomagnetic bbg coupling. We measure the parity violation in Z(0) decays into b(b) over bar g to be consistent with the predictions of electroweak theory and QCD, and perform new tests of T- and CP-conservation at the bbg vertex. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Muller, D (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 501 EP 504 PG 4 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100068 ER PT B AU Buckley-Geer, E AF Buckley-Geer, E CA CDF Collaboration BE Lellouch, D Mikenberg, G Rabinovici, E TI Hard processes and perturbative QCD results from CDF SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM ID PROTON-ANTIPROTON COLLIDER; HADRON COLLIDERS; (P)OVER-BAR-P COLLISIONS; MULTIJET EVENTS; CROSS-SECTION; JET; MASS AB We present results on the inclusive jet cross section at root s = 1800 GeV and 630 GeV, the two-jet cross section, multijet physics and the multijet differential cross section from the CDF experiment at the Fermilab Tevatron Collider. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Buckley-Geer, E (reprint author), Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. NR 12 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 526 EP 529 PG 4 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100074 ER PT B AU Strovink, M AF Strovink, M CA DO Collaboration BE Lellouch, D Mikenberg, G Rabinovici, E TI Top quark results from D SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM AB This is a brief summary of D empty set's top quark measurements, including sigma t (t) over bar and m(t) in the l+jets and dilepton channels, sigma(t (t) over bar) in the all jets channel, and the search for top disappearance via t-->bH(+), H+ --> tau nu or c (s) over bar. C1 Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Strovink, M (reprint author), Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 585 EP 588 PG 4 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100089 ER PT B AU Yu, JH AF Yu, JH BE Lellouch, D Mikenberg, G Rabinovici, E TI Precision electroweak results from N-N scattering in CCFR/NuTeV SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM ID MIXING ANGLE; NEUTRINO AB We present a recent precision electroweak result from nu-N scattering experiment at CCFR. The latest measurement of the weak mixing angle from the CCFR experiment is sin(2) theta(w) = 0.2236 +/- 0.0041 which corresponds to on-shell mass of the W boson, M-w = 80.35 +/- 0.21 GeV/c(2). This result is the best measured weak mixing angle in all nu-N scattering experiments to date. We also present the improvements in the measurement from the new experiment, the NuTeV, hose expected M-w uncertainty is 110MeV/c(2). This expectation is compatible to the combined direct measurements from the Tevatron collider experiments. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Yu, JH (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 645 EP 648 PG 4 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100102 ER PT B AU Ribon, A AF Ribon, A BE Lellouch, D Mikenberg, G Rabinovici, E TI Measurement of time-dependent (B-0)over-bar-(B-10)over-bar flavor oscillation at CDF SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM AB The time dependence of B-0-(B) over bar(0) oscillations has been studied using several techniques by the CDF experiment at Fermilab. The data comprise 110 pb(-1) of collisions at root s = 1.8 TeV. Preliminary measurements of the B-0-(B) over bar(0) oscillation frequency (Delta m(d)) will be presented. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ribon, A (reprint author), Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 769 EP 770 PG 2 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100132 ER PT B AU Daoudi, M AF Daoudi, M BE Lellouch, D Mikenberg, G Rabinovici, E TI Search for CP-violation and b -> sg in inclusive B decays SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM AB We present preliminary results on two analyses performed by the SLD Collaboration using inclusive B decays: a search for CP violation and a search for the b --> sg transition. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Daoudi, M (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 775 EP 776 PG 2 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100135 ER PT B AU Frank, JS AF Frank, JS CA E787 Collaboration BE Lellouch, D Mikenberg, G Rabinovici, E TI Evidence for K+ -> pi(+)nu(nu)over-bar from E787 SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM ID SEARCH AB A collaboration from KEK, INS, Osaka, TRIUMF, Princeton, and BNL is currently running E787 at the AGS. The experiment is designed primarily to search for the rare decay K+ --> pi(+)nu<(nu)over bar>, with an expected branching ratio of similar to 10(-10) We report evidence that we have observed this decay. We also discuss the future outlook for the experiment. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Frank, JS (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 788 EP 789 PG 2 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100139 ER PT B AU Womersley, J AF Womersley, J BE Lellouch, D Mikenberg, G Rabinovici, E TI Searches for new particles in photon final states at the tevatron SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM ID ENERGY AB Searches for new physics at the Tevatron collider experiments, using signatures involving photons, are described. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Womersley, J (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 947 EP 950 PG 4 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100176 ER PT B AU Blum, T Soni, A AF Blum, T Soni, A BE Lellouch, D Mikenberg, G Rabinovici, E TI Update on lattice QCD with domain wall quarks SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM ID CHIRAL FERMIONS; MATRIX AB Using domain wall fermions, we estimate B-K(mu approximate to 2 GeV) = 0.602(38) in quenched QCD which is consistent with previous calculations. We also find ratios of decay constants that are consistent with experiment, within our statistical errors. Our initial results indicate good scaling behavior and support expectations that O(a) errors are exponentially suppressed in low energy (E << a(-1)) observables. It is also shown that the axial current numerically satisfies the lattice analog of the usual continuum axial Ward identity and that the matrix element of the four quark operator needed for BK exhibits excellent chiral behavior. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Brookhaven Natl Lab, Upton, NY 11973 USA. EM tblum@bnl.gov; soni@bnl.gov NR 15 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 1034 EP 1038 PG 5 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100194 ER PT B AU Paige, FE AF Paige, FE BE Lellouch, D Mikenberg, G Rabinovici, E TI Search for SUSY at LHC: Precision measurements SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM AB Methods to make precision measurements of SUSY masses and parameters at the CERN Large Hadron Collider are described. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Paige, FE (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 1171 EP 1176 PG 6 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100225 ER PT B AU Butler, JN AF Butler, JN BE Lellouch, D Mikenberg, G Rabinovici, E TI B physics at the tevatron: Now, soon, and later SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM AB We discuss recent B physics results obtained at the Fermilab Tevatron by CDF, prospects for observing CP violation in the next run, and a proposal for a Dedicated B Collider Experiment, BTeV, at the Tevatron after the next collider run. The main points of this paper are: The next round of experiments will certainly establish evidence for CP violation in B decays. The Tevatron Collider experiments can play a key role in this effort; Because of the limited statistics of this first round of CP experiments and with the growing appreciation of the theoretical difficulties of interpreting the results, this round will open up the study of CP violation in B decays but is not likely to close it out; and Hadron collider B experiments will play an even larger role in the second generation of "precision" CP violation and mixing studies because of the large number of B's they produce. Experiments with forward rapidity coverage may have the best chance of achieving the high efficiency required for this effort. Below, we discuss what has to be measured and with what accuracy; the reach of the next round of experiments - BaBar, Belie, CLEO, and HERA-B; CDF's prospects for their next run; and a new proposed experiment for Fermilab, BTeV. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Butler, JN (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 1200 EP 1207 PG 8 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100231 ER PT B AU Klima, B AF Klima, B CA DO Collaboration BE Lellouch, D Mikenberg, G Rabinovici, E TI Searches for pair production of first generation leptoquark at DO SO INTERNATIONAL EUROPHYSICS CONFERENCE ON HIGH ENERGY PHYSICS LA English DT Proceedings Paper CT International Europhysics Conference on High Energy Physics CY AUG 19-25, 1997 CL HEBREW UNIV JERUSALEM, JERUSALEM, ISRAEL SP Hebrew Univ Jerusalem, Tel Aviv Univ, European Union, DG XII, City Jerusalem, Israeli Minist Foreign Affairs, Goldschleger Conf Fdn, Weizmann Inst Sci, Israeli Acad Sci, Jerusalem Fund, Israeli Minist Sci, Einstein Ctr Theoret Phys, Israeli HEP Comm, N Cummings Chair Particle Phys, Technion Israel Inst Technol HO HEBREW UNIV JERUSALEM ID SCALAR LEPTOQUARKS; P(P)OVER-BAR COLLISIONS; DECAYS; DETECTOR AB We have searched for the pair production of first generation scalar leptoquarks using the full data set (123 pb(-1)) collected with the DO detector at the Fermilab Tevatron during 1992-1996. We observe no candidates, consistent with the expected background. We combine these new results from the ee + jets and e nu + jets channels with the published nu nu + jets result to obtain a 95% CL upper limits on the LQ pair production cross section as a function of mass and beta, the branching ratio to a charged lepton and a quark. Comparing to the NLO theory predictions, we set 95% CL lower limits on the LQ mass of 225, 204, and 79 GeV/c(2) for beta = 1, 1/2, and 0, respectively. The results of this analysis rule out an interpretation of the excess of high Q(2) events at HERA as leptoquarks with La mass below 200 GeV/c(2) for values of beta > 0.4. C1 Fermilab, Batavia, IL 60510 USA. RP Klima, B (reprint author), Fermilab, Batavia, IL 60510 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-64970-0 PY 1999 BP 1235 EP 1240 PG 6 WC Physics, Particles & Fields SC Physics GA BP59F UT WOS:000085594100236 ER PT J AU Chen, EP AF Chen, EP TI Non-local effects on dynamic damage accumulation in brittle solids SO INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS LA English DT Article DE damage; nonlocal; dynamic; continuum; numerical; brittle solid ID PLASTICITY; FRACTURE; STRAIN AB This paper presents a non-local analysis of the dynamic damage accumulation processes in brittle solids. A non-local formulation of a microcrack-based continuum damage model is developed and implemented into a transient dynamic finite element computer code. The code is then applied to the study of the damage accumulation process in a concrete plate with a central hole and subjected to the action of a step tensile pulse applied at opposite edges of the plate. Several finite element discretizations are used to examine the mesh size effect. Comparisons between calculated results based on local and non-local formulations are made and non-local effects are discussed. Copyright (C) 1999 John Wiley & Sons, Ltd. C1 Sandia Natl Labs, Struct & Thermomech Modeling Dept, Livermore, CA 94551 USA. RP Chen, EP (reprint author), Sandia Natl Labs, Struct & Thermomech Modeling Dept, Livermore, CA 94551 USA. NR 25 TC 44 Z9 47 U1 0 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0363-9061 J9 INT J NUMER ANAL MET JI Int. J. Numer. Anal. Methods Geomech. PD JAN PY 1999 VL 23 IS 1 BP 1 EP 21 DI 10.1002/(SICI)1096-9853(199901)23:1<1::AID-NAG892>3.0.CO;2-R PG 21 WC Engineering, Geological; Materials Science, Multidisciplinary; Mechanics SC Engineering; Materials Science; Mechanics GA 157DP UT WOS:000078045000001 ER PT J AU Shadid, JN AF Shadid, JN TI A fully-coupled Newton-Krylov solution method for parallel unstructured finite element fluid flow, heat and mass transfer simulations SO INTERNATIONAL JOURNAL OF COMPUTATIONAL FLUID DYNAMICS LA English DT Article DE iterative solvers; FEM; parallel CFD; unstructured grids ID NAVIER-STOKES EQUATIONS; FORMULATION AB This manuscript briefly describes a robust iterative solution methodology used for parallel unstructured finite element simulation of strongly coupled fluid flow, heat and mass transfer. The solution method relies on an inexact Newton scheme and linear system solvers based on preconditioned Krylov subspace methods. The discussion considers computational efficiency and robustness issues related to the proposed schemes. The evaluated preconditioning techniques include simple polynomial expansion and multi-step block iterative methods along with overlapping Schwarz domain decomposition techniques using subdomain solvers based on incomplete factorizations. For this comparison a particular spatial discretization of the governing transport PDEs based on a Galerkin Least Squares (GLS) finite element formulation is used. Results are presented for some standard 2D CFD benchmark problems as well as for a number of 3D problems. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Shadid, JN (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 23 TC 21 Z9 21 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1061-8562 J9 INT J COMPUT FLUID D JI Int. J. Comput. Fluid Dyn. PY 1999 VL 12 IS 3-4 BP 199 EP + DI 10.1080/10618569908940825 PG 14 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 256NU UT WOS:000083732300002 ER PT J AU Atwood, T AF Atwood, T TI The role of coal technologies to support responsible economic growth SO INTERNATIONAL JOURNAL OF ENVIRONMENT AND POLLUTION LA English DT Article DE Asian Pacific economies; clean coal technology; debt financing AB The Asian Pacific region is home to the fastest-growing economies in the world. These economies are expected to double gross domestic product (GDP) in the next decade, and coal will play a major role as the primary energy source for electric power. The tremendous projected financial burden associated with the installation of new, coal-fired electric power facilities to fuel this unprecedented economic growth has focused efforts to identify existing and new sources of financing for major thermal power projects that are efficient and environmentally responsible. The economics are trying to accelerate economic development and promote the leveraging of in-country resources to meet their electric power objectives. With the growth in power production will come more greenhouse gas emissions and negative environmental impacts. The means to reducing these impacts is clean coal technology, which is becoming more and more accepted for debt financing. Competition for debt financing is becoming tighter worldwide, with increased use of project financing. Representatives of the coal technology and equipment industries believe that the availability of non-recourse financing is an impediment to greater penetration of clean coal technology into electric power markets in Asian Pacific economies. Better use of existing infrastructure project financing instruments and management of risk in Asian markets are critical to the development and acceptance of clean coal technology to meet greenhouse gas abatement and economic goals. C1 US Dept Energy, Fossil Energy Off Coal & Power Syst, Germantown, MD 20874 USA. RP Atwood, T (reprint author), US Dept Energy, Fossil Energy Off Coal & Power Syst, Germantown, MD 20874 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU INDERSCIENCE ENTERPRISES LTD PI GENEVA AEROPORT PA WORLD TRADE CENTER BLDG 110 AVE LOUSIS CASAI CP 306, CH-1215 GENEVA AEROPORT, SWITZERLAND SN 0957-4352 J9 INT J ENVIRON POLLUT JI Int. J. Environ. Pollut. PY 1999 VL 12 IS 1 BP 14 EP 33 DI 10.1504/IJEP.1999.002278 PG 20 WC Environmental Sciences SC Environmental Sciences & Ecology GA 279EB UT WOS:000085030500003 ER PT J AU Ritchie, RO AF Ritchie, RO TI Mechanisms of fatigue-crack propagation in ductile and brittle solids SO INTERNATIONAL JOURNAL OF FRACTURE LA English DT Article DE fatigue-crack propagation; crack-tip shielding; metals; ceramics; intermetallics; intrinsic and extrinsic mechanisms ID INTERMETALLIC MATRIX COMPOSITES; CYCLIC FATIGUE; FRACTURE-TOUGHNESS; GROWTH-BEHAVIOR; MOLYBDENUM DISILICIDE; STABILIZED ZIRCONIA; SILICON-CARBIDE; CERAMICS; RESISTANCE; ALUMINA AB The mechanisms of fatigue-crack propagation are examined with particular emphasis on the similarities and differences between cyclic crack growth in ductile materials, such as metals, and corresponding behavior in brittle materials, such as intermetallics and ceramics. This is achieved by considering the process of fatigue-crack growth as a mutual competition between intrinsic mechanisms of crack advance ahead of the crack tip (e.g., alternating crack-tip blunting and resharpening), which promote crack growth, and extrinsic mechanisms of crack-tip shielding behind the tip (e.g., crack closure and bridging), which impede it. The widely differing nature of these mechanisms in ductile and brittle materials and their specific dependence upon the alternating and maximum driving forces (e.g., Delta K and K-max) provide a useful distinction of the process of fatigue-crack propagation in different classes of materials; moreover, it provides a rationalization for the effect of such factors as load ratio and crack size. Finally, the differing susceptibility of ductile and brittle materials to cyclic degradation has broad implications for their potential structural application; this is briefly discussed with reference to lifetime prediction. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RP Ritchie, RO (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Ritchie, Robert/A-8066-2008 OI Ritchie, Robert/0000-0002-0501-6998 NR 69 TC 308 Z9 311 U1 8 U2 108 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0376-9429 J9 INT J FRACTURE JI Int. J. Fract. PY 1999 VL 100 IS 1 BP 55 EP 83 DI 10.1023/A:1018655917051 PG 29 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA 288PM UT WOS:000085572300003 ER PT J AU Helms, KLE Allen, DH Hurtado, LD AF Helms, KLE Allen, DH Hurtado, LD TI A model for predicting grain boundary cracking in polycrystalline viscoplastic materials including scale effects SO INTERNATIONAL JOURNAL OF FRACTURE LA English DT Article DE polycrystalline solids; viscoplasticity; damage; cohesive zone; crack propagation; grain boundary fracture; titanium; Timetal-21S; scale effects ID METAL CERAMIC COMPOSITES; WHISKER-REINFORCED METAL; VOID NUCLEATION; DEFORMATION; DECOHESION; INTERFACE; FRACTURE AB A model is developed herein for predicting the mechanical response of inelastic crystalline solids. Particular emphasis is given to the development of microstructural damage along grain boundaries, and the interaction of this damage with intragranular inelasticity caused by dislocation dissipation mechanisms. The model is developed within the concepts of continuum mechanics, with special emphasis on the development of internal boundaries in the continuum by utilizing a cohesive zone model based on fracture mechanics. In addition, the crystalline grains are assumed to be characterized by nonlinear viscoplastic mechanical material behavior in order to account for dislocation generation and migration. Due to the nonlinearities introduced by the crack growth and viscoplastic constitution, a numerical algorithm is utilized to solve representative problems. Implementation of the model to a finite element computational algorithm is therefore briefly described. Finally, sample calculations are presented for a polycrystalline titanium alloy with particular focus on effects of scale on the predicted response. C1 Texas A&M Univ, Dept Aerosp Engn, College Stn, TX 77843 USA. Sandia Natl Labs, Albuquerque, NM 88101 USA. RP Helms, KLE (reprint author), Texas A&M Univ, Dept Aerosp Engn, College Stn, TX 77843 USA. NR 37 TC 19 Z9 19 U1 0 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0376-9429 J9 INT J FRACTURE JI Int. J. Fract. PY 1999 VL 95 IS 1-4 BP 175 EP 194 DI 10.1023/A:1018696101352 PG 20 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA 237VJ UT WOS:000082677000011 ER PT J AU Rocha, LM AF Rocha, LM TI Evidence sets: Modeling subjective categories SO INTERNATIONAL JOURNAL OF GENERAL SYSTEMS LA English DT Article DE fuzzy sets; Dempster-Shafer theory of evidence; interval valued fuzzy sets; uncertainty; cognitive categorization; constructivism; relational databases; information technology; information retrieval; adaptive collaborative; systems knowledge management ID VALUED FUZZY-SETS; INTERVAL; UNCERTAINTY; FUZZINESS; NEGATION AB Zadeh's Fuzzy Sets are extended with the Dempster-Shafer Theory of Evidence into a new mathematical structure called Evidence Sets, which can capture more efficiently all recognized forms of uncertainty in a formalism that explicitly models the subjective context dependencies of linguistic categories. A belief-based theory of Approximate Reasoning is proposed for these structures. Evidence sets are then used in the development of a relational database architecture useful for the data mining of information stored in several networked databases. This useful data mining application establishes an Artificial Intelligence model of Cognitive Categorization with a hybrid architecture that possesses both connectionist and symbolic attributes. C1 Los Alamos Natl Lab, Complex Syst Modeling Team, Comp Res Grp CIC3, Los Alamos, NM 87545 USA. RP Rocha, LM (reprint author), Los Alamos Natl Lab, Complex Syst Modeling Team, Comp Res Grp CIC3, MS P990 Los Alamos, Los Alamos, NM 87545 USA. EM rocha@lanl.gov OI Rocha, Luis/0000-0001-9402-887X NR 38 TC 8 Z9 8 U1 2 U2 2 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0308-1079 J9 INT J GEN SYST JI Int. J. Gen. Syst. PY 1999 VL 27 IS 6 BP 457 EP 494 DI 10.1080/03081079908962089 PG 38 WC Computer Science, Theory & Methods; Ergonomics SC Computer Science; Engineering GA 225HD UT WOS:000081951600002 ER PT J AU Lee, WH Painter, JW AF Lee, WH Painter, JW TI Material void-opening computation using particle method SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article DE material void space; particle method AB When performing two-dimensional Eulerian calculations of material flow, one always encounters difficulties in modeling void opening due to material failure, such as fracture, spallation, or phase change. The present studies use one type of particle to represent the material and another type to represent the void space. According to the flow conditions, the void space may grow with crack propagation, or the neighboring, nonvoid material may recombine when the void space closes up. The penetration of a tungsten rod into an aluminum block, the penetration of a copper rod into a steel plate, the necking of a shaped-charge jet, the formation of a self-forging fragment, and two shaped charges with tungsten-copper liners are calculated using the present code. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Lee, WH (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 8 TC 5 Z9 8 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD JAN PY 1999 VL 22 IS 1 BP 1 EP 22 DI 10.1016/S0734-743X(98)00041-4 PG 22 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 174MU UT WOS:000079039600001 ER PT J AU Brigmon, RL Anderson, TA Fliermans, CB AF Brigmon, R. L. Anderson, T. A. Fliermans, C. B. TI Methanotrophic Bacteria in the Rhizosphere of Trichloroethylene-Degrading Plants SO INTERNATIONAL JOURNAL OF PHYTOREMEDIATION LA English DT Article DE methanotrophic bacteria; trichloroethylene; rhizosphere soils AB The presence and density of methanotrophic bacteria has been shown to play an important role in the bioremediation of trichloroethylene (TCE). This article describes the methanotrophic bacterial densities in rhizosphere soils from two areas of the Department of Energy's Savannah River Site in Aiken, South Carolina. A direct fluorescent antibody (DFA) technique was evaluated to determine the presence of methanotrophic bacteria in roots and rhizospheres from vascular plants. The first site, the Miscellaneous Chemical Basin (MCB), was contaminated with a mixture of chemicals, including chlorinated solvents. The second site will be potentially affected by outcropping of TCE-contaminated groundwater. Significantly higher numbers of methanotrophic bacteria were observed with DFA in rhizosphere soils and on roots of Lespedeza cuneata and Pinus taeda (that previously showed higher rates of C-14-TCE mineralization) compared with nonvegetated soils. In addition, viable and heterotrophic microbial counts were consistently higher in rhizosphere soils and on plant roots compared with nonvegetated soils. Therefore, the presence of these plant species may enhance C-14-TCE mineralization by selectively increasing the microbial population in the root zone. Methanotrophic bacteria were directly observed by DFA in soils, on the surface of root hairs, within plant roots, and in higher densities associated with mycorrhizal fungi. These experiments provide further evidence that specific types of bacterial interactions with vegetation in the rhizosphere may play an important role in remediation of TCE-contaminated soils and groundwater. C1 [Brigmon, R. L.; Fliermans, C. B.] Westinghouse Savannah River Co, Savannah River Technol Ctr, Environm Biotechnol Sect, Aiken, SC 29808 USA. [Anderson, T. A.] Texas Tech Univ, Inst Environm & Human Hlth, Lubbock, TX 79416 USA. RP Brigmon, RL (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Environm Biotechnol Sect, Bldg 704-8T TNX, Aiken, SC 29808 USA. EM R03.brigmon@srs.gov FU U.S. Department of Energy (DOE) [DE-AC09-76SR00001]; U.S. DOE FX This article was prepared in connection with work done under a subcontract to Contract No. DE-AC09-76SR00001 with the U.S. Department of Energy (DOE). RLB was supported in part by an appointment to the U. S. DOE Laboratory Cooperative Postgraduate Research Training Program at the Savannah River Site administered by the Oak Ridge Institute for Science and Education (ORISE). TAA was supported in part by the U.S. DOE Faculty Research Travel Program administered by ORISE. We appreciate the helpful contributions to this study of T. C. Hazen, D. P. Shupack, R. White, and M. M. Franck. NR 34 TC 11 Z9 12 U1 1 U2 2 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 530 CHESTNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA SN 1522-6514 EI 1549-7879 J9 INT J PHYTOREMEDIAT JI Int. J. Phytoremediat. PY 1999 VL 1 IS 3 BP 241 EP 253 DI 10.1080/15226519908500018 PG 13 WC Environmental Sciences SC Environmental Sciences & Ecology GA V33JL UT WOS:000209015000003 ER PT J AU Punshon, T Dickinson, N AF Punshon, Tracy Dickinson, Nicholas TI Heavy Metal Resistance and Accumulation Characteristics in Willows SO INTERNATIONAL JOURNAL OF PHYTOREMEDIATION LA English DT Article DE Salix; trees; heavy metals; phytoremediation AB The resistance of Salix to Cu, Cd, Ni, and Zn was investigated in hydroponic culture, with phytoextraction potential evaluated for Cu. Root elongation (indicative of resistance level) was significantly affected, with considerable variation between and within individual clones. Resistance appeared to be clone- or hybrid-specific, rather than species-specific. S. caprea clones (and hybrids) were among the most resistant, but a secondary S. caprea clone from a different provenance was much less tolerant. S. viminalis and S. triandra clones were the most sensitive. Highest resistance was found in response to Cd, while Cu and Ni were extremely toxic. A resistant S. caprea ecotype originating from a metalliferous mine spoil was identified using this technique. Copper concentration reached a maximum of 2000, 400, and 82 m g g(-1) (d.wt) in roots, wood, and foliage, respectively, after 1 month in hydroponic culture. The level of variation in the response of Salix to metals may cause difficulties in phytoremediation screening programs, but may be essential in providing genetic variation for selection of metal resistance traits, where the contaminant profile is heterogeneous, mixed, or subject to change. Clone selection for metal phytoextraction is feasible, but a longer field-scale study on metal-contaminated soils is needed before their role in phytoremediation can be confirmed. C1 [Punshon, Tracy; Dickinson, Nicholas] Liverpool John Moores Univ, Sch Biol & Earth Sci, Liverpool L3 3AF, Merseyside, England. RP Punshon, T (reprint author), Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. EM punshon@srel.edu; besndick@livjm.ac.uk NR 39 TC 39 Z9 43 U1 2 U2 5 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 530 CHESTNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA SN 1522-6514 EI 1549-7879 J9 INT J PHYTOREMEDIAT JI Int. J. Phytoremediat. PY 1999 VL 1 IS 4 BP 361 EP 385 DI 10.1080/15226519908500025 PG 25 WC Environmental Sciences SC Environmental Sciences & Ecology GA V33JS UT WOS:000209015700004 ER PT J AU Miller, MP Harley, EJ Bammann, DJ AF Miller, MP Harley, EJ Bammann, DJ TI Reverse yield experiments and internal variable evolution in polycrystalline metals SO INTERNATIONAL JOURNAL OF PLASTICITY LA English DT Article DE constitutive behavior; polycrystalline materials; metallic materials; viscoplastic materials; mechanical testing ID FCC METALS; PLASTIC RELAXATION; COPPER-SILICA; STRAIN-RATE; DEFORMATION; STRESS; MODEL; BEHAVIOR; ALUMINUM; FLOW AB In this work, sequences of reverse yield experiments are used to measure the evolution of the directionally-dependent contribution to strain-hardening in OFHC copper. It is shown that based upon a 50 microstrain offset definition of yielding, a strength asymmetry commonly known as the Bauschinger effect develops and increases with prestrain. From the perspective of macroscale isotropic/kinematic hardening models, these data imply an increase in the kinematic hardening component of the yield strength. Hardening model parameters are determined by integrating the evolution equations and correlating the experimental data. Consistency between these modeling results and other data on the same heat of OFHC copper is then explored. It is found that while the reverse yield tests show the kinematic hardening variable, a, increasing in magnitude for uniaxial strains up to 20%, the tensor must very quickly change direction in stress space when the straining path is altered. Stress relaxation experiments were conducted and strain rate effects including the decomposition of the rate dependence between the flow rule and the evolution equations are investigated. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Cornell Univ, Sibley Sch Mech & Aerosp Engn, Ithaca, NY 14853 USA. Sandia Natl Labs, Ctr Mat & Mech, Livermore, CA 94551 USA. RP Miller, MP (reprint author), Cornell Univ, Sibley Sch Mech & Aerosp Engn, Ithaca, NY 14853 USA. NR 47 TC 11 Z9 12 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0749-6419 J9 INT J PLASTICITY JI Int. J. Plast. PY 1999 VL 15 IS 1 BP 93 EP 117 DI 10.1016/S0749-6419(98)00046-1 PG 25 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Mechanics SC Engineering; Materials Science; Mechanics GA 180PD UT WOS:000079393600004 ER PT J AU Maudlin, PJ Bingert, JF House, JW Chen, SR AF Maudlin, PJ Bingert, JF House, JW Chen, SR TI On the modeling of the Taylor cylinder impact test for orthotropic textured materials: experiments and simulations SO INTERNATIONAL JOURNAL OF PLASTICITY LA English DT Article ID MULTISURFACE PLASTICITY; YIELD SURFACE; TANTALUM; DEFORMATION; BEHAVIOR AB Taylor impact tests using specimens cut from a rolled plate of tantalum were conducted. The tantalum was experimentally characterized in terms of flow stress and crystallographic texture. A piece-wise yield surface was interrogated from an ODF corresponding to this texture assuming two slip system modes, in conjunction with an elastic stiffness tensor computed from the same ODF and single crystal elastic properties. This constitutive information was used in EPIC-95 3D simulations of a Taylor impact test, and good agreement was realized between the calculational results and the experimental post-test geometries in terms of major and minor side profiles and impact-interface footprints. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 USA. RP Maudlin, PJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 29 TC 56 Z9 56 U1 0 U2 13 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0749-6419 J9 INT J PLASTICITY JI Int. J. Plast. PY 1999 VL 15 IS 2 BP 139 EP 166 DI 10.1016/S0749-6419(98)00058-8 PG 28 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Mechanics SC Engineering; Materials Science; Mechanics GA 184EM UT WOS:000079597500002 ER PT J AU Park, JJ AF Park, JJ TI Creep behavior of W-4Re-0.32HfC and its comparison with some creep models SO INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS LA English DT Article DE tungsten-rhenium-hafnium carbide; creep; Ansell-Weertman model; Lagneborg model; Roesler-Arzt model AB The high-temperature creep behavior of tungsten-4 wt% rhenium-0.32 wt% hafnium carbide (W-4Re-0.32HfC) was evaluated at temperatures ranging from 2200 to 2400 K and stresses ranging from 40 to 70 MPa in a vacuum less than 1.33 x 10(-6) Pa (1.0 x 10(-8) torr). The effects of temperature and stress on the secondary creep rate were determined. The stress exponent for creep was 5.2, and the activation energy for creep was 594 kJ/mol. These creep parameters were compared with predictions made by three creep models: the Ansell-Weertman, Lagneborg and Roesler-Arzt models. The results showed that none of these models accurately predicted the creep behavior of the alloy. However, the Lagneborg recovery creep model qualitatively predicted the secondary creep rate of W4Re-0.32HfC. The stress exponent for creep that was predicted by the Ansell-Weertman model did not agree with the values obtained in this research. The secondary creep rate that was predicted by the Roesler-Arzt model was approximately five orders of magnitude different from the rate obtained in this research. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Park, JJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS E508, Los Alamos, NM 87545 USA. NR 11 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0263-4368 J9 INT J REFRACT MET H JI Int. J. Refract. Met. Hard Mat. PY 1999 VL 17 IS 5 BP 331 EP 337 DI 10.1016/S0263-4368(99)00023-2 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 267AT UT WOS:000084333000001 ER PT J AU Fink, JK Sofu, T Ley, H AF Fink, JK Sofu, T Ley, H TI International Nuclear Safety Center database on thermophysical properties of reactor materials SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article; Proceedings Paper CT 13th Symposium on Thermophysical Properties CY JUN 22-27, 1997 CL UNIV COLORADO, BOULDER, COLORADO SP Amer Soc Mech Engineers, Heat Transfer Div, Standing Comm Thermophys Properties, Natl Inst Stand & Technol, Chem Sci & Technol Lab, Phys & Chem Properties Div HO UNIV COLORADO DE database; fuel; cladding; material properties; reactor materials; thermodynamic properties; transport properties ID THERMAL-CONDUCTIVITY; ZIRCONIUM AB The International Nuclear Safety Center (INSC) database has been established at Argonne National Laboratory to provide easily accessible data and information necessary to perform nuclear safety analyses and to promote international collaboration through the exchange of nuclear safety information. The INSC database, located on the World Wide Web at http://www.insc.anl.gov, contains critically assessed recommendations for reactor-material properties for normal operating conditions, transients, and severe accidents. The initial focus of the database is on thermodynamic and transport proper ties of materials for water reactors. Materials that are being included in the database are fuel, absorbers, cladding, structural materials, coolants, and liquid mixtures of combinations of UO2, ZrO2, Zr, stainless steel, absorber materials, and concrete. For each property, the database includes (1) a summary of recommended equations with uncertainties; (2) a detailed data assessment giving the basis for the recommendations, comparisons with experimental data and previous recommendations, and uncertainties; (3) graphs showing recommendations, uncertainties, and comparisons with data and other equations; and (4) property values tabulated as a function of temperature. C1 Argonne Natl Lab, Reactor Engn Div, Argonne, IL 60439 USA. Argonne Natl Lab, Reactor Anal Div, Argonne, IL 60439 USA. RP Fink, JK (reprint author), Argonne Natl Lab, Reactor Engn Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 14 TC 1 Z9 1 U1 0 U2 3 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD JAN PY 1999 VL 20 IS 1 BP 279 EP 287 DI 10.1023/A:1021463121533 PG 9 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA 181PJ UT WOS:000079450600026 ER PT J AU Nieh, TG Wadsworth, J AF Nieh, TG Wadsworth, J TI Fine structure superplastic intermetallics SO INTERNATIONAL MATERIALS REVIEWS LA English DT Review ID HIGH-STRAIN RATES; HIGH-TEMPERATURE DEFORMATION; SEVERE PLASTIC-DEFORMATION; ELEVATED-TEMPERATURE; MECHANICAL-BEHAVIOR; MICROSTRUCTURE EVOLUTION; TITANIUM ALUMINIDES; NI3(SI,TI) ALLOYS; GRAIN-BOUNDARIES; NICKEL SILICIDE AB Recent advances in the basic understanding of fi ne structure superplasticity and the superplastic forming of intermetallics are reviewed. Superplastic characteristics in the nickel base (e.g. Ni3Al and Ni3Si), titanium base (e.g. Ti3Al and TiAl), and iron base (e.g. Fe3Al, FeAl, and Fe3Si) intermetallics are individually described. Deformation mechanisms are addressed as well as microstructural requirements and effects such as grain size, second phases and their distributions, and grain boundary structures. Two of the most interesting recent observations are also included for discussion: one is the observation of low temperature superplasticity in TiAl, and the other is coarse grained superplasticity in Fe3Al and FeAl. In addition, several examples of superplastic forming, including isothermal forging and biaxial gas-pressure forming, of several intermetallics are presented with comments on the likelihood of commercial application. Comparisons are made on the differences among superplastic behaviour in metals, ceramics, and intermetallics. IMR/339 (C) 1999 IoM Communications Ltd and ASM International. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Lawrence Livermore Natl Lab, L-350,POB 808, Livermore, CA 94551 USA. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 153 TC 38 Z9 44 U1 2 U2 20 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND SN 0950-6608 EI 1743-2804 J9 INT MATER REV JI Int. Mater. Rev. PY 1999 VL 44 IS 2 BP 59 EP 75 PG 17 WC Materials Science, Multidisciplinary SC Materials Science GA 244AB UT WOS:000083028700002 ER PT B AU Chanchani, R AF Chanchani, R GP IEEE IEEE TI Modeling and simulation - The effects of grain coarsening on local stresses and strains in solder microstructure SO INTERNATIONAL SYMPOSIUM ON ADVANCED PACKAGING MATERIALS: PROCESSES, PROPERTIES AND INTERFACES, PROCEEDINGS LA English DT Proceedings Paper CT International Symposium on Advanced Packaging Materials - Processes, Properties and Interfaces CY MAR 14-17, 1999 CL BRASELTON, GA SP Int Microelectr & Packaging Soc AB A critical issue in the long-term reliability of solder connections used in electronic packages is the joint failure during thermal cycling. Presently in most finite element analysis to predict the solder joint fatigue failures, solder is assumed as a homogeneous single-phase metal. However in the last decade, several metallurgical studies have shown that solder microstructure may have a role in early solder joint failures (ref 1). Investigators have observed (ref 1) that solder microstructure coarsens in local bands during aging and during thermal cycle fatigue. In a failed solder joint, the fatigue cracks are found in these bands of coarse grains. It is speculated that the grain coarsening increases the local strains within the microstructure, thereby increasing the likelihood for a crack to initiate. The objective of this study is to model and simulate the effect of grain coarsening on local stresses and strains. During solidification of eutectic Pb/Sn solder, two types of microstructures form, namely lamellar and equiaxed. In this study, I have developed a computer code to generate both types of microstructures of varying grain coarseness. This code is incorporated into the finite element (FE) code that analyzes the local stresses and strains within the computer-generated microstructure. The FE code, specifically developed for this study, uses an algorithm involving the sparse matrix and iterative solver. This code on a typical single-processor machine will allow the analyst to use over I million degrees of freedom. For higher number of degrees of freedom, we have also developed a code to run on a parallel machine using message passing interface. The data reported in this paper were obtained using the single-processor code. The solder microstructure, if assumed to be homogeneous single phase, has gradual variation in local stresses and strains. In 2-phase solder, von mises stresses and strains are heterogeneously distributed. In general, the maximum von mises stress in 2-phase solder case are higher than in 1-phase solder. In lamellar microstructure of 2-phase solder, the maximum von mises stress in the microstructure gradually increases with grain coarseness. In equiaxed microstructure of 2-phase solder, the maximum von mises stress does not follow a general trend, increasing or decreasing, with increasing grain coarseness. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Chanchani, R (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 5 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-930815-56-4 PY 1999 BP 136 EP 143 DI 10.1109/ISAPM.1999.757301 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BM70H UT WOS:000079533800025 ER PT B AU Dimos, D King, BH Yang, P AF Dimos, D King, BH Yang, P GP IEEE IEEE TI Direct-write fabrication of integrated, multilayer passive components SO INTERNATIONAL SYMPOSIUM ON ADVANCED PACKAGING MATERIALS: PROCESSES, PROPERTIES AND INTERFACES, PROCEEDINGS LA English DT Proceedings Paper CT International Symposium on Advanced Packaging Materials - Processes, Properties and Interfaces CY MAR 14-17, 1999 CL BRASELTON, GA SP Int Microelectr & Packaging Soc AB The need for advanced (electronic) components and packages with smaller size, greater functionality, and enhanced reliability requires the ability to integrate electronic ceramics in complex 3-D architectures. However, traditional tape casting and screen printing approaches are poorly suited to the requirements of rapid prototyping and small-lot manufacturing. To address this need, we are developing a direct-write approach for fabricating highly integrated, multilayer components using a micropen to deposit slurries in precise patterns. This approach provides the ability to fabricate multifunctional, multimaterial integrated ceramic components (MMICCs) in an agile and rapid way. Commercial ceramic and metal thick films can be used directly in the system, as can filled polymer thick-film pastes. With this system, we have made custom resistor networks, integrated RC filters, flat inductors, and multiturn voltage transformers. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Dimos, D (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM dbdimos@sandia.gov NR 10 TC 6 Z9 6 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-930815-56-4 PY 1999 BP 186 EP 190 DI 10.1109/ISAPM.1999.757309 PG 3 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BM70H UT WOS:000079533800033 ER PT B AU Minniti, D AF Minniti, D CA MACHO Collaboration BE Impey, C TI Variable stars in the MACHO bulge database SO INTERNATIONAL SYMPOSIUM ON ASTROPHYSICS RESEARCH AND SCIENCE EDUCATION LA English DT Proceedings Paper CT International Symposium on Astrophysics Research and Science Education CY JUN, 1998 CL VATICAN OBSERV, VATICAN CITY, VATICAN HO VATICAN OBSERV ID GALACTIC BULGE; GALAXY AB The MACHO Project has been monitoring large fields in the direction of the Galactic bulge, the LMC and SMC for over 6 years. These nightly observations taken in two passbands provide an unprecedented database for astronomers. This database, now reaching 5 Terabytes in size, has produced results relevant to microlensing, variable stars, galactic structure, and stellar evolution. An overview of the data is given, outlining some potential future applications. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Minniti, D (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU UNIV NOTRE DAME PRESS PI NOTRE DAME PA 310 FLANNER HALL, NOTRE DAME, IN 46556-5611 USA BN 0-268-03155-X PY 1999 BP 181 EP 185 PG 5 WC Astronomy & Astrophysics; Education, Scientific Disciplines SC Astronomy & Astrophysics; Education & Educational Research GA BQ97H UT WOS:000165195900038 ER PT S AU Thompson, VS Barrett, KB Davis, T Nieto, SR Unger, TF AF Thompson, VS Barrett, KB Davis, T Nieto, SR Unger, TF BE Higgins, K TI Antibody profiling as an identification tool for forensic samples SO INVESTIGATION AND FORENSIC SCIENCE TECHNOLOGIES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Meeting on Investigation and Forensic Science Technologies CY NOV 03-04, 1998 CL BOSTON, MA SP SPIE, Pacific NW Natl Lab DE antibody profiling; identification; antibody fingerprinting; forensic identification AB A novel identification technique called antibody profiling was examined as an alternative to DNA-based methods for matching crime scene evidence to a suspect. This technique provides results within 2 hours, is 1/100 the cost of DNA tests, and does not require skilled technicians or expensive equipment, A matrix of 422 blood samples were prepared to mimic typical crime scene conditions and provide validation for the technique. The effects of sample size, drying temperature, binary and ternary blood mixtures, adulteration with chemicals, and placement on a variety of surfaces were examined. Using the antibody profiling method, 91% of the 422 samples were correctly identified, in addition, binary blood mixtures could be identified with up to 40% contaminating blood. Temperatures at or above 60 degrees C and the presence of soil in the samples interfered with the ability to correctly identify samples. In this study, the antibody profiling technique was shown to be an excellent alternative to DNA-based identification methods. This method will find applications in situations where results are needed rapidly, where it is necessary to screen multiple suspects, and in remote areas where the equipment and technical skills needed for DNA testing are not available. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Thompson, VS (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. RI Thompson, Vicki/B-9086-2017 OI Thompson, Vicki/0000-0003-4975-392X NR 6 TC 0 Z9 0 U1 0 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3042-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3576 BP 52 EP 59 DI 10.1117/12.334545 PG 8 WC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology SC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology GA BM50A UT WOS:000078902000009 ER PT S AU Groenewold, GS Gresham, GL Gianotto, AK Avci, R AF Groenewold, GS Gresham, GL Gianotto, AK Avci, R BE Higgins, K TI Contaminant characterization on hair and fiber surfaces using imaging TOF-SIMS SO INVESTIGATION AND FORENSIC SCIENCE TECHNOLOGIES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Meeting on Investigation and Forensic Science Technologies CY NOV 03-04, 1998 CL BOSTON, MA SP SPIE, Pacific NW Natl Lab DE forensic science; drugs; organophosphates; surfactants; fibers; hair; secondary ion mass spectrometry ID ION MASS-SPECTROMETRY; STATIC SIMS; ENVIRONMENTAL SURFACES; TRIBUTYL-PHOSPHATE; MICROSCOPE AB Imaging time-of-flight secondary ion mass spectrometry (SIMS) was used to evaluate the detection of contaminant chemicals on the surfaces of single synthetic textile and canine hair fibers. The results of the study showed that a variety of chemical classes can be detected. Both cocaine and heroin could be easily observed as intact protonated molecules ([M + H](+)) in the cation spectra acquired from textile fibers. Two organophosphates were evaluated: malathion,which is a common pesticide, and pinacolyl methyl phosphonic acid (PMPA), which is the principal degradation product of the nerve agent soman (a close relative of sarin). Malathion could be observed as (CH3O)(2)P(=S)S-., which is formed by thiophosphate cleavage of the intact malathion. PMPA is observed as the conjugate base ([PA-IPA - H](.)). Surfactant chemicals found in hair care products were successfully detected on single hair fibers. Specifically, alkyl sulfates, ethoxylated alkyl sulfates, silicones, and alkylammonium compounds could be readily identified in spectra acquired from single hair fiber samples exposed to shampoo and/or conditioner. Generally, the results of the study show that imaging SIMS is applicable to single fiber analysis, for a range of adsorbed compound types. The forensic application of this instrumental approach has not been widely recognized. However, the ability of the technique to acquire specific chemical information from trace samples clearly points to applications where the need for chemical analysis is great, but the amount of sample is limited. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Groenewold, GS (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 11 TC 1 Z9 1 U1 1 U2 8 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3042-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3576 BP 60 EP 65 DI 10.1117/12.334515 PG 6 WC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology SC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology GA BM50A UT WOS:000078902000010 ER PT S AU Gresham, GL Groenewold, GS Bauer, WF Ingram, JC Avci, R AF Gresham, GL Groenewold, GS Bauer, WF Ingram, JC Avci, R BE Higgins, K TI Static secondary ion mass spectrometry characterization of nail polish and paint surfaces SO INVESTIGATION AND FORENSIC SCIENCE TECHNOLOGIES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Meeting on Investigation and Forensic Science Technologies CY NOV 03-04, 1998 CL BOSTON, MA SP SPIE, Pacific NW Natl Lab DE forensic science; paint; fingernail polish; static secondary ion mass spectrometry ID LEAST-SQUARES METHODS; IONIZATION; SIMS AB A variety of paint and fingernail polish samples, which were visually similar, but had different chemical compositions, were analyzed using three static secondary ion mass spectrometry (SIMS) techniques. These techniques included: 1) high spatial resolution / high mass resolution imaging time-of-flight SIMS; 2) analysis of stabilized high mass secondary ions with an ion trap SIMS capable of MS/MS; 3) qualitative characterization using a quadrupole SIMS with "pulsed extraction" charge compensation. In some cases, distinguishing between different coatings was easily achieved because of the presence of dominant ions derived from the components of the coating materials in the SIMS spectra. In other instances, coating distinction was difficult within a product group because of spectral complexity; for this reason, multivariate statistical techniques were employed, which allowed meaningful classification of spectra Partial Least Squares and Principle Component Analysis were applied to quadrupole SIMS data. When using Partial Least Squares analysis reasonably accurate coating identification was achieved with the preliminary data with overall correct identifications at greater than 90% sensitivity. C1 Idaho Nalt Engn & Environm Lab, Surface Res Grp, Idaho Falls, ID 83415 USA. RP Gresham, GL (reprint author), Idaho Nalt Engn & Environm Lab, Surface Res Grp, POB 1625, Idaho Falls, ID 83415 USA. RI Bauer, William/B-8357-2016 OI Bauer, William/0000-0002-7190-9700 NR 16 TC 1 Z9 1 U1 2 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3042-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3576 BP 66 EP 72 DI 10.1117/12.334516 PG 7 WC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology SC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology GA BM50A UT WOS:000078902000011 ER PT J AU Liu, J Weppner, W AF Liu, J. Weppner, W. TI Electronic Conductivity Measurement of Gadolinia Doped Ceria by DC-Partial-Polarization SO IONICS LA English DT Article AB A simple technique is presented to measure the partial electronic conductivity of solid electrolytes. It is based on the Hebb-Wagner polarization method but does not require complete blocking of the electrode. A major advantage of the method is the applicability over a much wider temperature range, especially measurements at higher temperatures. The technique needs to satisfy only the condition that the oxygen partial pressure in the reference gas is sufficiently low in order to decrease the ionic current to such an amount that the electronic conduction will be predominant at higher polarization voltages. The simple experimental arrangement is applied to measure the conductivity of the electronic minority charge carriers and to calculate the EDB (electrolytic domain boundary) values of 20 mol-% gadolinia doped ceria. C1 [Liu, J.; Weppner, W.] Univ Kiel, Fac Engn, D-24143 Kiel, Germany. RP Liu, J (reprint author), Argonne Natl Lab, CMT, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 5 TC 6 Z9 6 U1 0 U2 4 PU SPRINGER HEIDELBERG PI HEIDELBERG PA TIERGARTENSTRASSE 17, D-69121 HEIDELBERG, GERMANY SN 0947-7047 J9 IONICS JI Ionics PD JAN PY 1999 VL 5 IS 1-2 BP 115 EP 121 DI 10.1007/BF02375914 PG 7 WC Chemistry, Physical; Electrochemistry; Physics, Condensed Matter SC Chemistry; Electrochemistry; Physics GA V18TW UT WOS:000208028100020 ER PT B AU Xu, TF Carrie, R Dickerhoff, D Fisk, B Levinson, R McWilliams, J Wang, D Modera, M AF Xu, TF Carrie, R Dickerhoff, D Fisk, B Levinson, R McWilliams, J Wang, D Modera, M BE Zhao, RY Burnet, J TI Duct system performance and energy losses in large commercial buildings SO ISHVAC 99: 3RD INTERNATIONAL SYMPOSIUM ON HEATING, VENTILATION AND AIR CONDITIONING, VOLS 1 AND 2 LA English DT Proceedings Paper CT 3rd International Symposium on Heating, Ventilation and Air Conditioning (ISHVAC 99) CY NOV 17-19, 1999 CL SHENZHEN, PEOPLES R CHINA SP Tsinghua Univ, Hong Kong Polytech Univ, Amer Soc Heating, Refrigerating & Air Conditioning Engineers, Chartered Inst Bldg Serv Engineers, Hong Kong Inst Engineers, Chinese Architecture Assoc, Comm Heating Ventilat & Air Conditioning, China Assoc Refrigerat, Nat Sci Fdn China, Soc Heating Air Conditioning & Sanitary Engn Japan AB This paper presents the findings of recent work characterizing thermal distribution systems in four large commercial buildings by the Lawrence Berkeley National Laboratory (LBNL). The buildings are multi-story large-office buildings or retails buildings with floor spaces of more than 2,000 m(2). They typically contain single-duct or dual-duct constant air volume (CAV) systems, or variable air volume (VAV) systems. Thermal distribution losses in the duct systems studied are categorized into air leakage and conduction, with the latter including convective and radiative losses. This paper reports air leakage results in terms of effective leakage area (ELA)and ASHRAE-defined duct leakage class, and compares with those found in previous studies. The new data of leakage classes indicate that air leakage in large commercial duct systems varies significantly from system to system, and from system section to system section. Most of the duct systems measured are much leakier than the ductwork specified as "unsealed ducts" by ASHRAE. Energy losses due to air leakage and heat conduction through duct systems are significant. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Indoor Environm Dept, Berkeley, CA 94720 USA. RP Xu, TF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Indoor Environm Dept, Berkeley, CA 94720 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU TSINGHUA UNIV, DEPT THERMAL ENGINEERING, DIV HVAC PI BEIJING PA BEIJING 100084, PEOPLES R CHINA BN 962-367-255-1 PY 1999 BP 1065 EP 1073 PG 9 WC Construction & Building Technology SC Construction & Building Technology GA BP31H UT WOS:000084659400122 ER PT J AU Sherby, OD AF Sherby, OD TI Ultrahigh carbon steels, Damascus steels and ancient blacksmiths SO ISIJ INTERNATIONAL LA English DT Review DE ultrahigh carbon steels; processing; superplasticity; mechanical properties; Damascus Steel; Japanese swords; ancient blacksmiths ID IRON CARBIDE; SUPERPLASTICITY; MICROSTRUCTURE; BEHAVIOR; CERAMICS; ALLOYS AB The processing and mechanical properties of ultrahigh carbon steels (UHCS) have been studied over the past twenty-five years, initially at Stanford University and later at Lawrence Livermore National laboratory These studies have shown that such steels (1 to 2.1% C) can be made superplastic at elevated temperature, and have high strength and good ductility at room temperature. The metallurgy of UHCSs is now well understood allowing economical procedures to achieve ultra-fine hypereutectoid spheroidite, pearlite and optically-unresolvable martensite. The investigation of these UHCSs brought us, eventually, to study the his tory and metallurgy of Damascus steel and Japanese swords, and of ancient blacksmiths. These ancient Persian and Japanese weapons, the most famous in the world, were also ultrahigh carbon steels. It is proposed that the iron age may have begun at the same time period as the early bronze age, approximately 7000 BC. The Damascus steel age began at about 2000 BC, the same as the full bronze age. C1 Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Sherby, OD (reprint author), Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA. NR 56 TC 28 Z9 36 U1 7 U2 43 PU IRON STEEL INST JAPAN KEIDANREN KAIKAN PI TOKYO PA 9-4 OTEMACHI 1-CHOME CHIYODA-KU, TOKYO, 100, JAPAN SN 0915-1559 J9 ISIJ INT JI ISIJ Int. PY 1999 VL 39 IS 7 BP 637 EP 648 DI 10.2355/isijinternational.39.637 PG 12 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 217WK UT WOS:000081521800003 ER PT J AU Vitek, JM AF Vitek, JM TI Neural networks applied to welding: Two examples SO ISIJ INTERNATIONAL LA English DT Article DE neural networks; weld pool shape; laser welds; welding; ferrite number; stainless steel AB Neural network analysis provides for a powerful means for non-linear regression analysis that can be applied to a wide variety of problems. This paper describes the application of neural networks to two welding areas. The general approach for the development of the back propagation neural networks is described, including the method that was used to identify the optimum neural network architecture and the best neural network. The first application considers the weld profile shape in pulsed laser aluminum welds and the prediction of the profiles as a function of weld process conditions. It is shown that the neural network predictions are reasonably accurate in most cases, in spite of the fact that the training data set was quite small. The second application considers the prediction of Ferrite Number in stainless steel welds as a function of weld composition. For this application an extensive training data set was available. The neural network that was developed was compared to conventional means for predicting Ferrite Number and it was shown that the neural network was considerably more accurate than other currently available methods. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Vitek, JM (reprint author), Oak Ridge Natl Lab, POB 2008,Bldg 550,MS 6376, Oak Ridge, TN 37831 USA. NR 16 TC 9 Z9 9 U1 1 U2 2 PU IRON STEEL INST JAPAN KEIDANREN KAIKAN PI TOKYO PA 9-4 OTEMACHI 1-CHOME CHIYODA-KU, TOKYO, 100, JAPAN SN 0915-1559 J9 ISIJ INT JI ISIJ Int. PY 1999 VL 39 IS 10 BP 1088 EP 1095 DI 10.2355/isijinternational.39.1088 PG 8 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 247KP UT WOS:000083220200018 ER PT J AU McIlroy, A AF McIlroy, A TI Laser studies of small radicals in rich methane flames: OH, HCO, and (CH2)-C-1 SO ISRAEL JOURNAL OF CHEMISTRY LA English DT Article ID ABSORPTION SPECTROSCOPY DETECTION; AROMATIC HYDROCARBON FORMATION AB Chemical mechanisms for combustion processes are often developed for nearly stoichiometric flames, a perfect balance of fuel and oxidizer. As the fuel content is increased and flames become richer, these models will eventually break down because they lack reactions leading to the formation of larger hydrocarbons and ultimately soot. In this contribution, we investigate the behavior of two methane combustion models, the GRI 2.11 and Prada-Miller mechanisms, in a series of rich flames of stoichiometry 1.0, 1.2, 1.4, and 1.6. Using non-intrusive laser diagnostics, laser-induced fluorescence, and cavity ring-down spectroscopy, the concentration profiles as a function of height above burner for OH, HCO, and (CH2)-C-1 have been measured in these rich low-pressure methane flames. The experimental results are compared to the calculated profiles. In general, good agreement is found for all species over the range of stoichiometries investigated. The agreement of the OH and HCO profiles with the models is particularly striking. For (CH2)-C-1, the width, position, and relative height of the profiles match the model predictions for flames of stoichiometry 1.0 and 1.2. Discrepancies are noted for the richer flames investigated, those with stoichiometries of 1.4 and 1.6. An analysis of the models suggests that additional pathways for (CH2)-C-1 formation and removal should be considered. Even under fairly rich conditions, stoichiometry of 1.6, both models perform well for the radicals investigated here. There is no indication of the requirement for >C-2 chemistry to reproduce the present data. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP McIlroy, A (reprint author), Sandia Natl Labs, Mail Stop 9055, Livermore, CA 94551 USA. NR 21 TC 17 Z9 18 U1 2 U2 5 PU LASER PAGES PUBL LTD PI JERUSALEM PA MERKAZ SAPIR 6/37, GIVAT SHAUL PO BOX 35409, JERUSALEM 91352, ISRAEL SN 0021-2148 J9 ISRAEL J CHEM JI Isr. J. Chem. PY 1999 VL 39 IS 1 BP 55 EP 62 PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA 219WE UT WOS:000081630100006 ER PT J AU Tonse, SR Moriarty, NW Brown, NJ Frenklach, M AF Tonse, SR Moriarty, NW Brown, NJ Frenklach, M TI PRISM: Piecewise reusable implementation of solution mapping. an economical strategy for chemical kinetics SO ISRAEL JOURNAL OF CHEMISTRY LA English DT Article ID SITU ADAPTIVE TABULATION; MECHANISMS; COMBUSTION; CHEMISTRY AB In a chemical kinetics calculation, a solution-mapping procedure is applied to parametrize the solution of the initial-value ordinary differential equation system as a set of algebraic polynomial equations. To increase the accuracy, the parametrization is done piecewise, dividing the multidimensional chemical composition space into hypercubes and constructing polynomials for each hypercube. A differential equation solver is used to provide the solution at selected points throughout a hypercube, and from these solutions the polynomial coefficients are determined. Factorial design methods are used to reduce the required number of computed points. The polynomial coefficients for each hypercube are stored in a data structure for subsequent reuse, since over the duration of a flame simulation it is likely that a particular set of concentrations and temperature will occur repeatedly at different times and positions. The method is applied to H-2-air combustion using an 8-species reaction set. After N-2 is added as an inert species and enthalpy is considered, this results in a 10-dimensional chemical composition space. To add the capability of using a variable time-step, time-step is added as an additional dimension, making an 11-dimensional space. Reactive fluid dynamical simulations of a 1-D laminar premixed flame and a 2-D turbulent non-premixed jet are performed. The results are compared to identical control runs which use an ordinary differential equation solver to calculate the chemical kinetic rate equations. The resulting accuracy is very good, and a factor of 10 increase in computational efficiency is attained. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. RP Tonse, SR (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. NR 23 TC 70 Z9 76 U1 0 U2 4 PU LASER PAGES PUBL LTD PI JERUSALEM PA MERKAZ SAPIR 6/37, GIVAT SHAUL PO BOX 35409, JERUSALEM 91352, ISRAEL SN 0021-2148 J9 ISRAEL J CHEM JI Isr. J. Chem. PY 1999 VL 39 IS 1 BP 97 EP 106 PG 10 WC Chemistry, Multidisciplinary SC Chemistry GA 219WE UT WOS:000081630100010 ER PT J AU Pomes, R AF Pomes, R TI Theoretical studies of the Grotthuss mechanism in biological proton wires SO ISRAEL JOURNAL OF CHEMISTRY LA English DT Article; Proceedings Paper CT Reserch Workshop on Proton Solvation and Proton Mobility CY 1998 CL NEVE ILAN, ISRAEL SP Israel Proton Transfer Grp, Israel Sci Fdn, Ben Gurion Univ Negev, Tel Aviv Univ, Hebrew Univ Jerusalem, Fritz Haber Res Ctr Molec Dynam, Spectra Phys ID MOLECULAR-DYNAMICS SIMULATIONS; CYTOCHROME-C-OXIDASE; HEME-COPPER OXIDASES; CHANNEL GRAMICIDIN-A; WATER-MOLECULES; EXCESS PROTON; QUANTUM DYNAMICS; H+ TRANSLOCATION; TRANSPORT; CHAIN AB The structural, dynamic, and thermodynamic properties of proton wires are examined. Detailed molecular aspects of both hop and turn steps of the Grotthuss mechanism for proton conduction along single-file chains of water molecules in model nonpolar pores and in the gramicidin A channel are reviewed, and new simulation results are presented. The Grotthuss mechanism is discussed and analyzed in terms of hydrogen-bonded network structure and connectivity, and the properties of proton wires are contrasted to those of bulk water. General considerations regarding the biological relevance of such studies are proposed. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Pomes, R (reprint author), Hosp Sick Children, 555 Univ Ave, Toronto, ON M5G 1X8, Canada. NR 43 TC 20 Z9 20 U1 1 U2 4 PU LASER PAGES PUBL LTD PI JERUSALEM PA MERKAZ SAPIR 6/37, GIVAT SHAUL PO BOX 35409, JERUSALEM 91352, ISRAEL SN 0021-2148 J9 ISRAEL J CHEM JI Isr. J. Chem. PY 1999 VL 39 IS 3-4 BP 387 EP 395 PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 281EU UT WOS:000085145600018 ER PT S AU Foster I Kesselman, C Lee, C Lindell, B Nahrstedt, K Roy, A AF Foster, I Kesselman, C Lee, C Lindell, B Nahrstedt, K Roy, A GP IEEE IEEE TI A distributed resource management architecture that supports advance reservations and co-allocation SO IWQOS '99: 1999 SEVENTH INTERNATIONAL WORKSHOP ON QUALITY OF SERVICE SE International Workshop on Quality of Service LA English DT Proceedings Paper CT 7th International Workshop on Quality of Service (IWQOS 99) CY MAY 31-JUN 04, 1999 CL LONDON, ENGLAND SP IEEE Commun Soc, IFIP WG6 1 Assoc, ACM SIGCOMM, Nortel Res UK, Hewlett Packard Internet Res Inst, Microsoft Res, Sprint Labs AB dThe realization of end-to-end quality of service (QoS) guarantees in emerging network-based applications requires mechanisms that support first dynamic discovery and then advance or immediate reservation of resources that will often be heterogeneous in type and implementation and independently controlled and administered. We propose the Globus Architecture for Reservation and Allocation (GARA) to address these four issues. GARA treats both reservations and computational elements such as processes, network flows, and memory blocks as first class entities, allowing them to be created, monitored, and managed independently and uniformly. It simplifies management of heterogeneous resource types by defining uniform mechanisms for computers, networks, disk, memory, and other resources. Layering on these standard mechanisms, GARA enables the construction of application-level co-reservation and co-allocation libraries that applications can use to dynamically assemble collections of resources, guided by both application QoS requirements and the local administration policy of individual resources. We describe a prototype GARA implementation that supports three different resource types-parallel computers, individual CPUs under control of the Dynamic Soft Real-Time scheduler, and Integrated Services networks-and provide performance results that quantify the costs of our techniques. C1 Argonne Natl Lab, Math & Comp Sci Div, Argonne, IL 60439 USA. RP Foster I (reprint author), Argonne Natl Lab, Math & Comp Sci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 20 TC 13 Z9 16 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1548-615X BN 0-7803-5671-3 J9 INT WORKSH QUAL SERV PY 1999 BP 27 EP 36 DI 10.1109/IWQOS.1999.766475 PG 10 WC Computer Science, Information Systems SC Computer Science GA BN37L UT WOS:000081719000006 ER PT B AU Miller, MK AF Miller, MK BE Koiwa, M Otsuka, K Miyazaki, T TI Atom probe studies of phase transformations in nickel-based superalloys SO JAPAN INSTITUTE OF METALS, PROCEEDINGS, VOL 12, (JIMIC-3), PTS 1 AND 2: SOLID - SOLID PHASE TRANSFORMATIONS LA English DT Proceedings Paper CT International Conference on Solid-Solid Phase Transformations (PTM 99) CY MAY 24-28, 1999 CL KYOTO, JAPAN SP Japan Inst Met, Iron & Steel Inst Japan, Phys Soc Japan, Mat Sci Soc Japan, Chem Soc Japan, Crystallog Soc Japan, Soc Polymer Sci, Japanese Assoc Crystal Growth, Japan Soc Heat Treatment, Atomic Energy Soc Japan, Surface Sci Soc Japan, Japan Welding Engn Soc, Min & Mat Proc Inst Japan, Japan Soc Corros Engn, Japan Soc Powder & Powder Met, Chinese Soc Met, Federat European Met Soc, Soc Francaise Met & Mat, Soc Francaise Phys, Deutsch Gesell Materialkunde E V, Inst Nazl Fisica Mat, Korean Inst Met & Mat, Swedish Soc Mat Technol, Inst Mat, Minerals Met & Mat Soc DE Atom Probe Field Ion Microscopy; Atom Probe Tomography; superalloy; precipitation AB An atom probe tomography characterization of the early stages of phase separation in a commercial nickel-base superalloy, Alloy 718, has been performed. The development of the composition and structure of the secondary precipitates that formed on ageing at 873 K has been characterized. The secondary precipitates were not found to be uniform throughout their volume but to be divided into two distinct types of regions enriched in either niobium or in aluminum and titanium that are characteristic of the gamma " and gamma' phases, respectively. C1 Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, Oak Ridge, TN 37831 USA. RP Miller, MK (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, POB 2008, Oak Ridge, TN 37831 USA. NR 7 TC 0 Z9 0 U1 0 U2 2 PU JAPAN INST METALS PI SENDAI PA AOBA ARAMAKI, SENDAI, 980, JAPAN BN 4-88903-401-3 PY 1999 BP 73 EP 76 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BP88D UT WOS:000086479100013 ER PT B AU Turchi, PEA Mayou, D Julien, JP AF Turchi, PEA Mayou, D Julien, JP BE Koiwa, M Otsuka, K Miyazaki, T TI Integrated quantum-mechanical approach to stability, chemical order and phase evolution in complex alloys SO JAPAN INSTITUTE OF METALS, PROCEEDINGS, VOL 12, (JIMIC-3), PTS 1 AND 2: SOLID - SOLID PHASE TRANSFORMATIONS LA English DT Proceedings Paper CT International Conference on Solid-Solid Phase Transformations (PTM 99) CY MAY 24-28, 1999 CL KYOTO, JAPAN SP Japan Inst Met, Iron & Steel Inst Japan, Phys Soc Japan, Mat Sci Soc Japan, Chem Soc Japan, Crystallog Soc Japan, Soc Polymer Sci, Japanese Assoc Crystal Growth, Japan Soc Heat Treatment, Atomic Energy Soc Japan, Surface Sci Soc Japan, Japan Welding Engn Soc, Min & Mat Proc Inst Japan, Japan Soc Corros Engn, Japan Soc Powder & Powder Met, Chinese Soc Met, Federat European Met Soc, Soc Francaise Met & Mat, Soc Francaise Phys, Deutsch Gesell Materialkunde E V, Inst Nazl Fisica Mat, Korean Inst Met & Mat, Swedish Soc Mat Technol, Inst Mat, Minerals Met & Mat Soc DE electronic structure; LMTO-ASA; CPA; GPM; ECM; CVM; effective interactions; stability; chemical order; phase diagram AB We first briefly review and illustrate the application of a state-of-the art approach to the study of phase stability properties of substitutional alloys based on periodic lattices with the prediction of the phase diagram of Ta-W. Then, we schematically present a real-space approach based on electronic structure calculations for studying stability, chemical order and phase evolution in the case of multi-component alloys which exhibit both chemical order and topological disorder. Potential applications, and preliminary results will be discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Turchi, PEA (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-353,POB 808, Livermore, CA 94551 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU JAPAN INST METALS PI SENDAI PA AOBA ARAMAKI, SENDAI, 980, JAPAN BN 4-88903-401-3 PY 1999 BP 625 EP 628 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BP88D UT WOS:000086479100137 ER PT B AU Vitek, JM David, SA AF Vitek, JM David, SA BE Koiwa, M Otsuka, K Miyazaki, T TI Using neural networks to describe complex phase transformation behavior SO JAPAN INSTITUTE OF METALS, PROCEEDINGS, VOL 12, (JIMIC-3), PTS 1 AND 2: SOLID - SOLID PHASE TRANSFORMATIONS LA English DT Proceedings Paper CT International Conference on Solid-Solid Phase Transformations (PTM 99) CY MAY 24-28, 1999 CL KYOTO, JAPAN SP Japan Inst Met, Iron & Steel Inst Japan, Phys Soc Japan, Mat Sci Soc Japan, Chem Soc Japan, Crystallog Soc Japan, Soc Polymer Sci, Japanese Assoc Crystal Growth, Japan Soc Heat Treatment, Atomic Energy Soc Japan, Surface Sci Soc Japan, Japan Welding Engn Soc, Min & Mat Proc Inst Japan, Japan Soc Corros Engn, Japan Soc Powder & Powder Met, Chinese Soc Met, Federat European Met Soc, Soc Francaise Met & Mat, Soc Francaise Phys, Deutsch Gesell Materialkunde E V, Inst Nazl Fisica Mat, Korean Inst Met & Mat, Swedish Soc Mat Technol, Inst Mat, Minerals Met & Mat Soc DE computational analysis; constitution diagrams; Ferrite Number; neural networks; stainless steels; welding AB Final microstructures can often be the end result of a complex sequence of phase transformations. Fundamental analyses may be used to model various stages of the overall behavior but they are often impractical or cumbersome when considering multicomponent systems covering a wide range of compositions. Neural network analysis may be a useful alternative method of identifying and describing phase transformation behavior. A neural network model for ferrite prediction in stainless steel welds is described. It is shown that the neural network analysis provides valuable information that accounts for alloying element interactions. It is suggested that neural network analysis may be extremely useful for analysis when more fundamental approaches are unavailable or overly burdensome. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Vitek, JM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU JAPAN INST METALS PI SENDAI PA AOBA ARAMAKI, SENDAI, 980, JAPAN BN 4-88903-401-3 PY 1999 BP 741 EP 744 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BP88D UT WOS:000086479100165 ER PT B AU Shapiro, SM AF Shapiro, SM BE Koiwa, M Otsuka, K Miyazaki, T TI Neutron scattering studies of pre-transitional effects in solid-solid phase transformations SO JAPAN INSTITUTE OF METALS, PROCEEDINGS, VOL 12, (JIMIC-3), PTS 1 AND 2: SOLID - SOLID PHASE TRANSFORMATIONS LA English DT Proceedings Paper CT International Conference on Solid-Solid Phase Transformations (PTM 99) CY MAY 24-28, 1999 CL KYOTO, JAPAN SP Japan Inst Met, Iron & Steel Inst Japan, Phys Soc Japan, Mat Sci Soc Japan, Chem Soc Japan, Crystallog Soc Japan, Soc Polymer Sci, Japanese Assoc Crystal Growth, Japan Soc Heat Treatment, Atomic Energy Soc Japan, Surface Sci Soc Japan, Japan Welding Engn Soc, Min & Mat Proc Inst Japan, Japan Soc Corros Engn, Japan Soc Powder & Powder Met, Chinese Soc Met, Federat European Met Soc, Soc Francaise Met & Mat, Soc Francaise Phys, Deutsch Gesell Materialkunde E V, Inst Nazl Fisica Mat, Korean Inst Met & Mat, Swedish Soc Mat Technol, Inst Mat, Minerals Met & Mat Soc DE Martensite; neutrons; lattice dynamics; phonons; phase transitions ID MARTENSITIC-TRANSFORMATION; CRYSTAL-STRUCTURE; NI2MNGA; ALLOYS AB Neutron scattering studies have played a fundamental role in understanding solid-solid phase transformations, particularly in studying the lattice dynamical behavior associated with precursor effects. A review of the studies performed on solids exhibiting Martensitic transformations is given below. The mode softening and associated elastic diffuse scattering, previously observed in NiAl alloys, will be discussed as well as more recent work on Ni2MnGa, a system exhibiting magnetic order as well as a Martensitic transformation. Also, new results on the precursor effects in ordered and disordered FePt alloys will be presented. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Shapiro, SM (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 21 TC 0 Z9 0 U1 2 U2 3 PU JAPAN INST METALS PI SENDAI PA AOBA ARAMAKI, SENDAI, 980, JAPAN BN 4-88903-401-3 PY 1999 BP 799 EP 806 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BP88D UT WOS:000086479100177 ER PT B AU Saxena, A Lookman, T Shenoy, SR Bishop, AR AF Saxena, A Lookman, T Shenoy, SR Bishop, AR BE Koiwa, M Otsuka, K Miyazaki, T TI Elastic compatibility, martensitic textures and weak plasticity SO JAPAN INSTITUTE OF METALS, PROCEEDINGS, VOL 12, (JIMIC-3), PTS 1 AND 2: SOLID - SOLID PHASE TRANSFORMATIONS LA English DT Proceedings Paper CT International Conference on Solid-Solid Phase Transformations (PTM 99) CY MAY 24-28, 1999 CL KYOTO, JAPAN SP Japan Inst Met, Iron & Steel Inst Japan, Phys Soc Japan, Mat Sci Soc Japan, Chem Soc Japan, Crystallog Soc Japan, Soc Polymer Sci, Japanese Assoc Crystal Growth, Japan Soc Heat Treatment, Atomic Energy Soc Japan, Surface Sci Soc Japan, Japan Welding Engn Soc, Min & Mat Proc Inst Japan, Japan Soc Corros Engn, Japan Soc Powder & Powder Met, Chinese Soc Met, Federat European Met Soc, Soc Francaise Met & Mat, Soc Francaise Phys, Deutsch Gesell Materialkunde E V, Inst Nazl Fisica Mat, Korean Inst Met & Mat, Swedish Soc Mat Technol, Inst Mat, Minerals Met & Mat Soc DE branched twins; external stress; edge dislocation; Ginzburg-Landau simulation ID DYNAMICS AB We consider a model free energy for 2D martensitic transitions, that provides a unified understanding of various twin/tweed and branched twin textures in the presence of external stress. The free energy is a triple well potential in the deviatoric strains (order parameter). Random compositional fluctuations are gradient-coupled to the order parameter in a "local-stress" model. We find that the compatibility condition (linking various strain tensor components), together with local variations such as interfaces or compositional fluctuations, can drive the formation of global elastic textures, through long-range and anisotropic effective (deviatoric) strain interactions. Relaxational computer simulations using the time-dependent Ginzburg-Landau equation show the spontaneous formation of twins, branched twins and tweed. We also study the effect of stress due to an edge dislocation. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Saxena, A (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU JAPAN INST METALS PI SENDAI PA AOBA ARAMAKI, SENDAI, 980, JAPAN BN 4-88903-401-3 PY 1999 BP 859 EP 862 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BP88D UT WOS:000086479100187 ER PT B AU Babu, SS David, SA Vitek, JM AF Babu, SS David, SA Vitek, JM BE Koiwa, M Otsuka, K Miyazaki, T TI Thermo-chemical-mechanical effects on microstructure development in low-alloy steel welds SO JAPAN INSTITUTE OF METALS, PROCEEDINGS, VOL 12, (JIMIC-3), PTS 1 AND 2: SOLID - SOLID PHASE TRANSFORMATIONS LA English DT Proceedings Paper CT International Conference on Solid-Solid Phase Transformations (PTM 99) CY MAY 24-28, 1999 CL KYOTO, JAPAN SP Japan Inst Met, Iron & Steel Inst Japan, Phys Soc Japan, Mat Sci Soc Japan, Chem Soc Japan, Crystallog Soc Japan, Soc Polymer Sci, Japanese Assoc Crystal Growth, Japan Soc Heat Treatment, Atomic Energy Soc Japan, Surface Sci Soc Japan, Japan Welding Engn Soc, Min & Mat Proc Inst Japan, Japan Soc Corros Engn, Japan Soc Powder & Powder Met, Chinese Soc Met, Federat European Met Soc, Soc Francaise Met & Mat, Soc Francaise Phys, Deutsch Gesell Materialkunde E V, Inst Nazl Fisica Mat, Korean Inst Met & Mat, Swedish Soc Mat Technol, Inst Mat, Minerals Met & Mat Soc DE low-alloy steels; delta-ferrite; austenite; acicular ferrite; bainite; and stress-relaxation AB The effect of aluminum on the decomposition of delta ferrite to austenite was investigated in a low-alloy steel weld. In addition, the effect of inclusion composition on the transition from bainite to acicular ferrite during austenite decomposition was analyzed. Stress relaxation during decomposition of austenite to allotriomorphic and acicular ferrite was also characterized. Results from the above experiments illustrate the importance of thermomechanical effects on weld microstructure evolution. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Babu, SS (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Babu, Sudarsanam/D-1694-2010 OI Babu, Sudarsanam/0000-0002-3531-2579 NR 9 TC 0 Z9 0 U1 0 U2 1 PU JAPAN INST METALS PI SENDAI PA AOBA ARAMAKI, SENDAI, 980, JAPAN BN 4-88903-401-3 PY 1999 BP 1565 EP 1568 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BP88D UT WOS:000086479100349 ER PT B AU Turchi, PEA AF Turchi, PEA BE Koiwa, M Otsuka, K Miyazaki, T TI Focus group on atomistic and phase field simulations of materials evolution and properties SO JAPAN INSTITUTE OF METALS, PROCEEDINGS, VOL 12, (JIMIC-3), PTS 1 AND 2: SOLID - SOLID PHASE TRANSFORMATIONS LA English DT Proceedings Paper CT International Conference on Solid-Solid Phase Transformations (PTM 99) CY MAY 24-28, 1999 CL KYOTO, JAPAN SP Japan Inst Met, Iron & Steel Inst Japan, Phys Soc Japan, Mat Sci Soc Japan, Chem Soc Japan, Crystallog Soc Japan, Soc Polymer Sci, Japanese Assoc Crystal Growth, Japan Soc Heat Treatment, Atomic Energy Soc Japan, Surface Sci Soc Japan, Japan Welding Engn Soc, Min & Mat Proc Inst Japan, Japan Soc Corros Engn, Japan Soc Powder & Powder Met, Chinese Soc Met, Federat European Met Soc, Soc Francaise Met & Mat, Soc Francaise Phys, Deutsch Gesell Materialkunde E V, Inst Nazl Fisica Mat, Korean Inst Met & Mat, Swedish Soc Mat Technol, Inst Mat, Minerals Met & Mat Soc C1 LLNL, Livermore, CA 94551 USA. RP Turchi, PEA (reprint author), LLNL, L-353,POB 808, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU JAPAN INST METALS PI SENDAI PA AOBA ARAMAKI, SENDAI, 980, JAPAN BN 4-88903-401-3 PY 1999 BP 1671 EP 1673 PG 3 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BP88D UT WOS:000086479100376 ER PT J AU Murakami, Y Hill, JP Gibbs, D Blume, M Kawada, H Koyama, I Tanaka, M Kawata, H Arima, T Moritomo, Y Tokura, Y Hirota, K Endoh, Y AF Murakami, Y Hill, JP Gibbs, D Blume, M Kawada, H Koyama, I Tanaka, M Kawata, H Arima, T Moritomo, Y Tokura, Y Hirota, K Endoh, Y TI Direct observation of charge and orbital ordering by resonant X-ray scattering SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS LA English DT Article; Proceedings Paper CT 2nd International Conference on Synchrotron Radiation in Materials Science (SRMS-2) CY OCT 31-NOV 03, 1998 CL KOBE, JAPAN SP Japan Atomic Energy Res Inst, Inst Phys & Chem Res, Japan Synchrotron Radiat Res Inst DE charge-ordering; orbital-ordering; anomalous dispersion; resonant x-ray scattering ID FORBIDDEN REFLECTIONS; ANOMALOUS SCATTERING; LAMNO3; MAGNETORESISTANCE; POLARIZATION; TRANSITION; BROMATE; FILMS AB Charge and orbital ordering states of manganites have been observed directly by using synchrotron x-ray diffraction techniques. The alternating pattern of Mn3+ and Mn4+ in charge ordering state was elucidated by the anomalous dispersion method. The orbital ordering at Mn3+ sites is presented based on resonant x-ray scattering near Mn K-absorption edge. The scattering mechanism has been developed by considering the splitting of the Mn 4p levels due to the orbital ordering. The coupling among the charge, spin and orbital degrees of freedom is discussed. C1 High Energy Accelerator Res Org, Inst Mat Struct Sci, Photon Factory, Tsukuba, Ibaraki 3050801, Japan. Core Res Evolut Sci & Technol, Tsukuba, Ibaraki 3050047, Japan. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Tsukuba, Inst Mat Sci, Tsukuba, Ibaraki 3058573, Japan. Nagoya Univ, Ctr Intergrated Res Sci & Engn, Nagoya, Aichi 4640814, Japan. Univ Tokyo, Dept Appl Phys, Tokyo 1130033, Japan. Joint Res Ctr Atom Technol, Tsukuba, Ibaraki 3050046, Japan. Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan. RP High Energy Accelerator Res Org, Inst Mat Struct Sci, Photon Factory, Tsukuba, Ibaraki 3050801, Japan. RI Arima, Taka-hisa/G-9217-2012; Tokura, Yoshinori/C-7352-2009 NR 28 TC 3 Z9 3 U1 0 U2 2 PU JAPAN SOC APPLIED PHYSICS PI TOKYO PA KUDAN-KITA BUILDING 5TH FLOOR, 1-12-3 KUDAN-KITA, CHIYODA-KU, TOKYO, 102-0073, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Brief Commun. Rev. Pap. PY 1999 VL 38 SU 1 BP 360 EP 364 PG 5 WC Physics, Applied SC Physics GA 240AT UT WOS:000082804000089 ER PT J AU Sinha, SK AF Sinha, SK TI New developments in the application of synchrotron radiation to material science SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article; Proceedings Paper CT 2nd International Conference on Synchrotron Radiation in Materials Science (SRMS-2) CY OCT 31-NOV 03, 1998 CL KOBE, JAPAN SP Japan Atomic Energy Res Inst, Inst Phys & Chem Res, Japan Synchrotron Radiat Res Inst DE microfocusing; microbeams; microdiffraction; X-ray microscopy; residual stress; coherence; photon correlation spectroscopy; polymer films; magnetic roughness; CMR materials ID X-RAY-SCATTERING; CORRELATION SPECTROSCOPY; SURFACE; DYNAMICS; FILMS; FLUCTUATIONS; INTERFACES; BROMATE; MATTER AB Recent developments in the application of synchrotron radiation to materials science are discussed, using techniques which exploit the high brilliance of the newer synchrotron sources, such as microbeam techniques and correlation spectroscopy. These include studies of environmental systems, residual stress, slow dynamics of condensed matter systems and studies of liquid surfaces and thin magnetic films. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Sinha, SK (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. NR 45 TC 1 Z9 1 U1 0 U2 0 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PY 1999 VL 38 SU 1 BP 1 EP 7 PG 7 WC Physics, Applied SC Physics GA 240AT UT WOS:000082804000002 ER PT J AU Hill, JP Kao, CC Von Zimmermann, M Hamalainen, K Huotari, S Berman, LE Caliebe, WAL Hirota, K Matsubara, M Kotani, A Peng, JL Greene, RL Tsukada, I Masuda, T Uchinokura, K AF Hill, JP Kao, CC Von Zimmermann, M Hamalainen, K Huotari, S Berman, LE Caliebe, WAL Hirota, K Matsubara, M Kotani, A Peng, JL Greene, RL Tsukada, I Masuda, T Uchinokura, K TI Resonant inelastic x-ray scattering from strongly correlated copper oxides SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article; Proceedings Paper CT 2nd International Conference on Synchrotron Radiation in Materials Science (SRMS-2) CY OCT 31-NOV 03, 1998 CL KOBE, JAPAN SP Japan Atomic Energy Res Inst, Inst Phys & Chem Res, Japan Synchrotron Radiat Res Inst DE resonant inelastic x-ray scattering; copper oxides; charge transfer ID K-EDGE; ABSORPTION; ND2CUO4; SPECTRA AB We report resonant inelastic x-ray scattering from Nd2CuO4 and two other copper oxides, YBa2Cu3O7-delta and CuGeO3. In each case an excitation of similar to 6 eV is observed when the incident photon energy is tuned through the Cu K-edge. Calculations for Nd2CuO4, based on the Anderson impurity model identify this as a charge transfer excitation to the antibonding state. For Nd2CuO4, the incident energy dependence of the inelastic intensity exhibits a single resonance at 8990 eV, corresponding to a <(1s)under bar>3d(0)4(kappa), intermediate state. The absence of a resonance associated with the <(1s)under bar>3d(0)(L) under bar 4p(kappa) intermediate state is attributed to non-local effects. Preliminary results from CuCeO3, which exhibit two resonances support this conclusion. 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. Tohoku Univ, Dept Phys, Sendai, Miyagi 980, Japan. Univ Tokyo, Inst Solid State Phys, Minato Ku, Tokyo 106, Japan. Univ Maryland, Dept Phys & Astron, Ctr Superconduct Res, College Pk, MD 20742 USA. Univ Tokyo, Dept Appl Phys, Bunkyo Ku, Tokyo 113, Japan. RP Hill, JP (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Hamalainen, Keijo/A-3986-2010 OI Hamalainen, Keijo/0000-0002-9234-9810 NR 12 TC 1 Z9 1 U1 0 U2 0 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PY 1999 VL 38 SU 1 BP 118 EP 121 PG 4 WC Physics, Applied SC Physics GA 240AT UT WOS:000082804000030 ER PT J AU You, H Chu, YS Lister, TE Nagy, Z AF You, H Chu, YS Lister, TE Nagy, Z TI Electrochemical interfaces of porous silicon and ruthenium dioxide SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article; Proceedings Paper CT 2nd International Conference on Synchrotron Radiation in Materials Science (SRMS-2) CY OCT 31-NOV 03, 1998 CL KOBE, JAPAN SP Japan Atomic Energy Res Inst, Inst Phys & Chem Res, Japan Synchrotron Radiat Res Inst DE electrochemistry; surface x-ray scattering; porous silicon; ruthenium dioxide; ultracapacitor ID X-RAY-REFLECTIVITY; N-TYPE SILICON; TRANSMISSION GEOMETRY; ELECTRODES; SCATTERING; SURFACE; GROWTH AB Study of electrochemical interfaces of non-metallic electrodes with synchrotron x-ray scattering technique is reported. Our recent in situ investigation of porous silicon during anodic dissolution and of ruthenium dioxide single crystals under reduction/oxidation electrochemical potential cycles are given as examples. In both cases, we show that the structural aspects uncovered by the synchrotron x-ray scattering techniques suggest direct relations to their non-structural properties of importance; for the porous silicon, the relation between the luminescence and pore structures, and for the ruthenium oxide, the relation between the modification of surface structure and the energy storage mechanism. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP You, H (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI You, Hoydoo/A-6201-2011 OI You, Hoydoo/0000-0003-2996-9483 NR 30 TC 4 Z9 4 U1 0 U2 1 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PY 1999 VL 38 SU 1 BP 239 EP 244 PG 6 WC Physics, Applied SC Physics GA 240AT UT WOS:000082804000060 ER PT J AU Hirai, A Takemoto, K Nishino, K Niemann, B Hettwer, M Rudolph, D Anderson, E Attwood, D Kern, DP Nakayama, Y Kihara, H AF Hirai, A Takemoto, K Nishino, K Niemann, B Hettwer, M Rudolph, D Anderson, E Attwood, D Kern, DP Nakayama, Y Kihara, H TI Transmission x-ray microscopy with 50 nm resolution installed at Ritsumeikan Synchrotron Radiation Center SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article DE transmission x-ray microscopy; zone plate; Rits SR Center; back-illuminated CCD ID ZONE PLATES; RING AB A transmission X-ray microscope having two zone plates has been developed at BL-12, Ritsumeikan Synchrotron Radiation Center (Rits SR Center). By incorporating a new: type of condenser zone plate (diameter 9 mm, zone number41,890; outermost zone width 53.7 nm) in the microscope, 50 nm resolution has been obtained from both knife edge test and star test pattern at a wavelength of 3.2 nm, and for diatoms, the 0.1 mu m inner structures have been clearly resolved. C1 Ritsumeikan Univ, Dept Phys, Kusatsu, Shiga 5258577, Japan. Kansai Med Univ, Phys Lab, Hirakata, Osaka 5731136, Japan. Univ Gottingen, Forschungseinrichtung Rontgenphys, D-37073 Gottingen, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. Univ Tubingen, Inst Angew Phys, Tubingen 1, Germany. RP Kihara, H (reprint author), Ritsumeikan Univ, Dept Phys, 1-1-1 Noji Higashi, Kusatsu, Shiga 5258577, Japan. EM fpc30013@se.ritsumei.ac.jp; kihara@makino.kmu.ac.jp NR 21 TC 17 Z9 17 U1 0 U2 3 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PD JAN PY 1999 VL 38 IS 1A BP 274 EP 278 DI 10.1143/JJAP.38.274 PG 5 WC Physics, Applied SC Physics GA 182BA UT WOS:000079477600059 ER PT J AU Tjeng, LH Brookes, NB Goedkoop, JB Sinkovic, B de Groot, FMF Hesper, R Altieri, S Pellegrin, E Tanaka, A Hulbert, SL Shekel, E Hien, NT Menovsky, AA Sawatzky, GA AF Tjeng, LH Brookes, NB Goedkoop, JB Sinkovic, B de Groot, FMF Hesper, R Altieri, S Pellegrin, E Tanaka, A Hulbert, SL Shekel, E Hien, NT Menovsky, AA Sawatzky, GA TI Study of magnetic materials using spin-resolved circularly-polarized resonant photoemission SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article; Proceedings Paper CT 2nd International Conference on Synchrotron Radiation in Materials Science (SRMS-2) CY OCT 31-NOV 03, 1998 CL KOBE, JAPAN SP Japan Atomic Energy Res Inst, Inst Phys & Chem Res, Japan Synchrotron Radiat Res Inst DE spin-resolved photoemission; soft-x-ray magnetic circular dichroism; strongly correlated solids ID ELECTRONIC-STRUCTURE; CUO; CU2O; SUPERCONDUCTORS; DICHROISM; LA2CUO4; HOLES AB We have recently demonstrated that it is possible to obtain spin-resolved valence band spectra with a very high degree of spin polarization from macroscopically non-magnetic transition metal materials if the excitation light is circularly polarized and has an energy close to the cation 2p(3/2) (L-3) white line. Using the layered compound Sr2CuO2Cl2 as a test system, we report in this paper that the degree of spin polarization is strongly dependent on the transition metal 3d orbital orientation relative to the Poynting vector of the light. C1 European Synchrotron Radiat Facil, F-38043 Grenoble, France. NYU, Dept Phys, New York, NY 10003 USA. Hiroshima Univ, Fac Sci, Dept Mat Sci, Higashihiroshima 7398526, Japan. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Groningen, Ctr Mat Sci, Solid State Phys Lab, NL-9747 AG Groningen, Netherlands. RP Tjeng, LH (reprint author), Univ Groningen, Ctr Mat Sci, Solid State Phys Lab, Nijenborgh 4, NL-9747 AG Groningen, Netherlands. RI Sawatzky, George/D-2997-2012; de Groot, Frank/A-1918-2009 NR 20 TC 3 Z9 3 U1 0 U2 2 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PY 1999 VL 38 SU 1 BP 344 EP 347 PG 4 WC Physics, Applied SC Physics GA 240AT UT WOS:000082804000086 ER PT J AU Seve, L Jaouen, N Tonnerre, JM Raoux, D Arend, M Felsch, W Bartolome, F Rogalev, A Goulon, J Chakarian, V AF Seve, L Jaouen, N Tonnerre, JM Raoux, D Arend, M Felsch, W Bartolome, F Rogalev, A Goulon, J Chakarian, V TI 5d and 4f magnetic profiles in Ce/Fe multilayers probed by XRMS SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article; Proceedings Paper CT 2nd International Conference on Synchrotron Radiation in Materials Science (SRMS-2) CY OCT 31-NOV 03, 1998 CL KOBE, JAPAN SP Japan Atomic Energy Res Inst, Inst Phys & Chem Res, Japan Synchrotron Radiat Res Inst DE magnetic scattering; magnetic profile; multilayers ID CIRCULAR-DICHROISM; RAY; SCATTERING; CE AB The element and electronic shelf specificities of x-ray resonant magnetic scattering have been used to investigate the induced magnetization of the 5d and 4f electronic states of Ce in a [Ce(10 Angstrom)/Fe(30 Angstrom)] x 100 multilayer. We show that the measurement of the magnetic contribution to the intensities diffracted at low angles at the L-2 and M-4 edge of the rare-earth allows to investigate the profile of the 5d and 4f magnetic polarisation across the rare-earth layer. The Ce 5d polarization is found to be oscillating across the Ce layer with a slow decrease from the interfaces with Fe towards the center of the layer. Preliminary results on the Ce 4f polarisation indicate a constant profile. C1 CNRS, Cristallog Lab, F-38042 Grenoble 9, France. Univ Grenoble 1, F-38042 Grenoble, France. Univ Gottingen, Inst Phys 1, D-37073 Gottingen, Germany. European Synchrotron Radiat Facil, F-38043 Grenoble, France. USN, Res Lab, Washington, DC 20375 USA. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. RP Seve, L (reprint author), CNRS, Cristallog Lab, BP 166, F-38042 Grenoble 9, France. RI Bartolome, Fernando/K-1700-2014 OI Bartolome, Fernando/0000-0002-0047-1772 NR 16 TC 1 Z9 1 U1 0 U2 0 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PY 1999 VL 38 SU 1 BP 385 EP 388 PG 4 WC Physics, Applied SC Physics GA 240AT UT WOS:000082804000095 ER PT J AU Glover, CJ Yu, KM Ridgway, MC Foran, GJ AF Glover, CJ Yu, KM Ridgway, MC Foran, GJ TI Characterisation of ion-implantation-induced disorder in GaAs by EXAFS SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article; Proceedings Paper CT 2nd International Conference on Synchrotron Radiation in Materials Science (SRMS-2) CY OCT 31-NOV 03, 1998 CL KOBE, JAPAN SP Japan Atomic Energy Res Inst, Inst Phys & Chem Res, Japan Synchrotron Radiat Res Inst DE GaAs; ion implantation; disorder; EXAFS ID ABSORPTION FINE-STRUCTURE; RAY ANOMALOUS SCATTERING; AMORPHOUS GAAS; PROGRAM AB The Ga and As local atomic environments in ion-implanted GaAs have been characterised with extended x-ray absorption fine structure spectroscopy. The accumulation of disorder prior to the onset of amorphisation has been investigated. For implantation at -188 degrees C, a heterogenous amorphisation process was identified and an increase in bondlength and Debye-Waller factor and a decrease in first-shell coordination number were observed. Analysis of the EXAFS data using the cumulant method revealed a monotonic increase in asymmetry in the interatomic distance distribution as a function of dose. Amorphised samples implanted to ion doses two orders of magnitude beyond the amorphisation threshold have also been studied and the structural parameters of amorphous GaAs were shown to be independent of implant conditions. C1 Australian Natl Univ, Res Sch Phys Sci & Engn, Canberra, ACT 2601, Australia. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. RP Glover, CJ (reprint author), Australian Natl Univ, Res Sch Phys Sci & Engn, Canberra, ACT 2601, Australia. 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 NR 19 TC 1 Z9 1 U1 0 U2 0 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PY 1999 VL 38 SU 1 BP 548 EP 551 PG 4 WC Physics, Applied SC Physics GA 240AT UT WOS:000082804000137 ER PT J AU Gog, T AF Gog, T TI Multiple-energy x-ray holography with atomic resolution SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article; Proceedings Paper CT 2nd International Conference on Synchrotron Radiation in Materials Science (SRMS-2) CY OCT 31-NOV 03, 1998 CL KOBE, JAPAN SP Japan Atomic Energy Res Inst, Inst Phys & Chem Res, Japan Synchrotron Radiat Res Inst DE x-ray holography; electron holography ID DIFFRACTION PATTERNS; PHOTOELECTRON HOLOGRAPHY; FLUORESCENCE HOLOGRAPHY; ELECTRON; SCATTERING; IMAGES AB Multiple-energy x-ray holography (MEXH) is a particular implementation of an x-ray holographic method capable of directly imaging atomic structures in the bulk, at surfaces and interfaces of solids. It utilizes an interference field generated by incident and scattered x-rays within the sample, then determines its strength at specific atomic sites from integral fluorescence yields. Scanning large portions of reciprocal space, a hologram is recorded, which can be converted to a real space image by Fourier transformation. Image aberrations that adversely affect results in single-energy techniques are successfully avoided in this novel multi-energy version. C1 Argonne Natl Lab, CMC, CAT, Adv Photon Source, Argonne, IL 60439 USA. RP Gog, T (reprint author), Argonne Natl Lab, CMC, CAT, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PY 1999 VL 38 SU 1 BP 620 EP 624 PG 5 WC Physics, Applied SC Physics GA 240AT UT WOS:000082804000154 ER PT S AU Chapin, SJ Cirne, W Feitelson, DG Jones, JP Leutenegger, ST Schwiegelshohn, U Smith, W Talby, D AF Chapin, SJ Cirne, W Feitelson, DG Jones, JP Leutenegger, ST Schwiegelshohn, U Smith, W Talby, D BE Feielson, DG Rudolph, L TI Benchmarks and standards for the evaluation of parallel job schedulers SO JOB SCHEDULING STRATEGIES FOR PARALLEL PROCESSING SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 5th Annual Workshop on Job Scheduling Strategies for Parallel Processing held in Conjunction with the IPPS/SPDP '99 Conference CY APR 16, 1999 CL SAN JUAN, PR SP IPPS, SPDP ID TRACE-DRIVEN SIMULATION; WORKLOAD CHARACTERIZATION; PROCESSOR ALLOCATION; SYSTEMS; METASYSTEMS; COMPUTER AB The evaluation of parallel job schedulers hinges on the workloads used. It is suggested that this be standardized, in terms of both format and content, so as to ease the evaluation and comparison of different systems. The question remains whether this can encompass both traditional parallel systems and metacomputing systems. This paper is based on a panel on this subject that was held at the workshop, and the ensuing discussion; its authors are both the panel members and participants from the audience. Naturally, not all of us agree with all the opinions expressed here... C1 Syracuse Univ, Dept Elect Engn & Comp Sci, Syracuse, NY 13244 USA. Univ Calif San Diego, Dept Comp Sci & Engn, La Jolla, CA 92093 USA. Hebrew Univ Jerusalem, Inst Comp Sci, IL-91904 Jerusalem, Israel. NASA, Ames Res Ctr, MRJ Technol Solut, Moffett Field, CA 94035 USA. Univ Denver, Dept Math & Comp Sci, Denver, CO 80208 USA. Univ Dortmund, Comp Engn Inst, D-44221 Dortmund, Germany. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Chapin, SJ (reprint author), Syracuse Univ, Dept Elect Engn & Comp Sci, Syracuse, NY 13244 USA. EM chapin@cs.virginia.edu; walfredo@cs.ucsd.edu; feit@cs.huji.ac.il; jjones@nas.nasa.gov; leut@cs.du.edu; uwe@ds.e-technik.uni-dortmund.de; wsmith@mcs.anl.gov; davidt@cs.huji.ac.il NR 63 TC 34 Z9 34 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-66676-1 J9 LECT NOTES COMPUT SC PY 1999 VL 1659 BP 67 EP 90 PG 24 WC Computer Science, Theory & Methods SC Computer Science GA BR52F UT WOS:000166710400004 ER PT S AU Smith, W Taylor, V Foster, I AF Smith, W Taylor, V Foster, I BE Feielson, DG Rudolph, L TI Using run-time predictions to estimate queue wait times and improve scheduler performance SO JOB SCHEDULING STRATEGIES FOR PARALLEL PROCESSING SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 5th Annual Workshop on Job Scheduling Strategies for Parallel Processing held in Conjunction with the IPPS/SPDP '99 Conference CY APR 16, 1999 CL SAN JUAN, PUERTO RICO SP IPPS, SPDP AB On many computers, a request to run a job is not serviced immediately but instead is placed in a queue and serviced only when resources are released by preceding jobs. In this paper, we build on runtime prediction techniques that we developed in previous research to explore two problems. The first problem is to predict how long applications will wait in a queue until they receive resources. We develop runtime estimates that result in more accurate wait-time predictions than other run-time prediction techniques. The second problem we investigate is improving scheduling performance. We use run-time predictions to improve the performance of the least-work-first and backfill scheduling algorithms. We find that using our run-time predictor results in lower mean wait times for the workloads with higher offered loads and for the backfill scheduling algorithm. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Northwestern Univ, Dept Elect & Comp Engn, Evanston, IL 60208 USA. RP Smith, W (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 47 Z9 48 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-66676-1 J9 LECT NOTES COMPUT SC PY 1999 VL 1659 BP 202 EP 219 PG 18 WC Computer Science, Theory & Methods SC Computer Science GA BR52F UT WOS:000166710400011 ER PT J AU Mataya, MC AF Mataya, MC TI Simulating microstructural evolution during the hot working of alloy 718 SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article ID AUSTENITIC STAINLESS-STEEL; STRENGTH; STRAIN AB The simulation of microstructural evolution during the primary breakdown of production-sized alloy 718 ingots and billets by radial forging was accomplished in the laboratory via multiple-stroke axial compression testing of cylindrical specimens. The dwell or hold time between strokes was varied to simulate the deformation-time history for three different locations along the radial-forging work piece: lead-end, mid-length, and tail-end positions. The microstructural evolution varied with simulated work piece position. Static, rather than dynamic, recrystallization was responsible for the observed grain-size refinement, and its repetitive occurrence during consecutive dwell periods resulted in the maintenance of a fine-grain microstructure during multiple-stroke deformation sequences. For comparison, the total plastic strain was also applied in a single-stroke test. The single- and multiple-stroke techniques gave differing microstructural results, indicating that multiple-stroke testing is necessary in modeling microstructural evolution during primary breakdown. C1 Colorado Sch Mines, Adv Steel Proc & Prod Res Ctr, Golden, CO 80401 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Mataya, MC (reprint author), Colorado Sch Mines, Adv Steel Proc & Prod Res Ctr, Golden, CO 80401 USA. NR 22 TC 6 Z9 6 U1 0 U2 5 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD JAN PY 1999 VL 51 IS 1 BP 18 EP 26 DI 10.1007/s11837-999-0006-x PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 157RZ UT WOS:000078076600003 ER PT J AU Kent, MS McNamara, WF Fein, DB Domeier, LA Wong, APY AF Kent, MS McNamara, WF Fein, DB Domeier, LA Wong, APY TI Water adsorption in interfacial silane layers by neutron reflection: 1. Silane finish on silicon wafers SO JOURNAL OF ADHESION LA English DT Article DE water adsorption; interfacial water; silane coupling agents; hygrothermal conditioning; interpenetration of resin and silane; neutron reflection; durability ID COUPLING AGENT AB The interaction of water with a common commercial glass cloth silane finish is explored by neutron reflection. The silane coating is applied to the oxide surfaces of polished silicon wafers. Detailed profiles of D2O within the similar to 80 Angstrom silane finish layers are measured after exposure for 48 hours to a saturated D2O atmosphere at either 22 degrees C or 80 degrees C. The nature of the interaction of D2O with the finish layer is probed by exposing the samples to vacuum following adsorption. In both samples, the profile of adsorbed D2O is composed of at least two distinct layers: a thin (< 30 Angstrom) D2O-rich layer adjacent to the interface, and the bulk of the film in which only a low level of D2O is present. The amount of adsorbed D2O is greater for the sample conditioned at 80 degrees C than for the sample conditioned at 22 degrees C. In addition, adsorbed D2O within the interfacial layer is removed more slowly during evacuation for the sample conditioned at 80 degrees C than for the sample conditioned at 22 degrees C. These latter two results are interpreted as indicating increased hydrolysis of siloxane bonds for the samples conditioned at 80 degrees C. Surprisingly, after several months in vacuum the remaining D2O redistributes within the layer, accumulating within a very thin layer at the interface in both samples. The nature of this redistribution is not understood. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Sandia Natl Labs, Livermore, CA 94551 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Kent, MS (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 26 Z9 26 U1 0 U2 5 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0021-8464 J9 J ADHESION JI J. Adhes. PY 1999 VL 69 IS 1-2 BP 121 EP 138 DI 10.1080/00218469908015922 PG 18 WC Engineering, Chemical; Materials Science, Multidisciplinary; Mechanics SC Engineering; Materials Science; Mechanics GA 188MW UT WOS:000079851600008 ER PT J AU Kent, MS McNamara, WF Baca, PM Wright, W Domeier, LA Wong, APY Wu, WL AF Kent, MS McNamara, WF Baca, PM Wright, W Domeier, LA Wong, APY Wu, WL TI Water adsorption in interfacial silane layers by neutron reflection: 2. Epoxy plus silane finish on silicon wafers SO JOURNAL OF ADHESION LA English DT Article DE water adsorption; interfacial water; silane coupling agents; hygrothermal conditioning; interpenetration of resin and silane; neutron reflection; durability AB The interaction of water with an interphase composed of a common commercial glass cloth silane finish and an epoxy resin is explored by neutron reflection. The silane finish was applied to the oxide surfaces of polished silicon wafers. The epoxy resin (diglycidyl ether of bisphenol A with dicyandiamide curing agent) was then roll-coated over the silane finish and cured. Profiles of D2O in the interphase were measured by neutron reflection after varying periods of exposure to air saturated with D2O at 22 degrees C and at 80 degrees C. A significant uptake of D2O into the interphase region is observed after exposure at 80 degrees C for 3 days. The D2O profile in the interphase can be described by a two-layer model composed of a thin (similar to 15 Angstrom) layer with similar to 50 vol% D2O next to the silicon oxide surface and a second layer corresponding to the remainder of the silane-epoxy mixed layer with a much lower D2O level. No excess D2O is detected (detection limit similar to 3%) in the interface region under the same conditions if the silane finish is not present. For samples conditioned at 22 degrees C, no D2O is detected in the silane interphase after exposure for 18 days, but a significant uptake is observed after exposure for 6 months. The profile in the latter case can again be described by a two-layer model with a thin D2O-rich layer near the silicon oxide surface. The nature of the interaction of D2O with the interphase is further probed by exposing samples to vacuum following humidity conditioning. After evacuation for similar to 1 month, near complete removal of interfacial water is observed for samples conditioned at 80 degrees C for 3 days and also at 22 degrees C for 6 months. These observations are interpreted in terms of a reversible chemical interaction (hydrolysis) between water and the silane finish. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Sandia Natl Labs, Livermore, CA 94551 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Kent, MS (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 8 TC 25 Z9 25 U1 0 U2 4 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0021-8464 J9 J ADHESION JI J. Adhes. PY 1999 VL 69 IS 1-2 BP 139 EP 163 DI 10.1080/00218469908015923 PG 25 WC Engineering, Chemical; Materials Science, Multidisciplinary; Mechanics SC Engineering; Materials Science; Mechanics GA 188MW UT WOS:000079851600009 ER PT J AU Netravali, AN Caceres, JM Thompson, MO Renk, TJ AF Netravali, AN Caceres, JM Thompson, MO Renk, TJ TI Surface modification of ultra-high strength polyethylene fibers for enhanced adhesion to epoxy resins using intense pulsed high-power ion beam SO JOURNAL OF ADHESION SCIENCE AND TECHNOLOGY LA English DT Article DE surface modification; ultra-high strength polyethylene fibers; intense pulsed high-power ion beam; adhesion; fiber/matrix interface; surface energy; wettability ID ALLYLAMINE PLASMA DEPOSITION; AMMONIA PLASMA; POLYMER DEPOSITION; FORMED POLYMERS; GRAPHITE FIBERS; UHSPE FIBERS; INTERFACE; PEEK AB The effects of intense pulsed high power ion beam (HPIB) treatment of ultra-high strength polyethylene (UHSPE) fibers on the fiber/epoxy resin interface strength were studied. For this study. argon ions were used to treat Spectra(TM) 1000 (UHSPE) fibers in vacuum. Chemical and topographical changes of the fiber surfaces were characterized using Fourier transform infrared spectroscopy in attenuated total reflectance mode (FTIR-ATR), X-ray photoelectron spectroscopy (XPS); dynamic wettability measurements, and scanning electron microscopy (SEM). The fiber/epoxy resin interfacial shear strength (IFSS) was evaluated by the single fiber pull-out test. The FTIR-ATR and XPS data indicate that oxygen was incorporated onto the fiber surface as a result of the HPIB treatment. The wettability data indicate that the fibers became more polar after HPIB treatment and also more wettable. Although the total surface energy increased only slightly after treatment, the dispersive component decreased significantly while the acid-base component increased by a similar amount. SEM photomicrographs revealed that the surface roughness of the fibers increased following the HPIB treatment. The single fiber pull-out test results indicate that HPIB treatment significantly improved the IFSS of UHSPE fibers with epoxy resin. This enhancement in IFSS is attributed to increased roughness of the fiber surface resulting in mechanical bonding and in increased interface area, increased polar nature and wettability, and an improvement in the acid-base component of the surface energy after the HPIB treatment. C1 Cornell Univ, Fiber Sci Program, Ithaca, NY 14853 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Netravali, AN (reprint author), Cornell Univ, Fiber Sci Program, Ithaca, NY 14853 USA. RI Caceres, Jose/M-2820-2014; OI Caceres, Jose/0000-0003-0426-0232; Thompson, Michael/0000-0002-4933-009X NR 26 TC 15 Z9 18 U1 1 U2 7 PU VSP BV PI ZEIST PA PO BOX 346, 3700 AH ZEIST, NETHERLANDS SN 0169-4243 J9 J ADHES SCI TECHNOL JI J. Adhes. Sci. Technol. PY 1999 VL 13 IS 11 BP 1331 EP 1342 DI 10.1163/156856199X00235 PG 12 WC Engineering, Chemical; Materials Science, Multidisciplinary; Mechanics SC Engineering; Materials Science; Mechanics GA 262FW UT WOS:000084055800007 ER PT J AU Ingber, MS Womble, DE Geller, AS Rader, DJ Mondy, LA AF Ingber, MS Womble, DE Geller, AS Rader, DJ Mondy, LA TI Boundary element method calculations of the mobility of nonspherical particles - 3. Parallel implementation for long chains SO JOURNAL OF AEROSOL SCIENCE LA English DT Article ID STOKES-FLOW AB A boundary element formulation for implementation on computers with massively parallel architecture, which allows calculation of particle drag and torque for particle agglomerates, is described. Shape factors for long, linear chains of spheres translating through a quiescent fluid are calculated. These calculations show that the correlation presented in an earlier paper (Geller et al., 1993), which was based on boundary element results for much shorter chains, continues to hold for chains of up to 700 constituent spheres; and, as expected, the slender body results, also presented by Geller and coworkers (1993), more closely agree with the numerical results for these longer chains. Published by Elsevier Science Ltd. All rights reserved. C1 Univ New Mexico, Dept Mech Engn, Albuquerque, NM 87131 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Mondy, LA (reprint author), Univ New Mexico, Dept Mech Engn, Albuquerque, NM 87131 USA. NR 5 TC 1 Z9 1 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0021-8502 J9 J AEROSOL SCI JI J. Aerosol. Sci. PD JAN PY 1999 VL 30 IS 1 BP 127 EP 130 DI 10.1016/S0021-8502(98)00028-7 PG 4 WC Engineering, Chemical; Engineering, Mechanical; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 133EY UT WOS:000076674700011 ER PT J AU Dobson, FS Risch, TS Murie, JO AF Dobson, FS Risch, TS Murie, JO TI Increasing returns in the life history of Columbian ground squirrels SO JOURNAL OF ANIMAL ECOLOGY LA English DT Review DE increasing returns; life history; path analysis; reproductive effort; Spermophilus ID NUTRIENT-RESERVE DYNAMICS; CLUTCH-SIZE; SEASONAL DECLINE; LITTER SIZE; BIRTH-DATE; REPRODUCTIVE SUCCESS; PATH-ANALYSIS; BODY-MASS; SPERMOPHILUS-COLUMBIANUS; TAMIASCIURUS-HUDSONICUS AB 1. We examined positive associations and trade-offs of maternal and reproductive traits in a population of Columbian ground squirrels, Spermophilus columbianus. 2. Structural size, body condition, mother's personal allocation to body mass during reproduction, and timing of littering were estimated for live-trapped reproductive females that were observed during an 8-year period, and were compared to litter mass, litter size, and average pup mass using path analyses. 3. Mothers exhibited age-structured traits that influenced reproductive patterns. Yearling mothers were significantly smaller, bred later, and had smaller litters than older females. Mothers that gained more body mass during reproduction and older mothers in good body condition that were structurally large had larger litters. 4. Early seasonal timing of littering was an important positive influence on successful reproduction by older mothers only in early breeding seasons and in years when conditions for reproduction were good for all females. 5. The number of offspring that survived to 1 year of age was most strongly associated with litter mass and litter size; date of breeding was of secondary influence, with earlier litters exhibiting greater success. 6. In general, mothers that gained the most in body mass during reproduction were concurrently more successful in weaning large litters (perhaps due to better quality of foraging habitat). 7. In addition to expected reproductive trade-offs, reproduction by Columbian ground squirrels exhibited positive associations of life-history traits that may reflect evolutionary increasing returns. C1 Auburn Univ, Dept Zool & Wildlife Sci, Auburn, AL 36849 USA. Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. Univ Alberta, Dept Biol Sci, Edmonton, AB T6G 2E9, Canada. RP Dobson, FS (reprint author), Auburn Univ, Dept Zool, Auburn, AL 36849 USA. RI Murie, Jan/F-3663-2014 NR 102 TC 68 Z9 71 U1 4 U2 17 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0021-8790 J9 J ANIM ECOL JI J. Anim. Ecol. PD JAN PY 1999 VL 68 IS 1 BP 73 EP 86 DI 10.1046/j.1365-2656.1999.00268.x PG 14 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA 186VG UT WOS:000079750400007 ER PT J AU Porch, W Borys, R Durkee, P Gasparovic, R Hooper, W Hindman, E Nielsen, K AF Porch, W Borys, R Durkee, P Gasparovic, R Hooper, W Hindman, E Nielsen, K TI Observations of ship tracks from ship-based platforms SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID CLOUDS AB Ship-based measurements in June 1994 provided information about ship-track clouds and associated atmospheric environment observed from below cloud levels that provide a perspective different from satellite and aircraft measurements. Surface measurements of latent and sensible heat fluxes, sea surface temperatures, and meteorological profiles with free and tethered balloons provided necessary input conditions for models of ship track formation and maintenance. Remote sensing measurements showed a coupling of ship plume dynamics and entrainment into overlaying clouds. Morphological and dynamic effects were observed on clouds unique to the ship tracks. These morphological changes included lower cloud bases early in the ship-track formation, evidence of raised cloud bases in more mature tracks, sometimes higher cloud tops, thin cloud-free regions paralleling the tracks, and often stronger radar returns. The ship-based lidar aerosol measurements revealed that ship plumes often interacted with the overlying clouds in an intermittent rather than continuous manner. These observations imply that more must be learned about ship-track dynamics before simple relations between cloud condensation nuclei and cloud brightness can be developed. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Nevada, Desert Res Inst, Ctr Atmospher Sci, Reno, NV 89506 USA. USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA. USN, Res Lab, Washington, DC 20375 USA. CUNY City Coll, Dept Earth & Atmospher Sci, New York, NY 10031 USA. RP Porch, W (reprint author), Univ Calif Los Alamos Natl Lab, D-407, Los Alamos, NM 87545 USA. EM wporch@lanl.gov NR 17 TC 8 Z9 8 U1 0 U2 3 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 JAN PY 1999 VL 38 IS 1 BP 69 EP 81 DI 10.1175/1520-0450(1999)038<0069:OOSTFS>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 157HC UT WOS:000078054700006 ER PT J AU Kuritz, T AF Kuritz, T TI Cyanobacteria as agents for the control of pollution by pesticides and chlorinated organic compounds SO JOURNAL OF APPLIED MICROBIOLOGY LA English DT Article; Proceedings Paper CT SfAM Symposium on Aquatic Microbiology CY JUL, 1998 CL UNIV LANCASTER, LANCASTER, ENGLAND HO UNIV LANCASTER ID FILAMENTOUS CYANOBACTERIA; ANACYSTIS-NIDULANS; RICE FIELDS; SHORT-TERM; HEXACHLOROCYCLOHEXANE; BIODEGRADATION; HERBICIDES; ECOSYSTEM; SOIL; DECHLORINATION AB Cyanobacteria are phototrophic aquatic micro-organisms that are found in a variety of environments, including polluted ones. Fifteen strains of cyanobacteria that belong to three taxonomic groups are able to degrade lindane (lambda-hexachlorocyclohexane, a recalcitrant pesticide). The initial degradation pathway has been studied in two filamentous nitrogen-fixing strains of Anabaena sp, PCC 7120 and Nostoc ellipsosporum. These cyanobacteria dechlorinated loindane first to pentachlorocyclohexene and then to a mixutre of trichlorobenzenes, and possibly further. Lindane dechlorination by these organisms occurred only in the presence of nitrate in the medium. Both ammonium and darkness inhibited the process. This combination of observations led us to the hypothesis that the nitrate-reduction system of cyanobacteria may be involved in dechlorination, The hypothesis was proven by the analysis of Anabaena sp. transpositional mutants in four genes of the nil operon, The mutants were unable to dechlorinate lindane. However, there was no correlation between lindane dechlorination and activities of individual proteins encoded by this operon. Genetic engineering of Anabaena sp. and N. ellipsosporum that introduced linA lindane dechlorination operon from Psuedomonas paucimobilis allowed us to uncouple dechlorination from nitrate requirement. Introduction, by genetic engineering, of fcABC (the 4-chlorobenzoate dechlorination system from Arthrobacter globiformis) to Anabaena sp, and N, ellipsosporum rendered these strains newly capable of 4-chlorobenzoate dechlorination both constitutively and inducible by an environmental factor. C1 Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37932 USA. RP Kuritz, T (reprint author), Oak Ridge Natl Lab, MS 6480,1060 Commerce Pk, Oak Ridge, TN 37830 USA. NR 49 TC 2 Z9 2 U1 0 U2 3 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 1364-5072 J9 J APPL MICROBIOL JI J. Appl. Microbiol. PY 1999 VL 85 SU S BP 186S EP 192S PG 7 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 208MM UT WOS:000080995200023 ER PT J AU Mattila, T Zunger, A AF Mattila, T Zunger, A TI Predicted bond length variation in wurtzite and zinc-blende InGaN and AlGaN alloys SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ABSORPTION FINE-STRUCTURE; RANDOM SOLID-SOLUTIONS; ATOMIC-SCALE STRUCTURE; SEMICONDUCTOR ALLOYS; LOCAL-STRUCTURE; TERNARY ALLOYS; GA1-XINXAS AB Valence force field simulations utilizing large supercells are used to investigate the bond lengths in wurtzite and zinc-blende InxGa1-xN and AlxGa1-xN random alloys. We find that (i) while the first-neighbor cation-anion shell is split into two distinct values in both wurtzite and zinc-blende alloys (RGa-N1 not equal RIn-N1), the second-neighbor cation-anion bonds are equal (RGa-N2 = RIn-N2). The second-neighbor cation-anion bonds exhibit a crucial difference between wurtzite and zinc-blende binary structures: in wurtzite we find two bond distances which differ in length by 13% while in the zinc-blende structure there is only one bond length. This splitting is preserved in the alloy, and acts as a fingerprint, distinguishing the wurtzite from the zinc-blende structure. (iii) The small splitting of the first-neighbor cation-anion bonds in the wurtzite structure due to nonideal c/a ratio is preserved in the alloy, but is obscured by the bond length broadening. (iv) The cation-cation bond lengths exhibit three distinct values in the alloy (Ga-Ga, Ga-In, and In-In), while the anion-anion bonds are split into two values corresponding to N-Ga-N and N-In-N. (v) The cation-related splitting of the bonds and alloy broadening are considerably larger in InGaN alloy than in AlGaN alloy due to larger mismatch between the binary compounds. (vi) The calculated first-neighbor cation-anion and cation-cation bond lengths in InxGa1-xN alloy are in good agreement with the available experimental data. The remaining bond lengths are provided as predictions. In particular, the predicted splitting for the second-neighbor cation-anion bonds in the wurtzite structure awaits experimental testing. (C) 1999 American Institute of Physics. [S0021-8979(99)09601-2]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Mattila, T (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Zunger, Alex/A-6733-2013 NR 22 TC 52 Z9 52 U1 3 U2 11 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 1 PY 1999 VL 85 IS 1 BP 160 EP 167 DI 10.1063/1.369463 PG 8 WC Physics, Applied SC Physics GA 148DM UT WOS:000077489200022 ER PT J AU Terry, J Linford, MR Wigren, C Cao, RY Pianetta, P Chidsey, CED AF Terry, J Linford, MR Wigren, C Cao, RY Pianetta, P Chidsey, CED TI Alkyl-terminated Si(111) surfaces: A high-resolution, core level photoelectron spectroscopy study SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID LANGMUIR-BLODGETT MONOLAYERS; CHEMICAL VAPOR-DEPOSITION; ELECTRONIC-STRUCTURE; SILICON SURFACES; DIETHYLSILANE; ORIENTATION; SI(100) AB The bonding of alkyl monolayers to Si(111) surfaces has been studied with high-resolution core level photoelectron spectroscopy (PES). Two very different wet-chemical methods have been used to prepare the alkyl monolayers: (i) Olefin insertion into the H-Si bond of the H-Si(111) surface, and (ii) replacement of Cl on the Cl-Si(111) surface by an alkyl group from an alkyllithium reagent. In both cases, PES has revealed a C 1s component shifted to lower binding energy and a Si 2p component shifted to higher binding energy. Both components are attributed to the presence of a C-Si bond at the interface. Along with photoelectron diffraction data [Appl. Phys. Lett. 71, 1056, (1997)], these data are used to show that these two synthetic methods can be used to functionalize the Si(111) surface. (C) 1999 American Institute of Physics. [S0021-8979(98)00324- 7]. C1 Stanford Univ, Dept Chem, Stanford, CA 94309 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Terry, J (reprint author), Stanford Univ, Dept Chem, Stanford, CA 94309 USA. NR 23 TC 158 Z9 158 U1 0 U2 17 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 1 PY 1999 VL 85 IS 1 BP 213 EP 221 DI 10.1063/1.369473 PG 9 WC Physics, Applied SC Physics GA 148DM UT WOS:000077489200030 ER PT J AU Main, C Zollondz, JH Reynolds, S Gao, W Bruggemann, R Rose, MJ AF Main, C Zollondz, JH Reynolds, S Gao, W Bruggemann, R Rose, MJ TI Investigation of collection efficiencies much larger than unity in a-Si : H p-i-n structures SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SCHOTTKY BARRIERS; GREATER AB An apparent quantum efficiency much larger than unity is observed under reverse bias voltage conditions, in hydrogenated amorphous silicon p-i-n structures. High collection efficiencies are measured for low-level probe illumination of the device n side with red light, with simultaneous bias illumination from the device p side with strongly absorbed blue light. The photogating effect responsible varies experimentally with reverse bias voltage, and collection efficiencies for the probe excitation of up to 50 are obtained. Detailed computer simulations corroborate such high values of quantum efficiency and the underlying mechanisms for the effect are revealed. We present the influence on quantum efficiency of bias light wavelength and photon flux, probe light photon flux, applied voltage, and defect density. (C) 1999 American Institute of Physics. [S0021-8979(99)01801-0]. C1 Univ Abertay Dundee, Sch Sci & Engn, Dundee DD1 1HG, Scotland. Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Oldenburg, Fachbereich Phys, D-26111 Oldenburg, Germany. Univ Dundee, Dept Appl Phys & Elect & Mfg Engn, Dundee DD1 4HN, Scotland. RP Main, C (reprint author), Univ Abertay Dundee, Sch Sci & Engn, Dundee DD1 1HG, Scotland. RI Reynolds, Steve/A-1583-2009 OI Reynolds, Steve/0000-0002-1514-6382 NR 12 TC 7 Z9 7 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 1 PY 1999 VL 85 IS 1 BP 296 EP 301 DI 10.1063/1.369444 PG 6 WC Physics, Applied SC Physics GA 148DM UT WOS:000077489200043 ER PT J AU Misra, A Hundley, MF Hristova, D Kung, H Mitchell, TE Nastasi, M Embury, JD AF Misra, A Hundley, MF Hristova, D Kung, H Mitchell, TE Nastasi, M Embury, JD TI Electrical resistivity of sputtered Cu/Cr multilayered thin films SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID POLYCRYSTALLINE CHROMIUM FILMS; CU; NB; COMPOSITES; RESISTANCE; STRENGTH; STRESS AB Parallel (in-plane) electrical resistivities of single-layered Cu and Cr films, and Cu/Cr multilayered thin films sputter deposited on Si substrates were evaluated as a function of layer thicknesses ranging from 2.5 to 150 nm in the temperature range of 4-325 K. The resistivity of the multilayers at a given temperature increased and residual resistivity ratio decreased with decreasing layer thicknesses. At 300 K, the resistivity of a 1 mu m thick Cu film was approximately equal to the bulk value, but the resistivity of the Cr film was an order of magnitude higher than that of bulk Cr. The microstructures of the multilayers and the single-layered Cu and Cr thin films were characterized by transmission electron microscopy. For layer thicknesses ranging from 2.5 to 150 nm, the multilayers exhibited sharp, planar interfaces between the two phases. The individual Cu and Cr layers were nanocrystalline with near-equiaxed grains in Cu and columnar grains in Cr. The dependence of electrical resistivity on the layer thickness of multilayers is explained using a model that accounts for interface scattering and thin-film resistivities of polycrystalline Cu and Cr. (C) 1999 American Institute of Physics. [S0021-8979(99)06201-5]. 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 24 TC 20 Z9 21 U1 0 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 1 PY 1999 VL 85 IS 1 BP 302 EP 309 DI 10.1063/1.369446 PG 8 WC Physics, Applied SC Physics GA 148DM UT WOS:000077489200044 ER PT J AU von Rottkay, K Rubin, M Duine, PA AF von Rottkay, K Rubin, M Duine, PA TI Refractive index changes of Pd-coated magnesium lanthanide switchable mirrors upon hydrogen insertion SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB The optical effect upon insertion of hydrogen into Pd-coated magnesium lanthanide switchable mirrors is investigated in terms of the changes of their complex refractive indices. A significant change in the optical constants of LnMg layers is seen between the as-deposited state and the dehydrided state after one cycle. Furthermore, the optical effect of switching the Pd cap layer to a PdH cap layer was determined. It is shown that the Pd layer mainly limits the visible transmittance of the hydrided stack to about 35%-40%. Whereas the extinction coefficient of dehydrided LnMg layers at 550 nm is between 2.2 and 3.1, it is as low as 10(-4) in the transparent state. This is of great promise to applications requiring large optical contrast (e. g., optical switches). (C) 1999 American Institute of Physics. [S0021-8979(99)05101- 4]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Philips Res Labs, NL-5656 AA Eindhoven, Netherlands. RP von Rottkay, K (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 8 TC 74 Z9 74 U1 2 U2 17 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 1 PY 1999 VL 85 IS 1 BP 408 EP 413 DI 10.1063/1.369399 PG 6 WC Physics, Applied SC Physics GA 148DM UT WOS:000077489200062 ER PT J AU Bullock, AB Bolton, PR AF Bullock, AB Bolton, PR TI Laser-induced back ablation of aluminum thin films using picosecond laser pulses SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID METAL; DEPOSITION; TARGETS AB A study of laser-induced back ablation of aluminum thin film targets with picosecond laser pulses is reported. Ablated plume edge velocities are studied as a function of film thickness, laser pulse width, and incident laser fluence. Edge velocity results are compared to a model of total transmitted fluence incident at the substrate/film interface. A model including laser-induced avalanche ionization and multiphoton ionization mechanisms in the substrate shows a transmitted fluence limit which is consistent with observed edge velocity limits. (C) 1999 American Institute of Physics. [S0021-8979(98)01824- 6]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Bullock, AB (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 13 TC 50 Z9 50 U1 1 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 1 PY 1999 VL 85 IS 1 BP 460 EP 465 DI 10.1063/1.369393 PG 6 WC Physics, Applied SC Physics GA 148DM UT WOS:000077489200071 ER PT J AU Heffelfinger, JR Medlin, DL McCarty, KF AF Heffelfinger, JR Medlin, DL McCarty, KF TI On the initial stages of AlN thin-film growth onto, 0001 oriented Al2O3 substrates by molecular beam epitaxy SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ALUMINUM NITRIDE; LOW-TEMPERATURE; BUFFER LAYER; SAPPHIRE; SURFACE; SUBLIMATION; DIFFRACTION; ALPHA-AL2O3; MORPHOLOGY; DEPOSITION AB Conventional and high-resolution transmission electron microscopy are used to characterize the initial stages of AlN thin-film growth. AlN films are deposited by molecular beam epitaxy onto annealed (0001) oriented alpha-Al2O3 (sapphire) substrates. During the initial stages of film growth (film thickness similar to 25 nm) AlN forms islands of varying alignment with the Al2O3 substrate. Some of the AlN islands are well aligned with the [11 (2) over bar 0]Aln parallel to[10 (1) over bar 0] Al2O3 and (0001) AlN parallel to(0001)Al2O3, which matches closed- packed planes and directions. Other islands exhibit either an alignment of one set of planes, i.e., grains are aligned with the (11 (0) over bar 1)AlN parallel to(11 (2) over bar 0) Al2O3, or are misaligned with respect to the Al2O3 substrate. As the AlN film grows in thickness (film thickness similar to 100 nm), the film becomes continuous, and the closed- packed planes and directions of the film and substrate are aligned for the majority of the film. Islands of AlN with an alignment other than this predominant orientation disturb the growth near the AlN/Al2O3 interface and create displacements along the [0001] AlN direction in overlying AlN grains. These misaligned AlN grains provide one source for the formation of planar defects in the epitaxial AlN films. The evolution of the AlN film microstructure and the reasons for the observed orientation relationships are discussed. (C) 1999 American Institute of Physics. [S0021-8979(99)00701-X]. C1 Sandia Natl Labs, Ctr Mat Sci & Engn, Livermore, CA 94551 USA. RP Heffelfinger, JR (reprint author), Hutchinson Technol, 40 W Highland Pk, Hutchinson, MN 55350 USA. EM doug-medlin@sandia.gov RI McCarty, Kevin/F-9368-2012 OI McCarty, Kevin/0000-0002-8601-079X NR 26 TC 26 Z9 27 U1 1 U2 14 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 1 PY 1999 VL 85 IS 1 BP 466 EP 472 DI 10.1063/1.369409 PG 7 WC Physics, Applied SC Physics GA 148DM UT WOS:000077489200072 ER PT J AU Falkenstein, Z AF Falkenstein, Z TI Effects of the O-2 concentration on the removal efficiency of volatile organic compounds with dielectric barrier discharges in Ar and N-2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SILENT-DISCHARGE; ATMOSPHERIC CHEMISTRY; PHOTOCHEMICAL DATA; GENERATION; PLASMAS; ULTRAVIOLET; MIXTURES; OXYGEN AB This article presents experimental results on the effects of the O-2 concentration on the removal efficiency of two exemplaric volatile organic compounds (VOCs): toluene (TOL) and trichloroethylene (TCE), with dielectric barrier discharges in dry Ar and N-2. For both carrier gases, there is an optimal oxygen concentration of 0.3% for the removal efficiency, suggesting optimal utilization of oxygen radicals for VOC attack, rather than ozone production which has slow reaction rates with TOL and TCE. This is manifested by measurements of ozone concentrations in mixtures of Ar/O-2/TCE as a function of the oxygen concentration, showing a minimum at maximal removal efficiencies. All results are discussed in terms of changes in the discharge behavior, radical formation, and chemical reaction pathways with changing O-2 concentration in the carrier gas. (C) 1999 American Institute of Physics. [S0021-8979(99)09001-5]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Falkenstein, Z (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM falkenstein@lanl.gov NR 33 TC 36 Z9 38 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 1 PY 1999 VL 85 IS 1 BP 525 EP 529 DI 10.1063/1.369484 PG 5 WC Physics, Applied SC Physics GA 148DM UT WOS:000077489200082 ER PT J AU Michalsky, J Dutton, E Rubes, M Nelson, D Stoffel, T Wesley, M Splitt, M DeLuisi, J AF Michalsky, J Dutton, E Rubes, M Nelson, D Stoffel, T Wesley, M Splitt, M DeLuisi, J TI Optimal measurement of surface shortwave irradiance using current instrumentation SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID RADIATIVE FLUXES; SATELLITE; CLOUDS; MODEL AB Although most measurements of total downwelling shortwave irradiance are made with pyranometers, the World Climate Research Program's Baseline Surface Radiation Network has recommended the use of the summation of shortwave components in which the direct normal irradiance is measured and multiplied by the cosine of the solar zenith angle and then added to the diffuse horizontal irradiance measured by a pyranometer that is shaded from direct solar radiation by a disk. The nonideal angular response of most pyranometers limits their accuracy to about 3%, or 20-30 W m(-2), for instantaneous clear-sky measurements. An intensive study of 21 separate measurements of total horizontal irradiance was conducted during extreme winter conditions of low sun and cold temperatures over 12 days at the National Oceanic and Atmospheric Administration's Climate Monitoring and Diagnostics Laboratory. The experiment showed that the component sum methodology could lower the uncertainty by a factor of 2 or 3. A clear demonstration of this improvement was realized in a separate experiment conducted at the Atmospheric Radiation Measurement Southern Great Plains Cloud and Radiation Testbed site during April 1996. Four independent measurements of downwelling shortwave irradiance using the component sum technique showed typical differences at solar noon of about 10 W m(-2). The mean of these summed measurements at solar noon was lower than the mean of the most-well-calibrated pyranometer measurements, acquired simultaneously, by about 30 W m(-2), which is consistent with the typical angular response of many pyranometers. C1 SUNY Albany, Atmospher Sci Res Ctr, Univ Albany, Albany, NY 12203 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. Cooperat Inst Res Environm Studies, Boulder, CO USA. Natl Renewable Energy Lab, Golden, CO USA. Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. Univ Oklahoma, Cooperat Inst Mesoscale Meteorol Studies, Norman, OK 73019 USA. NOAA, Surface Radiat Res Branch, Boulder, CO USA. RP Michalsky, J (reprint author), SUNY Albany, Atmospher Sci Res Ctr, Univ Albany, 251 Fuller Rd, Albany, NY 12203 USA. OI Splitt, Michael/0000-0002-7690-5100 NR 17 TC 48 Z9 48 U1 1 U2 6 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 JAN PY 1999 VL 16 IS 1 BP 55 EP 69 DI 10.1175/1520-0426(1999)016<0055:OMOSSI>2.0.CO;2 PG 15 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 160YU UT WOS:000078261600005 ER PT J AU Wos, L Pieper, GW AF Wos, L Pieper, GW TI The hot list strategy SO JOURNAL OF AUTOMATED REASONING LA English DT Article DE automated reasoning programs; hot list strategy; OTTER ID RESONANCE AB Experimentation strongly suggests that, for attacking deep questions and hard problems with the assistance of an automated reasoning program, the more effective paradigms rely on the retention of deduced information. A significant obstacle ordinarily presented by such a paradigm is the deduction and retention of one or more needed conclusions whose complexity sharply delays their consideration. To mitigate the severity of the cited obstacle, I formulated and feature in this article the hat list strategy The hot list strategy asks the researcher to choose, usually from among the input statements characterizing the problem under study, one or more statements that are conjectured to play a key role for assignment completion. The chosen statements - conjectured to merit revisiting, again and again - are placed in an input list of statements, called the hot list. When an automated reasoning program has decided to retain a new conclusion C - before any other statement is chosen to initiate conclusion drawing - the presence of a nonempty hot list (with an appropriate assignment of the input parameter known as heat) causes each inference rule in use to be applied to C together with the appropriate number of members of the hot list. Members of the hot list are used to complete applications of inference rules and not to initiate applications. The use of the hot list strategy thus enables an automated reasoning program to briefly consider a newly retained conclusion whose complexity would otherwise prevent its use for perhaps many CPU-hours. To give evidence of the value of the strategy, I focus on four contexts: (1) dramatically reducing the CPU time required to reach a desired goal, (2) finding a proof of a theorem that had previously resisted all but the more inventive automated attempts, (3) discovering a proof that is more elegant than previously known, and (4) answering a question that had steadfastly eluded researchers relying on an automated reasoning program. I also discuss a related strategy, the dynamic hat list strategy (formulated by my colleague W McCune), that enables the program during a run to augment the contents of the hot list. In the Appendix, I give useful input files and interesting proofs. Because of frequent requests to do so, I include challenge problems to consider, commentary on my approach to experimentation and research, and suggestions to guide one in the use of McCune's automated reasoning program OTTER. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. EM wos@mcs.anl.gov; pieper@mcs.anl.gov NR 26 TC 5 Z9 5 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0168-7433 J9 J AUTOM REASONING JI J. Autom. Reasoning PD JAN PY 1999 VL 22 IS 1 BP 1 EP 44 DI 10.1023/A:1005909914693 PG 44 WC Computer Science, Artificial Intelligence SC Computer Science GA 170HV UT WOS:000078801000001 ER PT J AU Markillie, LM Varnum, SM Hradecky, P Wong, KK AF Markillie, LM Varnum, SM Hradecky, P Wong, KK TI Targeted mutagenesis by duplication insertion in the radioresistant bacterium Deinococcus radiodurans: Radiation sensitivities of catalase (katA) and superoxide dismutase (sodA) mutants SO JOURNAL OF BACTERIOLOGY LA English DT Article ID EXTREME RADIORESISTANCE; IONIZING-RADIATION; GENE DISRUPTION; REPAIR; DNA; RESISTANCE; INDUCTION; PATHWAYS AB Deinococcus radiodurans R1 is extremely resistant to both oxidative stress and ionizing radiation. A simple and general targeted mutagenesis method was developed to generate catalase (katA) and superoxide dismutase (sodA) mutants. Both mutants were shown to be more sensitive to ionizing radiation than the wild type. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Wong, KK (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. OI Wong, Kwong-Kwok/0000-0002-0375-6669 NR 25 TC 92 Z9 98 U1 0 U2 4 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 JAN PY 1999 VL 181 IS 2 BP 666 EP 669 PG 4 WC Microbiology SC Microbiology GA 157BX UT WOS:000078040200041 PM 9882685 ER PT J AU Mingaleev, SF Christiansen, PL Gaididei, YB Johansson, M Rasmussen, KO AF Mingaleev, SF Christiansen, PL Gaididei, YB Johansson, M Rasmussen, KO TI Models for energy and charge transport and storage in biomolecules SO JOURNAL OF BIOLOGICAL PHYSICS LA English DT Article DE bistability; long-range dispersion; bound state; anharmonic; nonlocal; soliton ID NONLINEAR MODEL; DNA DENATURATION; MOLECULAR CHAINS; ANHARMONIC LATTICES; SOLITON DYNAMICS; WAVE PROPAGATION; LOCALIZED MODES; EXCITATIONS; DISPERSION; MECHANISMS AB Two models for energy and charge transport and storage in biomolecules are considered. A model based on the discrete nonlinear Schrodinger equation with long-range dispersive interactions (LRI's) between base pairs of DNA is offered for the description of nonlinear dynamics of the DNA molecule. We show that LRI's are responsible for the existence of an interval of bistability where two stable stationary states, a narrow, pinned state and a broad, mobile state, coexist at each value of the total energy. The possibility of controlled switching between pinned and mobile states is demonstrated. The mechanism could be important for controlling energy storage and transport in DNA molecules. Another model is offered for the description of nonlinear excitations in proteins and other anharmonic biomolecules. We show that in the highly anharmonic systems a bound state of Davydov and Boussinesq solitons can exist. C1 Bogolyubov Inst Theoret Phys, UA-252143 Kiev, Ukraine. Tech Univ Denmark, Dept Math Modelling, DK-2800 Lyngby, Denmark. Linkoping Univ, Dept Phys & Measurement Technol, S-58183 Linkoping, Sweden. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Rasmussen, Kim/B-5464-2009; Christiansen, Peter /A-7978-2011; Johansson, Magnus/G-7097-2011 OI Rasmussen, Kim/0000-0002-4029-4723; Christiansen, Peter /0000-0002-1465-9987; Johansson, Magnus/0000-0001-6708-1560 NR 50 TC 51 Z9 51 U1 0 U2 5 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0092-0606 J9 J BIOL PHYS JI J. Biol. Phys. PY 1999 VL 25 IS 1 BP 41 EP 63 DI 10.1023/A:1005152704984 PG 23 WC Biophysics SC Biophysics GA 211XG UT WOS:000081186700004 PM 23345687 ER PT J AU Liu, Q Shen, BH Chen, DJ Chen, Y AF Liu, Q Shen, BH Chen, DJ Chen, Y TI Letter to the Editor: Backbone resonance assignments of human UBC9 SO JOURNAL OF BIOMOLECULAR NMR LA English DT Letter DE UBC9; heteronuclear NMR; resonance assignments; ubiquitination ID UBIQUITIN-CONJUGATING ENZYME; CRYSTAL-STRUCTURE; SYSTEM; PROTEINS C1 Univ Calif Los Alamos Natl Lab, Div Life Sci, DNA Damage & Repair Grp, Los Alamos, NM 87545 USA. City Hope Natl Med Ctr, Beckman Res Inst, Dept Cell & Tumor Biol, Duarte, CA 91010 USA. RP Chen, DJ (reprint author), Univ Calif Los Alamos Natl Lab, Div Life Sci, DNA Damage & Repair Grp, Los Alamos, NM 87545 USA. FU NIGMS NIH HHS [GM54190] NR 10 TC 7 Z9 7 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0925-2738 J9 J BIOMOL NMR JI J. Biomol. NMR PD JAN PY 1999 VL 13 IS 1 BP 89 EP 90 DI 10.1023/A:1008364314328 PG 2 WC Biochemistry & Molecular Biology; Spectroscopy SC Biochemistry & Molecular Biology; Spectroscopy GA 170JK UT WOS:000078802400012 PM 10070749 ER PT J AU Budinger, T Berson, A McVeigh, E Pettigrew, R Pohost, G Watson, J Wickline, S AF Budinger, T Berson, A McVeigh, E Pettigrew, R Pohost, G Watson, J Wickline, S TI Magnetic resonance imaging of the cardiovascular system (Reprinted from Radiology, vol 208, pg 573-576, 1998) SO JOURNAL OF CARDIOVASCULAR MAGNETIC RESONANCE LA English DT Reprint C1 NHLBI, NIH, Bethesda, MD 20892 USA. Univ Calif Berkeley, Lawrence Natl Berkeley Lab, Berkeley, CA 94720 USA. Johns Hopkins Univ, Baltimore, MD USA. Emory Univ, Atlanta, GA 30322 USA. Univ Alabama, Birmingham, AL USA. Jewish Hosp, St Louis, MO USA. RP Berson, A (reprint author), NHLBI, NIH, Bldg 10, Bethesda, MD 20892 USA. NR 1 TC 8 Z9 8 U1 0 U2 0 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 1097-6647 J9 J CARDIOV MAGN RESON JI J. Cardiov. Magn. Reson. PY 1999 VL 1 IS 1 BP 53 EP 58 DI 10.3109/10976649909080834 PG 6 WC Cardiac & Cardiovascular Systems; Radiology, Nuclear Medicine & Medical Imaging SC Cardiovascular System & Cardiology; Radiology, Nuclear Medicine & Medical Imaging GA 278CQ UT WOS:000084970700009 ER PT J AU Nandagopal, K Terzaghi-Howe, M Niyogi, SK AF Nandagopal, K Terzaghi-Howe, M Niyogi, SK TI Receptor recognition by histidine 16 of human epidermal growth factor via hydrogen-bond donor/acceptor interactions SO JOURNAL OF CELLULAR BIOCHEMISTRY LA English DT Article DE cell proliferation; ligand receptor interaction; protein engineering; rational design; tyrosine kinase ID SITE-DIRECTED MUTAGENESIS; FACTOR EGF MUTANT; FACTOR-ALPHA; TGF-ALPHA; KINASE-ACTIVITY; BINDING; RESIDUES; EXPRESSION; AFFINITY; EXCHANGE AB Human epidermal growth factor (hEGF) and human transforming growth factor alpha (hTGF alpha) are prototypical of structurally related polypeptide mitogens which interact with the epidermal growth factor receptor (EGFR). Several determinants of receptor recognition that specify function have been proposed on the basis of structural criteria. This study evaluates the role of one such candidate, H16 of hEGF, by site-specific mutagenesis. When assayed for receptor tyrosine kinase stimulation using (Glu(4),Tyr(1))(n) as the exogenous substrate in vitro, the relative agonist activities of position 16 mutants range from 14-263% of wild-type hEGF. The rank order of potency was round to correlate with the relative receptor binding affinities of the mutants, which range from 7-272% of wild-type, as determined by radioreceptor competition assays. The mitogenic activity of the H16 mutants is similar to that of wild-type hEGF as determined by clonogenic assays using rat tracheal epithelial cells. While the colony forming efficiencies do not reflect significant differences in growth rate or survival characteristics in the presence of the hEGF variants, it is reduced to 1.6% in control cultures which lack EGF in the medium. The results show that H16 of hEGF, although not essential for mitogenic activity, optimizes receptor recognition by hydrogen-bond donor/acceptor interactions and may share this feature with H18 of hTGF alpha. J. Cell. Biochem, 72:16-24, 1999. (C) 1998 Wiley-Liss, Inc. C1 Univ Tennessee, Oak Ridge Grad Sch Biomed Sci, Div Life Sci, Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Prot Engn & Mol Mutagenesis Program, Oak Ridge, TN 37831 USA. RP Niyogi, SK (reprint author), Univ Tennessee, Oak Ridge Grad Sch Biomed Sci, Div Life Sci, Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. EM niyogisk@bio.ornl.gov NR 49 TC 4 Z9 4 U1 0 U2 4 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0730-2312 J9 J CELL BIOCHEM JI J. Cell. Biochem. PD JAN 1 PY 1999 VL 72 IS 1 BP 16 EP 24 DI 10.1002/(SICI)1097-4644(19990101)72:1<16::AID-JCB3>3.0.CO;2-X PG 9 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 141NX UT WOS:000077151000003 PM 10025663 ER PT J AU Cabarcos, OM Weinheimer, CJ Lisy, JM Xantheas, SS AF Cabarcos, OM Weinheimer, CJ Lisy, JM Xantheas, SS TI Microscopic hydration of the fluoride anion SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID N = 1-4; WATER CLUSTERS; AB-INITIO; MOLECULAR COMPLEXES; BINDING-ENERGIES; ION COMPLEXES; LIQUID WATER; BASIS-SETS; SPECTROSCOPY; SOLVATION AB A combined experimental and theoretical investigation of the step-wise hydration of the fluoride ion has been performed in order to characterize the details of its solvation at the microscopic level. The comparable anion-water and water-water interactions pose a challenging experimental/theoretical problem due to competing intermolecular forces in these small ionic clusters. Vibrational spectra of size-selected F-(H2O)(3-5) in the O-H stretching region, coupled with high level ab initio calculations, have been used to analyze the spectra and assign the structures of these species. The interaction between the fluoride anion and water plays the dominant role, resulting in internally solvated clusters. The microhydration of fluoride ion is thus qualitatively different from the other halide ions. (C) 1999 American Institute of Physics. [S0021-9606(99)04501-8]. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Illinois, Dept Chem, Urbana, IL 61801 USA. RP Lisy, JM (reprint author), Univ Illinois, Dept Chem, 1209 W Calif St, Urbana, IL 61801 USA. EM j-lisy@uiuc.edu; sotiris.xantheas@pnl.gov RI Cabarcos, Orlando/B-3795-2009; Xantheas, Sotiris/L-1239-2015; OI Xantheas, Sotiris/0000-0002-6303-1037 NR 40 TC 163 Z9 163 U1 2 U2 20 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 JAN 1 PY 1999 VL 110 IS 1 BP 5 EP 8 DI 10.1063/1.478075 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 151AC UT WOS:000077697900002 ER PT J AU Baranyai, A Cummings, PT AF Baranyai, A Cummings, PT TI Steady state simulation of planar elongation flow by nonequilibrium molecular dynamics SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SHEAR-FREE FLOWS; VISCOSITIES; FLUIDS AB We present a novel method for performing steady state nonequilibrium molecular dynamics simulation of planar elongation flow based on the studies of Kraynik and Reinelt [Int. J. Multiphase Flow 18, 1045 (1992)]. These authors identified the orientation of the unit cell which leads to periodic behavior of the square lattice with the minimum period. This way the exponential deformation of the system periodically returns to a state where replacing some of the original particles with their images the initial state boundaries are recovered. We adopted their theoretical results to nonequilibrium molecular dynamics simulations and performed representative calculations for simple fluids. The new method solves the long-standing problem of simulating planar elongation flow in the steady state. (C) 1999 American Institute of Physics. [S0021-9606(99)51901-6]. 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 Baranyai, A (reprint author), Eotvos Lorand Univ, Dept Theoret Chem, POB 32, H-1518 Budapest 112, Hungary. RI Cummings, Peter/B-8762-2013 OI Cummings, Peter/0000-0002-9766-2216 NR 15 TC 38 Z9 38 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 1 PY 1999 VL 110 IS 1 BP 42 EP 45 DI 10.1063/1.478082 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 151AC UT WOS:000077697900009 ER PT J AU Skurski, P Gutowski, M Simons, J AF Skurski, P Gutowski, M Simons, J TI Theoretical study of the dipole-bound anion (HPPH3)(-) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ABINITIO ELECTRONIC-STRUCTURE; AB-INITIO; STATES; ENERGIES; DIPHOSPHINE; NITROMETHANE; ENERGETICS; STABILITY; MOLECULES; COMPLEXES AB The possibility of electron binding to the HPPH3 and H2PPH2 tautomers of diphosphine was studied at the coupled cluster level of theory with single, double, and noniterative triple excitations. The HPPH3 tautomer, with a dipole moment of 3.7 D, binds an electron by 333 cm(-1), whereas the H2PPH2 tautomer forms neither a dipole- nor valence-bound anionic state. It is suggested that the HPPH3 tautomer, which is kinetically stable but thermodynamically unstable relative to H2PPH2, may be formed by photodetachment from the P2H4- species examined in this work. An unusual aspect of the (HPPH3)(-) anion is that electron correlation contributes 82% to the electronic stability and effects beyond the fourth order of the Moller-Plesset perturbation theory contribute 55%. (C) 1999 American Institute of Physics. [S0021-9606(99)31201-0]. C1 Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA. Univ Gdansk, Dept Chem, PL-80952 Gdansk, Poland. Pacific NW Lab, Condensed Matter Theory Grp, Richland, WA 99352 USA. RP Simons, J (reprint author), Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA. NR 58 TC 35 Z9 35 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 1 PY 1999 VL 110 IS 1 BP 274 EP 280 DI 10.1063/1.478062 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 151AC UT WOS:000077697900036 ER PT J AU Evans, M Stimson, S Ng, CY Hsu, CW Jarvis, GK AF Evans, M Stimson, S Ng, CY Hsu, CW Jarvis, GK TI Rotationally resolved pulsed field ionization photoelectron study of O-2(+)(B-2 Sigma(-)(g), (2)Sigma(-)(u); v(+) = 0-7) at 20.2-21.3 eV SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HIGH-RESOLUTION THRESHOLD; CONFIGURATION-INTERACTION CALCULATIONS; ADVANCED LIGHT-SOURCE; SYNCHROTRON-RADIATION; PHOTOION COINCIDENCE; CHEMICAL-DYNAMICS; MOLECULAR-OXYGEN; SPECTROSCOPY; DISSOCIATION; STATES AB We have obtained rotationally resolved pulsed field ionization photoelectron (PFI-PE) spectra of O2 in the energy range of 20.2-21.3 eV, covering the ionization transitions of O2+(B 2Sigmag-, upsilon+ = 0-7, N+) <-- O2(X 3Sigmag-, upsilon " = 0, N "). Only the Delta N = -2, 0, and +2 (or O, Q, and S) rotational branches are observed in the PFI-PE bands for O2+(B 2Sigmag-, upsilon+ = 0-7), indicating that the outgoing electron continuum channels with angular momenta l = 1 and 3 dominate in the ionization transitions. This experiment allows the determination of accurate spectroscopic constants, such as ionization energy (20.29825 +/- 0.0004 eV) for the formation of O2+[B 2Sigmag-, upsilon+ = 0, N+ = 1 (F2)] from O2(X 3Sigmag-, upsilon " = 0, N " = 1), vibrational constants (omegae+ = 1152.91 cm-1, omegae+chie+ = 20.97 cm-1_, and rotational constants (Be+ = 1.255 +/- 0.0015 cm-1, alphae+ = 0.0241 +/- 0.00037 cm-1_ for O2+(B 2Sigmag-, upsilon+ = 0-6) are measured to be approximate to 0.2-0.6 mu s, which are significantly shorter than those of approximate to 1.9 mu s observed for O2+(b 4Sigmag-, upsilon+ = 0-5). The shorter (nominal) effective lifetimes for high-n Rydberg states converging to O2+(B 2Sigmag-, upsilon+ = 0-6) are attributed to the higher kinetic energy releases (or velocities) of O++O fragments resulting from predissociation of the O2+(B 2Sigmag-, upsilon+ = 0-6) ion cores. Rotationally resolved PFI-PE measurements also make possible the identification of the weak vibrational progression with the origin at 20.35 eV as associated with transitions to O2+(2Sigmau-, upsilon+ = 0-7). The analysis of the rotationally resolved PFI-PE bands for O2+(2Sigmau-, upsilon+ = 0 and 1) has yielded accurate rotational constants and IE values for these states. The rotational structures resolved in the O2+(2Sigmau-, upsilon+ = 0 and 1) PFI-PE bands are contributed overwhelmingly by the Delta N = -3, -1, +1, and +3 (or N, P, R, and T) rotational branches, showing that the angular momenta for the outgoing photoelectron are restricted to l = 0, 2, and 4. Based on simulation of the observed rotational structures, we also obtain the predissociative lifetimes for O2+(B 2Sigmag-, upsilon+ = 0-7) and O2+(2Sigmau-, upsilon+ = 0-7) and O2+(2Sigmau-, upsilon+ = 0-1) to be in the range of 0.45-2 ps. (C) 1999 American Institute of Physics. [S0021-9606(99)00801-6]. C1 Iowa State Univ Sci & Technol, Ames Lab, US DOE, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Ng, CY (reprint author), Iowa State Univ Sci & Technol, Ames Lab, US DOE, Ames, IA 50011 USA. EM CYNG@AMESLAB.GOV NR 39 TC 34 Z9 34 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 1 PY 1999 VL 110 IS 1 BP 315 EP 327 DI 10.1063/1.477915 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 151AC UT WOS:000077697900041 ER PT J AU Kliner, DAV Farrow, RL AF Kliner, DAV Farrow, RL TI Measurements of ground-state OH rotational energy-transfer rates SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID COLLISIONS; H-2; RELAXATION; HE; PROPENSITIES; TRANSITIONS; POPULATION; MECHANISM; RESONANCE; A2-SIGMA+ AB We have studied rotational energy transfer (RET) in collisions of OH with the bath gases Ar, N-2, O-2, and H2O at 293 K. Rotationally hot OH(X (2)Pi(3/2), upsilon "=0, N "=1-12) was generated by photolysis of H2O2 at 266 nm, and collisional relaxation of the nascent rotational distribution was monitored by laser-induced fluorescence. The data are remarkably well described by an exponential-gap model for the matrix of state-to-state RET rate constants. For Ar, N-2, and O-2, RET rates are significantly faster at low N " than high N "; for H2O, RET is approximately an order of magnitude faster than for the other bath gases, and the rate is not as strongly dependent on N ". The rates of rotationally inelastic energy transfer are similar in the X and A states, but the X-state depopulation rate constants (including nearly elastic, h-doublet-changing collisions) are faster than the A-state values. By comparing the depopulation rates derived from the present experiment with previous linewidth measurements, we conclude that RET is the dominant source of pressure broadening for OH microwave transitions and makes a significant contribution for ultraviolet A-X transitions. While generally good agreement is found between the present results and previous OH RET studies for both the ground and excited electronic states, some significant discrepancies are noted. (C) 1999 American Institute of Physics. [S0021-9606(99)01701-8]. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Kliner, DAV (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. NR 42 TC 48 Z9 48 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 1 PY 1999 VL 110 IS 1 BP 412 EP 422 DI 10.1063/1.478073 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 151AC UT WOS:000077697900052 ER PT J AU Glosli, JN Ree, FH AF Glosli, JN Ree, FH TI The melting line of diamond determined via atomistic computer simulations SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LIQUID CARBON; TEMPERATURE; PRESSURE; GRAPHITE AB The diamond melting line was determined for a model system based on Brenner's bond order potential for hydrocarbon systems. The location of this first-order phase boundary was found by a free energy calculation of the diamond and liquid phases, using atomistic simulation methods. The melting line was found to have a positive slope consistent with the present understanding. The location at lower pressure was also consistent with experiment and a number of other theoretical approaches. The slope is found to increase with pressure. The structure of the liquid is examined as a function of density and is suggestive of a Liquid-liquid phase boundary. (C) 1999 American Institute of Physics. [S0021-9606(99)51201-4]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Glosli, JN (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 19 TC 29 Z9 29 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 1 PY 1999 VL 110 IS 1 BP 441 EP 446 DI 10.1063/1.478103 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 151AC UT WOS:000077697900054 ER PT J AU Runge, K Sumpter, BG Noid, DW Barnes, MD AF Runge, K Sumpter, BG Noid, DW Barnes, MD TI Prediction of quantum dot-like behavior in polymer nanoparticles: Quantum drops SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SEMICLASSICAL CALCULATION; MULTIDIMENSIONAL SYSTEM; BOUND-STATES; EIGENVALUES; ELECTRONS; PARTICLES; SPHERE AB Recent technological advances in the production of polymer particles suggests the feasibility of generating polymer nanoparticles from solution with discrete electronic structure in close analogy with quantum dots. We call these new particles quantum drops, which have controllable physical properties including radius, composition, chemical potential, and magnetic properties. We consider the electronic properties of electrons confined on the surface of these spherical polymer nanoparticles using a new Hamiltonian and semiclassical quantization. (C) 1999 American Institute of Physics. [S0021-9606(99)70701-4]. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Runge, K (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 21 TC 5 Z9 5 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 1 PY 1999 VL 110 IS 1 BP 594 EP 597 DI 10.1063/1.478116 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 151AC UT WOS:000077697900072 ER PT J AU Stamnes, K Ellingson, RG Curry, JA Walsh, JE Zak, BD AF Stamnes, K Ellingson, RG Curry, JA Walsh, JE Zak, BD TI Review of science issues, deployment strategy, and status for the ARM North Slope of Alaska-Adjacent Arctic Ocean climate research site SO JOURNAL OF CLIMATE LA English DT Review ID GROUND-BASED MEASUREMENTS; SURFACE RADIATIVE FLUXES; CLOUD OPTICAL-PROPERTIES; ATMOSPHERIC WATER-VAPOR; SEA-ICE; SNOW-COVER; SOLAR-RADIATION; SPECTRAL ALBEDO; ENERGY BUDGET; AVHRR DATA AB Recent climate modeling results point to the Arctic as a region that is particularly sensitive to global climate change. The Arctic warming predicted by the models to result from the expected doubling of atmospheric carbon dioxide is two to three times the predicted mean global warming, and considerably greater than the warming predicted for the Antarctic. The North Slope of Alaska-Adjacent Arctic Ocean (NSA-AAO) Cloud and Radiation Testbed (CART) site of the Atmospheric Radiation Measurement (ARM) Program is designed to collect data on temperature-ice-albedo and water vapor-cloud-radiation feedbacks, which are believed to be important to the predicted enhanced warming in the Arctic. The most important scientific issues of Arctic, as well as global, significance to be addressed at the NSA-AAO CART site are discussed, and a bl icf overview of the current approach toward, and status of, site development is provided. ARM radiometric and remote sensing instrumentation is already deployed and taking data in the perennial Arctic ice pack as part of the SHEBA (Surface l-leat Budget of the Arctic Ocean) experiment. in parallel with ARM's participation in SHEBA, the NSA-AAO facility near Barrow was formally dedicated on 1 July 1997 and began routine data collection early in 1998. This schedule permits the U.S. Department of Energy's ARM Program, NASA's Arctic Cloud program, and the SHEBA program (funded primarily by the National Science Foundation and the Office of Naval Research) to be mutually supportive. In addition, location of the NSA-AAO Barrow facility on National Oceanic and Atmospheric Administration land immediately adjacent to its Climate Monitoring and Diagnostic Laboratory Barrow Observatory includes NOAA in this major interagency Arctic collaboration. C1 Univ Alaska, Inst Geophys, Fairbanks, AK 99775 USA. Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. Univ Colorado, Dept Aerosp & Engn Sci, Boulder, CO 80309 USA. Univ Illinois, Dept Atmospher Sci, Urbana, IL 61801 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Stamnes, K (reprint author), Univ Alaska, Inst Geophys, 903 Koyukuk Dr,POB 757320, Fairbanks, AK 99775 USA. NR 105 TC 55 Z9 55 U1 0 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD JAN PY 1999 VL 12 IS 1 BP 46 EP 63 DI 10.1175/1520-0442-12.1.46 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 165XZ UT WOS:000078548300005 ER PT J AU Adalsteinsson, D Sethian, JA AF Adalsteinsson, D Sethian, JA TI The fast construction of extension velocities in level set methods SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID UNIFIED MODEL; PROPAGATING INTERFACES; LITHOGRAPHY; SIMULATIONS; DEPOSITION; ALGORITHMS; CURVATURE; FRONTS; FLOW AB Level set techniques are numerical techniques for tracking the evolution of interfaces. They rely on two central embeddings; first, the embedding of the interface as the zero level set of a higher dimensional function, and second, the embedding (or extension) of the interface's velocity to this higher dimensional level set function. This paper applies Sethian's Fast Marching Method, which is a very fast technique for solving the eikonal and related equations, to the problem of building fast and appropriate extension velocities for the neighboring level sets. Our choice and construction of extension velocities serves several purposes. First, it provides a way of building velocities for neighboring level sets in the cases where the velocity is defined only on the front itself. Second, it provides a subgrid resolution not present in the standard level set approach. Third, it provides a way to update an interface according to a given velocity field prescribed on the front in such a way that the signed distance function is maintained, and the front is never re-initialized; this is valuable in many complex simulations. In this paper, we describe the details of such implementations, together with speed and convergence tests and applications to problems in visibility relevant to semi-conductor manufacturing and thin film physics. (C) 1999 Academic Press. C1 Univ Calif Berkeley, Dept Math, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Sethian, JA (reprint author), Univ Calif Berkeley, Dept Math, Berkeley, CA 94720 USA. NR 20 TC 357 Z9 389 U1 2 U2 29 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 JAN 1 PY 1999 VL 148 IS 1 BP 2 EP 22 DI 10.1006/jcph.1998.6090 PG 21 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 152NL UT WOS:000077783600002 ER PT J AU Sussman, M Almgren, AS Bell, JB Colella, P Howell, LH Welcome, ML AF Sussman, M Almgren, AS Bell, JB Colella, P Howell, LH Welcome, ML TI An adaptive level set approach for incompressible two-phase flows SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE incompressible; two-phase flow; level sets; adaptive mesh refinement ID FREE-BOUNDARY PROBLEMS; 2ND-ORDER PROJECTION METHOD; FLUID-FLOWS; MESH REFINEMENT; GRID METHOD; BUBBLES; EQUATIONS; DYNAMICS; COMPLEX; SURFACE AB We present a numerical method using the level set approach for serving incompressible two-phase flow with surface tension. In the level set approach, the free surface is represented as the zero level set of a smooth function; this has the effect of replacing the advection of density, which has steep gradients at the free surface, with the advection of the level set function, which is smooth. In addition, the free surface can merge or break up with no special treatment. We maintain the level set function as the signed distance from the free surface in order to accurately compute flows with high density ratios and stiff surface tension effects. In this work, we couple the level set scheme to an adaptive projection method for the incompressible Navier-Stokes equations, in order to achieve higher resolution of the free surface with a minimum of additional expense. We present two-dimensional axisymmetric and fully three-dimensional results of air bubble and water drop computations. (C) 1999 Academic Press. C1 Univ Calif Davis, Dept Math, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Computat Sci & Engn, Berkeley, CA 94720 USA. RP Sussman, M (reprint author), Univ Calif Davis, Dept Math, Davis, CA 95616 USA. NR 51 TC 324 Z9 337 U1 6 U2 35 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 JAN 1 PY 1999 VL 148 IS 1 BP 81 EP 124 DI 10.1006/jcph.1998.6106 PG 44 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 152NL UT WOS:000077783600005 ER PT J AU Pasik, MF Seidel, DB Lemke, RW AF Pasik, MF Seidel, DB Lemke, RW TI A modified perfectly matched layer implementation for use in electromagnetic PIC codes SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID ABSORBING BOUNDARY-CONDITION; FDTD ANALYSIS; SIMULATIONS; ABSORPTION; WAVES AB A modification to the Berenger perfectly matched layer (PML) absorbing boundary condition that allows it to be used in particle-in-cell applications where the primary power flow through the boundary is due to electromagnetic radiation is presented. Instead of modeling particles within the PML, a term is introduced which diffuses charge conservation errors arising from the removal of particles incident on the PML to the outer boundary. Numerical results are provided to demonstrate the performance of the algorithm. (C) 1999 Academic Press. C1 Sandia Natl Labs, Dept Computat Electromagnet & Plasma Phys, Albuquerque, NM 87185 USA. RP Pasik, MF (reprint author), Sandia Natl Labs, Dept Computat Electromagnet & Plasma Phys, POB 5800, Albuquerque, NM 87185 USA. NR 18 TC 5 Z9 5 U1 0 U2 3 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD JAN 1 PY 1999 VL 148 IS 1 BP 125 EP 132 DI 10.1006/jcph.1998.6107 PG 8 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 152NL UT WOS:000077783600006 ER PT J AU Chang, JP Bulatov, VV Yip, S AF Chang, JP Bulatov, VV Yip, S TI Molecular dynamics study of edge dislocation motion in a bcc metal SO JOURNAL OF COMPUTER-AIDED MATERIALS DESIGN LA English DT Article; Proceedings Paper CT 5th International Conference on Advanced Materials (IUMRS) CY JUN 13-18, 1999 CL BEIJING, PEOPLES R CHINA SP Union Mat Res Soc DE atamistic simulation; dislocation mobility; dislocation velocity; hyperdynamics; molecular dynamics simulations; molybdenum ID TRANSITION-METALS; INFREQUENT EVENTS AB The motion of an edge dislocation gliding in a bcc lattice under shear loading is simulated by molecular dynamics. The time evolution of the dislocation profile, derived by analyzing the spatial disregistry between two adjacent atomic rows, reveals frequent nucleation of double kinks and little activity in kink migration in association with the dislocation motion. An essentially linear stress variation is obtained, while the temperature dependence suggests the mechanism of phonon drag. C1 MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Chang, JP (reprint author), MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. NR 18 TC 23 Z9 26 U1 0 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0928-1045 J9 J COMPUT-AIDED MATER JI J. Comput-Aided Mater. Des. PY 1999 VL 6 IS 2-3 BP 165 EP 173 DI 10.1023/A:1008716911551 PG 9 WC Computer Science, Interdisciplinary Applications; Materials Science, Multidisciplinary SC Computer Science; Materials Science GA 336DV UT WOS:000088287400010 ER PT J AU Cai, W Bulatov, VV Yip, S AF Cai, W Bulatov, VV Yip, S TI Kinetic Monte Carlo method for dislocation glide in silicon SO JOURNAL OF COMPUTER-AIDED MATERIALS DESIGN LA English DT Article; Proceedings Paper CT 5th International Conference on Advanced Materials (IUMRS) CY JUN 13-18, 1999 CL BEIJING, PEOPLES R CHINA SP Union Mat Res Soc DE double-kink; kinetic Monte Carlo; partial dislocation; Si ID DISSOCIATED DISLOCATIONS; SIMULATION; MOBILITY; DYNAMICS AB A kinetic Monte Carlo (KMC) approach to the mesoscale simulation of dislocation glide via the kink mechanism is developed. In this paper we present the details of the KMC methodology, highlighting three features: (1) inclusion of dislocation dissociation; (2) efficient method of sampling the double-kink nucleation process; and (3) exact calculation of dislocation segment interactions. C1 MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. EM caiwei@mit.edu OI Cai, Wei/0000-0001-5919-8734 NR 18 TC 13 Z9 13 U1 0 U2 2 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0928-1045 J9 J COMPUT-AIDED MATER JI J. Comput-Aided Mater. Des. PY 1999 VL 6 IS 2-3 BP 175 EP 183 DI 10.1023/A:1008730124719 PG 9 WC Computer Science, Interdisciplinary Applications; Materials Science, Multidisciplinary SC Computer Science; Materials Science GA 336DV UT WOS:000088287400011 ER PT J AU Xu, Q Heinisch, HL Yoshiie, T AF Xu, Q Heinisch, HL Yoshiie, T TI Effects of damage rate on defect cluster formation in copper under low dose irradiation SO JOURNAL OF COMPUTER-AIDED MATERIALS DESIGN LA English DT Article; Proceedings Paper CT 5th International Conference on Advanced Materials (IUMRS) CY JUN 13-18, 1999 CL BEIJING, PEOPLES R CHINA SP Union Mat Res Soc DE cascade effects; copper; defect cluster; dose rate; MC simulation ID TRANSIENT; CASCADES; NEUTRON; NICKEL AB The dependence of defect cluster formation on dose rate is an important factor in understanding the mechanisms of microstructure evolution under irradiation. In the present study, the effects of dose rate on the formation of vacancy clusters and self-interstitial atom (SIA) clusters during low dose irradiation up to 0.01 dpa were investigated. The densities of SIA clusters formed at 200 K and 458 K and Vacancy clusters formed at 200 K were found to be independent of the dose rate. Vacancy cluster densities were found to be dependent on the dose rate at temperatures between 200 K and 458 K. The results can be explained by the migration and thermal stability of defects, which are determined by irradiation temperature. C1 Kyoto Univ, Inst Res Reactor, Osaka 5900494, Japan. Pacific NW Lab, Richland, WA 99352 USA. RP Xu, Q (reprint author), Kyoto Univ, Inst Res Reactor, Osaka 5900494, Japan. NR 15 TC 3 Z9 3 U1 1 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0928-1045 J9 J COMPUT-AIDED MATER JI J. Comput-Aided Mater. Des. PY 1999 VL 6 IS 2-3 BP 215 EP 223 DI 10.1023/A:1008730318477 PG 9 WC Computer Science, Interdisciplinary Applications; Materials Science, Multidisciplinary SC Computer Science; Materials Science GA 336DV UT WOS:000088287400014 ER PT J AU Heinisch, HL Singh, BN Golubov, SI AF Heinisch, HL Singh, BN Golubov, SI TI A kinetic Monte Carlo study of mixed 1D/3D defect migration SO JOURNAL OF COMPUTER-AIDED MATERIALS DESIGN LA English DT Article; Proceedings Paper CT 5th International Conference on Advanced Materials (IUMRS) CY JUN 13-18, 1999 CL BEIJING, PEOPLES R CHINA SP Union Mat Res Soc DE computer simulation; defect migration; diffusion; irradiation effects; kinetic Monte Carlo ID SIMULATION; EVOLUTION; CASCADES; COMPUTER; METALS AB Defect clusters form readily in collision cascades in metals, and some of the self-interstitial atom clusters form as crowdion clusters that diffuse by one-dimensional migration along a close-packed direction. Defect interactions and thermal fluctuations can cause the direction of one-dimensional migration to change, resulting in a mixed one-dimensional/ three-dimensional migration. Kinetic Monte Carlo computer simulations applied to model systems are used to investigate the effects of one-dimensional, three-dimensional and mixed one-dimensional/ three-dimensional migration on defect reaction kinetics. The functional relationships between the sink strength, the size of sinks and the average distance between direction changes during mixed one- dimensional/three-dimensional migration are explored. C1 Pacific NW Lab, Richland, WA 99352 USA. Riso Natl Lab, DK-4000 Roskilde, Denmark. Inst Phys & Power Engn, Obninsk, Russia. RP Heinisch, HL (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 14 TC 2 Z9 2 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0928-1045 J9 J COMPUT-AIDED MATER JI J. Comput-Aided Mater. Des. PY 1999 VL 6 IS 2-3 BP 277 EP 282 DI 10.1023/A:1008777901639 PG 6 WC Computer Science, Interdisciplinary Applications; Materials Science, Multidisciplinary SC Computer Science; Materials Science GA 336DV UT WOS:000088287400018 ER PT J AU Kletskova, T Czerwinski, K Gelbard, E Yip, S AF Kletskova, T Czerwinski, K Gelbard, E Yip, S TI Modeling cation exchange in zeolitic nuclear waste form SO JOURNAL OF COMPUTER-AIDED MATERIALS DESIGN LA English DT Article; Proceedings Paper CT 5th International Conference on Advanced Materials (IUMRS) CY JUN 13-18, 1999 CL BEIJING, PEOPLES R CHINA SP Union Mat Res Soc DE atomistic simulation; ion exchange; isotherm; radionuclide; waste form ID SIMULATION AB Zeolites are currently being considered as an encapsulation material for high-level nuclear wastes. As a first step toward understanding the mechanisms of radionuclide migration in such molecular crystals, we apply an atomistic simulation approach to the study of ion exchange, which is assumed to be the underlying chemical process for the release of radioactive cations. Specifically, we investigate the Cs-Na cation exchange isotherm for dehydrated sodalite waste form. Our calculations indicate significant relaxation effects of the sodalite cage, in the form of displacement of cation adsorption sites and cage distortion. C1 MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Argonne Natl Lab, Reactor Anal Div, Argonne, IL 60439 USA. RP Kletskova, T (reprint author), MIT, Dept Nucl Engn, 77 Massachusetts Ave,Room 24-302, Cambridge, MA 02139 USA. NR 20 TC 2 Z9 2 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0928-1045 J9 J COMPUT-AIDED MATER JI J. Comput-Aided Mater. Des. PY 1999 VL 6 IS 2-3 BP 363 EP 368 DI 10.1023/A:1008780522789 PG 6 WC Computer Science, Interdisciplinary Applications; Materials Science, Multidisciplinary SC Computer Science; Materials Science GA 336DV UT WOS:000088287400025 ER PT J AU Boyle, TJ Gallegos, JJ Pedrotty, DM Mechenbier, ER Scott, BL AF Boyle, TJ Gallegos, JJ Pedrotty, DM Mechenbier, ER Scott, BL TI Hetero-alkoxide group (IV) and (V) neo-pentoxide compounds. Syntheses, characterizations, and X-ray structures of [Zr(mu-OCHMe2)(OCH2CMe3)(3)(HOCH2CMe3)](2) and [Ta(mu-OCH2Me)(OCH2CMe3)(4)](2) SO JOURNAL OF COORDINATION CHEMISTRY LA English DT Article DE metal alkoxides; metal-alkoxide ceramics; zirconium; tantulam; X-ray structures ID THIN-FILMS; SOLUTION ROUTES; PRECURSORS AB The alcoholysis exchange between excess HONp and [Zr(OPri)(4)(HOPri)](2) or "Ta(OEt)(5)" led to isolation of the mixed-alkoxide compounds [Zr(mu-OPri)(ONp)(3)(HONp)](2) (1) and [Ta(mu-OEt)(ONp)(4)](2) (2), respectively. Compounds 1 and 2 were found to adopt an edge-shared bioctahedral geometry, [M(mu-OR')(OR)(5)](2), with the smaller ligands acting as the bridge between the two metal centers. For 1, the octahedral geometry around the metal center is completed by the coordination of a HONp solvent molecule. The solid state structure of 1 was retained in saturated solutions but at lower concentrations, dynamic behavior associated with a mononuclear-dinuclear equilibrium was observed. For 2, at low concentrations an equilibrium between mononuclear and dinuclear complexes was noted; however, at higher concentrations a dinuclear-higher-nuclearity equilibrium was noted. C1 Sandia Natl Labs, Adv Mat Lab, Albuquerque, NM 87106 USA. Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Xray Diffract Lab, Los Alamos, NM 87545 USA. RP Boyle, TJ (reprint author), Sandia Natl Labs, Adv Mat Lab, 1001 Univ Blvd SE, Albuquerque, NM 87106 USA. RI Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 28 TC 27 Z9 27 U1 0 U2 3 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0095-8972 J9 J COORD CHEM JI J. Coord. Chem. PY 1999 VL 47 IS 1 BP 155 EP 171 DI 10.1080/00958979908024550 PG 17 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 193ZH UT WOS:000080167300013 ER PT J AU Hoffman, DC AF Hoffman, DC TI One atom-at-a-time chemistry of the heaviest elements SO JOURNAL OF COSMETIC SCIENCE LA English DT Article C1 Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Hoffman, DC (reprint author), Lawrence Berkeley Lab, Div Nucl Sci, MS-70A-3307, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 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 JAN-FEB PY 1999 VL 50 IS 1 BP 96 EP 97 PG 2 WC Chemistry, Applied; Dermatology SC Chemistry; Dermatology GA 175RP UT WOS:000079109000023 ER PT J AU Bertness, KA Kurtz, SR Asher, SE Reedy, RC AF Bertness, KA Kurtz, SR Asher, SE Reedy, RC TI AlInP benchmarks for growth of AlGaInP compounds by organometallic vapor-phase epitaxy SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE oxygen impurity; indium compounds; AlGaInP; organometallic vapor-phase epitaxy (OMVPE); photocurrent; secondary ion mass spectrometry (SIMS) ID MOLECULAR-BEAM EPITAXY; TANDEM SOLAR-CELLS; OXYGEN INCORPORATION; SUBSTRATE MISORIENTATION; DOPING CHARACTERISTICS; DOPED INGAAIP; DEPOSITION; RECOMBINATION; TRIMETHYLINDIUM; ALGAAS AB We have demonstrated that source material and growth system purity can be successfully evaluated by characterizing AlInP samples grown by organometallic vapor-phase epitaxy with photocurrent versus voltage measurements in an electrochemical cell. The samples can be grown and characterized in about 1 h, making them well-suited for system benchmarks. Zn-doped AlInP has the greatest sensitivity for O contamination, a recurring problem in the growth of AlGaInP alloys. High O concentrations in the Zn-doped benchmarks cause the photoresponse to fall dramatically. Secondary ion mass spectrometry data are consistent with compensation of Zn acceptor states by O donor-like trap states. Photocurrents of Si-doped and Se-doped AlInP are less sensitive to the O contamination, and the behavior of these n-type samples suggests that multiple energy states can be associated with the O impurities and dopant atoms. The benchmarks have been used to identify O contamination in trimethyl indium and phosphine and to evaluate new growth systems. Application of the benchmark to growth of GaInP solar cells with AlInP window layers is also discussed. Published by Elsevier Science B.V. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Bertness, KA (reprint author), Natl Inst Stand & Technol, Mailstop 815-04,325 Broadway, Boulder, CO 80303 USA. EM bertness@boulder.nist.gov NR 34 TC 16 Z9 16 U1 1 U2 11 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 JAN PY 1999 VL 196 IS 1 BP 13 EP 22 DI 10.1016/S0022-0248(98)00751-9 PG 10 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 154GH UT WOS:000077880300002 ER PT J AU Carter, DC Wright, B Miller, T Chapman, J Twigg, P Keeling, K Moody, K White, M Click, J Ruble, JR Ho, JX Adcock-Downey, L Bunick, G Harp, J AF Carter, DC Wright, B Miller, T Chapman, J Twigg, P Keeling, K Moody, K White, M Click, J Ruble, JR Ho, JX Adcock-Downey, L Bunick, G Harp, J TI Diffusion-controlled crystallization apparatus for microgravity (DCAM): flight and ground-based applications SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 7th International Conference on Crystallization of Biological Macromolecules CY MAY 03-08, 1998 CL GRANADA, SPAIN DE DCAM; protein; crystal; microgravity; Mir; diffusion AB A versatile microdialysis counterdiffusion apparatus was developed in response to special exploratory opportunities for long-duration protein crystal growth experiments presented by the US and Russian Space Program. Challenged to reduce man-tended dependence during this phase, the hardware was designed to eliminate in-flight activation or deactivation. In addition, a disposable interface was incorporated in the design to allow for improved logistics and handling during the pre-flight loading and post-flight distribution of the flight samples for each experiment. The hardware is referred to as the diffusion-controlled crystallization apparatus for microgravity or DCAM (pronounced "dee-cam") which utilizes the dialysis method and allows the equilibration rate of each individual experiment to be passively controlled from several days to several months. Precision control of the rate of approach to supersaturation has routinely produced macro (5 mm to 1.25 cm) crystals for a variety of proteins in this hardware. A description of the hardware and preliminary results from a series of US Shuttle/Mir flight experiments are presented. (C) 1999 Elsevier Science B.V. All rights reserved. C1 New Century Pharmaceut Inc, Huntsville, AL 35824 USA. Code ES76 Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Univ Space Res Assoc, Huntsville, AL 35805 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Carter, DC (reprint author), New Century Pharmaceut Inc, 895 Martin Rd, Huntsville, AL 35824 USA. NR 6 TC 27 Z9 30 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 JAN PY 1999 VL 196 IS 2-4 BP 602 EP 609 DI 10.1016/S0022-0248(98)00857-4 PG 8 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 161YY UT WOS:000078319200047 ER PT J AU Jenkins, ML Kirk, MA Fukushima, H AF Jenkins, ML Kirk, MA Fukushima, H TI On the application of the weak-beam technique to the determination of the sizes of small point-defect clusters in ion-irradiated copper SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Article DE weak-beam microscopy; defects; clusters; irradiation damage ID DAMAGE AB We have made an analysis of the conditions necessary for the successful use of the weak-beam technique for identifying and characterizing small point defect clusters in ion-irradiated copper. The visibility of small defects was found to depend only weakly on the beam convergence. In general, the image sizes of small clusters were found to be most sensitive to the magnitude of s(g), with the image sizes of some individual defects changing by large amounts with changes in s(g) as small as 0.025 nm(-1). The most reliable information on the true defect size is likely to be obtained by taking a series of 5-9 micrographs with a systematic variation of deviation parameter from 0.2-0.3 nm(-1). This procedure allows size information to be obtained down to a resolution limit of about 0.5 nm for defects situated throughout a foil thickness of 60 nm. The technique has been applied to the determination of changes in the sizes of small defects produced by a low-temperature in-situ irradiation and annealing experiment. C1 Univ Oxford, Dept Mat, Oxford OX1 3PH, England. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Hiroshima Univ, Fac Engn, Higashihiroshima 7398527, Japan. RP Jenkins, ML (reprint author), Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England. NR 8 TC 12 Z9 12 U1 0 U2 5 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 1999 VL 48 IS 4 BP 323 EP 332 PG 10 WC Microscopy SC Microscopy GA 230FC UT WOS:000082240300003 ER PT J AU Okamoto, PR Lam, NQ Ohnuki, S AF Okamoto, PR Lam, NQ Ohnuki, S TI Do cracks melt their way through solids? SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Article DE glass transition; amorphization; fracture; irradiation ID INTERMETALLIC COMPOUNDS; AMORPHIZATION AB Real-time, in-situ fracture studies in the high-voltage electron microscope (HVEM) show that microscopically thin regions of amorphous NiTi form ahead of moving crack tips in the B2-NiTi intermetallic compound. This occurs during tensile straining at temperatures equal to or below 600 K. The cut-off temperature of 600 It for this stress-induced melting (or amorphization) is identical to that reported in the literature for heavy-ion-induced amorphization of the intermetallic NiTi and for ion-beam-mixing-induced amorphization of Ni and a multilayers. The higher crystallization temperatures (similar to 800 K) of NiTi glasses produced by rapid quenching can also be reduced by heavy-ion irradiation to 600 It (but not lower than). This strongly suggests that ion-beam-induced relaxation processes allow the formation of a unique, fully relaxed glassy state characterized by a unique isothermal crystallization temperature. We believe this unique temperature is the Kauzmann isentropic glass-transition temperature of an ideal glassy state having the same entropy as the crystalline state. The formation of this ideal glassy state via solid-state disordering processes can be understood as the most energetically-favoured, kinetically-constrained melting response of crystalline materials driven far from equilibrium at very low temperatures. C1 Hokkaido Univ, Dept Mat & Engn, Sapporo, Hokkaido, Japan. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Ohnuki, S (reprint author), Hokkaido Univ, Dept Mat & Engn, Sapporo, Hokkaido, Japan. NR 18 TC 4 Z9 4 U1 0 U2 4 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 1999 VL 48 IS 5 BP 481 EP 487 PG 7 WC Microscopy SC Microscopy GA 250ZT UT WOS:000083420700002 ER PT J AU Allen, CW Song, MH Furuya, K Birtcher, RC Mitsuishi, K Dahmen, U AF Allen, CW Song, MH Furuya, K Birtcher, RC Mitsuishi, K Dahmen, U TI Xe precipitates at grain boundaries in Al under 1 MeV electron irradiation SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Article DE high-resolution electron microscopy; Al mazed bicrystal; Xe precipitate; grain boundary; irradiation ID ALUMINUM AB Crystalline nanoprecipitates of Xe have been produced by ion implantation into mazed bicrystalline Al at 300 K, in which the matrix grain boundaries are mainly 90 degrees lilt boundaries. Within Al grains, Xe nanocrystals are fee, isotactic with the Al and cuboctohedral in shape with {111} and {100} facets. With an off-axial imaging technique, the nanocrystals were structure imaged against a relatively featureless matrix background. In contrast to metal precipitates in Al, such as Pb, Xe precipitates straddling a matrix grain boundary are bicrystals as small as approximately 2 nm in diameter. Larger Xe precipitates tend to avoid boundaries that are inclined away from asymmetrical orientation and which have a significant twist component. Under the 1 MeV electron irradiation employed for HREM observation, small Xe nanocrystals near a grain boundary may migrate to the boundary and coalesce with other Xe precipitates. The structural observations are rationalized on a simple geometrical interpretation. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Natl Res Inst Met, Tsukuba, Ibaraki 3050003, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Allen, CW (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM allen@aaem.amc.anl.gov NR 10 TC 10 Z9 10 U1 1 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 1999 VL 48 IS 5 BP 503 EP 509 PG 7 WC Microscopy SC Microscopy GA 250ZT UT WOS:000083420700005 ER PT J AU Kobayashi, Y Muto, S Echer, CJ Tanabe, T AF Kobayashi, Y Muto, S Echer, CJ Tanabe, T TI On extended energy-loss fine structure data analysis for obtaining reliable structural parameters SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Article DE Debye-Waller factor; EXELFS; inter-atomic distance; radial distribution function ID EXELFS AB We examined extended energy-loss fine structure (EXELFS) data analysis for obtaining reliable values of structural parameters, and its practical guidelines are presented. We found that the ratio method is unstable and gives reliable results only when the calculated radial distribution function shows good peak separation, whereas the curve-fitting is rather robust for the quantitative analysis. We introduced a simple optimization method to avoid the instability associated with the ratio method so that two experiments on the same area at different temperatures should give time same coordination number. The coordination number and Debye-Waller factor derived from the area having different thickness resulted in the same values within the experimental accuracy up to the thickness of 0.4 lambda (lambda: plasmon mean free path), while the inter-atomic distance was linearly decreased with sample thickness also up to that thickness. This suggests that EXELFS experiments must be conducted for sample thickness <0.4 lambda. C1 Nagoya Univ, Dept Nucl Engn, Grad Sch Engn, Ctr Integrated Res Sci & Engn,Chikusa Ku, Nagoya, Aichi 4648603, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Muto, S (reprint author), Nagoya Univ, Dept Nucl Engn, Grad Sch Engn, Ctr Integrated Res Sci & Engn,Chikusa Ku, Nagoya, Aichi 4648603, Japan. EM muto@cirse.nagoya-u.ac.jp RI Muto, Shunsuke/G-5741-2012 OI Muto, Shunsuke/0000-0001-6275-0649 NR 9 TC 6 Z9 6 U1 0 U2 4 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 EI 1477-9986 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 1999 VL 48 IS 5 BP 525 EP 529 PG 5 WC Microscopy SC Microscopy GA 250ZT UT WOS:000083420700008 ER PT J AU Hashimoto, N Wakai, E Robertson, JP AF Hashimoto, N Wakai, E Robertson, JP TI Damage structure in austenitic stainless steel 316LN irradiated at low temperature in the HFIR SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Letter DE neutron irradiation; austenitic stainless steel; Frank loop; irradiation hardening ID EVOLUTION AB An austenitic stainless steel 316LN irradiated to damage levels of about 3 dpa at irradiation temperatures of about 90 degrees C and 250 degrees C has been examined by transmission electron microscopy. The irradiation at 90 degrees C and 250 degrees C induced a dislocation loop density of 3.5 x 10(22) m(-3) and 5.2 x 10(22) m(-3), and a black dot density of 2.2 x 10(23) m(-3) and 1.1 x 10(23) m(-3), respectively, in the steel. A low density (<1 x 10(19) m(-3)) of radiation-enhanced precipitates was observed in the matrix at both irradiation temperatures. No cavities were observed at both irradiation temperatures. These features are correlated with the changes in tensile properties. It is concluded that the dislocation loops and the black dots cause irradiation hardening and a decrease in the uniform elongation in the 316LN steel irradiated at low temperatures. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Japan Atom Energy Res Inst, Tokai, Ibaraki 3191195, Japan. RP Hashimoto, N (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI HASHIMOTO, Naoyuki/D-6366-2012; Wakai, Eiichi/L-1099-2016 NR 20 TC 1 Z9 1 U1 0 U2 5 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 1999 VL 48 IS 5 BP 575 EP 580 PG 6 WC Microscopy SC Microscopy GA 250ZT UT WOS:000083420700015 ER PT J AU Takeda, M Ohnuki, S Okamoto, PR Lam, NQ AF Takeda, M Ohnuki, S Okamoto, PR Lam, NQ TI Formation of amorphous zones along the crack of poly-silicon film during straining experiment in transmission microscope SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Article DE poly-Si; crack tip; stress-induced amorphization AB An 'in-situ' straining experiment has been carried out to clarify the propagation process of a crack tip in poly-crystalline film of silicon. After rapid propagation of cracks, the band structure with half-toned contrast is observed on the edge of the crack, which is a deformation-induced amorphous zone. The amorphous zone is 40-90 nm in width and includes fine crystalline particles of 0.8 nm in size. From those results, the local amorphization process and the possible fracture mechanism are discussed. C1 Hokkaido Univ, Dept Mat Engn, Kita Ku, Sapporo, Hokkaido 0608628, Japan. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Ohnuki, S (reprint author), Hokkaido Univ, Dept Mat Engn, Kita Ku, Kita 13,Nishi 8, Sapporo, Hokkaido 0608628, Japan. NR 6 TC 5 Z9 5 U1 0 U2 3 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 1999 VL 48 IS 5 BP 609 EP 611 PG 3 WC Microscopy SC Microscopy GA 250ZT UT WOS:000083420700022 ER PT J AU Allen, CW Song, M Furuya, K Birtcher, RC Donnelly, SE Mitsuishi, K AF Allen, CW Song, M Furuya, K Birtcher, RC Donnelly, SE Mitsuishi, K TI Behaviour of nanocrystalline Xe precipitates in Al under 1 MeV electron irradiation SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Article; Proceedings Paper CT International Workshop on Stuctures and Properties of Multi-lattice Materials - Toward Characterization and Control Nanocrystals CY FEB 03-05, 1999 CL TSUKUBA, JAPAN SP Natl Res Inst Met, Sci & Technol Agcy, Japan Int X, Japan Int Sci & Technol Exchange Ctr DE high-resolution electron microscopy; Xe precipitate; irradiation; nanocrystal ID ALUMINUM AB Crystalline nanoprecipitates of Xe have been produced by ion implantation into high purity Al at 300 K. With an off-zone axis transmission electron microscopy (TEM) imaging technique, the nanocrystals may be clearly structure imaged against a nearly featureless background. Under the 1 MeV electron irradiation employed for the HREM observation, Xe nanocrystals exhibit a number of readily observed physical phenomena including migration within the matrix, changes in shape, faulting, melting, crystallization and coalescence. The various phenomena observed as changes in the Xe nanocrystals reflect changes of matrix cavity-surface structure. The Xe nanocrystal thus allows investigation indirectly into changes in interface morphology at the atomic level, resulting in this instance from electron irradiation damage. Such changes have previously been inaccessible to observation. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Natl Res Inst Met, Tsukuba, Ibaraki 3050003, Japan. Univ Salford, Manchester M5 4WT, Lancs, England. RP Allen, CW (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM allen@aaem.amc.anl.gov OI Donnelly, Stephen/0000-0002-9749-5550 NR 16 TC 5 Z9 5 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 1999 VL 48 SU S BP 1025 EP 1030 PG 6 WC Microscopy SC Microscopy GA 306CW UT WOS:000086579800006 ER PT J AU Johnson, E Johansen, A Dahmen, U Gabrisch, H Hagege, S AF Johnson, E Johansen, A Dahmen, U Gabrisch, H Hagege, S TI Multiphase and multicomponent nanoscale inclusions in aluminium SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Article; Proceedings Paper CT International Workshop on Stuctures and Properties of Multi-lattice Materials - Toward Characterization and Control Nanocrystals CY FEB 03-05, 1999 CL TSUKUBA, JAPAN SP Natl Res Inst Met, Sci & Technol Agcy, Japan Int X, Japan Int Sci & Technol Exchange Ctr DE nanoscale inclusions; aluminium; transmission electron microscopy; alloy precipitates; melting and solidification ID ELECTRON-MICROSCOPY OBSERVATIONS; MELTING TEMPERATURE; THALLIUM INCLUSIONS; PB INCLUSIONS; AL; SOLIDIFICATION; IMPLANTATION; MORPHOLOGY; SYSTEMS; GROWTH AB Ion implantation or rapid solidification can be used to process smaller amounts of alloys containing nanosized inclusions of elements that are insoluble in the matrix. The structure, morphology and properties of such inclusions have been investigated using transmission electron microscopy (TEM). Earlier, most of this research has been devoted to the study of elemental single-phase inclusions, while less effort has been given to multiphase and multicomponent inclusions. Multiphase elemental inclusions can be made from allotropic inclusion elements which have two or more different crystal structures, while multicomponent inclusions consist of two or more elements that are immiscible with the matrix. It is the aim of the present paper to describe the structure and properties of both types of inclusions in aluminium represented by Tl inclusions and alloy inclusions of Pb with Bi and Cd, respectively. C1 Orsted Lab, DK-2100 Copenhagen O, Denmark. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. CNRS, CECM, F-94407 Vitry Sur Seine, France. RP Johnson, E (reprint author), Orsted Lab, Univ Parken 5, DK-2100 Copenhagen O, Denmark. RI Gabrisch, Heike/I-5021-2013 NR 23 TC 7 Z9 7 U1 1 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 1999 VL 48 SU S BP 1031 EP 1036 PG 6 WC Microscopy SC Microscopy GA 306CW UT WOS:000086579800007 ER PT J AU Powell, CJ Jablonski, A Tilinin, IS Tanuma, S Penn, DR AF Powell, CJ Jablonski, A Tilinin, IS Tanuma, S Penn, DR TI Surface sensitivity of Auger-electron spectroscopy and X-ray photoelectron spectroscopy SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article DE Auger-electron spectroscopy; X-ray photoelectron spectroscopy; surface sensitivity; elastic-electron scattering; inelastic-electron scattering ID MEAN FREE PATHS; ANGLE-RESOLVED XPS; ELASTIC-SCATTERING; ESCAPE DEPTH; POLYCRYSTALLINE SOLIDS; SIGNAL PHOTOELECTRONS; ANGULAR-DISTRIBUTION; ATTENUATION LENGTHS; QUANTITATIVE AES; OPTICAL-DATA AB A convenient measure of surface sensitivity in Auger-electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) is the mean escape depth (MED). If the effects of elastic-electron scattering are neglected, the MED is equal to the electron inelastic mean foe path (IMFP) multiplied by the cosine of the emission angle with respect to the surface normal, and depends on the material and electron energy of interest. An overview is given hen of recent calculations of IMFPs for 50-2000 eV electrons in a range of materials. This work has led to the development of a predictive formula based on the Bethe equation for inelastic electron scattering in matter from which IMFPs can be determined. Estimates show, however, that elastic-electron scattering can significantly modify the: MED. Thus, for AES, the MED will be reduced by up to about 35%. For XPS, however, the MED can be changed by up to +/- 30% for common measurement conditions although it can be much larger (by up to a factor of 2) for near-grazing emission angles. Ratios of MED values, calculated with elastic scattering considered and neglected for XPS from the 3s, 3p, and 3d subshells of silver with Mg K alpha X-rays are approximately constant (to about 10%) over a range of emission angles that varies from 40 degrees to 60 degrees depending on the subshell and the angle of X-ray incidence. Recommendations are given on how to determine the optimum range of emission angles for satisfactory analysis of angle-resolved XPS (ARXPS) data. Definitions are included of three terms often used for describing surface sensitivity (IMFP, MED, and effective attenuation length (EAL)), and examples are given of the varying magnitudes of these quantities for different analytical conditions. (C) 1999 Elsevier Science B.V. All rights reserved. C1 NIST, Div Surface & Microanal Sci, Gaithersburg, MD 20899 USA. Polish Acad Sci, Inst Phys Chem, PL-01224 Warsaw, Poland. Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Japan Energy ARC Co Ltd, Toda, Saitama 335, Japan. NIST, Div Electron & Opt Phys, Gaithersburg, MD 20899 USA. RP Powell, CJ (reprint author), NIST, Div Surface & Microanal Sci, Gaithersburg, MD 20899 USA. RI Tanuma, Shigeo/H-2681-2011 NR 48 TC 122 Z9 122 U1 5 U2 39 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD JAN PY 1999 VL 98 BP 1 EP 15 DI 10.1016/S0368-2048(98)00271-0 PG 15 WC Spectroscopy SC Spectroscopy GA 168FW UT WOS:000078681900003 ER PT J AU Fisher, GL Hooper, A Opila, RL Jung, DR Allara, DL Winograd, N AF Fisher, GL Hooper, A Opila, RL Jung, DR Allara, DL Winograd, N TI The interaction between vapor-deposited Al atoms and methylester-terminated self-assembled monolayers studied by time-of-flight secondary ion mass spectrometry, X-ray photoelectron spectroscopy and infrared reflectance spectroscopy SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article DE monolayer; metal deposition; time-of-flight; overlayer; infrared ID ORGANIZED MOLECULAR ASSEMBLIES; TOF-SIMS; FUNCTIONAL-GROUPS; CONDUCTING POLYMER; METAL OVERLAYERS; SURFACE-ANALYSIS; GOLD; FILMS; XPS; PENETRATION AB The deposition of 2 Angstrom of Al metal onto a monolayer of methylester-terminated alkanethiolate(HS(CH2)(15)CO2CH3) self-assembled on polycrystalline Au(lll) was studied using time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS) and infrared reflectance spectroscopy (IRS), The deposited Al was found to be highly reactive with the oxygen atoms in the self-assembled monolayer terminal functional group. No reactivity between Al and the methylene backbone of the monolayer was observed, nor was any Al observed at the monolayer/Au interface. However, the deposition of Al does induce some chain disordering. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Penn State Univ, Dept Chem, Davey Lab 152, University Pk, PA 16802 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Fisher, GL (reprint author), Penn State Univ, Dept Chem, Davey Lab 152, University Pk, PA 16802 USA. OI Winograd, Nicholas/0000-0002-2690-7714 NR 45 TC 22 Z9 22 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD JAN PY 1999 VL 98 BP 139 EP 148 DI 10.1016/S0368-2048(98)00283-7 PG 10 WC Spectroscopy SC Spectroscopy GA 168FW UT WOS:000078681900015 ER PT J AU Reynolds, HL Kang, SH Morris, JW AF Reynolds, HL Kang, SH Morris, JW TI The creep behavior of In-Ag eutectic solder joints SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE creep; indium-silver solder; low temperature solder ID SN; DEFORMATION AB The addition of 3 wt.% Ag to In results in a eutectic composition with improved mechanical properties while only slightly lowering the melting temperature. Steady-state creep properties of In-Ag eutectic solder joints have been measured using constant load tests at 0, 30, 60, and 90 degrees C. Constitutive equations are derived to describe the creep behavior. The data are well represented by an equation of the form proposed by Dorn: a power-law equation applies to each independent creep mechanism. Two parallel mechanisms were observed for the In-Ag eutectic joints. The high-stress mechanism is a bulk mechanism with a thermal dependence dominated by the thermal dependence of creep in the In-rich matrix. The low-stress mechanism is a grain boundary mechanism. Results of this work are discussed with regard to creep behavior of typical eutectic systems. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RP Reynolds, HL (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. NR 22 TC 16 Z9 24 U1 1 U2 3 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 JAN PY 1999 VL 28 IS 1 BP 69 EP 75 DI 10.1007/s11664-999-0197-5 PG 7 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 157JL UT WOS:000078057700012 ER PT J AU Salim, MM France, DM Panchal, CB AF Salim, MM France, DM Panchal, CB TI Heat transfer enhancement on the outer surface of spirally indented tubes SO JOURNAL OF ENHANCED HEAT TRANSFER LA English DT Article DE enhanced heat transfer; spirally indented tubes; annulus flows ID PRESSURE-DROP CHARACTERISTICS; FLUTED ANNULI AB Heat transfer enhancement on the outer surface of spirally indented tubes was investigated experimentally, The spirally indented tubes studied were characterized by thin walls with a spiral groove on the outer surface which produced a spiral protrusion of the material on the inner surface. Heat transfer data were obtained from experiments in horizontal spirally, indented tubes (inside diameter = 23.8 mm) placed inside of a smooth outer tube forming an annulus. Heated water flowed inside the tubes, and chilled water in the surrounding annulus. A smooth tube and three spirally indented tubes were tested with indentation depth to tube inside diameter ratios of 0.0075, 0.021 and 0.038. The ratio of indentation pitch to inside tube diameter was fixed at 0.9 in all tests producing a ratio of pitch to indentation depth of 23.7 to 120. The annulus flow was turbulent in all tests with the Reynolds number in the range of 7,000 to 115, 300, Heat transfer results for the outside surface of the spirally indented tubes were compared to that of smooth tubes and to that of spirally indented tube inside surfaces, A correlation equation was developed to predict the outer surface heat transfer coefficient of spirally indented tubes over the parameter range of the data. C1 Univ Illinois, Dept Mech Engn MC 251, Chicago, IL 60607 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP France, DM (reprint author), Univ Illinois, Dept Mech Engn MC 251, 842 W Taylor St, Chicago, IL 60607 USA. NR 14 TC 3 Z9 3 U1 3 U2 4 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1065-5131 J9 J ENHANC HEAT TRANSF JI J. Enhanc. Heat Transf. PY 1999 VL 6 IS 5 BP 327 EP 341 PG 15 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 225MR UT WOS:000081965800001 ER PT J AU Ravigururajan, TS Drost, MK AF Ravigururajan, TS Drost, MK TI Single-phase flow thermal performance characteristics of a parallel microchannel heat exchanger SO JOURNAL OF ENHANCED HEAT TRANSFER LA English DT Article DE microchannel heat exchangers; high flux heat transfer; heat transfer enhancement ID CHANNEL; MODULE AB The paper outlines the results from a recent experimental study conducted on the single-phase flow characteristics of Refrigerant 124 in a parallel microchannel heat exchanger (MCHX), Single-phase tests were conducted on a parallel microchannel heat exchanger. The experimental study was conducted for a Reynolds number range of 220 to 1250 and a heat flux range of 30 to 90 kW/m(2). The data were compared with the predictions based on established developing, laminar flow concepts. The results showed that the increase in heat transfer coefficient was nearly 2 to 8 times the predicted values for the Re range of 200 to 1200. The corresponding increase in pressure drop was 7 to 18 times that predicted by conventional theory. C1 Wichita State Univ, Dept Mech Engn, Wichita, KS 67260 USA. Dept Energy, Pacific NW Natl Lab, Richland, WA 99352 USA. RP Wichita State Univ, Dept Mech Engn, Wichita, KS 67260 USA. NR 16 TC 11 Z9 11 U1 2 U2 2 PU BEGELL HOUSE INC PI DANBURY PA 50 NORTH ST, DANBURY, CT 06810 USA SN 1065-5131 EI 1563-5074 J9 J ENHANC HEAT TRANSF JI J. Enhanc. Heat Transf. PY 1999 VL 6 IS 5 BP 383 EP 393 PG 11 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 225MR UT WOS:000081965800005 ER PT J AU Bogner, JE Spokas, KA Burton, EA AF Bogner, JE Spokas, KA Burton, EA TI Temporal variations in greenhouse gas emissions at a midlatitude landfill SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID NITROUS-OXIDE FLUXES; CARBON-DIOXIDE TRANSPORT; METHANE OXIDATION; COVER SOIL; FIELD MEASUREMENT; CH4 AB A field study encompassing a parallel time series of CH4, N2O, and CO2 emissions measurements was completed by using static enclosure techniques at a midlatitude landfill (northeastern Illinois) during the period of July through December 1995. The site had a pumped gas recovery system and thus a high level of engineered gas control. No net CH4 emissions to the atmosphere were measured during this study; rather, the landfill cover soils were functioning as a sink for atmospheric CH4. The net measured emissions of CO2 (dark respiration) and N2O were in ranges characteristic of natural soils and were dependent on similar controls, including temperature, moisture, and aeration status. A comparison of proximal (near gas recovery well) and distal (between wells) emissions with soil gas profiles permitted development of a conceptual biogeochemical model for gas transport and reaction through the landfill cover. This model includes a modified reduction sequence where the major zones (from ground surface downward) were a near-surface zone of optimum CH4 oxidation; a zone of optimum CO2 production (predominantly from root zone respiration); a zone of optimum N2O production; and a deep zone dominated by transport of landfill gas (CH4 and CO2) from methanogenic production zones in the underlying refuse. C1 Univ Illinois, Dept Earth & Environm Sci, Chicago, IL 60607 USA. Landfills Plus Inc, Wheaton, IL 60187 USA. Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. No Illinois Univ, Dept Geol, De Kalb, IL 60155 USA. RP Bogner, JE (reprint author), Univ Illinois, Dept Earth & Environm Sci, Chicago, IL 60607 USA. EM landfill@ix.netcom.com RI Spokas, Kurt/F-4839-2016 OI Spokas, Kurt/0000-0002-5049-5959 NR 38 TC 28 Z9 31 U1 1 U2 12 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 JAN-FEB PY 1999 VL 28 IS 1 BP 278 EP 288 PG 11 WC Environmental Sciences SC Environmental Sciences & Ecology GA 159QJ UT WOS:000078184900034 ER PT J AU Duffy, S Simon, SL Whicker, FW AF Duffy, S Simon, SL Whicker, FW TI Cs-137 contamination of plants used for traditional medicine and implications for human exposure SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Article DE medicinal plants; traditional medicine; Marshall islands; dose assessment; environmental Cs-137 ID MARSHALL ISLANDS AB This paper discusses the use of medicinal plants in traditional medicine practices in the Marshall Islands and measurement data of Cs-137 in, plants used in medicinal remedies. This previously unexplored contribution to radiation exposure was recognized as one of several potentially important considerations in determining present-day risks to the Marshallese population from residual weapons' test radioactivity in the environment. The leaves or fruit of five species of plants were sampled at 14 of the 29 atolls of the Marshall Islands. Cs-137 concentrations were measured in 295 samples. The concentration of Cs-137 in, each species generally decreased with increasing distance and decreasing latitude from the atomic weapons testing area in the northern area of the country. Of the species sampled, Polypodium scolopendria exhibited the highest mean Cs-137 concentration by several fold. Other species could not be differentiated in terms of Cs-137 uptake. The results of calculations to assess possible radiation doses under specific intake scenarios indicate that at most locations in the Marshall Islands, ingestion of these plants for medicinal purposes will not contribute significantly to the total dose received (above background), although the frequency and amount of consumption of these plants is not well known. This study provides the first information of its kind for the assessment of radiation dose to Marshall Islands' residents from locally grown plants used in traditional medicine. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Air Qual Grp, Los Alamos, NM 87544 USA. RP Duffy, S (reprint author), Univ Calif Los Alamos Natl Lab, Air Qual Grp, ESH-17,MS J978, Los Alamos, NM 87544 USA. NR 27 TC 6 Z9 6 U1 1 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 1999 VL 46 IS 1 BP 27 EP 44 DI 10.1016/S0265-931X(98)00121-0 PG 18 WC Environmental Sciences SC Environmental Sciences & Ecology GA 210TJ UT WOS:000081120500003 ER PT J AU Hinton, TG Bell, CM Whicker, FW Philippi, T AF Hinton, TG Bell, CM Whicker, FW Philippi, T TI Temporal changes and factors influencing Cs-137 concentration in vegetation colonizing an exposed lake bed over a three-year period SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Article ID TO-PLANT TRANSFER; AQUATIC MACROPHYTES; ELEMENT COMPOSITION; ORGANIC-MATTER; SOIL TYPES; RADIOCESIUM; SEDIMENTS; RADIOSTRONTIUM; CONTAMINATION; CESIUM-137 AB Activity concentrations of Cs-137 in sediments, as well as extractable sediment concentrations of K, Na, Mg, Ca, Mn, Zn and P, pH, percent organic matter and cation exchange capacity, were used as independent variables in an incomplete principal component analysis to identify factors affecting Cs-137 activity concentrations in 12 species of native wetland and terrestrial plants invading a recently exposed lake bed. Sediments in the lake had been contaminated 35 years previously from discharges at a nuclear production reactor. Cs-137 activity concentrations in plants were positively correlated with sediment concentrations of Na and Cs-137, and inversely correlated to K and pH. Significant decreases in concentrations of sediment constituents (from 3 to 77%), as well as a 42% decline in Cs-137 activity concentrations in plants, occurred during the three-year period. Significant differences in Cs-137 activity concentrations among plant species, driven by low concentrations in cattails (Typha latifolia), were observed. Terrestrial species had significantly lower activity concentrations of Cs-137 than species classified as wetland (arithmetic mean +/- S.E. of 1069 +/- 151. and 2602 +/- 394, respectively). Concentration ratios (Bq kg(-1) dry plant/Bq kg(-1) dry soil) were among the highest reported in the literature (arithmetic mean +/- S.D. = 12.5 +/- 28.9; geometric mean = 1.6, geometric S.D. = 1.4) and were attributed to kaolinitic sediments of pH < 5, organic matter < 5%, K concentrations < 15 ppm and cation exchange capacity < 5 meg (100 g(-1)). Even though Cs-137 was released into the system over 35 years ago, lowering of the water caused Cs-137 in the newly formed terrestrial system to behave like a fresh, rather than aged, deposit (initial uptake rates by plants were high and subsequent reductions in bioavailability were rapid). Implications for management of contaminated reservoirs from a public risk perspective are discussed. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Hinton, TG (reprint author), Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. NR 60 TC 14 Z9 14 U1 1 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 1999 VL 44 IS 1 BP 1 EP 19 DI 10.1016/S0265-931X(98)00074-5 PG 19 WC Environmental Sciences SC Environmental Sciences & Ecology GA 175DJ UT WOS:000079077200001 ER PT J AU Garten, CT AF Garten, CT TI Modeling the potential role of a forest ecosystem in phytostabilization and phytoextraction of (90)Sr at a contaminated watershed SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Article DE bioremediation; pollution prevention; radionuclide transport; water pollution; waste management; radioactive wastes AB The behavior of (90)Sr at forest sites in the White Oak Creek watershed, near Oak Ridge, Tennessee, was simulated with a simple, site-specific, multicompartment model that linked biomass and element cycling dynamics. The model was used to predict the role of forest cover in mitigating hydrologic losses of (90)Sr from contaminated soils (i.e. phytostabilization) under conditions where contaminant transport is governed mainly by shallow subsurface flow. The model was also used to predict the removal of (90)Sr from soil (i.e. phytoextraction) through the growth and hal vest of short rotation woody crops over a period of 30 years. Simulations with the model indicated that (1) forest preservation on the watershed is a form of phytostabilization because forest cover helps to minimize hydrologic losses of (90)Sr and (2) an attempt to significantly reduce amounts of (90)Sr in soil through phytoextraction would be unsuccessful. Over a period of 30 years, and under various management strategies, the model predicted that similar to 15% of the (90)Sr initially present in soil at a contaminated site was lost through hydrologic transport and similar to 53% was lost by radioactive decay, Phytostabilization may be important in the management of radioactive land when issues like waste minimization and pollution prevention affect the selection of technologies to be used in environmental restoration. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Ecol Sci Sect, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Garten, CT (reprint author), Oak Ridge Natl Lab, Ecol Sci Sect, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. EM ctga@ornl.gor NR 29 TC 11 Z9 13 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 1999 VL 43 IS 3 BP 305 EP 323 DI 10.1016/S0265-931X(98)00061-7 PG 19 WC Environmental Sciences SC Environmental Sciences & Ecology GA 170RD UT WOS:000078819100005 ER PT J AU Fresquez, PR Kraig, DH Mullen, MA Naranjo, L AF Fresquez, PR Kraig, DH Mullen, MA Naranjo, L TI Radionuclides and trace elements in fish collected upstream and downstream of Los Alamos National Laboratory and the doses to humans from the consumption of muscle and bone SO JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART B-PESTICIDES FOOD CONTAMINANTS AND AGRICULTURAL WASTES LA English DT Article DE Am; Cs; Hg; Pu; Sr; U; contamination; translocation; exposure; risk ID MERCURY AB The purpose of this study was to determine radionuclide and trace element concentrations in bottom-feeding fish (catftsh, carp, and suckers) collected from the confluences of some of the major canyons that cross Los Alamos National Laboratory (LANL) lands with the Rio Grande (RG) and the potential radiological doses from the ingestion of these fish. Samples of muscle and bone (and viscera in some cases) were analyzed for H-3 Sr-90,Cs-137, U-tot, Pu-238, Pu-239,Pu-240, and Am-241 and Ag, As, Ba, Be, Cr, Cd, Cu, Hg, Ni, Pb, Sb, Se, and Tl. Most radionuclides, with the exception of Sr-90, in the muscle plus bone portions of fish collected from LANL canyons/RG were not significantly (p<0.05) higher from fish collected upstream (San Ildefonso/background) of LANL. Strontium-90 in fish muscle plus bone tissue significantly (p<0.05) increases in concentration starting from Los Alamos Canyon, the most upstream confluence (fish contained 3.4E-02 pCi g(-1) [126E-02 Bq kg(-1)]), to Frijoles Canyon, the most downstream confluence (fish contained 14E-02 pCi g(-1) [518B-02 Bq kg(-1)]). The differences in Sr-90 concentrations in fish collected downstream and upstream (background) of LANL, however, were very small. Based on the average concentrations (+/-2SD) of radionuclides in fish tissue from the four LANL confluences, the committed effective dose equivalent from the ingestion of 46 Ib (21 kg) (maximum ingestion rate per person per year) of fish muscle plus bone, after the subtraction of background, was 0.1 +/- 0.1 mrem y(-1) (1.0 +/- 1.0 mu Sv y(-1)), and was far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem y(-1) (1000 mu Sv y(-1)). Of the trace elements that were found above the limits of detection (Ba, Cu, and Hg) in fish muscle collected from the confluences of canyons that cross LANL and the RG, none were in significantly higher (p<0.05) concentrations than in muscle of fish collected from background locations. C1 Univ Calif Los Alamos Natl Lab, Environm Safety & Hlth Div, Los Alamos, NM 87545 USA. RP Fresquez, PR (reprint author), Univ Calif Los Alamos Natl Lab, Environm Safety & Hlth Div, M887, Los Alamos, NM 87545 USA. NR 40 TC 3 Z9 3 U1 1 U2 6 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0360-1234 J9 J ENVIRON SCI HEAL B JI J. Environ. Sci. Health Part B-Pestic. Contam. Agric. Wastes PY 1999 VL 34 IS 5 BP 885 EP 899 DI 10.1080/03601239909373233 PG 15 WC Environmental Sciences; Public, Environmental & Occupational Health SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health GA 230DM UT WOS:000082236600010 PM 10466108 ER PT J AU Fresquez, PR Biggs, JR Bennett, KD Kraig, DH Mullen, MA Ferenbaugh, JK AF Fresquez, PR Biggs, JR Bennett, KD Kraig, DH Mullen, MA Ferenbaugh, JK TI Radionuclides in deer and elk from Los Alamos National Laboratory and the doses to humans from the ingestion of muscle and bone SO JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART B-PESTICIDES FOOD CONTAMINANTS AND AGRICULTURAL WASTES LA English DT Article DE Pu; Cs; Sr; Am; U; contamination; translocation; exposure; risk ID SOILS AB This paper summarizes radionuclide concentrations (H-3, Sr-90, Cs-137, Pu-238, Pu-239,Pu-240, Am-241, and U-tot), muscle and bone tissue of mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus) collected from Los Alamos National Laboratory (LANL), Los Alamos, New Mexico, lands from 1991 through 1998. Also, the committed effective dose equivalent (CEDE) and the risk of excess cancer fatalities (RECF) to people who ingest muscle and bone from deer and elk collected from LANL lands were estimated. Most radionuclide concentrations in muscle and bone from individual deer (n = 11) and elk (n = 22) collected from LANL lands were either at less than detectable quantities (where the analytical result was smaller than two counting uncertainties) and/or within upper (95%) level background (BG) concentrations. As a group, most radionuclides in muscle and bone of deer and elk from LANL lands were not significantly higher (p<0.10) than in similar tissues from deer (n = 3) and elk (n = 7) collected From BG locations. Also, elk that had been radio collared and tracked for two years and spent an average time of 50% on LANL lands were not significantly different in most radionuclides from road kill elk that have been collected as part of the environmental surveillance program. Overall, the upper (95%) level net CEDEs (the CEDE plus two sigma for each radioisotope minus background) at the most conservative ingestion rate (50 Ibs of muscle and 13 Ibs of bone) were as follows: deer muscle = 0.22 mrem y(-1) (2.2 mu Sv y(-1)), deer bone = 3.8 mrem y(-1) (38 mu Sv y(-1)), elk muscle = 0.12 mrem y(-1) (1.2 mu Sv y(-1)), and elk bone = 1.7 mrem y(-1) (17 mu Sv y(-1)). Al CEDEs were far below the International Commission on Radiological Protection guideline of 100 mrem y(-1) (1000 mu Sv y(-1)), and the highest muscle plus bone net CEDE corresponded to a RECF of 2E-06, which is far below the Environmental Protection Agency upper level guideline of 1E-04. C1 Univ Calif Los Alamos Natl Lab, Environm Safety & Hlth Div, Los Alamos, NM 87545 USA. RP Fresquez, PR (reprint author), Univ Calif Los Alamos Natl Lab, Environm Safety & Hlth Div, POB 1663,M887, Los Alamos, NM 87545 USA. RI Bennett, Keith/C-8619-2009 OI Bennett, Keith/0000-0002-3423-1531 NR 41 TC 2 Z9 2 U1 0 U2 3 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0360-1234 J9 J ENVIRON SCI HEAL B JI J. Environ. Sci. Health Part B-Pestic. Contam. Agric. Wastes PY 1999 VL 34 IS 5 BP 901 EP 915 DI 10.1080/03601239909373234 PG 15 WC Environmental Sciences; Public, Environmental & Occupational Health SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health GA 230DM UT WOS:000082236600011 PM 10466109 ER PT J AU Ozhogin, VI Babushkina, NA Belova, LM Zhernov, AP Haller, EE Itoh, KM AF Ozhogin, VI Babushkina, NA Belova, LM Zhernov, AP Haller, EE Itoh, KM TI Isotope effect for the thermal expansion coefficient of germanium SO JOURNAL OF EXPERIMENTAL AND THEORETICAL PHYSICS LA English DT Article ID CONDUCTIVITY; CRYSTALS; MODEL; SI; GE AB The first experimental and theoretical investigation of the difference in the temperature behavior of the linear expansion coefficients of single crystals grown from isotopically highly enriched and natural germanium is reported. A comparison of the data for Ge-70 and Ge-nat crystals reveals the significant influence of isotopic composition over a wide range of temperatures 30-230 K. (C) 1999 American Institute of Physics. [S1063-7761(99)02101-0]. C1 Kurchatov Inst Russian Sci Ctr, Inst Mol Phys, Moscow 123182, Russia. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Keio Univ, Dept Appl Phys, Yokohama, Kanagawa 2238522, Japan. RP Ozhogin, VI (reprint author), Kurchatov Inst Russian Sci Ctr, Inst Mol Phys, Moscow 123182, Russia. RI Belova, Lyubov/A-9868-2011; Itoh, Kohei/C-5738-2014 OI Belova, Lyubov/0000-0003-4889-4210; NR 10 TC 7 Z9 7 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1063-7761 J9 J EXP THEOR PHYS+ JI J. Exp. Theor. Phys. PD JAN PY 1999 VL 88 IS 1 BP 135 EP 137 DI 10.1134/1.558775 PG 3 WC Physics, Multidisciplinary SC Physics GA 173ZL UT WOS:000079009600021 ER PT J AU Su, YJ Caton, RG Horwitz, JL Richards, PG AF Su, YJ Caton, RG Horwitz, JL Richards, PG TI Systematic modeling of soft-electron precipitation effects on high-latitude F region and topside ionospheric upflows SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID X-B CONVECTION; ION; ALTITUDE; EISCAT; FIELD AB An ionospheric plasma fluid transport model is used tp investigate the effects of soft (<1 keV) electron precipitation on high-latitude F region/topside ionospheric O+ upflows. In this paper we present a systematic modeling study of ionospheric effects of varying soft-electron precipitation, focusing on the resulting upward O+ ion velocities and fluxes, as well as the elevated ion and electron temperatures, due to the precipitation. Recent satellite observations [Seo et al., 1997] suggest an inverse relationship between upward O+ fluxes and the characteristic energy of the precipitating electrons for the same energy flux level. The modeling. results presented here show this inverse relationship explicitly. Our interpretation is that a declining characteristic energy at constant energy flux increases the number of precipitating electrons available to heat the thermal electrons, and thus enhances the thermal electron temperature and hence the ambipolar electric field for propelling the upward O+ flows. The modeled increase of the thermal electron temperature with enhanced auroral electron precipitation is also generally consistent with the Seo et al. [1997] topside ionospheric plasma measurements. In addition, the modeling results presented here illustrate characteristic temporal development responses, showing dramatic increases in velocity, Mach number, and flux values during the first 10-13 min after the precipitation is turned on. By similar to 1 hour after the initiation of a soft-electron precipitation event the ion upward velocities and fluxes approach nearly stable, asymptotic values. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Radex Inc, Bedford, MA 01730 USA. Univ Alabama, Ctr Space Plasma & Aeronom Res, Huntsville, AL 35899 USA. RP Su, YJ (reprint author), Univ Calif Los Alamos Natl Lab, NIS-1,MS D466, Los Alamos, NM 87545 USA. EM ysu@lanl.gov; caton@ziggy.radex.plh.af.mil; witzj@cspar.uah.edu; richards@cs.uah.edu NR 22 TC 37 Z9 38 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 JAN 1 PY 1999 VL 104 IS A1 BP 153 EP 163 DI 10.1029/1998JA900068 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158LB UT WOS:000078116000012 ER PT J AU Le, G Gosling, JT Russell, CT Elphic, RC Thomsen, MF Newbury, JA AF Le, G Gosling, JT Russell, CT Elphic, RC Thomsen, MF Newbury, JA TI The magnetic and plasma structure of flux transfer events SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ACCELERATED FLOW EVENTS; DAYSIDE MAGNETOPAUSE; EARTHS MAGNETOPAUSE; RECONNECTION; FIELD; ISEE-1; MAGNETOSPHERE; MAGNETOMETERS; SIGNATURE; ION AB Flux transfer events have been interpreted to be manifestations of transient reconnection of the magnetospheric and magnetosheath magnetic fields at the Earth's magnetopause. In this study we determine the interior structure of flux transfer events by examining high-resolution magnetic field and plasma distribution functions from the ISEE 2 spacecraft. The sampling time and cadence of these data are more than adequate tb resolve the rapidly changing plasma regimes and to avoid spatial aliasing. From these data we have confirmed the existence of two distinct legions within a flux transfer event (FTE), a central core and a field-draping region, and these two regions have been found within FTEs observed both on the magnetosheath side and the magnetospheric side of the magnetopause. The boundaries between the two regions are apparent in both the field and the plasma data. In the field-draping region the plasma distribution functions show little difference from those in the neighboring magnetosheath or magnetosphere, and the magnetic field consistently exhibits signatures expected from field-line draping around a flux tube. Within the central core region, plasma appears to be a mixture of the magnetosheath and magnetospheric components. In FTEs observed in the magnetosphere, we find transmitted magnetosheath plasma and a strong depletion of hot magnetospheric plasma. In FTEs observed in the magnetosheath, we find an outflow of magnetospheric plasma mixed with the magnetosheath plasma. These signatures unambiguously show the reconnection of the interplanetary magnetic field and the Earth's magnetic field. Thus our observations indicate that the magnetic field lines within the central core region are open allowing the inflow of cold magnetosheath plasma and the outflow of hot magnetospheric plasma through the open flux tube. The reconnection picture is further supported by the observation of separate electron and ion edges at the trailing boundary of a northward moving flux tube, expected as time-of-flight effects on newly reconnected field lines. Thus our observations are consistent with the reconnected open flux tube interpretation for FTEs. C1 Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Le, G (reprint author), Univ Calif Los Angeles, Inst Geophys & Planetary Phys, 405 Hilgard Ave, Los Angeles, CA 90095 USA. RI Le, Guan/C-9524-2012; OI Le, Guan/0000-0002-9504-5214; Russell, Christopher/0000-0003-1639-8298 NR 35 TC 14 Z9 14 U1 0 U2 6 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 JAN 1 PY 1999 VL 104 IS A1 BP 233 EP 245 DI 10.1029/1998JA900023 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158LB UT WOS:000078116000019 ER PT J AU Fairfield, DH Mukai, T Brittnacher, M Reeves, GD Kokubun, S Parks, GK Nagai, T Matsumoto, H Hashimoto, K Gurnett, DA Yamamoto, T AF Fairfield, DH Mukai, T Brittnacher, M Reeves, GD Kokubun, S Parks, GK Nagai, T Matsumoto, H Hashimoto, K Gurnett, DA Yamamoto, T TI Earthward flow bursts in the inner magnetotail and their relation to auroral brightenings, AKR intensifications, geosynchronous particle injections and magnetic activity SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID KILOMETRIC RADIATION; CURRENT DISRUPTION; MAGNETOSPHERE; DYNAMICS; MODELS; SHEET; FIELD AB High-velocity magnetotail flow bursts measured by the Geotail Low Energy Plasma experiment in the premidnight equatorial region between 10 and 15 R-E have been compared with other magnetospheric phenomena. These bursts, typically characterized by earthward velocities approaching 1000 km/s and lasting for times of the order of 1 min, are associated with magnetotail dipolarizations and large magnetic field fluctuations. Using supporting measurements of the International Solar Terrestrial Physics program it is found that the flow bursts are closely associated with auroral brightenings, AKR onsets, geosynchronous particle injections, and ground magnetic activity. Flow bursts for which Polar UVI images are available showed auroral brightenings that developed near the footpoint Geotail field line. AKR intensifications usually accompanied the flow bursts in close time coincidence, whereas dispersionless geosynchronous particle injections tended to be delayed by 1-3 min. Since flow bursts often exhibit the earliest onsets of these various phenomena, it seems likely that this chain of events is initiated in the tail beyond 15 RE, presumably by magnetic reconnection. It is concluded that flow bursts are a fundamental magnetotail process of limited spacial extent that are important in energy and magnetic flux transport in the magnetosphere. Magnetotail flow bursts are intimately connected to auroral acceleration processes and AKR generation at several thousand kilometer altitude and a full explanation of substorms will have to explain this relationship. C1 NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Univ Washington, Geophys Program, Seattle, WA 98195 USA. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Nagoya Univ, STELAB, Toyokawa 442, Japan. Kyoto Univ, Ctr Radio Atmospher Sci, Uji, Kyoto 611, Japan. ISAS, Sagamihara, Kanagawa 229, Japan. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Tokyo Inst Technol, Tokyo 152, Japan. RP Fairfield, DH (reprint author), NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Code 695, Greenbelt, MD 20771 USA. EM u2dhf@lepdhf.gsfc.nasa.gov; mukai@fujitubo.gtl.isas.ac.jp; brib@geophys.washington.edu; reeves@lanl.gov; kokubun@stelab.nagoya-u.ac.jp; parks@geophys.washington.edu; matsumot@kurasc.kyoto-u.ac.jp; kozo@kurasc.kyoto-u.ac.jp; gurnett@space.physics.uiowa.edu RI Reeves, Geoffrey/E-8101-2011 OI Reeves, Geoffrey/0000-0002-7985-8098 NR 35 TC 115 Z9 116 U1 1 U2 4 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 JAN 1 PY 1999 VL 104 IS A1 BP 355 EP 370 DI 10.1029/98JA02661 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158LB UT WOS:000078116000028 ER PT J AU Cheng, CZ Johnson, JR AF Cheng, CZ Johnson, JR TI A kinetic-fluid model SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ALFVEN WAVES; PLASMAS; MAGNETOSPHERE; EQUATIONS; TRANSPORT AB A nonlinear kinetic-fluid model for high beta plasmas with multiple ion species which can be applied to multiscale phenomena is presented. The model embeds important kinetic effects due to finite ion Larmor radius (FLR), wave-particle resonances, magnetic particle trapping, etc., in the framework of simple fluid descriptions. When further restricted to low-frequency phenomena, with frequencies less than the ion cyclotron frequency, the kinetic-fluid model takes a simpler form in which the fluid equations of multiple ion species collapse into one-fluid density and momentum equations and a low-frequency generalized Ohm's law. The kinetic effects are introduced via plasma pressure tensors for ions and electrons which are computed from particle distribution functions that are governed by the Vlasov equation or simplified plasma dynamics equations such as the gyrokinetic equation. The ion FLR effects provide a finite parallel electric field, a perpendicular velocity that modifies the E x B drift, and a gyroviscosity tensor, all of which are neglected in the usual one-fluid MHD description. Eigenmode equations are derived, which include magnetosphere-ionosphere coupling effects for low-frequency waves (e.g., kinetic/inertial Alfven waves and ballooning-mirror instabilities). C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Cheng, CZ (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Cheng, Chio/K-1005-2014 NR 25 TC 49 Z9 49 U1 1 U2 3 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 JAN 1 PY 1999 VL 104 IS A1 BP 413 EP 427 DI 10.1029/1998JA900065 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158LB UT WOS:000078116000032 ER PT J AU Jordanova, VK Farrugia, CJ Quinn, JM Torbert, RB Borovsky, JE Sheldon, RB Peterson, WK AF Jordanova, VK Farrugia, CJ Quinn, JM Torbert, RB Borovsky, JE Sheldon, RB Peterson, WK TI Simulation of off-equatorial ring current ion spectra measured by Polar for a moderate storm at solar minimum SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MAGNETIC-FIELD; ELECTRON; MISSION; PHASE AB We use our kinetic drift-loss model to study ring current dynamics during moderate geomagnetic activity at the minimum phase of the current solar cycle, on March 20-22, 1996. Interplanetary conditions monitored by Wind during this period show fluctuations about zero in the (GSM) B-z component, which are due to Alfven waves in a stream-stream interaction region. The corresponding Dst index shows general activity punctuated by 2 moderate storms (min Dst approximate to-50 nT and approximate to-70 nT, respectively) of similar to 15 hours duration each. We calculate the off-equatorial ring current proton spectra in the energy range 100 eV to 300 keV and compare them with measurements provided by the HYDRA, TIMAS, and CEPPAD instruments on the Polar spacecraft at MLT approximate to 2 and MLT approximate to 14. We find reasonable overall agreement. An eastward offset of 3 hours in the Kp-dependent Volland-Stern convection electric field with gamma=2 is necessary in order to match modeled with observed dips in the energy spectra. Collisional losses have larger effect on the postnoon spectra and reduce significantly the low-energy proton distribution at low L shells and at higher magnetic latitudes. These losses reach maximum values for slowly drifting (similar to 2-10 keV) particles. Our study suggests that a more realistic magnetospheric electric field and additional diffusion processes should be considered to reduce the overestimated width and depth of the dip in the modeled dayside spectra. C1 Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Lockheed Martin Space Sci Lab, Palo Alto, CA 94304 USA. Boston Univ, Ctr Space Phys, Boston, MA 02215 USA. RP Jordanova, VK (reprint author), Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA. RI Peterson, WK/A-8706-2009; OI Peterson, WK/0000-0002-1513-6096; Jordanova, Vania/0000-0003-0475-8743 NR 17 TC 34 Z9 33 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 JAN 1 PY 1999 VL 104 IS A1 BP 429 EP 436 DI 10.1029/98JA02658 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158LB UT WOS:000078116000033 ER PT J AU Xu, TF Samper, J Ayora, C Manzano, M Custodio, E AF Xu, TF Samper, J Ayora, C Manzano, M Custodio, E TI Modeling of non-isothermal multi-component reactive transport in field scale porous media flow systems SO JOURNAL OF HYDROLOGY LA English DT Article DE reactive transport; multi-component; non-isothermal; variably saturated media; geochemistry; Llobregat Delta ID EQUILIBRIUM CHEMISTRY; SOLUTE TRANSPORT; GROUNDWATER; PRECIPITATION; DISSOLUTION; SIMULATION AB A general 2-D finite element multi-component reactive transport code, TRANQUI, was developed, using a sequential iteration approach (SIA). It is well suited to deal with complex real-world thermo-hydro-geochemical problems for single-phase variably water saturated porous media flow systems. The model considers a wide range of hydrological and thermodynamic as well as chemical processes such as aqueous complexation, acid-base, redox, mineral dissolution/precipitation, gas dissolution/ex-solution, ion exchange and adsorption via surface complexation. Under unsaturated conditions only water flow is considered, although gas pressures are allowed to vary in space in a depth-dependent manner specified by the user. In addition to the fully iterative sequential approach (SIA), a sequential non-iterative approach (SNIA), in which transport and chemistry are de-coupled, was implemented and tested. The accuracy and numerical performance of SIA and SNIA have been compared using several test cases. The accuracy of SNIA depends on space and time discretization as well as on the nature of the chemical reactions. The capability of the code to model a real case study in the field is illustrated by its application to the modeling of the hydrochemical evolution of the Llobregat Delta aquitard in northeastern Spain over the last 3500 years during when fresh-water flow from a lower aquifer displaced the native saline aquitard waters. Manzano and Custodio carried out a reactive transport model of this case study by using the PHREEQM code and considering: water flow, aqueous complexation, cation exchange and calcite dissolution. Their results compare favorably well with measured porewater chemical data, except for some of the cations. Our code is not only able to reproduce the results of previous numerical models, but leads to computed concentrations which are closer to measured data mainly because our model takes into consideration redox processes in addition to the processes mentioned above. A number of sensitivity runs were performed with TRANQUI in order to analyze the effect of errors and uncertainties on cation selectivities. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ A Coruna, Escuela Ingn Caminos Canales & Puertos, La Coruna, Spain. CSIC, Inst Ciencias Tierra, Barcelona, Spain. Univ Politecn Cataluna, Dept Ingn Terreno, E-08028 Barcelona, Spain. RP Xu, TF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Mail Stop 90-1116,1 Cyclotron Rd, Berkeley, CA 94720 USA. EM Tianfu_Xu@lbl.gov RI ayora, carlos/M-3914-2014; Samper, Javier /F-7311-2016 OI ayora, carlos/0000-0003-0238-7723; Samper, Javier /0000-0002-9532-8433 NR 38 TC 97 Z9 100 U1 2 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD JAN PY 1999 VL 214 IS 1-4 BP 144 EP 164 DI 10.1016/S0022-1694(98)00283-2 PG 21 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 168FQ UT WOS:000078681400012 ER PT J AU Macken, C AF Macken, C TI Design and analysis of serial limiting dilution assays with small sample sizes SO JOURNAL OF IMMUNOLOGICAL METHODS LA English DT Article DE serial limiting dilution assay; small sample size; single-hit Poisson model AB We study the design of serial limiting dilution assays (SLDAs) for estimation of effector cell frequency in settings that restrict severely the amount of material available for assay, and for which the assumption of a single-hit Poisson model is reasonable. For different designs (that is, dilution factor, number of dilution levels, and number of replicates at each level), we evaluate maximum likelihood and minimum chi-square estimators, using four quantitative criteria: probability of a non-informative assay (PNI), bias, coefficient of variation (CV), and mean squared error (MSE). Our results are exact, not simulation-based, nor approximations. We found that differences between these two estimators were insubstantial by comparison with the effect on the estimators of the experimental design. Bias was severe in small assays, and could lead, in extremely small designs, to overestimation of effector frequency by as much as 100%. These four criteria provide a rigorous basis for determining the most effective apportionment of total effort among replicates and dilution levels. By increasing the dilution factor and favoring the number of replicates over the number of dilution levels, the PNI is reduced while bias, CV and MSE are increased; and vice versa, Our study is easily extended to estimation of the density of biologically active particles per volume. It can also be extended to alternatives to the single-hit Poisson model for a serial limiting dilution assay. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Santa Fe Inst, Santa Fe, NM 87501 USA. RP Macken, C (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. NR 16 TC 16 Z9 16 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1759 J9 J IMMUNOL METHODS JI J. Immunol. Methods PD JAN 1 PY 1999 VL 222 IS 1-2 BP 13 EP 29 DI 10.1016/S0022-1759(98)00133-1 PG 17 WC Biochemical Research Methods; Immunology SC Biochemistry & Molecular Biology; Immunology GA 155CD UT WOS:000077927600002 PM 10022369 ER PT J AU Laouar, A Collart, FR Chubb, CBH Xie, B Huberman, E AF Laouar, A Collart, FR Chubb, CBH Xie, B Huberman, E TI Interaction between alpha(5)beta(1) integrin and secreted fibronectin is involved in macrophage differentiation of human HL-60 myeloid leukemia cells SO JOURNAL OF IMMUNOLOGY LA English DT Article ID PROTEIN-KINASE-C; COLONY-STIMULATING FACTOR; TYROSINE PHOSPHORYLATION; EXTRACELLULAR-MATRIX; SIGNAL-TRANSDUCTION; RETINOIC ACID; MONOCYTIC CELLS; ADHESION; SYK; EXPRESSION AB We examined the role of fibronectin (FN) and FN-binding integrins in macrophage differentiation. Increased FN and alpha(5)beta(1) integrin gene expression was observed in phorbol 12-myristate 13-acetate PMA-treated HL-60 cells and PMA- or macrophage-CSF-treated blood monocytes before the manifestation of macrophage markers. After treatment of HL-60 cells and monocytes, newly synthesized FN was released and deposited on the dishes. An HL-60 cell variant, HL-525, which is deficient in the protein kinase Cp (PKC-beta) and resistant to PMA-induced differentiation, failed to express FN after PMA treatment. Transfecting HL-525 cells with a PKC-beta expression plasmid restored PMA-induced FN gene expression and macrophage differentiation. Untreated HL-525 cells (which have a high level of the alpha(5)beta(1) integrin) incubated on FN differentiated into macrophages. The percentage of cells having a macrophage phenotype induced by PMA in HL-60 cells, by FN in HL-525 cells, or by either PMA or macrophage-CSF in monocytes was reduced in the presence of mAbs to FN and alpha(5)beta(1) integrin. The integrin-signaling nonreceptor tyrosine kinase, p72(Syk), was activated in PMA-treated HL-60 and FN-treated HL-525 cells. We suggest that macrophage differentiation involves the activation of PKC-beta and expression of extracellular matrix proteins such as FN and the corresponding integrins, alpha(5)beta(1) integrin in particular. The stimulated cells, through the integrins, attach to substrates by binding to the deposited FN. This attachment, in turn, may through integrin signaling activate nonreceptor tyrosine kinases, including p72(Syk), and later lead to expression of other genes involved in evoking the macrophage phenotype. C1 Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, Argonne, IL 60439 USA. RP Huberman, E (reprint author), Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 44 TC 29 Z9 29 U1 0 U2 1 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD JAN 1 PY 1999 VL 162 IS 1 BP 407 EP 414 PG 8 WC Immunology SC Immunology GA 151YK UT WOS:000077748100053 PM 9886414 ER PT J AU Bielicki, JK McCall, MR Forte, TM AF Bielicki, JK McCall, MR Forte, TM TI Apolipoprotein A-I promotes cholesterol release and apolipoprotein E recruitment from THP-1 macrophage-like foam cells SO JOURNAL OF LIPID RESEARCH LA English DT Article DE macrophage-foam cells; cholesterol recruitment; sphingomyelin; apolipoprotein A-I; apolipoprotein E; nascent-HDL assembly ID HIGH-DENSITY-LIPOPROTEIN; CELLULAR LIPID EFFLUX; SMOOTH-MUSCLE CELLS; LIPASE; HDL; DISSOCIATION; EXPRESSION; PARTICLES; SECRETION; DISEASE AB Apolipoprotein E (apoE) is synthesized and secreted by arterial macrophages while apolipoprotein A-I (apoA-I) is present in surrounding interstitial fluids. Both apolipoproteins play important roles in macrophage cholesterol homeostasis by forming lipid complexes (nascent-HDL) with cellular phospholipids (PL) and cholesterol (UC) thereby promoting cholesterol efflux, In this study, we evaluated the relative contributions of apoA-I and endogenously produced apoE in mediating the recruitment of cellular cholesterol, THP-1 human monocytes were differentiated (300 nM phorbol dibutyrate) into macrophages and macrophage-foam cells were generated by cholesterol loading with acetylated LDL (50 mu g protein/ml), ApoA-I (10 mu g/ml) depleted macrophage-foam cell cholesteryl esters by 50% in 24 h, This reduction was accompanied by a significant increase in the UC/PL mole ratio of nascent HDL (UC/PL = 0.80 +/- 0.15) in the medium compared to complexes isolated from macrophages (UC/PL = 0.59 +/- 0.08). Significantly more (70%) nascent-HDL were formed in incubations of apoA-I with macrophage-foam cells than with macrophages. Medium apoE accumulation paralleled the assembly of apoA-I containing nascent HDL where 2- and 4-fold increases were observed with macrophages and macrophage-foam cells, respectively, compared to incubations in the absence of apoA-I, Despite the increase in medium apoE accumulation, a majority (85%) of particles (11, 9, and 7.4 nm in diameter) from macrophages and macrophage-foam cells possessed apoA-I without apoE, ApoA-I plus apoE particles (13-16 nm) were also formed along with a small quantity of apoE-only particles (19-20 nm). The predominance of apoA-I only particles indicates, however, that the assembly of apoA-I-containing nascent-HDL, represents a major metabolic pathway of cellular cholesterol recruitment compared to the endogenous production of apoE. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Life Sci Div 1 213, Berkeley, CA 94720 USA. Oregon State Univ, Linus Pauling Inst Sci & Med, Corvallis, OR 97331 USA. RP Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. FU NHLBI NIH HHS [HL 18574] NR 40 TC 55 Z9 57 U1 0 U2 2 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA SN 0022-2275 EI 1539-7262 J9 J LIPID RES JI J. Lipid Res. PD JAN PY 1999 VL 40 IS 1 BP 85 EP 92 PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 153MB UT WOS:000077835900009 PM 9869653 ER PT J AU Graf, MJ Yip, SK Sauls, JA AF Graf, MJ Yip, SK Sauls, JA TI Thermal conductivity of the accidental degeneracy and enlarged symmetry group models for superconducting UPt3 SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article ID HEAVY-FERMION SUPERCONDUCTORS; D-WAVE SUPERCONDUCTORS; UPPER CRITICAL-FIELD; ORDER-PARAMETER; UNCONVENTIONAL SUPERCONDUCTORS; IMPURITY-SCATTERING; PHASE-DIAGRAM; GAP STRUCTURE; STATES; TRANSPORT AB We present theoretical calculations of the thermal conductivity for the "accidental degeneracy" and "enlarged symmetry group" models that have been proposed to explain the phase diagram of UPt3. The order parameters for these models possess point nodes or cross nodes, reflecting the broken symmetries of the ground state. These broken symmetries lead to robust predictions for the ratio of the low-temperature thermal conductivity for heat flow along the (c) over cap axis and in the basal plane, The anisotropy of the heat current response at low temperatures is determined by the phase space for scattering by impurities. The measured anisotropy ratio, kappa(c)/kappa(b), provides a strong constraint on theoretical models for the ground state order parameter. The accidental degeneracy and enlarged symmetry group models based on no spin-orbit coupling do not account for the thermal conductivity of UPt3. The models for the order parameter that fit the experimental data for the (c) over cap and (b) over cap directions of the heat current are the 2D E-1g and E-2u models, for which the order parameters possess line nodes in the ab-plane and point nodes along the (c) over cap axis, and the A(1g) + E-1g model of Zhitomirsky and Ueda. This model spontaneously breaks rotational symmetry in the ab,plane below T-c2 and predicts a large anisotropy for the ab-plane heat current. C1 Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. RP Graf, MJ (reprint author), Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. RI Yip, Sungkit/F-3422-2015; OI Sauls, James/0000-0002-3619-2572 NR 46 TC 13 Z9 13 U1 0 U2 3 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD JAN PY 1999 VL 114 IS 1-2 BP 257 EP 273 DI 10.1023/A:1021814206687 PG 17 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 157TD UT WOS:000078077000010 ER PT J AU Liu, GK Chen, YH Beitz, JV AF Liu, GK Chen, YH Beitz, JV TI Photon avalanche up-conversion in Ho3+ doped fluoride glasses SO JOURNAL OF LUMINESCENCE LA English DT Article DE photon avalanche; up-conversion; green emission; fluoride glass ID LASER CRYSTALS; ZBLAN FIBER; MECHANISMS; DYNAMICS; IONS AB Photon avalanche-induced up-conversion green emission centered at 545 nm was observed in Ho3+ doped, and Ho3+ Tm3+ co-doped ZrF4-based heavy metal fluoride glasses, when excited near 585 nm, which is off resonance with any ground state absorption bands of either Ho3+ or Tm3+ ions. Analyses of spectral measurements suggest that the 545 nm emission occurs from the S-5(2) and F-5(4) states of Ho3+ that are populated by excited-slate absorption from the I-5(7) State of Ho3+. Multi-channel cross-relaxation processes that efficiently populate the I-5(7) State make the photon avalanche process efficient in this system. The photon avalanche dynamics are discussed in detail by comparing the experimental results from the Ho3+ doped and Ho3+, Tm3+ co-doped samples. Published by Elsevier Science B.V. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Liu, GK (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 31 Z9 31 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2313 J9 J LUMIN JI J. Lumines. PD JAN PY 1999 VL 81 IS 1 BP 7 EP 12 DI 10.1016/S0022-2313(98)00059-3 PG 6 WC Optics SC Optics GA 158VN UT WOS:000078138200002 ER PT J AU Bu, HS Cao, J Xu, SY Zheng, Z Wunderlich, B AF Bu, HS Cao, J Xu, SY Zheng, Z Wunderlich, B TI Multimolecule glasses and crystals of isotactic polystyrene SO JOURNAL OF MACROMOLECULAR SCIENCE-PHYSICS LA English DT Article ID MOLECULE SINGLE-CRYSTALS; POLY(ETHYLENE OXIDE); DILUTE-SOLUTIONS; MELT; MORPHOLOGY AB When spreading dilute solutions of isotactic polystyrene (iPS) on water, it was observed that different concentrations produce different morphologies in the resulting amorphous films. From 10(-1) to 10(-2) wt% solutions, ribbonlike films and circular platelets of multimolecule aggregates were obtained. After isothermal crystallization of these amorphous films, lamellae, incipient spherulites, and single-molecule crystals were observed. The formation of lamellar crystals lying flat on the substrate is an indication of the absence of epitaxy by the substrate, which would require the molecular chains to be in the surface plane and thus yield lamellae normal to the substrate. The dense packing in the center of sheaf-like spherulites is caused by screw-dislocation growth, and it produces structures similar to shish kebabs. It was also observed that the lamellae grown from the center develop secondary growth spirals, causing the branching and splaying of the structure typical for spherulitic growth. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Fudan Univ, Dept Mat Sci, Shanghai 200433, Peoples R China. Chinese Acad Sci, Beijing Lab Electron Microscopy, Beijing 100080, Peoples R China. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 27 TC 4 Z9 4 U1 1 U2 5 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0022-2348 J9 J MACROMOL SCI PHYS JI J. Macromol. Sci.-Phys. PY 1999 VL B38 IS 3 BP 251 EP 262 DI 10.1080/00222349908212429 PG 12 WC Polymer Science SC Polymer Science GA 193DE UT WOS:000080119900007 ER PT J AU Lee, JH Li, X Sammi, MK Springer, CS AF Lee, JH Li, X Sammi, MK Springer, CS TI Using flow relaxography to elucidate flow relaxivity SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article ID RECOVERY FAIR TECHNIQUE; MAGNETIC-RESONANCE; BLOOD-FLOW; NMR; PERFUSION; QUANTIFICATION AB We have investigated the theoretical and experimental linear dependence of the reciprocal of the apparent longitudinal relaxation time [(T-1*)(-1)] of the NMR signal from spins in a flowing fluid on the volume flow rate, F-v, the so-called inflow effect. We refer to the coefficient of this dependence as the longitudinal flow relaxivity, r(1F). A very simple model predicts that, under a range of conditions pertinent to modern flow studies and perfusion imaging experiments, r(1F), is controlled by the volume of the fluid in which the magnetization is perturbed by pulsed RF inversion or saturation, not the detection volume, and that it can be approximated as the reciprocal of half of the inversion volume. Phantom sample experiments, using a new, quantitative approach that we call flow relaxography, confirm the general predictions of this simple model. There are two intriguing implications of these findings for general NMR flow studies as well as for medical applications. It should be possible to vary the value of r(1F) by simply (noninvasively) adjusting the inversion slice thickness, and thus measure the value of (blood (H2O)-H-1, for example) F-v in a vessel without changing F-v, from the resultant varying T-1* values. Also, it should be possible to extrapolate to the intrinsic T-1 value of the fluid signal (as if it were stationary), without altering or stopping the flow. Again, these are quite successful in phantom sample studies. Imaging versions of the flow relaxographic experiments are also possible. The twin goals of how studies in medical MRT are the quantitative discrimination of the signals from flowing and nonflowing spins, and the accurate measurement of the flow rate of the former. (C) 1999 Academic Press. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. RP Lee, JH (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI Lee, Jing-Huei/J-3978-2016; OI Lee, Jing-Huei/0000-0001-9921-7629; Springer, Charles/0000-0002-5966-2135 FU NIGMS NIH HHS [R01 GM032125, R01 GM32125] NR 33 TC 15 Z9 15 U1 0 U2 5 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 JAN PY 1999 VL 136 IS 1 BP 102 EP 113 DI 10.1006/jmre.1998.1629 PG 12 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 162PU UT WOS:000078356600014 PM 9887295 ER PT J AU Hamdeh, HH Barghout, K Ho, JC Shand, PM Miller, LL AF Hamdeh, HH Barghout, K Ho, JC Shand, PM Miller, LL TI A Mossbauer evaluation of cation distribution in titanomagnetites SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE titanomagnetites; cation distribution; spinel; Mossbauer spectroscopy; magnetization ID FE2TIO4 AB Peak area analyses of Mossbauer spectra were used to directly appraise models of cation distribution in synthetic titanomagnetites, TixFe3-xO4(0 < x < 1). For x < 0.30, room-temperature and zero-field data were sufficient for this purpose. At higher Ti concentrations, however, they were inconclusive or ineffective because the Mossbauer signals from Fe ions on both tetrahedral and octahedral sites were inextricable. Instead, Mossbauer spectra were collected at 4.2 K in a 7 T magnetic field. In these spectra, the signal from Fe3+ ions on the tetrahedral sites of the cubic spinels was effectively delineated, and on the basis of its area fraction a new cation distribution is proposed. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Wichita State Univ, Dept Phys, Wichita, KS 67260 USA. Univ No Iowa, Dept Phys, Cedar Falls, IA 50614 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys, Ames, IA 50011 USA. RP Hamdeh, HH (reprint author), Wichita State Univ, Dept Phys, Wichita, KS 67260 USA. EM hamdeh@wsuhub.uc.twsu.edu NR 28 TC 23 Z9 24 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD JAN PY 1999 VL 191 IS 1-2 BP 72 EP 78 DI 10.1016/S0304-8853(98)00340-0 PG 7 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 148FV UT WOS:000077495100010 ER PT J AU Kortright, JB Rice, M Kim, SK Walton, CC Warwick, T AF Kortright, JB Rice, M Kim, SK Walton, CC Warwick, T TI Optics for element-resolved soft X-ray magneto-optical studies SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE magneto-optics; magnetic thin films; magnetic imaging; X-ray spectroscopy ID CIRCULAR-DICHROISM; SYNCHROTRON-RADIATION; PHASE-RETARDATION; POLARIZATION; PERFORMANCE; MULTILAYERS; POLARIMETER; MICROSCOPY; UNDULATOR; DOMAINS AB The status of polarizing optical elements for the vacuum ultraviolet and soft X-ray range extending from roughly 50 to 2000 eV are reviewed, as are some of their emerging applications in magneto;optical studies utilizing synchrotron radiation. The optics include tunable linear polarizers and birefringent phase retarders based on multilayer interference structures, and circular polarizing filters based on magnetic circular dichroism. Magneto-optical capabilities enabled by these optical elements include measurement of Faraday and Kerr rotation spectra and hysteresis loops, and the conversion of linear to circular polarization and helicity switching. Circular polarizers combined with scanning zone plate microscopes yield magnetization contrast in transmission imaging. Examples using these capabilities to study polycrystalline Fe films and Fe/Cr multilayers are given. Resonant soft X-ray magneto-optical spectroscopies are especially relevant to obtaining an understanding of magnetism on a microscopic level in complex materials and nanostructures because their element-specific signals can be larger than in other spectral ranges. Combined with scattering and microscopy techniques these spectroscopies can provide depth sensitive and lateral spatial resolution on the nanometer scale. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. RP Kortright, JB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. EM jbkortright@lbl.gov RI Kim, Sang-Koog/J-4638-2014 NR 39 TC 39 Z9 40 U1 2 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD JAN PY 1999 VL 191 IS 1-2 BP 79 EP 89 DI 10.1016/S0304-8853(98)00344-8 PG 11 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 148FV UT WOS:000077495100011 ER PT J AU Shyamala, G AF Shyamala, G TI Progesterone signaling and mammary gland morphogenesis SO JOURNAL OF MAMMARY GLAND BIOLOGY AND NEOPLASIA LA English DT Article DE mammary glands; progesterone; progesterone receptor; morphogenesis ID KERATINOCYTE GROWTH-FACTOR; STEROID-HORMONE RECEPTORS; HUMAN-BREAST; A-FORM; DUCTAL MORPHOGENESIS; EPITHELIAL-CELLS; GENE-EXPRESSION; MENSTRUAL-CYCLE; E-CADHERIN; IN-VIVO AB Progesterone was identified as a mammogenic hormone several years ago but until now its precise role in mammary development has remained obscure. Recently with the generation of several transgenic mouse models and development of reagents for analysis of progesterone receptor expression, the role of progesterone signaling in mammary development is becoming more clear. The most significant observations to emerge from these studies are (1) progesterone receptors (PR)(4) are present in a heterogeneous manner in the epithelial cells and undetectable in the surrounding fat pad; (2) they are essential for lobuloalveolar and not for ductal morphogenesis; (3) progesterone signaling through progesterone receptors, leading to lobuloalveolar development, is initiated in the epithelium and may occur through paracrine mechanisms; and (4) a regulated expression of the two isoforms of progesterone receptor is critical for maintaining appropriate responsiveness to progesterone and hence, epithelial cell replicative homeostasis. These studies also reveal that the consequences of progesterone signaling through progesterone receptor may depend on the cell context, cell-cell and cell-extracellular matrix interactions, the dynamics of PR turnover and the fate of PR positive cells. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Shyamala, G (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, 1 Cyclotron Rd,Bldg 74, Berkeley, CA 94720 USA. EM shyamala_harris@lbl.gov FU NCI NIH HHS [CA66541] NR 72 TC 51 Z9 52 U1 0 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1083-3021 J9 J MAMMARY GLAND BIOL JI J. Mammary Gland Biol. Neoplasia PD JAN PY 1999 VL 4 IS 1 BP 89 EP 104 DI 10.1023/A:1018760721173 PG 16 WC Oncology; Endocrinology & Metabolism; Physiology SC Oncology; Endocrinology & Metabolism; Physiology GA 181WE UT WOS:000079465200008 PM 10219909 ER PT J AU Harrison, WTA Phillips, MLF Chavez, AV Nenoff, TM AF Harrison, WTA Phillips, MLF Chavez, AV Nenoff, TM TI Syntheses and structures of the open-framework phases (CH3NH3)(3)center dot Zn4O(AsO4)(3) and (CH3NH3)(3)center dot Zn4O(PO4)(3) related to the M3Zn4O(XO4)(3)center dot nH(2)O family SO JOURNAL OF MATERIALS CHEMISTRY LA English DT Article ID ROOM-TEMPERATURE SYNTHESIS; REFINEMENT; ZEOLITE AB The solution-mediated syntheses and single crystal structures of the new open-framework phases (CH3NH3)(3). Zn4O(AsO4)(3) and (CH3NH3)(3). Zn4O(PO4)(3) are reported. These compounds are built up from vertex-sharing three-dimensional "OZn4" + ZnO4 + AsO4/PO4 tetrahedral frameworks encapsulating methylammonium cations in three-dimensional channel systems. These phases are closely related to the zeolite-like M3Zn4O(XO4)(3). nH(2)O family of phases. C1 Univ Aberdeen, Dept Chem, Aberdeen AB24 3UE, Scotland. Gemfire Corp, Palo Alto, CA 94303 USA. Sandia Natl Labs, Catalysis & Chem Technol Dept, Albuquerque, NM 87185 USA. RP Harrison, WTA (reprint author), Univ Aberdeen, Dept Chem, Aberdeen AB24 3UE, Scotland. NR 20 TC 37 Z9 37 U1 0 U2 0 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0959-9428 J9 J MATER CHEM JI J. Mater. Chem. PY 1999 VL 9 IS 12 BP 3087 EP 3092 DI 10.1039/a906009j PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 259YN UT WOS:000083921700022 ER PT J AU Russell, AM Tian, Y Rose, JD Ellis, TW Chumbley, LS AF Russell, AM Tian, Y Rose, JD Ellis, TW Chumbley, LS TI A high specific strength, deformation-processed scandium-titanium composite SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID PLATE-LIKE STRUCTURES; SHAPE INSTABILITIES; INSITU COMPOSITES; NB AB A 59% Sc-41% Ti deformation-processed metal-metal composite was produced by rolling to a true strain of 2.3 at 873 K followed by cold rolling to a total true strain of 3.6. Rolling reduced the original eutectoid microstructure to lamellae of alpha-Sc and alpha-Ti with average lamellar thicknesses of 150 nm (Sc) and 120 nm (Ti). The cold-rolled material had an ultimate tensile strength of 942 MPa and a specific strength of 259 J/g, The Sc matrix was oriented with the [0001] tilted 22 degrees from the sheet normal direction toward the rolling direction, an unusual texture for an HCP metal with a low cia ratio, which suggests Sc may deform primarily by basal slip. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. US Steel Co, Gary, IN 46402 USA. Kulicke & Soffa Ind Inc, Willow Grove, PA 19090 USA. RP Russell, AM (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. OI Russell, Alan/0000-0001-5264-0104 NR 26 TC 2 Z9 2 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD JAN PY 1999 VL 14 IS 1 BP 8 EP 11 DI 10.1557/JMR.1999.0003 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 168PG UT WOS:000078701000003 ER PT J AU Hu, MZC Zielke, JT Lin, JS Byers, CH AF Hu, MZC Zielke, JT Lin, JS Byers, CH TI Small-angle x-ray scattering studies of early-stage colloid formation by thermohydrolytic polymerization of aqueous zirconyl salt solutions SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID HYDROLYSIS; PARTICLES AB Early-stage processes involving the polymerization of zirconium species in aqueous solutions at elevated temperatures (similar to 100 degrees C) as well as colloid formation were studied. Small-angle x-ray scattering (SAXS) data were analyzed via Guinier, "longrods," and Pored plots to determine particle growth kinetics and morphology. Our SAXS data suggest that zirconium tetramers and octamers polymerize into larger clusters and elongated-rod-(or needle)-shaped primary particles, which have a length of a few nanometers and a radius of gyration of cross section between 4 and 5 Angstrom. Cube-shaped particles are aggregates of the needlelike primary particles. The transition from zirconium tetramer to a colloidal sol particle follows a mass-fractal growth (1 < fractal dimension, D < 3). C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hu, MZC (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM 15h@ornl.gov OI Hu, Michael/0000-0001-8461-9684 NR 40 TC 26 Z9 27 U1 1 U2 16 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 JAN PY 1999 VL 14 IS 1 BP 103 EP 113 DI 10.1557/JMR.1999.0017 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA 168PG UT WOS:000078701000017 ER PT J AU Mukundan, R Davies, PK Worrell, WL AF Mukundan, R Davies, PK Worrell, WL TI Preparation and characterization of compounds in the BaBiO3-Ba(Ce1-xGdx)O3-x/2 system SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID PEROVSKITES; BA2BI3+BI5+O6; PB; BI AB The structure, nonstoichiometry, and electrical conductivity of compositions in the BaBiO3-Ba(Ce1-xGdx)O3-x/2 system have been investigated in an attempt to prepare new mixed (ionic-electronic) conducting oxides. The substitution of Bi into Ba(Ce1-xGdx)O3-x/2 decreases the concentration of oxygen-ion vacancies, and the effective negative charge of the Gd dopant is compensated by the mixed valence of Bi (3+, 5+). For low Bi contents a decrease in ionic conductivity decreases the overall conductivity: however, higher levels of Bi introduce significant electronic conductivity, and for Ba(Bi0.5Ce0.5)O-3, sigma(total) approximate to 1 S/cm at 800 degrees C in air. Compositions in the Ba(Bi0.5Ce0.5-xGdx)O-3 pseudobinary system undergo a B-cation order-disorder transformation at 1300-1350 degrees C for x = 0.5 and at approximate to 1250 degrees C for x = 0.4; all other compositions retain a disordered B-site arrangement. While these disordered perovskites exhibit oxygen nonstoichiometry under reducing conditions at elevated temperatures, with the extent of reduction decreasing with increasing Gd content, their ordered counterparts remain close to stoichiometry. The electronic conductivities of this pseudobinary could be fitted to a "band-type" model, and, despite the presence of oxygen vacancies for the lower values of x, no significant ionic conductivity was observed. C1 Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. RP Mukundan, R (reprint author), Univ Calif Los Alamos Natl Lab, Elect Res Grp, MS D429,SM-40,TA-3, Los Alamos, NM 87545 USA. NR 19 TC 1 Z9 1 U1 1 U2 6 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 JAN PY 1999 VL 14 IS 1 BP 124 EP 131 DI 10.1557/JMR.1999.0020 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 168PG UT WOS:000078701000020 ER PT J AU Baskaran, S Lewinsohn, CA Chou, YS Qian, M Stevenson, JW Armstrong, TR AF Baskaran, S Lewinsohn, CA Chou, YS Qian, M Stevenson, JW Armstrong, TR TI Mechanical properties of alkaline earth-doped lanthanum gallate SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID PEROVSKITE-TYPE OXIDE; LAGAO3 PEROVSKITE; CONDUCTOR; ELECTROLYTE AB Lanthanum gallate doped with alkaline earths was prepared from combustion-synthesized powders. Mechanical properties of the doped gallates were evaluated as a function of composition and temperature. The indentation fracture toughness of Sr-substituted gallates was significantly better than the Ca- and Ba-substituted materials, but the toughness of all the doped gallates was significantly lower than yttria-stabilized zirconia, a typical electrolyte material. Small improvements in room temperature toughness and strength were measured in (La0.9Sr0.1)(x)Ga0.8Mg0.O-2(3-delta), ("LSGM-1020") samples with significant A-site cation non-stoichiometry (x = 0.9). The flexural strength of stoichiometric LSGM-1020 decreased from approximate to 150 MPa at room temperature, to approximate to 100 MPa at higher temperatures (600-1000 degrees C). The notched-beam fracture toughness of LSGM-1020 decreased from approximate to 2.0-2.2 MPa root m at room temperature, to approximate to 1.0 MPa root m at 600 degrees C. The decrease in mechanical properties over this temperature range was correlated to changes in crystal structure that have been identified by neutron diffraction. These crystallographic changes were also accompanied by significant changes in the thermal expansion behavior and elastic modulus. For off-stoichiometric LSGM-1020 with A/B cation stoichiometry of 0.90, strength and toughness also decreased with temperature, but the retained toughness (approximate to 1.5 MPa root m) at elevated temperatures was higher than the toughness of the stoichiometric LSGM material. (C) 1999 Kluwer Academic Publishers. C1 Pacific NW Lab, Dept Chem & Mat Sci, Richland, WA 99352 USA. RP Baskaran, S (reprint author), Pacific NW Lab, Dept Chem & Mat Sci, POB 999,MS K2-44, Richland, WA 99352 USA. NR 37 TC 29 Z9 29 U1 0 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PY 1999 VL 34 IS 16 BP 3913 EP 3922 DI 10.1023/A:1004683025114 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 223DM UT WOS:000081825100010 ER PT J AU Gladysz, GM Schmucker, M Schneider, H Chawla, KK Joslin, DL Ferber, MK AF Gladysz, GM Schmucker, M Schneider, H Chawla, KK Joslin, DL Ferber, MK TI Preliminary studies in the processing and characterization of Al2O3/SnO2 laminated composites SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID ALUMINA; MONAZITE AB All oxide composites (reinforcement and matrix both being oxides) exhibit high temperature oxidation resistance in addition to high strength and hardness. A major drawback of these materials is that the oxide fiber and oxide matrix tend to react, which strengthens the interface and therefore drastically reduces the damage tolerance. To overcome this problem, a mechanically weak interphase material, which also serves as a diffusion barrier, is generally used. One such materials system is tin dioxide (SnO2) in alumina-based composites. Previous attempts to fabricate such alumina matrix composites have been unsuccessful due to the higher temperatures needed to densify Al2O3 coupled with the fact that SnO2 decomposes to SnO in reducing environments. SnO has a relatively low melting point (1125 degrees C). In this paper we report the successful fabrication of Al2O3/SnO2, laminated composites and some observations on microstructural and mechanical characterization of the laminates. As expected from the phase diagram, no chemical compound formation was observed between Al2O3 and SnO2 which means that no primary chemical bonding developed between individual laminae. TEM observations showed, however, a strong mechanical interlocking at the SnO2/Al2O3 interfaces. In spite of the relatively strong interfacial bond, cracks did deflect. Our microstructural studies showed that SnO2 served as a weak interphase material. (C) 1999 Kluwer Academic Publishers. C1 Univ Calif Los Alamos Natl Lab, ESA, WMM MS C930, Los Alamos, NM 87545 USA. German Aerosp Res Estab, Mat Res Inst, D-51140 Cologne, Germany. Univ Alabama, Dept Mech & Mat Engn, Birmingham, AL 35294 USA. Oxford Instruments Inc, Microanal Grp, Fremont, CA USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Gladysz, GM (reprint author), Univ Calif Los Alamos Natl Lab, ESA, WMM MS C930, POB 1663, Los Alamos, NM 87545 USA. NR 8 TC 3 Z9 4 U1 0 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PY 1999 VL 34 IS 17 BP 4351 EP 4355 DI 10.1023/A:1004600213458 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 223DY UT WOS:000081826200035 ER PT J AU Lin, HT Waters, S Breder, K AF Lin, HT Waters, S Breder, K TI High-temperature creep response of a commercial grade siliconized silicon carbide SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID DAMAGE-ENHANCED CREEP; BEHAVIOR AB Creep studies conducted in four-point flexure of a commercial siliconized silicon carbide (Si-SiC, designated as Norton NT230) have been carried out at temperatures of 1300, 1370, and 1410 degrees C in air under selected stress levels. The Si-SiC material investigated contained similar to 90% alpha-SiC, 8% discontinuous free Si, and 2% porosity. In general, the Si-SiC material exhibited very low creep rates (2 to 10 x 10(-10) s(-1)) at temperatures less than or equal to 1370 degrees C under applied stress levels of up to 300 MPa. At 1410 degrees C, the melting point of Si, the Si-SiC material still showed relative low creep rates (similar to 0.8 to 3 x 10(-9) s(-1)) at stresses below a threshold value of similar to 190 MPa. At stresses > 190 MPa the Si-SiC material exhibited high creep rates plus a high stress exponent (n = 17) as a result of slow crack growth assisted process that initiated within Si-rich regions. The Si-SiC material, tested at temperature less than or equal to 1370 degrees C and below the threshold of 190 MPa at 1410 degrees C, exhibited a stress exponent of one, suggestive of diffusional creep processes. Scanning electron microscopy observations showed very limited creep cavitation at free Si pockets, suggesting the discontinuous Si phase played no or little role in controlling the creep response of the Si-SiC material when it was tested in the creep-controlled regime. (C) 1999 Kluwer Academic Publishers. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Lin, HT (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 20 TC 0 Z9 0 U1 0 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PY 1999 VL 34 IS 18 BP 4393 EP 4398 DI 10.1023/A:1004616617093 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 228FD UT WOS:000082125700004 ER PT J AU Hecht, RL Dinwiddie, RB Wang, H AF Hecht, RL Dinwiddie, RB Wang, H TI The effect of graphite flake morphology on the thermal diffusivity of gray cast irons used for automotive brake discs SO JOURNAL OF MATERIALS SCIENCE LA English DT Article AB Thermal diffusivity of automotive grade SAE G3000 (d) gray cast iron has been measured as a function of graphite flake morphology, chemical composition and temperature. Cast iron samples used for this investigation were cut from "step block" castings designed to produce iron with different graphite flake morphologies resulting from different cooling rates. Samples were also machined from prototype and commercial brake rotors, as well as from a series of cast iron slugs with slightly varying compositions. Thermal diffusivity was measured at room and elevated temperatures via the flash technique. Graphite flake morphology of the various cast iron samples was quantified stereologically with image analysis techniques. Several geometric features of the graphite flake morphology were quantified. It was found that the thermal diffusivity of these gray cast irons increases with carbon equivalent and has a strong linear correlation to graphite flake length. For gray iron with the same chemical composition, a four fold increase in the graphite flake size results in a 50% increase in thermal diffusivity. Amongst the commercial rotors, room temperature thermal diffusivity varied from 0.156 to 0.200 cm(2)/s. (C) 1999 Kluwer Academic Publishers. C1 Ford Motor Co, Res Lab, Vehicle Safety Res Dept, Dearborn, MI 48121 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Hecht, RL (reprint author), Ford Motor Co, Res Lab, Vehicle Safety Res Dept, Dearborn, MI 48121 USA. RI Wang, Hsin/A-1942-2013 OI Wang, Hsin/0000-0003-2426-9867 NR 13 TC 15 Z9 17 U1 0 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PY 1999 VL 34 IS 19 BP 4775 EP 4781 DI 10.1023/A:1004643322951 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 229HM UT WOS:000082188000017 ER PT J AU Hoffman, DK Wei, GW Kouri, DJ AF Hoffman, DK Wei, GW Kouri, DJ TI A variational approach to the Dirichlet-Gabor wavelet-distributed approximating functional SO JOURNAL OF MATHEMATICAL CHEMISTRY LA English DT Article ID FOKKER-PLANCK EQUATION AB We show that the Dirichlet-Gabor wavelet-distributed approximating functional (DAF) can be derived from the same variational principle used to obtain non-interpolating wavelet-DAFs (such as the Hermite DAF). This variational approach for such interpolating DAFs complements the original viewpoint that they are generated by regularizing interpolating shells or through two-parameter Dirac delta sequences. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Natl Univ Singapore, Dept Computat Sci, Singapore 119260, Singapore. Univ Houston, Dept Chem, Houston, TX 77204 USA. Univ Houston, Dept Phys, Houston, TX 77204 USA. RP Hoffman, DK (reprint author), Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RI Wei, Guowei /E-1852-2011 NR 15 TC 5 Z9 5 U1 0 U2 0 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0259-9791 J9 J MATH CHEM JI J. Math. Chem. PY 1999 VL 25 IS 2-3 BP 235 EP 244 DI 10.1023/A:1019140602004 PG 10 WC Chemistry, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Chemistry; Mathematics GA 245LM UT WOS:000083110100007 ER PT J AU Wei, J Lee, CS Lazar, IM Lee, ML AF Wei, J Lee, CS Lazar, IM Lee, ML TI Capillary isoelectric focusing electrospray ionization time-of-flight mass spectrometry for protein analysis SO JOURNAL OF MICROCOLUMN SEPARATIONS LA English DT Article DE capillary isoelectric focusing; electrospray ionization; time-of-flight mass spectrometry ID HEMOGLOBIN-VARIANTS; ELECTROPHORESIS; SEPARATIONS; TRANSFERRIN; DETECTOR AB On-line capillary isoelectric focusing (CIEF)-electrospray ionization time-of-flight mass spectrometry (ESI-TOFMS) as a two-dimensional separation system is employed for high-resolution analysis of model proteins (myoglobin and beta-lactoglobulin) and human hemoglobin variants C, S, F, and A. The focused proteins in a polyacrylamide-coated capillary are mobilized by replacing the sodium hydroxide catholyte with a sheath liquid solution containing methanol-water-acetic acid in a volume ratio of 80:19:1. The use of sheath liquid also establishes the electrical connection at the CIEF capillary terminus, which serves to define the electric field along the CLEF capillary and apply an electric voltage for electrospray ionization. At the end of the CIEF capillary, the mobilized protein zones are analyzed and directly identified by ESI-TOFMS. The TOFMS accumulates spectra at 5000 Hz frequency and one averaged spectrum is acquired per second during the CIEF-ESI-TOFMS measurements. (C) 1999 John Wiley & Sons, Inc. C1 Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Brigham Young Univ, Dept Chem & Biochem, Provo, UT 84602 USA. RP Lee, CS (reprint author), Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. OI Lazar, Iulia/0000-0001-7746-7889 NR 20 TC 10 Z9 10 U1 1 U2 4 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1040-7685 J9 J MICROCOLUMN SEP JI J. Microcolumn Sep. PY 1999 VL 11 IS 3 BP 193 EP 197 DI 10.1002/(SICI)1520-667X(1999)11:3<193::AID-MCS4>3.0.CO;2-Y PG 5 WC Chemistry, Analytical SC Chemistry GA 168CK UT WOS:000078673100004 ER PT J AU Culbertson, CT Jorgenson, JW AF Culbertson, CT Jorgenson, JW TI Lowering the UV absorbance detection limit and increasing the sensitivity of capillary electrophoresis using a dual linear photodiode array detector and signal averaging SO JOURNAL OF MICROCOLUMN SEPARATIONS LA English DT Article ID ABSORBENCY DETECTION; ABSORPTION DETECTION; CELL AB We have recently described a new spatial signal-averaging approach to improve the UV absorbance detection limits for capillary electrophoresis (CE) using a single photodiode array (PDA) detector. (Culbertson, C. T.; Jorgenson, J. W. Anal Chem 1998 70, 2629: Culbertson, C. T. PhD Dissertation, University of North Carolina, Chapel Kill, 1996). At low analyte concentrations, however, source flicker noise interfered with the signal-averaging process. This noise was due to inadequate compensation of the spatial and temporal lamp fluctuations that occurred over the course of a run in this single-beam instrument. To better compensate for the source lamp fluctuations and drift, a double-beam detector has been constructed using a dual PDA to continuously monitor the output of the source. The addition of the reference channel significantly reduces the source flicker noise. To demonstrate the capabilities of this new detector, separations of four nucleic acids at six different concentrations were performed. The signal-averaged electropherograms generated using the double-beam instrument are compared with electropherograms obtained from individual diodes in the array, a single-beam detector, and a commercial single-point detector. The detection limits for the double-beam instrument were 35(+/- 3) times better than that obtained using an individual diode in the array, ca. 4 times better than that obtained using a single-beam detector, and 6.3(+/- 0.4) times better than that obtained using a commercial single-point detector. The linearity of the new detector is found to be equal to or better than that of the commercial single-point detector, and a separation of analytes at mixed concentrations corresponding to a two order of magnitude dynamic range is shown. (C) 1999 John Wiley & Sons, Inc. C1 Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA. RP Jorgenson, JW (reprint author), Oak Ridge Natl Lab, POB 2008,MS6142, Oak Ridge, TN 37831 USA. OI Culbertson, Christopher/0000-0002-6833-3237 NR 15 TC 12 Z9 12 U1 0 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1040-7685 J9 J MICROCOLUMN SEP JI J. Microcolumn Sep. PY 1999 VL 11 IS 9 BP 652 EP 662 DI 10.1002/(SICI)1520-667X(199911)11:9<652::AID-MCS3>3.0.CO;2-7 PG 11 WC Chemistry, Analytical SC Chemistry GA 250YM UT WOS:000083417900003 ER PT J AU Inouye, H Tsuruta, H Sedzik, J Uyemura, K Kirschner, DA AF Inouye, H Tsuruta, H Sedzik, J Uyemura, K Kirschner, DA TI Full sequence P0 myelin glycoprotein: Synchrotron X-ray scattering reveals tetrameric assembly SO JOURNAL OF NEUROCHEMISTRY LA English DT Meeting Abstract C1 Boston Coll, Dept Biol, Chestnut Hill, MA 02467 USA. Stanford Univ, Stanford Linear Accelerator Ctr, SSRL, Stanford, CA 94309 USA. Keio Univ, Sch Med, Dept Physiol, Shinjuku Ku, Tokyo 160, Japan. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0022-3042 J9 J NEUROCHEM JI J. Neurochem. PY 1999 VL 72 SU S BP S15 EP S15 PG 1 WC Biochemistry & Molecular Biology; Neurosciences SC Biochemistry & Molecular Biology; Neurosciences & Neurology GA 167YQ UT WOS:000078663100060 ER PT J AU Subramaniam, S AF Subramaniam, S TI Minimum error Fickian diffusion coefficients for mass diffusion in multicomponent gas mixtures SO JOURNAL OF NON-EQUILIBRIUM THERMODYNAMICS LA English DT Article ID EFFECTIVE BINARY DIFFUSION; CONSISTENT AB Mass diffusion in multicomponent gas mixtures is governed by a coupled system of linear equations for the diffusive mass fluxes in terms of thermodynamic driving forces, known as the generalized Stefan-Maxwell equation. In computations of mass diffusion in multicomponent gas mixtures, this coupling between the different components results in considerable computational overhead. Consequently, simplified diffusion models for the diffusive mass fluxes as explicit functions of the driving forces are an attractive alternative. These models can be interpreted as an approximate solution to the Stefan-Maxwell equation. Simplified diffusion models require the specification of "effective" diffusion coefficients which are usually expressed as functions of the binary diffusion coefficients of each species pair in the mixture. Current models for the effective diffusion coefficients are incapable of providing a priori control over the error incurred in the approximate solution. In this paper a general form for diagonal approximations is derived, which accounts for the requirement imposed by the special structure of the Stefan-Maxwell equation that such approximations be constructed in a reduced-dimensional subspace. In addition, it is shown that current models can be expressed as particular cases of two general forms, but not all these models correspond to the general form for diagonal approximations. A new minimum error diagonal approximation (MEDA) model is proposed, based on the criterion that the diagonal approximation minimize the error in the species velocities. Analytic expressions are derived for the MEDA model's effective diffusion coefficients based on this criterion. These effective diffusion coefficients automatically give the correct solution in two important limiting cases: for that of a binary mixture, and for the case of arbitrary number of components with identical binary diffusivities, Although these minimum error effective diffusion coefficients are more expensive to compute than existing ones, the approximation will still be cheaper than computing the exact Stefan-Maxwell solution, while at the same time being more accurate than any other diagonal approximation, Furthermore, while the minimum error effective diffusion coefficients in this work are derived for bulk diffusion in homogeneous media, the minimization procedure can in principle be used to derive similar coefficients for diffusion problems in heterogeneous media which can be represented by similar forms of the Stefan-Maxwell equation. These problems include diffusion in macro- and microporous catalysts, adsorbents, and membranes. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Fluid Dynam Grp, Los Alamos, NM 87545 USA. RP Subramaniam, S (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Fluid Dynam Grp, T-3,M-S B216, Los Alamos, NM 87545 USA. NR 6 TC 7 Z9 7 U1 0 U2 1 PU WALTER DE GRUYTER & CO PI BERLIN PA GENTHINER STRASSE 13, D-10785 BERLIN, GERMANY SN 0340-0204 J9 J NON-EQUIL THERMODY JI J. Non-Equilib. Thermodyn. PY 1999 VL 24 IS 1 BP 1 EP 39 DI 10.1515/JNETDY.1999.001 PG 39 WC Thermodynamics; Mechanics SC Thermodynamics; Mechanics GA 209ZN UT WOS:000081080200001 ER PT J AU Butt, DP Park, Y Taylor, TN AF Butt, DP Park, Y Taylor, TN TI Thermal vaporization and deposition of gallium oxide in hydrogen SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article AB The thermodynamics of gallium oxide vaporization and deposition in Ar-6 H-2 at elevated temperatures are described. It is shown that Ga2O3 vaporizes in H-2 as Ga2O(g) at elevated temperatures. During thermal processing the Ga2O(g) moves to cooler zones of the furnace, back reacts with H-2(g) and H2O(g) and condenses out as Ga(1) and Ga2O3(s). Upon removal from the furnace, the exposed Ga forms a ubiquitous surface oxide of Ga2O3. X-ray photoelectron spectroscopy (XPS) was used to examine heat treated Ga2O3 powders and vaporization products deposited onto SiO2 and Cu substrates. In agreement with the thermodynamic predictions, these data demonstrate that the deposition product contained Ga2O3 and metallic Ga. Analysis of the XPS spectra also revealed an intermediate oxidation state for Ga. The precise bonding of this state could not be demonstrated conclusively, but it is suggested that it may be solid Ga2O. For coherent product deposition on Cu the metallic Ga concentration increases and the Ga2O3 concentration decreases with sputtering depth, suggesting the metallic Ga in the outermost layers of the deposit is readily oxidized during air exposure. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Butt, DP (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MST-6,POB 1663,MS G755, Los Alamos, NM 87545 USA. RI Butt, Darryl/B-7480-2008 OI Butt, Darryl/0000-0003-4501-8864 NR 17 TC 45 Z9 46 U1 1 U2 16 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 JAN 1 PY 1999 VL 264 IS 1-2 BP 71 EP 77 DI 10.1016/S0022-3115(98)00484-X PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 155CG UT WOS:000077927900008 ER PT J AU Carsughi, F Derz, H Ferguson, P Pott, G Sommer, W Ullmaier, H AF Carsughi, F Derz, H Ferguson, P Pott, G Sommer, W Ullmaier, H TI Investigations on Inconel 718 irradiated with 800 MeV protons SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article AB In spallation sources, the neutrons (utilized as probes for condensed matter research or for inducing nuclear transmutations) are generated by protons of around 1 GeV energy which cause spallation of the nuclei in a heavy metal target. The beam powers of the proposed future facilities are in the range of 1 to several 10 MW and the corresponding high particle fluxes make radiation damage the crucial effect for the lifetime of target structural materials in or close to the proton beam. In order to establish a database on spallation-relevant radiation effects, post-irradiation investigations of components of spent targets from operating medium power sources are being performed. Were we report first results on Inconel 718 irradiated in LAMPF up to a fluence of 3 x 10(25) p/m(2). Microhardness and bending tests together with SEM and TEM investigations show a considerable degradation of the mechanical properties of the material requiring additional highly controlled tests, now underway, to determine fracture toughness and tensile properties as a function of dose. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Forschungszentrum Julich, Inst Festkorperforsch, Julich, Germany. Forschungszentrum Julich, Heisse Zellen, Julich, Germany. Los Alamos Natl Lab, ATP Tech Project Off, Los Alamos, NM USA. Univ Ancona, Fac Agr, I-60131 Ancona, Italy. UdR Ancona, INFM, I-60131 Ancona, Italy. RP Carsughi, F (reprint author), Forschungszentrum Julich, Inst Festkorperforsch, Julich, Germany. OI Ferguson, Phillip/0000-0002-7661-4223 NR 25 TC 22 Z9 22 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 1999 VL 264 IS 1-2 BP 78 EP 88 DI 10.1016/S0022-3115(98)00475-9 PG 11 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 155CG UT WOS:000077927900009 ER PT J AU Zurek, AK AF Zurek, AK TI Preshock-induced phase transition in spalled U-0.75 wt% Ti SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID STRAIN AB Uranium-0.75 wt% Ti samples were spalled in the range of 5-24 GPa shock pressure. One sample was preshocked to a pressure of 24 GPa, 'soft' recovered, and then reloaded and spalled at 10 GPa. The spall strength of U-3/4 wt% Ti was found to range from -4.1 to -2.9 GPa when the Romanchenko correction is used in the spall strength calculation. The spall morphology of the sample that was preshocked and then spalled showed a significant change in microstructure from a parent alpha' martensite to a 2-phase eutectoid. The thermodynamically calculated temperature rise resulting from the preshock at 15-24 GPa in these samples is -555 degrees C. This temperature is not sufficient to induce such a phase change. However, the preshock conditions additionally increase the flow stress of the U-34 wt% Ti, and it is postulated that this additional hardening is sufficient to increase the temperature above 885 degrees C due to the increased amount of plastic work required during spall, thereby triggering the phase change. (C) 1999 Elsevier Science B.V. All rights re served. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Zurek, AK (reprint author), Univ Calif Los Alamos Natl Lab, MST-8 MS G755, Los Alamos, NM 87544 USA. NR 14 TC 2 Z9 3 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 1999 VL 264 IS 1-2 BP 155 EP 160 DI 10.1016/S0022-3115(98)00462-0 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 155CG UT WOS:000077927900016 ER PT J AU Chernikov, VN Wampler, WR Zakharov, AP Gorodetsky, AE AF Chernikov, VN Wampler, WR Zakharov, AP Gorodetsky, AE TI Deuterium trapping in deep traps of differently oriented pyrolytic graphite exposed to D-2 gas at 1473 K SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID NEUTRON-IRRADIATION; TRITIUM; CARBON; HYDROGEN; MICROSTRUCTURE; DIFFUSIVITY; SOLUBILITY; TRANSPORT; RETENTION; BEHAVIOR AB Due to their importance for tritium inventories in future DT fueled fusion machines, experimental data on H isotope diffusion, absorption and retention in deep traps (E-b congruent to 4.3 eV) of graphites exposed to hydrogen at elevated temperatures have been reviewed. Deuterium retention was studied in edge- and basal-oriented pyrolytic graphite (PG) and polycrystalline RG-Ti-91 damaged by irradiation with 200 keV carbon ions. Deuterium loading was done by soaking in D-2 gas at 1473 K, and the resulting D retention was measured by nuclear reaction analysis. The microstructure was studied by cross-sectional TEM, SEM and microprofilometry. The concentration of strong traps created by irradiation and estimated by the amount of accumulated deuterium was shown to saturate with the damage above approximate to 1 dpa at about 1000 appm. In non-damaged and damaged graphites deuterium diffuses via porous grain boundaries and along basal planes within crystallites, while its migration through the graphite lattice along the c direction was found to be negligible. Radiation modifications of PG retard deuterium diffusion and decrease the rate of its chemical erosion by a factor of five. The amount of deuterium accumulated in strong traps in graphites is mainly influenced by their macro- and microstructure, while the degree of graphitization seems to be less important. Derivations are made of the susceptibility of damaged graphites, in particular, CFCs to the retention of hydrogen isotopes in deep traps. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Russian Acad Sci, Inst Phys Chem, Moscow 117915, Russia. RP Wampler, WR (reprint author), Sandia Natl Labs, MS 1056, Albuquerque, NM 87185 USA. NR 50 TC 15 Z9 15 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 1999 VL 264 IS 1-2 BP 180 EP 197 DI 10.1016/S0022-3115(98)00466-8 PG 18 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 155CG UT WOS:000077927900019 ER PT J AU Hasegawa, A Saito, M Nogami, S Abe, K Jones, RH Takahashi, H AF Hasegawa, A Saito, M Nogami, S Abe, K Jones, RH Takahashi, H TI Helium-bubble formation behavior of SiCf/SiC composites after helium implantation SO JOURNAL OF NUCLEAR MATERIALS LA English DT Letter ID FIBERS; MICROSTRUCTURE; DIFFUSION; GRAPHITE AB Helium-bubble formation behavior in SiC-fiber-reinforced SiC-matrix (SiCf/SiC) composites was studied using helium implantation. Microstructural observation of the He-implanted specimens was carried out after post-implantation annealing at 1673 K for 1 h. Microstructural observation revealed small cavities in the SIC matrix only. No cavities were observed in the SiC fibers or in the carbon coating layers or their interfaces. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Tohoku Univ, Grad Sch Engn, Dept Quantum Sci & Energy Engn, Aoba Ku, Sendai, Miyagi 908579, Japan. Pacific NW Natl Lab, Richland, WA 99352 USA. Hokkaido Univ, CARET, Sapporo, Hokkaido 010, Japan. RP Hasegawa, A (reprint author), Tohoku Univ, Grad Sch Engn, Dept Quantum Sci & Energy Engn, Aoba Ku, Aramaki Aza Aoba 01, Sendai, Miyagi 908579, Japan. NR 15 TC 36 Z9 36 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN PY 1999 VL 264 IS 3 BP 355 EP 358 DI 10.1016/S0022-3115(98)00619-9 PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 156GM UT WOS:000077993300012 ER PT J AU Premuzic, ET Lin, MS AF Premuzic, ET Lin, MS TI Induced biochemical conversions of heavy crude oils SO JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING LA English DT Article DE biodegraded oils; bioconversion; selectivity; heavy oils; immature oils; microorganisms; biocatalysts; microbial; redistribution of hydrocarbon; mechanisms; upgrading of heavy crudes; heteroatoms ID ASPHALTENE AB Products formed during multiple interactions of microorganisms with oils fall into two major categories: those formed due to the action of indigenous microorganisms under reservoir conditions over geological periods of time and those products which are generated by the action of introduced organisms. The extreme end product of the first category is the production of heavy 'biodegraded' crudes. The extreme end product of the second category is the production of reduced sulfates due to the introduction of sulfate-reducing bacteria which may lead to the souring of a field. There is, however, a select group of microorganisms whose action on the crudes is beneficial. The interactions between such microorganisms and different crude oils occur through complex biochemical and chemical reactions. These reactions depend on multiple variables within and at the interface of a multicomponent system consisting of organic, aqueous, and inorganic components. Studies, carried out in this laboratory (BNL) of biochemical and chemical reactions in crude oils which involve extremophilic organisms (organisms which thrive in extreme environments), have shown that the reactions are not random and follow distinct trends. These trends can be categorized. The use of a group of characteristic chemical markers, such as mass spectrometric fragmentation patterns of light and heavy hydrocarbons, heterocyclic and organometallic compounds, as well as total trace metal and heteroatom contents of crude oils before and after the biochemical treatment allows to follow the type and the extent of chemical changes which occur during the biochemical conversion of heavy crude oils by microorganisms. The bioconversion involves multiple, simultaneous, and/or concurrent chemical reactions in which the microorganisms serve as biocatalysts. In this sense, the biocatalysts are active in a reaction medium which depends on the chemical composition of the crude and the selectivity of the biocatalyst. Thus, the bioconversion of the crude depends on the relative distribution of saturates, aromatics, resins, and asphaltenes and the distribution of polar compounds containing the heteroatoms(N, S, O) and trace metals. The role of these constituents in the bioconversion of crudes will be briefly reviewed in this paper. (C) 1999 Published by Elsevier Science B.V. Ail rights reserved. C1 Brookhaven Natl Lab, Dept Appl Sci, Biosyst & Proc Sci Div, Upton, NY 11973 USA. RP Premuzic, ET (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Biosyst & Proc Sci Div, Upton, NY 11973 USA. EM premuzic@bnl.gov NR 19 TC 23 Z9 27 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-4105 J9 J PETROL SCI ENG JI J. Pet. Sci. Eng. PD JAN PY 1999 VL 22 IS 1-3 BP 171 EP 180 DI 10.1016/S0920-4105(98)00066-7 PG 10 WC Energy & Fuels; Engineering, Petroleum SC Energy & Fuels; Engineering GA 167ZK UT WOS:000078665200017 ER PT J AU Lorenz, JC AF Lorenz, JC TI Stress-sensitive reservoirs SO JOURNAL OF PETROLEUM TECHNOLOGY LA English DT Article ID FRACTURE; BEHAVIOR; ROCK C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Lorenz, JC (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 12 TC 12 Z9 16 U1 0 U2 1 PU SOC PETROLEUM ENG PI RICHARDSON PA 222 PALISADES CREEK DR,, RICHARDSON, TX 75080 USA SN 0149-2136 J9 J PETROL TECHNOL JI J. Pet. Technol. PD JAN PY 1999 VL 51 IS 1 BP 61 EP 63 PG 3 WC Energy & Fuels; Engineering, Chemical; Engineering, Petroleum; Geosciences, Multidisciplinary SC Energy & Fuels; Engineering; Geology GA 201NH UT WOS:000080601300015 ER PT J AU Mauthe, RJ Sideras-Haddad, E Turtletaub, KW Bench, G AF Mauthe, RJ Sideras-Haddad, E Turtletaub, KW Bench, G TI Quantitative imaging microscopy for the sensitive detection of administered metal containing drugs in single cells and tissue slices - a demonstration using platinum based chemotherapeutic agents (vol 17, pg 651, 1998) SO JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS LA English DT Correction C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94500 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94500 USA. RP Bench, G (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94500 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0731-7085 J9 J PHARMACEUT BIOMED JI J. Pharm. Biomed. Anal. PD JAN PY 1999 VL 18 IS 6 BP 1069 EP 1069 PG 1 WC Chemistry, Analytical; Pharmacology & Pharmacy SC Chemistry; Pharmacology & Pharmacy GA 156HL UT WOS:000077995500018 ER PT J AU Volkow, ND Wang, GJ Fowler, JS Gatley, SJ Logan, J Ding, YS Dewey, SL Hitzemann, R Gifford, AN Pappas, NR AF Volkow, ND Wang, GJ Fowler, JS Gatley, SJ Logan, J Ding, YS Dewey, SL Hitzemann, R Gifford, AN Pappas, NR TI Blockade of striatal dopamine transporters by intravenous methylphenidate is not sufficient to induce self-reports of "high" SO JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS LA English DT Article ID DISCRIMINATIVE STIMULUS PROPERTIES; MEDIAL PREFRONTAL CORTEX; NUCLEUS-ACCUMBENS; COCAINE REINFORCEMENT; THREO-METHYLPHENIDATE; SQUIRREL-MONKEYS; BABOON BRAIN; RAT STRIATUM; BINDING; DRUGS AB The reinforcing effects of cocaine and methylphenidate have been linked to their ability to block dopamine transporters (DAT). Using positron emission tomography (PET), we previously showed that intravenous cocaine induced a significant level of DAT blockade, which was associated with the intensity for self-reports of "high" in cocaine abusers. In this study, we measured DAT occupancies after intravenous methylphenidate and assessed whether they also were associated with the "high". Occupation of DAT by intravenous MP was measured with PET using [C-11]cocaine; as a DAT ligand, in eight normal control subjects tested with different methylphenidate doses. The ratio of the distribution volume of [C-11]cocaine in striatum to that in cerebellum, which corresponds to B-max/Kd+1, was used as measure of DAT availability. In parallel, self-reports of "high" were measured. Methylphenidate produced a dose-dependent blockade of DAT with an estimated ED50 of 0.075 mg/kg. DAT occupancies were significantly correlated with the "high" (p <.03). However, four of the eight subjects, despite having significant levels of DAT blockade, did not perceive the "high". Methylphenidate is as effective as cocaine in blocking DAT in the human brain (cocaine ED50 = 0.13 mg/kg), and DAT blockade, as for cocaine, was also associated with the "high". However, the fact that there were subjects who despite significant DAT blockade did not experience the "high" suggests that DAT blockade, although necessary, is not sufficient to produce the "high". C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. RP Volkow, ND (reprint author), Brookhaven Natl Lab, Dept Med, Build 490, Upton, NY 11973 USA. FU NIDA NIH HHS [DA09490-01] NR 47 TC 81 Z9 82 U1 2 U2 2 PU AMER SOC PHARMACOLOGY EXPERIMENTAL THERAPEUTICS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0022-3565 J9 J PHARMACOL EXP THER JI J. Pharmacol. Exp. Ther. PD JAN PY 1999 VL 288 IS 1 BP 14 EP 20 PG 7 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 154CD UT WOS:000077870200003 PM 9862747 ER PT J AU Chekanov, SV AF Chekanov, SV TI Long-range correlations in deep-inelastic scattering SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article ID CHARGED-PARTICLE MULTIPLICITY; PP COLLISIONS; CM ENERGIES; DISTRIBUTIONS; ANNIHILATION; HADRONS; GEV/C AB Multiplicity correlations between the current and target regions of the Breit frame in deep-inelastic scattering processes are studied. It is shown that the correlations are sensitive to the first-order perturbative QCD effects and can be used to extract the behaviour of the boson-gluon fusion rates as a function of the Bjorken variable. The behaviour of the correlations is derived analytically and analyzed using a Monte Carlo simulation. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Chekanov, SV (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM chekanov@mail.desy.de NR 28 TC 7 Z9 7 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD JAN PY 1999 VL 25 IS 1 BP 59 EP 67 DI 10.1088/0954-3899/25/1/006 PG 9 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 164DB UT WOS:000078446200006 ER PT J AU Roy, M AF Roy, M TI Ultra high energy neutrinos from supernova remnants SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article ID GAMMA-RADIATION; CRAB-NEBULA; ACCELERATION; EMISSION AB In this paper we discuss possible ultra high energy (greater than or equal to TeV) neutrino emission from supernova remnants (SNRs), specifically the hadronic gamma-ray production models. Recent very high energy (VHE) gamma-ray observation from SNRs is the main motivation behind this study. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Roy, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,MS 50-245, Berkeley, CA 94720 USA. NR 25 TC 1 Z9 1 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD JAN PY 1999 VL 25 IS 1 BP 129 EP 134 DI 10.1088/0954-3899/25/1/011 PG 6 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 164DB UT WOS:000078446200011 ER PT J AU Sun, ZR Xia, XF Guo, Q Xu, D AF Sun, ZR Xia, XF Guo, Q Xu, D TI Protein structure prediction in a 210-type lattice model: Parameter optimization in the genetic algorithm using orthogonal array SO JOURNAL OF PROTEIN CHEMISTRY LA English DT Article DE protein folding; genetic algorithm; lattice model; optimization; orthogonal array ID FOLDING SIMULATIONS; CYTOCHROME-B562 AB We have applied the orthogonal array method to optimize the parameters in the genetic algorithm of the protein folding problem. Our study employed a 210-type lattice model to describe proteins, where the orientation of a residue relative to its neighboring residue is described by two angles. The statistical analysis and graphic representation show that the two angles characterize protein conformations effectively. Our energy function includes a repulsive energy, an energy for the secondary structure preference, and a pairwise contact potential. We used orthogonal array to optimize the parameters of the population, mating factor, mutation factor, and selection factor in the genetic algorithm. By designing an orthogonal set of trials with representative combinations of these parameters, we efficiently determined the optimal set of parameters through a hierarchical search. The optimal parameters were obtained from the protein crambin and applied to the structure prediction of cytochrome B562. The results indicate that the genetic algorithm with the optimal parameters reduces the computing time to reach a converged energy compared to nonoptimal parameters. It also has less chance to be trapped in a local energy minimum, and predicts a protein structure which is closer to the experimental one. Our method may also be applicable to many other optimization problems in computational biology. C1 Tsing Hua Univ, Dept Biol Sci & Biotechnol, State Key Lab Biomembrane & Membrane Engn, Beijing 100084, Peoples R China. NCI, Frederick Canc Res & Dev Ctr, IRSP, SAIC Frederick,Lab Expt & Computat Biol, Frederick, MD 21702 USA. RP Xu, D (reprint author), Oak Ridge Natl Lab, Computat Biosci Sect, POB 2008, Oak Ridge, TN 37830 USA. NR 19 TC 15 Z9 19 U1 0 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0277-8033 J9 J PROTEIN CHEM JI J. Protein Chem. PD JAN PY 1999 VL 18 IS 1 BP 39 EP 46 DI 10.1023/A:1020643331894 PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 169GZ UT WOS:000078740400005 PM 10071927 ER PT J AU Hoffman, DC AF Hoffman, DC TI Frontiers of heavy element nuclear and radiochemistry SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT Asia-Pacific Symposium on Radiochemistry 97 (APSORC 97) CY OCT 06-09, 1997 CL KUMAMOTO UNIV, KUMAMOTO, JAPAN HO KUMAMOTO UNIV ID GAUSSIAN-BASIS SET; ELECTRONIC-STRUCTURE; SUPERHEAVY ELEMENTS; TRANSACTINIDE ELEMENTS; CHEMISTRY; DECAY; IDENTIFICATION; APPARATUS; DISCOVERY; STABILITY AB The production and half-lives of the heaviest chemical elements, now known through Z = 112, are reviewed. Recent experimental evidence for the stabilization of heavy element isotopes due to proximity to deformed nuclear shells at Z = 108 and N = 162 is compared with the theoretical predictions. The possible existence of isotopes of elements 107-110 with half-lives of seconds or longer, and production reactions and experimental techniques for increasing the overall yields of such isotopes in order to study both their nuclear and chemical properties are discussed. The present status of studies of the chemical properties of Rf, Ha, and Sg is briefly summarized and prospects for extending chemical studies beyond Sg are considered. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94611 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Heavy Element Nucl & Radiochem Grp, Berkeley, CA 94611 USA. RP Hoffman, DC (reprint author), Univ Calif Berkeley, Dept Chem, MS-70A-3307, Berkeley, CA 94611 USA. EM Hoffman@lbl.gov NR 63 TC 2 Z9 2 U1 0 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0236-5731 EI 1588-2780 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JAN PY 1999 VL 239 IS 1 BP 7 EP 18 DI 10.1007/BF02349527 PG 12 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 160TY UT WOS:000078248200002 ER PT J AU Wunderlich, B Pyda, M AF Wunderlich, B Pyda, M TI Application of the Advanced Thermal Analysis System (ATHAS) to differential scanning calorimetry (DSC) and temperature-modulated DSC of polymers SO JOURNAL OF REINFORCED PLASTICS AND COMPOSITES LA English DT Article DE calorimetry; temperature-modulated calorimetry; heat capacity; transition ID GLASS-TRANSITION REGION; CELL ASYMMETRY; CRYSTALS AB The Advanced THermal Analysis System (ATHAS) involves the establishment of the link between heat capacity at low temperatures and molecular, vibrational motion. This description is then used to extrapolate the vibrational heat capacities to high temperatures. Next, the measured data can be analyzed in terms of conformational mobility, of importance to assess sample properties. Broad melting and glass transitions can thus be analyzed. Modem differential scanning calorimetry, DSC, and temperature-modulated DSC, TMDSC, are used to separate reversible and irreversible processes. An effort will be made to suggest when it is possible to apply quick DSC, and when it is necessary to use the slower, but more precise and informative TMDSC. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 28 TC 2 Z9 2 U1 0 U2 2 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 0731-6844 J9 J REINF PLAST COMP JI J. Reinf. Plast. Compos. PY 1999 VL 18 IS 6 BP 487 EP 498 PG 12 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA 205HX UT WOS:000080816200001 ER PT J AU Winokur, MJ Mattes, BR AF Winokur, MJ Mattes, BR TI Polyaniline as viewed from a structural perspective SO JOURNAL OF REINFORCED PLASTICS AND COMPOSITES LA English DT Article DE polyaniline; x-ray diffraction; structure and conducting polymer ID X-RAY-SCATTERING; CONDUCTING POLYMERS; TRANSPORT AB The local structural ordering of polyaniline (PANI) as emeraldine (i.e., at 50% oxidation) in both its base (EB) and salt (ES) forms has been studied using x-ray diffraction (XRD) techniques and these data reinforce the general belief that this local structure is extremely sensitive to the specific processing history. PANI powders precipitated as ES immediately following synthesis lead to reasonably crystalline materials whereas EB films cast from n-methyl pyrrolidine (NMP) solutions containing hydrogen bonding inhibitors are fully amorphous. Dedoping, by further treatments of ES with NH4OH solutions, or doping, by immersion of EB in aqueous HF solutions, lead to further changes in the local molecular structure. Many of these structural phases bear a limited, resemblance to the previously proposed structures for HCl-doped PANI powder and films [1,2]. The role of water hydration in the structural evolution is also examined and significant structural variations are found to occur in ES at radically different time scales. C1 Univ Wisconsin, Dept Civil Engn, Madison, WI 53706 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Winokur, MJ (reprint author), Univ Wisconsin, Dept Civil Engn, Madison, WI 53706 USA. NR 18 TC 5 Z9 5 U1 1 U2 5 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 0731-6844 J9 J REINF PLAST COMP JI J. Reinf. Plast. Compos. PY 1999 VL 18 IS 10 BP 875 EP 884 PG 10 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA 223LN UT WOS:000081842700001 ER PT J AU Kawaguchi, MN Denn, MM AF Kawaguchi, MN Denn, MM TI A mesoscopic theory of liquid crystalline polymers SO JOURNAL OF RHEOLOGY LA English DT Article ID GENERALIZED CONSTITUTIVE EQUATION; POLY(BENZYL GLUTAMATE) SOLUTIONS; MOLECULAR KINETIC-EQUATION; SHEAR FLOWS; RODLIKE POLYMERS; RHEOLOGICAL PROPERTIES; CONCENTRATED-SOLUTIONS; LESLIE COEFFICIENTS; DEFECT TEXTURE; DOI THEORY AB A kinetic equation for polydomains is used to develop a formal structure for a mesoscopic constitutive theory of textured liquid crystalline polymers. The lowest-order approximation for the texture terms leads to the Larson and Doi (1991) theory, but with a different meaning for the model parameters. Predicted macroscopic order parameters are in the range observed experimentally. (C) 1999 The Society of Rheology. [80148-6055(99)00301-6]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Kawaguchi, MN (reprint author), IBM Corp, Syst Storage Div, 5600 Cottle Rd, San Jose, CA 95193 USA. EM markkawa@us.ibm.com NR 63 TC 14 Z9 14 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0148-6055 J9 J RHEOL JI J. Rheol. PD JAN-FEB PY 1999 VL 43 IS 1 BP 111 EP 124 DI 10.1122/1.550979 PG 14 WC Mechanics SC Mechanics GA 155MQ UT WOS:000077951300008 ER PT J AU Hetrick, DM Pandey, A AF Hetrick, DM Pandey, A TI A methodology for establishing cleanup objectives in the unsaturated soil zone using sensitivity and uncertainty analysis for chemical fate and transport SO JOURNAL OF SOIL CONTAMINATION LA English DT Article DE sensitivity uncertainty analysis; SESOIL; soil leaching model AB To support the Corrective-Measures and Cleanup-Alternatives Studies (CMS) prepared by Science Applications international Corporation (SAIC) at the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio, a soil-leaching numerical analysis was conducted to help establish cleanup objectives for deep-soil contamination. For approximately 60 pollutants that exist at the PORTS site, the study defined those deep-soil concentrations that would most likely not cause groundwater contamination in excess of U.S. Environmental Protection Agency (USEPA) guidelines. These values were then used as the technical basis for defining soil-cleanup goals. Numerical modeling of environmental systems provides project managers with unique information that is not available from other sources. With its ability to quantify the important aspects of problem physics, modeling allows one to rapidly accumulate the physical insight needed to solve a problem in a systematic and focused manner. This increased understanding acquired early in the planning stages of a project permits managers to make decisions that are typically more thorough, cost effective, and defensible. This article describes one such numerical study conducted jointly by the Oak Ridge National Laboratory (ORNL) and SAIC for the PORTS. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Smalley & Associates Inc, Lancaster, OH 43130 USA. RP Hetrick, DM (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 13 TC 2 Z9 2 U1 0 U2 0 PU CRC PRESS INC PI BOCA RATON PA 2000 CORPORATE BLVD NW, JOURNALS CUSTOMER SERVICE, BOCA RATON, FL 33431 USA SN 1058-8337 J9 J SOIL CONTAM JI J. Soil Contam. PY 1999 VL 8 IS 5 BP 559 EP 576 PG 18 WC Environmental Sciences SC Environmental Sciences & Ecology GA 241VH UT WOS:000082904100003 ER PT J AU Ramlau, R McCarley, RE Simon, A AF Ramlau, R McCarley, RE Simon, A TI High-resolution electron microscopy investigations on the real structure of reduced barium oxomolybdates I. Polytypism and chemical intergrowth in Ba3Mo18O28 SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID SHARED MOLYBDENUM OCTAHEDRA; CLUSTERS; IN5MO18O28; NAMO4O6 AB Ba3Mo18O28, a reduced ternary molybdenum oxide in the series Mn+/-deltaMO4n+2O6n+4 with n = 4, is a cluster compound containing Mo4n+2O8n+10 clusters with n = 4 trans edge-sharing molybdenum octahedra. Crystals of the compound were investigated by high-resolution electron microscopy (HREM), selected-area electron diffraction (SAD), and electron probe microanalysis. Besides the known monoclinic 1M modification of Ba3Mo18O28 an orthorhombic 2O polytype was discovered, probably crystallizing in space group Pnam. Lattice parameters were estimated, and a rough structure model was generated, The real structure of Ba3Mo18O28 is characterized by: (i) intergrowth of both ordered polytypes, UM and 2O; (ii) stacking disorder; (iii) polysynthetic microtwinning of the VM polytype; (iv) disordered chemical intergrowth of Mo4n+2O8n+10-cluster layers with n = 2, 3, and 5; and (v) chemical intergrowth of the phase BaMo6O10 (formally n = 1). In connection with particular defects, an irregular condensation of clusters was observed, Discrepancies between experimental HREM and SAD results and related computer simulations are discussed, as well as the reliability of X-ray structure results from defective single crystals. (C) 1999 academic Press. C1 Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Ramlau, R (reprint author), Max Planck Inst Festkorperforsch, Heisenbergstr 1, D-70569 Stuttgart, Germany. NR 21 TC 2 Z9 2 U1 1 U2 3 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 JAN PY 1999 VL 142 IS 1 BP 89 EP 99 DI 10.1006/jssc.1998.7990 PG 11 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 162MG UT WOS:000078350200014 ER PT J AU Glass, DE Camarda, CJ Merrigan, MA Sena, JT AF Glass, DE Camarda, CJ Merrigan, MA Sena, JT TI Fabrication and testing of Mo-Re heat pipes embedded in carbon/carbon SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB Two heat-pipe test articles were fabricated and tested, furthering the development of a refractory-composite/heat-pipe-cooled leading edge. A 3-ft-long, molybdenum-rhenium heat pipe with lithium working fluid was fabricated and tested in a vacuum chamber at an operating temperature of 2460 degrees F, verifying the heat-pipe design, Following the fabrication of the initial heat pipe, three additional heat pipes were fabricated and embedded in carbon/carbon. The carbon/carbon heat pipe test article was successfully tested using quartz lamps in a vacuum chamber in both horizontal and vertical orientations. Startup and steady-state data indicated similar operation in both orientations but different behavior among the three heat pipes. Radiography and eddy current evaluations were performed on the test article and indicated differing carbon/carbon thicknesses and a potential disbond. C1 Analyt Serv & Mat Inc, Hampton, VA 23666 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Glass, DE (reprint author), Analyt Serv & Mat Inc, 107 Res Dr, Hampton, VA 23666 USA. NR 18 TC 8 Z9 11 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD JAN-FEB PY 1999 VL 36 IS 1 BP 79 EP 86 DI 10.2514/2.3436 PG 8 WC Engineering, Aerospace SC Engineering GA 166LJ UT WOS:000078577800008 ER PT J AU Bahat, D Grossenbacher, K Karasaki, K AF Bahat, D Grossenbacher, K Karasaki, K TI Mechanism of exfoliation joint formation in granitic rocks, Yosemite National Park SO JOURNAL OF STRUCTURAL GEOLOGY LA English DT Article ID SIERRA-NEVADA; PROPAGATION; CALIFORNIA; FRACTURE; PATHS AB Fractographic techniques reveal mechanical aspects of exfoliation in granitic rocks at Yosemite National Park, and electronic surveying provides information on their attitudes and dimensions. In the middle elevations of the cliff of El Capitan, exfoliation consists of early fractures a few meters to tens of meters in size which are fan-shaped. Fans at upper elevations point upwards, whereas fans at lower elevations point downwards parallel to the cliff. The fans interact with each other and merge into composite joints hundreds of meters in size, normal to the minimum compressive principal stress. This polarity indicates exfoliation by longitudinal splitting and buckling. The palaeostress causing the exfoliation on the southwestern side of Half Dome is estimated to range between 0.01 MPa and 0.94 MPa. Differences in fracture paleostresses of joints may be used in comparing their relative propagation velocities. It is suggested that the large exfoliation on the southwestern side of Half Dome had undergone a prolonged sub-critical growth before attaining rapid fracture velocities under post-critical conditions. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Ben Gurion Univ Negev, Dept Geol & Environm Sci, IL-84105 Beer Sheva, Israel. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Bahat, D (reprint author), Ben Gurion Univ Negev, Dept Geol & Environm Sci, IL-84105 Beer Sheva, Israel. NR 50 TC 35 Z9 38 U1 3 U2 14 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0191-8141 J9 J STRUCT GEOL JI J. Struct. Geol. PD JAN PY 1999 VL 21 IS 1 BP 85 EP 96 DI 10.1016/S0191-8141(98)00069-8 PG 12 WC Geosciences, Multidisciplinary SC Geology GA 157CW UT WOS:000078042900007 ER PT J AU Chapman, HN Vogt, S Jacobsen, C Kirz, J Miao, JW Wang, YX Winn, B Oversluizen, T AF Chapman, HN Vogt, S Jacobsen, C Kirz, J Miao, JW Wang, YX Winn, B Oversluizen, T TI A shutter-photodiode combination for UV and soft X-ray beamlines SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article DE shutter-photodiode combination AB A fast (similar to 12 ms) shutter for UHV beamlines is described. In the closed position the beam is blocked by an electrically isolated aluminium piece. The total yield photocurrent in this situation can be used to monitor the beam intensity. C1 SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Creat Instrumentat, E Patchogue, NY 11772 USA. RP Chapman, HN (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Chapman, Henry/G-2153-2010; Jacobsen, Chris/E-2827-2015; Winn, Barry/A-5065-2016; Vogt, Stefan/B-9547-2009; Vogt, Stefan/J-7937-2013 OI Chapman, Henry/0000-0002-4655-1743; Jacobsen, Chris/0000-0001-8562-0353; Winn, Barry/0000-0001-6383-4318; Vogt, Stefan/0000-0002-8034-5513; Vogt, Stefan/0000-0002-8034-5513 NR 2 TC 1 Z9 1 U1 1 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD JAN 1 PY 1999 VL 6 BP 50 EP 50 DI 10.1107/S0909049598013879 PN 1 PG 1 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 163YR UT WOS:000078435000007 ER PT J AU Taylor, PH Shanbhag, S Rubey, WA Dellinger, B Bergin, M AF Taylor, PH Shanbhag, S Rubey, WA Dellinger, B Bergin, M TI Speciation of organic by-products from the thermal decomposition of alternative automotive fuels SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID SPARK-IGNITION ENGINE; HYDROCARBON OXIDATION; EXHAUST PORT; REACTIVITY; PYROLYSIS AB The high-temperature thermal degradation of four alternative automotive fuels (methanol, ethanol, natural gas, and liquefied petroleum (LP) gas) have been examined as a function of fuel-oxygen equivalence ratio and exposure temperature using fused silica flow reactor instrumentation coupled to in-line GC-TCD and GC-MS detection. Organic speciation for methanol, natural gas, and LP gas were consistent with previous measurements. However, several previously undetected organic by-products were observed from ethanol oxidation and pyrolysis. Organic speciation was found to vary significantly between methanol and ethanol and less so between natural gas and LP gas. Non-methane organic gases (NMOG) and specific reactivities of the respective fuels were measured, and trends with respect to proposed reactivity adjustment factors are discussed. A qualitative comparison of NMOG quantified in the flow reactor tests with the results of recent vehicle tests is also reported. The most significant differences in the comparisons were observed for toxic compounds, including the lack of detection of acetaldehyde, 1,3-butadiene, and benzene from flow reactor experiments of methanol degradation, and the lack of detection of 1,3-butadiene from flow reactor experiments of ethanol combustion. Possible sources for the formation of these compounds in vehicle tests are discussed. C1 Univ Dayton, Res Inst, Environm Sci & Engn Grp, Mat Engn Div, Dayton, OH 45469 USA. Natl Renewable Energy Lab, Ctr Transportat Technol & Syst, Golden, CO USA. RP Taylor, PH (reprint author), Univ Dayton, Res Inst, Environm Sci & Engn Grp, Mat Engn Div, Dayton, OH 45469 USA. NR 18 TC 3 Z9 3 U1 1 U2 3 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA ONE GATEWAY CENTER, THIRD FL, PITTSBURGH, PA 15222 USA SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD JAN PY 1999 VL 49 IS 1 BP 39 EP 48 PG 10 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 153KF UT WOS:000077831700004 PM 28060610 ER PT J AU Singh, D Tlustochowicz, M Wagh, AS AF Singh, D Tlustochowicz, M Wagh, AS TI Development of zirconium magnesium phosphate composites for immobilization of fission products SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CERAMICS AB Novel chemically bonded phosphate ceramics have been investigated for the capture and stabilization of volatile fission-product radionuclides. We have used low-temperature processing to fabricate zirconium phosphate and zirconium/magnesium phosphate composites, A zirconium/magnesium phosphate composite has been developed and shown to stabilize ash waste that has been contaminated with a radioactive surrogate of the Cs-137 and Sr-90 species, Excellent retention of cesium in the phosphate matrix system was observed in both short- and long-term leaching tests, The retention factor determined by the USEPA Toxicity Characteristic Leaching Procedure was one order of magnitude better for cesium than for strontium, The effective diffusivity, at room temperature, for cesium and strontium in the waste forms was estimated to be as low as 2.4 x 10(-13) and 1.2 x 10(-11) cm(2)/s, respectively. This behavior was attributed to the capture of cesium in the layered zirconium phosphate structure via an intercalation ion-exchange reaction, followed by microencapsulation, However, strontium is believed to be precipitated out in its phosphate form and subsequently microencapsulated in the phosphate ceramic. The performance of these final waste forms, as indicated by the compression strength and the durability in aqueous environments, satisfies the regulatory criteria. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Singh, D (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Wagh, Arun/0000-0002-8678-7574 NR 25 TC 5 Z9 5 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JAN PY 1999 VL 82 IS 1 BP 43 EP 49 PG 7 WC Materials Science, Ceramics SC Materials Science GA 158UC UT WOS:000078134500006 ER PT J AU Schilling, CH Bellman, RA Smith, RM Goel, H Giesche, H AF Schilling, CH Bellman, RA Smith, RM Goel, H Giesche, H TI Plasticizing aqueous suspensions of concentrated alumina with maltodextrin sugar SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID PARTICLE PACKING; HYDRATION FORCES; SLURRIES; PRESSURE; CONSOLIDATION; POTENTIALS; BEHAVIOR; RHEOLOGY; AL2O3; ACID AB Aqueous suspensions of submicrometer, 20 vol% Al2O3 powder exhibited a transition from strongly flocculated, thixotropic behavior to a low-viscosity, Newtonian-libe state upon adding small amounts of maltodextrin (0.03 g of maltodextrin/(g of Al2O3)), These suspensions could be filter pressed to highly dense (57%) and extrudable pastes only when prepared with maltodextrin, We analyzed the interaction of maltodextrin with Al2O3 powder surfaces and quantitatively measured the resulting claylike consolidation, rheological, and extrusion behaviors. Benbow extrusion parameters were comparable to, but higher than, those of kaolin at approximately the same packing density of 57 vol%. In contrast, Al2O3 filter cakes without maltodextrin at 57 vol% density were too stiff to be extruded, Measurements of rheological properties, acoustophoresis, electrophoresis, sorption isotherms, and diffuse reflectance Fourier infrared spectroscopy supported the hypothesis that sorbate-mediated steric hindrance, rather than electrostatic, interparticle repulsion, is important to enhancing the consolidation and fluidity of maltodextrin-Al2O3 suspensions. Viscosity measurements on aqueous maltodextrin solutions indicated that free maltodextrin in solution does not improve suspension fluidity by decreasing the viscosity of the interparticle solution. C1 Iowa State Univ, Ames Lab, Ames, IA 50010 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50010 USA. Alfred Univ, New York State Coll Ceram, Alfred, NY 14802 USA. RP Schilling, CH (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50010 USA. NR 50 TC 26 Z9 26 U1 2 U2 8 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JAN PY 1999 VL 82 IS 1 BP 57 EP 66 PG 10 WC Materials Science, Ceramics SC Materials Science GA 158UC UT WOS:000078134500008 ER PT J AU Mann, AB Balooch, M Kinney, JH Weihs, TP AF Mann, AB Balooch, M Kinney, JH Weihs, TP TI Radial variations in modulus and hardness in SCS-6 silicon carbide fibers SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID MICROSTRUCTURE AB The mechanical properties of SCS-6 SiC fibers were measured as a function of fiber radius using nanoindentation techniques. Hardness and Young's modulus were characterized for the material in all of the major regions of these fibers: the carbon core, the graphitic core coating, the inner SiC sheath, and the outer SiC sheath. The carbon core of the fibers was determined to be uniform in properties but extremely compliant, Young's modulus of 28 GPa and a hardness of 4.2 GPa were measured. The graphitic core coating was found to exhibit considerable anelasticity and to have both a low modulus (21 GPa) and a low hardness (1.7 GPa), The inner sheath of the fiber, which contained a varying chemistry, showed a sharp increase in stiffness and hardness from the inner core. Modulus and hardness increased by an order of magnitude over just 1 or 2 mu m when transversing radially away from the core into the SiC. This change in properties was pronounced and clearly defined. The outer sheath, which contained a uniform chemistry and microstructure, nas consistently stiff and hard when transversing radially. The average modulus and hardness for the full fiber was 333 GPa, The values reported for Young's modulus and hardness clearly showed that the mechanical properties of SCS SiC fibers exhibit dramatic changes across their diameters. C1 Johns Hopkins Univ, Dept Mat Sci & Engn, Baltimore, MD 21218 USA. Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94551 USA. RP Mann, AB (reprint author), Johns Hopkins Univ, Dept Mat Sci & Engn, Baltimore, MD 21218 USA. RI Mann, Adrian/A-3992-2012; Weihs, Timothy/A-3313-2010 NR 20 TC 8 Z9 8 U1 0 U2 5 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JAN PY 1999 VL 82 IS 1 BP 111 EP 116 PG 6 WC Materials Science, Ceramics SC Materials Science GA 158UC UT WOS:000078134500015 ER PT J AU Ackler, HD Chiang, YM AF Ackler, HD Chiang, YM TI Effect of initial microstructure on final intergranular phase distribution in liquid-phase-sintered ceramics SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID EQUILIBRIUM THICKNESS; HAMAKER CONSTANTS; SILICON-NITRIDE; GLASS; PARTICLES; SYSTEMS; SI3N4; FILM AB The glass-melt penetration of dense TiO2 polycrystals (where the grains are initially in contact) and the sintering of SiO2-coated TiO2 powders (where the grains are initially separated) have been used to investigate the influence of initial particle separation on final microstructures. Grains that were initially in sintered contact resisted penetration by the liquid and retained crystalline boundaries. However, grains that were initially separated by liquid had a tendency to form a final state where they were separated by a glass film similar to 1 nm thick. The results imply that crystalline grain boundaries and those that contain a thin amorphous film represent two local thermodynamic minima that are separated by an energy barrier. These observations are in agreement with a thermodynamic model that predicted such a barrier for this system, and these observations show that the stable phase distribution in liquid-phase-sintered ceramics can be dependent on the path. C1 MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA. RP Ackler, HD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Microtechnol Ctr, Livermore, CA 94551 USA. NR 22 TC 22 Z9 22 U1 0 U2 3 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JAN PY 1999 VL 82 IS 1 BP 183 EP 189 PG 7 WC Materials Science, Ceramics SC Materials Science GA 158UC UT WOS:000078134500024 ER PT J AU Gorshkov, MV Pasa-Tolic, L Smith, RD AF Gorshkov, MV Pasa-Tolic, L Smith, RD TI Pressure limited sustained off-resonance irradiation for collision-activated dissociation in Fourier transform mass spectrometry SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID LINE SHAPES; ABSORPTION; EXCITATION; IONS AB A theoretical evaluation of the sustained off-resonance irradiation of ions (SORI) in the presence of a collisional buffer gas in a Fourier transform ion cyclotron resonance mass spectrometer is presented. It is shown that there is an optimal pressure for a given set of irradiation parameters corresponding to the most effective dissociation. Theoretical predictions are compared with experimental results for the dissociation of electrosprayed biopolymer ions and with previously accepted view of the SORT process. (J Am Soc Mass Spectrom 1999, 10, 15-18) (C) 1999 American Society for Mass Spectrometry. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. RI Gorshkov, Mikhail/E-8522-2010; Smith, Richard/J-3664-2012; Gorshkov, Mikhail/N-4984-2013 OI Smith, Richard/0000-0002-2381-2349; Gorshkov, Mikhail/0000-0001-9572-3452 FU NIGMS NIH HHS [GM 53558] NR 16 TC 10 Z9 10 U1 0 U2 0 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 JAN PY 1999 VL 10 IS 1 BP 15 EP 18 DI 10.1016/S1044-0305(98)00119-6 PG 4 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 149CC UT WOS:000077586700004 PM 9888181 ER PT J AU Thompson, DW Schoonover, JR Meyer, TJ Argazzi, R Bignozzi, CA AF Thompson, DW Schoonover, JR Meyer, TJ Argazzi, R Bignozzi, CA TI Excited state electronic properties of the [(phen)(OC)(3)Re-I(NC)Ru-II(bpy)(2)(CN)]PF6 and [(phen)(OC)(3)Re-I(CN)Ru-II(bpy)(2)(CN)]PF6 linkage isomers SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID INTRAMOLECULAR ENERGY-TRANSFER; RESOLVED VIBRATIONAL SPECTROSCOPY; POLYPYRIDINE COMPLEXES; RUTHENIUM(II) COMPLEXES; LUMINESCENCE; ASSEMBLIES; GAP AB The results of temperature dependent emission lifetimes, emission spectral fitting and excited state transient absorption spectroscopy of the two hetero-dinuclear [(phen)(OC)(3)Re-I(CN)Ru-II(bpy)(2)(CN)](+) and [(phen)(OC)(3)Re-I(NC)Ru-II(bpy)(2)(CN)](+) linkage isomers (abbreviated Re-CN-Ru and Re-NC-Ru) have been examined. In both dinuclear species efficient intramolecular Re*--> Ru energy transfer occurs, leading to population of emitting d(pi)(Ru)-pi*(bpy), (MLCT)-M-3 states. The temperature dependent emission data suggest that the barrier for the MLCT-dd surface crossing is smaller in magnitude when the "[(phen)(OC)(3)Re(NC)]" moiety is bound to the Ru(bpy)(2)(CN) emitting unit. This is interpreted as the result of its enhanced ability to backbond from Ru-II which increases the energy of the MLCT relative to the dd states. C1 Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA. Univ Calif Los Alamos Natl Lab, Dept Chem, Los Alamos, NM 87545 USA. Univ Ferrara, CNR, Ctr Studio Fotoreatt & Catalisi, Dipartimento Chim, I-44100 Ferrara, Italy. RP Thompson, DW (reprint author), Univ N Carolina, Dept Chem, CB 3290, Chapel Hill, NC 27599 USA. RI Argazzi, Roberto/C-4819-2015; OI Argazzi, Roberto/0000-0002-2619-6860; Bignozzi, Carlo Alberto/0000-0002-7882-3694 NR 32 TC 11 Z9 11 U1 0 U2 4 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0300-9246 J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PY 1999 IS 21 BP 3729 EP 3734 DI 10.1039/a905783h PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 249ML UT WOS:000083336800011 ER PT J AU Antonio, MR Soderholm, L Williams, CW Ullah, N Francesconi, LC AF Antonio, MR Soderholm, L Williams, CW Ullah, N Francesconi, LC TI Redox behavior of cerium in heteropolyoxotungstate complexes SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID X-RAY-ABSORPTION; NEAR-EDGE STRUCTURE; OXIDATION-STATE; FINE-STRUCTURE; HETEROPOLYANION (12-); LANTHANIDE COMPLEXES; COORDINATION; VALENCE; SPECTROSCOPY; CE AB In situ XAFS spectroelectrochemistry is used to characterize the oxidation state and coordination environment of cerium in two different heteropolytungstates, the Wells-Dawson [Ce(alpha-2-P2W17O61)(2)](17-) anion, and the Preyssler [CeP5W30O110](12-) anion. Ce(III), coordinated to the Wells-Dawson framework, is oxidized at an applied potential of +0.37 V vs. Ag/AgCl. This is 1.15 V less than the Ce(IV)/Ce(III) standard reduction potential of +1.52 V vs. Ag/AgCl, demonstrating that Ce(IV) is stabilized in this heteropolyanion. In contrast, Ce(III) when encapsulated in the Preyssler anion is not oxidized at potentials higher than would be required for its oxidation in a non-complexing medium, indicating a stabilization of Ce(III). This is despite the 12- charge on the anion. The different redox behavior of Ce is understood in terms of the different coordination environments afforded by the two heteropolyanions. The relative importance of saturative coordination versus electrostatic stabilization in the redox behavior of these two complexes is discussed. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. CUNY Hunter Coll, Dept Chem, New York, NY 10021 USA. RP Antonio, MR (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Antonio, Mark/0000-0002-1208-4534 NR 68 TC 26 Z9 26 U1 3 U2 13 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0300-9246 J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PY 1999 IS 21 BP 3825 EP 3830 DI 10.1039/a904071d PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 249ML UT WOS:000083336800024 ER PT J AU Liu, CT Wu, JK AF Liu, CT Wu, JK TI A Special Issue on Materials Science and Engineering - Guest Editors' foreword SO JOURNAL OF THE CHINESE INSTITUTE OF ENGINEERS LA English DT Editorial Material C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Natl Taiwan Ocean Univ, Keelung, Taiwan. RP Liu, CT (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU CHINESE INST ENGINEERS PI TAIPEI PA #1, 4TH FL, SEC 2, JEN-AI RD, TAIPEI 10019, TAIWAN SN 0253-3839 J9 J CHIN INST ENG JI J. Chin. Inst. Eng. PD JAN PY 1999 VL 22 IS 1 BP I EP I PG 1 WC Engineering, Multidisciplinary SC Engineering GA 161BK UT WOS:000078267900001 ER PT J AU Schneibel, JH Becher, PF AF Schneibel, JH Becher, PF TI Iron and nickel aluminide composites SO JOURNAL OF THE CHINESE INSTITUTE OF ENGINEERS LA English DT Article DE composite; intermetallics; iron aluminides; nickel aluminides; mechanical properties ID CERAMIC COMPOSITES; FRACTURE-BEHAVIOR; MELT-INFILTRATION; STRENGTH; PHASE AB Iron and nickel aluminide intermetallics are not only oxidation and corrosion resistant, but also thermodynamically compatible with a wide range of ceramics. This makes them suitable as the matrix for a wide range of composite systems. Among the composites evaluated to date are combinations of FeAl or Ni3Al with WC, TiC, SiC, TiB2, and Al2O3, With ceramic volume fractions ranging from (5 to 90%. A variety of processing techniques has been employed, but conventional liquid phase sintering and pressureless melt infiltration appear to be the most successful ones. Recently, a novel one-step melt infiltration procedure has been developed to fabricate composites with ceramic volume fractions approaching 90%. Room temperature flexure strengths as high as 1.8 GPa have been obtained. Both FeAl and Ni3Al composites exhibit fracture toughnesses similar to those of WC/Co. It is found that sufficiently thin (< 2 mu m) ligaments of FeAl tend to fracture in a ductile manner. The absence of cleavage fracture in these thin ligaments is due to the unavailability of sufficiently long dislocation pile-ups for nucleating cleavage cracks. In addition to the mechanical properties of FeAl and Ni3Al composites, other properties of interest such as wear and corrosion resistance are briefly discussed. The properties of FeAl and Ni3Al composites are seen to complement each other and may be of interest in those applications where WC/Co composites have limitations. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Schneibel, JH (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 44 TC 21 Z9 21 U1 2 U2 5 PU CHINESE INST ENGINEERS PI TAIPEI PA #1, 4TH FL, SEC 2, JEN-AI RD, TAIPEI 10019, TAIWAN SN 0253-3839 EI 2158-7299 J9 J CHIN INST ENG JI J. Chin. Inst. Eng. PD JAN PY 1999 VL 22 IS 1 BP 1 EP 12 DI 10.1080/02533839.1999.9670437 PG 12 WC Engineering, Multidisciplinary SC Engineering GA 161BK UT WOS:000078267900002 ER PT J AU Vogt, T Reilly, JJ Johnson, JR Adzic, GD McBreen, J AF Vogt, T Reilly, JJ Johnson, JR Adzic, GD McBreen, J TI Site preference of cobalt and deuterium in the structure of a complex AB(5) alloy electrode - A neutron powder diffraction study SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID HYDROGEN AB The site preference of cobalt and deuterium in the charged and discharged state of a commercial-type metal hydride anode was investigated by high resolution neutron powder diffraction using an alloy with an altered isotope composition. in the alloy La(Ni-58(0.376) Ni-62(0.624))(3.55)Co0.75Mn0.33Al0.30 the isotope ratio of Ni-58 to Ni-62 leads to a zero neutron scattering length for nickel. Rietveld refinement revealed that Al and Mn occupy the midplane 3g sites of the CaCu5 structure, while cobalt has a preference for 3g but also occupies the basal plane 2c sites. The space group of the deuteride remains P6/mmm which differs from the parent LaNi5D7 which is P6(3)mc. (C) 1999 The Electrochemical Society. S0013-4651(98)03-104-8. All rights reserved. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Vogt, T (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Vogt, Thomas /A-1562-2011 OI Vogt, Thomas /0000-0002-4731-2787 NR 16 TC 24 Z9 25 U1 0 U2 0 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 JAN PY 1999 VL 146 IS 1 BP 15 EP 19 DI 10.1149/1.1391557 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 157GZ UT WOS:000078054400003 ER PT J AU Ryan, MP Laycock, NJ Isaacs, HS Newman, RC AF Ryan, MP Laycock, NJ Isaacs, HS Newman, RC TI Corrosion pits in thin films of stainless steel SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID PITTING CORROSION; LOCALIZED CORROSION; SULFIDE INCLUSIONS; ANODIC-DISSOLUTION; MECHANISM; ALUMINUM; INITIATION; STABILITY; ALLOYS; GROWTH AB Thin stainless steel films were prepared by sputter deposition onto silicon substrates using a 304 stainless steel target. The film composition was essentially that of 304 stainless steel, but they had a body-centered cubic structure and were free of sulfide inclusions. Potentiodynamic polarization curves were obtained for thin films in various chloride-containing solutions and compared to results from conventional stainless steel samples. In addition, video images of two-dimensional pits in thin films were used to determine the anodic pit current density as functions of potential and chloride concentration. Thin stainless steel films were found to be significantly more resistant to pit initiation than their bulk counterparts, but pit propagation was possible at relatively low potentials. A diffusion-controlled growth regime was identified at high potentials, with a transition to mixed activation/ohmic control at lower potentials (just above that required for repassivation). (C) 1999 The Electrochemical Society. S0013-4651(98)04-038-5. All rights reserved. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Mat Performance Technol, Lower Hutt, New Zealand. Univ Manchester, Inst Sci & Technol, Ctr Corros & Protect, Manchester M60 1QD, Lancs, England. RP Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RI Street, Steven/A-5398-2015; OI Street, Steven/0000-0002-8999-3701; Ryan, Mary/0000-0001-8582-3003 NR 41 TC 29 Z9 31 U1 2 U2 20 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 JAN PY 1999 VL 146 IS 1 BP 91 EP 97 DI 10.1149/1.1391569 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 157GZ UT WOS:000078054400015 ER PT J AU Ramasubramanian, M Popov, BN White, RE Chen, KS AF Ramasubramanian, M Popov, BN White, RE Chen, KS TI A mathematical model for electroless copper deposition on planar substrates SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID MECHANISMS; KINETICS AB A mathematical model for the electroless deposition of copper on a planar electrode is presented and used to make time-dependent predictions on the various quantities in the system. The model takes into account mass transport by diffusion and migration, Butler-Volmer kinetics at the electrode surface, and mixed potential theory. A finite difference approach is used to solve the equations, and the resultant model is used to predict the concentration profiles, potential response, and plating rate as a function of time and concentration of various reactive components. (C) 1999 The Electrochemical Society. S0013-4651(98)02-031-X. All rights reserved. C1 Univ S Carolina, Dept Chem Engn, Ctr Electrochem Engn, Columbia, SC 29208 USA. Sandia Natl Labs, Engn Sci Ctr, Albuquerque, NM 87185 USA. RP Ramasubramanian, M (reprint author), Univ S Carolina, Dept Chem Engn, Ctr Electrochem Engn, Columbia, SC 29208 USA. NR 18 TC 14 Z9 14 U1 1 U2 7 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 JAN PY 1999 VL 146 IS 1 BP 111 EP 116 DI 10.1149/1.1391572 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 157GZ UT WOS:000078054400018 ER PT J AU Stein, DJ Hetherington, DL Cecchi, JL AF Stein, DJ Hetherington, DL Cecchi, JL TI Investigation of the kinetics of tungsten chemical mechanical polishing in potassium iodate-based slurries - I. Role of alumina and potassium iodate SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ATOMIC-SCALE; FRICTION AB We investigated aspects of the kinetics of tungsten chemical mechanical polishing (CMP) in iodate-based slurries. Specifically, we performed experiments in which we measured the tungsten polish rate and process temperature as a function of alumina concentration, potassium iodate concentration, platen temperature, polish pressure, polish rotation rate, and pad type. We found that the polish rate data fit a multiterm regression model better than the empirical Preston equation. Polish rate was found to vary with all of me factors investigated. Process temperature varied with all of the factors except potassium iodate concentration. These results, in combination with an energy balance on the entire process, indicate the change in temperature due to alumina concentration is mostly due to energy input from increased shaft work. This implies that the chemical and physical interactions between the alumina and tungsten surfaces are complex and play an important role in the mechanism of tungsten removal during CMP. (C) 1999 The Electrochemical Society. S0013-4651(98)04-096-8. All rights reserved. C1 Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87131 USA. Sandia Natl Labs, Microelect Dev Lab, Albuquerque, NM 87185 USA. RP Stein, DJ (reprint author), Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87131 USA. NR 19 TC 44 Z9 48 U1 1 U2 5 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JAN PY 1999 VL 146 IS 1 BP 376 EP 381 DI 10.1149/1.1391617 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 157GZ UT WOS:000078054400063 ER PT J AU Wereszczak, AA Ferber, MK Kirkland, TP Barnes, AS Frome, EL Menon, MN AF Wereszczak, AA Ferber, MK Kirkland, TP Barnes, AS Frome, EL Menon, MN TI Asymmetric tensile and compressive creep deformation of hot-isostatically-pressed Y2O3-doped-Si3N4 SO JOURNAL OF THE EUROPEAN CERAMIC SOCIETY LA English DT Article DE Si3N4; creep; electron microscopy; mechanical properties; modelling ID SILICON-NITRIDE CERAMICS; STRESS RUPTURE BEHAVIOR; PERFORMANCE; GLASS AB The uniaxial tensile and compressive creep rates of an yttria-containing hot-isostatically-pressed silicon nitride were examined at several temperatures between 1316 and 1399 degrees C and found to have different stress dependencies. Minimum creep rates were always faster in tension than compression for an equal magnitude of stress. An empirical model was formulated which represented the minimum creep rate as a function of temperature for both tensile and compressive stresses. The model also depicted the asymmetric creep deformation using exponential and linear dependence on tensile and compressive stress, respectively. Unlike other models which represent either tensile or compressive creep deformation as a respective function of tensile or compressive stress, the model in the present study predicted creep deformation rate for both tensile and compressive stresses without conditional or a priori knowledge of the sign of stress. A statistical weight function was introduced to improve the correlation of the model's regressed fit to the experimental data. Post-testing TEM microstructural analysis revealed that differences in the amount of tensile- and compressive-stress-induced cavitation accounted for the creep strain asymmetry between them, and that cavitation initiated in tensile and compressively crept specimens for magnitudes of creep strain in excess of 0.1%. (C) 1998 Elsevier Science Limited. All rights reserved. C1 Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. Allied Signal Aerosp Co, Allied Signal Engines, Phoenix, AZ 85072 USA. RP Wereszczak, AA (reprint author), Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RI Wereszczak, Andrew/I-7310-2016 OI Wereszczak, Andrew/0000-0002-8344-092X NR 34 TC 38 Z9 38 U1 0 U2 3 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. PY 1999 VL 19 IS 2 BP 227 EP 237 DI 10.1016/S0955-2219(98)00184-8 PG 11 WC Materials Science, Ceramics SC Materials Science GA 154DZ UT WOS:000077874500010 ER PT J AU Kitayama, M Powers, JD Kulinsky, L Glaeser, AM AF Kitayama, M Powers, JD Kulinsky, L Glaeser, AM TI Surface and interface properties of alumina via model studies of microdesigned interfaces SO JOURNAL OF THE EUROPEAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT Meeting on New Developments in High Temperature Materials CY AUG 12-15, 1998 CL ISTANBUL, TURKEY DE surface diffusion; surface energy; interfaces; porosity; Al2O3 ID ION-IMPLANTED SAPPHIRE; CRACK-LIKE FLAWS; MORPHOLOGICAL EVOLUTION; VICINAL SURFACES; FREE-ENERGY; DIFFUSION; PROFILES; SPHEROIDIZATION; SEGREGATION; ANISOTROPY AB The ability to produce controlled-geometry, controlled-crystallography internal voids in ceramics has made possible several new model experiments for studying the high-temperature properties of surfaces and interfaces in ceramics. Recent advances have enabled the production of more complex microdesigned internal defect structures, and have exploited new means of examining them, thus, broadening the range of problems that can be addressed. A particular topic of concern is the effect of surface energy anisotropy on both the driving force for and the mechanism of shape changes. This paper reviews and previews recent research focussing on improving our understanding of surface diffusion in ceramics. Rayleigh instabilities provide one means of examining morphological evolution. The modelling of Rayleigh instabilities in materials with surface energy anisotropy is reviewed, and the results of experiments utilizing microdesigned pore arrays in sapphire are summarized. In a material with anisotropic surface energy and a facetted Wulff shape, the driving force for shape changes hinges on both the absolute and relative surface energies. Microdesigned pore structures have been used to determine the stable surfaces in both undoped and doped sapphire and to provide the relative values of the energies of these stable surfaces; Nonequilibrium shape, controlled-crystallography cavities have been introduced into undoped sapphire, and the effect of crystallographic orientation on their morphological evolution has been studied. Comparisons of the results with predictions of models of surface-diffusion-controlled evolution indicate that surface-attachment-limited kinetics (SALK) play an important role. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. RP Glaeser, AM (reprint author), Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, 787 Evans Hall,MC 1760, Berkeley, CA 94720 USA. NR 73 TC 24 Z9 24 U1 4 U2 13 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. PY 1999 VL 19 IS 13-14 BP 2191 EP 2209 DI 10.1016/S0955-2219(99)00102-8 PG 19 WC Materials Science, Ceramics SC Materials Science GA 243PE UT WOS:000083005800002 ER PT J AU Pennycook, SJ Dickey, EC Nellist, PD Chisholm, MF Yan, Y Pantelides, ST AF Pennycook, SJ Dickey, EC Nellist, PD Chisholm, MF Yan, Y Pantelides, ST TI A combined experimental and theoretical approach to atomic structure and segregation at ceramic interfaces SO JOURNAL OF THE EUROPEAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT Meeting on New Developments in High Temperature Materials CY AUG 12-15, 1998 CL ISTANBUL, TURKEY DE interfaces; simulation; electron microscopy; Z-contrast imaging; grain boundaries ID TRANSMISSION ELECTRON-MICROSCOPE; GRAIN-BOUNDARY; MGO AB In the last few years, the scanning transmission electron microscope has become capable of forming electron probes of atomic dimensions. This makes possible the technique of Z-contrast imaging, a method of forming direct images at atomic resolution with high compositional sensitivity. Atomic column positions can be determined to high accuracy from the image, and columns containing high-Z impurities will be visible. Atomic resolution electron energy loss spectroscopy is possible by locating the probe over particular atomic columns or planes seen in the image. This provides complementary information on low-Z species and chemical bonding. Such data represents an ideal starting point for first-principles theoretical calculations of energetics and dynamics, avoiding time-consuming searches of trial structures. Examples are shown of ordering in relaxer ferroelectrics, interfacial termination in oxide-oxide and metal-oxide interfaces, and an impurity-induced structural transformation of a ceramic grain boundary. Published by Elsevier Science Ltd. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Kentucky, Dept Chem & Mat Engn, Lexington, KY 40506 USA. Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RP Pennycook, SJ (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Dickey, Elizabeth/A-3368-2011 OI Dickey, Elizabeth/0000-0003-4005-7872 NR 16 TC 5 Z9 5 U1 1 U2 7 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. PY 1999 VL 19 IS 13-14 BP 2211 EP 2216 DI 10.1016/S0955-2219(99)00126-0 PG 6 WC Materials Science, Ceramics SC Materials Science GA 243PE UT WOS:000083005800003 ER PT J AU Loong, CK AF Loong, CK TI Phonon densities of states and related thermodynamic properties of high temperature ceramics SO JOURNAL OF THE EUROPEAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT Meeting on New Developments in High Temperature Materials CY AUG 12-15, 1998 CL ISTANBUL, TURKEY DE neutron scattering; Si3N4; AlN; GaN; sialon; modelling; thermodynamic properties ID SILICON-NITRIDE; OF-STATES; THERMAL-PROPERTIES; CRYSTAL-STRUCTURE; LATTICE-DYNAMICS; VITREOUS SILICA; GALLIUM NITRIDE; MORPHOLOGY; BEHAVIOR; NEUTRON AB Structural components and semiconductor devices based on silicon nitride, aluminum nitride and gallium nitride are expected to function more reliably at elevated temperatures and at higher levels of performance because of the strong atomic bonding in these materials. The degree of covalency, lattice specific heat, and thermal conductivity are important design factors for the realization of advanced applications. We have determined the phonon densities of states of these ceramics by the method of neutron scattering. The results provide a microscopic interpretation of the mechanical and thermal properties. Moreover, experimental data of the static structures and dynamic excitations of atoms are essential to the validation of interparticle potentials employed for molecular-dynamics simulations of high-temperature properties of multi-component ceramic systems. We present an overview of neutron-scattering investigations of the atomic organization, phonon excitations, as well as calculations of related thermodynamic properties of Si3N4, beta-sialon, AlN and GaN. The results ave compared with those of the oxide analogs such as SiO2 and Al2O3. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. EM ckloong@anl.gov NR 31 TC 16 Z9 16 U1 1 U2 11 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0955-2219 EI 1873-619X J9 J EUR CERAM SOC JI J. Eur. Ceram. Soc. PY 1999 VL 19 IS 13-14 BP 2241 EP 2247 DI 10.1016/S0955-2219(99)00110-7 PG 7 WC Materials Science, Ceramics SC Materials Science GA 243PE UT WOS:000083005800006 ER PT J AU Chatterjee, A Campbell, T Kalia, RK Nakano, A Omeltchenko, A Tsuruta, K Vashishta, P Ogata, S AF Chatterjee, A Campbell, T Kalia, RK Nakano, A Omeltchenko, A Tsuruta, K Vashishta, P Ogata, S TI Parallel molecular dynamics simulations of high temperature ceramics SO JOURNAL OF THE EUROPEAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT Meeting on New Developments in High Temperature Materials CY AUG 12-15, 1998 CL ISTANBUL, TURKEY DE diamond; molecular dynamics; nanophase; fracture; Si3N4 ID SILICON-NITRIDE; INTERFACES; FRACTURE; MACHINES AB 'Grand Challenge' atomistic simulations of high-temperature structural materials ave performed on multiple, parallel platforms. The simulations focus on sintering of ceramic nanoclusters, structure and mechanical properties of nanophase ceramics, and hypervelocity impact damage in diamond coatings. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Louisiana State Univ, Dept Comp Sci, Dept Phys & Astron, Concurrent Comp Lab Mat Simulat, Baton Rouge, LA 70803 USA. Yamaguchi Univ, Dept Appl Sci, Ube, Yamaguchi 7558611, Japan. RP Chatterjee, A (reprint author), Argonne Natl Lab, IPNS, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Tsuruta, Kenji/B-2131-2011 OI Tsuruta, Kenji/0000-0002-1447-2530 NR 16 TC 5 Z9 5 U1 1 U2 2 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. PY 1999 VL 19 IS 13-14 BP 2257 EP 2264 DI 10.1016/S0955-2219(99)00108-9 PG 8 WC Materials Science, Ceramics SC Materials Science GA 243PE UT WOS:000083005800008 ER PT J AU Dickey, EC Frazer, CS Watkins, TR Hubbard, CR AF Dickey, EC Frazer, CS Watkins, TR Hubbard, CR TI Residual stresses in high-temperature ceramic eutectics SO JOURNAL OF THE EUROPEAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT Meeting on New Developments in High Temperature Materials CY AUG 12-15, 1998 CL ISTANBUL, TURKEY DE residual stresses; ZrO(2)-NiO; Al(2)O(3)-YAG; eutectics; X-ray methods ID YTTRIUM-ALUMINUM-GARNET; CRYSTALLOGRAPHY; SOLIDIFICATION; INTERFACES; GRAINS AB This paper explores residual thermal stresses in directionally solidified ceramic eutectics, a class of materials that has much promise for high-temperature structural applications. Residual strain tensors of both phases in a eutectic composite are measured by single crystal X-ray diffraction techniques. In the analysis the material is treated as fully anisotropic and the strain tensors, subsequently converted to stress tensors, are measured Results are presented for two oxide eutectics, NiO-cubic ZrO(2) and YAG-Al(2)O(3), the former having a large thermal expansion mismatch between the two phases and the latter having similar thermal expansion properties. It is discovered that large residual stresses (of the order of 1 GPa) can be present at room temperature in as-processed eutectic materials unless the thermal expansion behaviors of the constituent materials are very similar. Ultimately these measurements not only elucidate the stress state but, when compared to theory, give information about the degree of interfacial constraint between the two phases. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Kentucky, Dept Chem & Mat Engn, Lexington, KY 40506 USA. Oak Ridge Natl Lab, Div Met & Ceram, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Dickey, EC (reprint author), Univ Kentucky, Dept Chem & Mat Engn, Lexington, KY 40506 USA. EM ecdickey@engr.uky.edu RI Dickey, Elizabeth/A-3368-2011; Watkins, Thomas/D-8750-2016 OI Dickey, Elizabeth/0000-0003-4005-7872; Watkins, Thomas/0000-0002-2646-1329 NR 31 TC 40 Z9 40 U1 1 U2 9 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. Eur. Ceram. Soc. PY 1999 VL 19 IS 13-14 BP 2503 EP 2509 DI 10.1016/S0955-2219(99)00100-4 PG 7 WC Materials Science, Ceramics SC Materials Science GA 243PE UT WOS:000083005800033 ER PT J AU Huser, T Novotny, L Lacoste, T Eckert, R Heinzelmann, H AF Huser, T Novotny, L Lacoste, T Eckert, R Heinzelmann, H TI Observation and analysis of near-field optical diffraction SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID LIGHT-PROPAGATION; MICROSCOPE ISTOM; TIP AB We present an experimental study of near-field optical interactions between an optical probe and sample objects with different dielectric properties. The interaction strongly affects the radiation emitted at angles beyond the critical angle of total internal reflection in the substrate (the forbidden light regime). Such an effect has been predicted theoretically. Our experimental data show that if a conducting object is close to the optical probe, p-polarized optical fields are deflected away from the object. On the other hand, s-polarized fields are deflected toward dielectric objects. The experimental results show good qualitative agreement with numerical simulations. The described effects have a strong influence on image formation in scanning near-field optical microscopy and thus have to be taken into account for image analysis. (C) 1999 Optical Society of America [S0740-3232(99)02201-2]. C1 Univ Basel, Inst Phys, CH-4056 Basel, Switzerland. Pacific NW Lab, Richland, WA 99352 USA. RP Heinzelmann, H (reprint author), Univ Basel, Inst Phys, Klingelbergstr 82, CH-4056 Basel, Switzerland. RI Huser, Thomas/H-1195-2012 OI Huser, Thomas/0000-0003-2348-7416 NR 17 TC 25 Z9 25 U1 0 U2 3 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3232 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD JAN PY 1999 VL 16 IS 1 BP 141 EP 148 DI 10.1364/JOSAA.16.000141 PG 8 WC Optics SC Optics GA 153MX UT WOS:000077837800014 ER PT J AU Kasunic, KJ Wright, EM AF Kasunic, KJ Wright, EM TI Nonlinear dynamics of circular-grating distributed-feedback semiconductor devices SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID PERIODIC STRUCTURES; OPTICAL-RESPONSE; GAP SOLITONS; LASERS; MODE; EQUATIONS; GAIN AB We report numerical results for the spatiotemporal dynamics of circular-grating distributed-feedback devices with an intensity-dependent refractive index. For the specific geometry and range of variables considered, we find that modulational instabilities do not propagate in these structures. This is due to the 1/r intensity distribution associated with cylindrical waves, which reduces the effectiveness of the self- and cross-phase-modulation nonlinearities. (C) 1999 Optical Society of America. [S0740-3224(99)01501- 5]. OCIS codes: 190.0190, 190.3270, 130.5990. C1 Univ Arizona, Ctr Opt Sci, Tucson, AZ 85721 USA. RP Kasunic, KJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Wright, Ewan/A-2358-2009 NR 19 TC 3 Z9 3 U1 0 U2 0 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 JAN PY 1999 VL 16 IS 1 BP 96 EP 102 DI 10.1364/JOSAB.16.000096 PG 7 WC Optics SC Optics GA 157NE UT WOS:000078067900014 ER PT J AU Di Lorenzo, ML Wunderlich, B AF Di Lorenzo, ML Wunderlich, B TI Temperature-modulated calorimetry of the crystallization of polymers analyzed by measurements and model calculations SO JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY LA English DT Article DE crystallization; heat capacity; heat-flow rate; temperature-modulated calorimetry ID DIFFERENTIAL SCANNING CALORIMETRY; GLASS-TRANSITION REGION; HEAT-CAPACITY; CRYSTALS AB The response of temperature-modulated differential scanning calorimetry (TMDSC) to irreversible crystallization of linear polymers was investigated by model calculations and compared to a number of measurements. Four different exotherms were added to a typical modulated, reversible heat-flow rate in order to simulate irreversible crystallization. It was found that the reversing heat-flow rate of the TMDSC in response to such irreversible crystallization exotherms is strongly affected by tbe shape of the transition and the phase-angle where the exotherm occurs. A comparison with the experimental data gave valuable insight into the transitions, as well as the nature of the TMDSC response which is usually limited to an analysis of the first harmonic term of the Fourier series that describes the heat-flow rate. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Di Lorenzo, ML (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RI Di Lorenzo, Maria Laura/N-5692-2015 NR 20 TC 24 Z9 24 U1 0 U2 5 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1418-2874 J9 J THERM ANAL CALORIM JI J. Therm. Anal. PY 1999 VL 57 IS 2 BP 459 EP 472 DI 10.1023/A:1010163923965 PG 14 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 251AZ UT WOS:000083423600007 ER PT J AU Glass, DE Merrigan, MA Sena, JT Camarda, CJ AF Glass, DE Merrigan, MA Sena, JT Camarda, CJ TI Startup and transient performance of a Nb-1%Zr potassium heat pipe SO JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER LA English DT Article C1 Analyt Serv & Mat Inc, Hampton, VA 23666 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 3 TC 2 Z9 2 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0887-8722 J9 J THERMOPHYS HEAT TR JI J. Thermophys. Heat Transf. PD JAN-MAR PY 1999 VL 13 IS 1 BP 153 EP 155 DI 10.2514/2.6414 PG 3 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 162TP UT WOS:000078363100020 ER PT J AU Wang, ZH Cohen, SA AF Wang, ZH Cohen, SA TI Hollow cathode magnetron SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID PLANAR MAGNETRON AB A new type of plasma sputtering device, named the hollow cathode magnetron (HCM), has been developed by surrounding a planar magnetron cathode with a hollow cathode structure. Operating characteristics of HCMs, current-voltage (I-V) curves for fixed discharge pressure and voltage-pressure (V-p) curves for fixed cathode current, are measured. Such characteristics are compared with their planar magnetron counterparts. New operation regimes, such as substantially lower pressures (0.3 mTorr), were discovered for HCMs. Cathode erosion profiles show marked improvement over planar magnetron in terms of material utilization. The use of HCMs for thin film deposition are discussed. (C) 1999 American Vacuum Society. [S0734-2101(99)00401-7]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Wang, ZH (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. EM zwang@pppl.gov NR 15 TC 17 Z9 17 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JAN-FEB PY 1999 VL 17 IS 1 BP 77 EP 82 DI 10.1116/1.581553 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 158UU UT WOS:000078136300011 ER PT J AU Chen, H Chattopadhyay, K Chen, KT Burger, A George, MA Gregory, JC Nag, PK Weimer, JJ James, RB AF Chen, H Chattopadhyay, K Chen, KT Burger, A George, MA Gregory, JC Nag, PK Weimer, JJ James, RB TI Passivation of CdZnTe surfaces by oxidation in low energy atomic oxygen SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 44th National Symposium of the American-Vacuum-Society CY OCT 20-24, 1997 CL SAN JOSE, CALIFORNIA SP Amer Vacuum Soc ID RAY PHOTOELECTRON-SPECTROSCOPY; CDTE SURFACES; ETCHANTS AB A method of surface passivation of Cd1-xZnxTe (CZT) x-ray and gamma ray detectors has been established by using microwave-assisted atomic oxygen bombardment. Detector performance is significantly enhanced due to the reduction of surface leakage current. CZT samples were exposed to an atomic oxygen environment at the University of Alabama in Huntsville's Thermal Atomic Oxygen Facility. This system generates neutral atomic oxygen species with kinetic energies of 0.1-0.2 eV. The surface chemical composition and its morphology modification due to atomic oxygen exposure were studied by x-ray photoelectron spectroscopy and atomic force microscopy and the results were correlated with current-voltage measurements and with room temperature spectral responses to Ba-133 and Am-241 radiation. A reduction of leakage current by about a factor of 2 is reported, together with significant improvement in the gamma-ray line resolution. (C) 1999 American Vacuum Society. [S0734-2101(99)00201-8]. C1 Fisk Univ, Dept Phys, Ctr Photon Mat & Devices, Nashville, TN 37208 USA. Univ Alabama, Dept Chem, Huntsville, AL 35899 USA. Sandia Natl Labs, Adv Elect Mfg Technol Dept, Livermore, CA 94550 USA. RP Chen, H (reprint author), Fisk Univ, Dept Phys, Ctr Photon Mat & Devices, Nashville, TN 37208 USA. EM mgeorge@matsci.uah.edu NR 11 TC 30 Z9 34 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JAN-FEB PY 1999 VL 17 IS 1 BP 97 EP 101 DI 10.1116/1.581557 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 158UU UT WOS:000078136300015 ER PT J AU Niles, DW Al-Jassim, M Ramanathan, K AF Niles, DW Al-Jassim, M Ramanathan, K TI Direct observation of Na and O impurities at grain surfaces of CuInSe2 thin films SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID ELECTRONIC-STRUCTURE; AUGER MICROPROBE; SOLAR-CELLS; SODIUM AB The authors use field-emission Auger electron spectroscopy to investigate the spatial nature of trace Na and O impurities in thin films of photovoltaic-grade CuInSe2 thin films. They give the first direct proof that Na and O reside at grain surfaces and not in the grain interiors of CuInSe2 (CIS) thin films, and discuss the improvement in photovoltaic conversion efficiency of CIS with Na. (C) 1999 American Vacuum Society. [S0734-2101(99)04401-2]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Niles, DW (reprint author), Hewlett Packard Co, MS64,3404 E Harmony Rd, Ft Collins, CO 80528 USA. NR 23 TC 65 Z9 65 U1 0 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JAN-FEB PY 1999 VL 17 IS 1 BP 291 EP 296 DI 10.1116/1.581583 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 158UU UT WOS:000078136300043 ER PT J AU Hamza, AV Schenkel, T Barnes, AV Schneider, DH AF Hamza, AV Schenkel, T Barnes, AV Schneider, DH TI Secondary ion coincidence in highly charged ion based secondary ion mass spectroscopy for process characterization SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article AB Coincidence counting in highly charged ion based secondary ion mass spectroscopy has been applied to the characterization of selective tungsten deposition via disilane reduction of tungsten hexafluoride on a patterned SiO2/Si wafer. The high secondary ion yield and the secondary ion emission from a small area produced by highly charged ions make the coincidence technique very powerful. [S0734-2101(99)03601-5]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Hamza, AV (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 9 TC 14 Z9 14 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JAN-FEB PY 1999 VL 17 IS 1 BP 303 EP 305 DI 10.1116/1.582026 PG 3 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 158UU UT WOS:000078136300045 ER PT J AU Reedy, RC Young, MR Asher, SE AF Reedy, RC Young, MR Asher, SE TI Low-cost modification for the high-frequency raster on the Cameca IMS-3F secondary ion mass spectrometer SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article AB The Cameca IMS-3F secondary ion mass spectrometry (SIMS) instrument, now three generations old, is still considered quality surface-analysis equipment. It was designed more than two decades ago, at a time when power transistors were the means of rastering high voltages at high frequencies. In our modification, we have replaced the high-frequency amplifiers with a simple operational amplifier (op amp) circuit that greatly enhances the capabilities of this instrument. In a Cameca dynamic SIMS instrument, the primary ion beam is focused into a small spot (similar to 5 - 100 mu m) and then is rastered over an area generally between 25 mu m x 25 mu m and 500 mu m x 500 mu m. The raster signal is a sawtooth waveform with separate high and low-frequency components for X and Y, respectively. The transistor design of the raster amplifier does not produce a sharp waveform at high frequencies. Instead, the signal appears rounded at the top and bottom. This, in turn, allows the ion beam to spend more time at the edges of the rastered area, etching the sides at a greater rate, producing the so-called "dog ears" at the bottom of the SIMS crater. Under most analysis conditions, these dog ears are not a problem because the analysis area is much smaller than the rastered area (e.g., a 60-mu m-diameter circular analysis area for a 250 mu m x 250 mu m rastered area) and is taken from the center. However, when the sputter depth is great, or the analysis area approaches the size of the rastered area, there is a loss of depth resolution. Another problem occurs when sputtering through thin films deposited on glass or other insulating materials. During depth profiling, as the material is sputtered away, the edges reach the insulator before the analysis area, which causes a charge buildup. The operator must then stop the profile prematurely, resulting in a loss of information. (C) 1999 American Vacuum Society. [S0734-2101(99)05201-X]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Reedy, RC (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 0 TC 1 Z9 1 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JAN-FEB PY 1999 VL 17 IS 1 BP 317 EP 318 DI 10.1116/1.581587 PG 2 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 158UU UT WOS:000078136300049 ER PT J AU Blain, MG Jarecki, RL Simonson, RJ AF Blain, MG Jarecki, RL Simonson, RJ TI Chemical downstream etching of tungsten (vol A16, pg 2115, 1998) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Correction C1 Sandia Natl Labs, Microelect Dev Lab, Albuquerque, NM 87185 USA. RP Blain, MG (reprint author), Sandia Natl Labs, Microelect Dev Lab, POB 5800, Albuquerque, NM 87185 USA. NR 1 TC 1 Z9 1 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JAN-FEB PY 1999 VL 17 IS 1 BP 323 EP 323 DI 10.1116/1.581590 PG 1 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 158UU UT WOS:000078136300052 ER PT J AU Zhang, LQ Dailey, PJ He, T Gettie, A Bonhoeffer, S Perelson, AS Ho, DD AF Zhang, LQ Dailey, PJ He, T Gettie, A Bonhoeffer, S Perelson, AS Ho, DD TI Rapid clearance of simian immunodeficiency virus particles from plasma of rhesus macaques SO JOURNAL OF VIROLOGY LA English DT Article ID ERYTHROCYTE COMPLEMENT RECEPTOR; MONONUCLEAR PHAGOCYTE SYSTEM; IN-VIVO; HIV-1 INFECTION; ANTIRETROVIRAL THERAPY; MONKEY MODEL; DYNAMICS; LYMPHOCYTES; LYSIS AB Perturbation of the equilibrium between human immunodeficiency virus type 1 (HIV-1) and the infected host by administering antiretroviral agents has revealed the rapid turnover of both viral particles and productively infected cells. In this study, we used the infusion of simian immunodeficiency virus (SIV) particles into rhesus macaques to obtain a more accurate estimate of viral clearance in vivo. Consistently, exogenously infused virions were cleared from plasma with an extremely short half-life, on the order of minutes (a mean of 3.3 min). This new estimate is similar to 100-fold lower than the upper bound of 6 h previously reported for HIV-1 in infected humans. In select animals, multiple tissues were collected at the completion of each experiment to track the potential sites of virion clearance. Detectable levels of SIV RNA were found in lymph nodes, spleen, lungs, and liver, but not in other tissues examined. However, only similar to 1 to 10% or less of the infused virions were accounted for by the thorough tissue sampling, indicating that the vast majority of the infused particles must have been degraded over a short period of time. Should the rapid clearance of virions described here be applicable to infected patients, then HIV-I production and thus the number of productively infected CD4(+) T lymphocytes or the viral burst size must be proportionally higher than previous minimal estimates. C1 Rockefeller Univ, Aaron Diamond AIDS Res Ctr, New York, NY 10016 USA. Chiron Corp, Emeryville, CA 94608 USA. Univ Oxford, Dept Zool, Oxford OX1 3PS, England. ETH Zurich, Expt Ecol, Zurich, Switzerland. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM USA. RP Ho, DD (reprint author), Rockefeller Univ, Aaron Diamond AIDS Res Ctr, 455 1st Ave,7th Floor, New York, NY 10016 USA. RI Bonhoeffer, Sebastian/A-2735-2008 OI Bonhoeffer, Sebastian/0000-0001-8052-3925 FU NIAID NIH HHS [AI40387] NR 30 TC 70 Z9 70 U1 0 U2 0 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0022-538X J9 J VIROL JI J. Virol. PD JAN PY 1999 VL 73 IS 1 BP 855 EP 860 PG 6 WC Virology SC Virology GA 146YP UT WOS:000077461700103 PM 9847402 ER PT J AU Kilkenny, JD Bernat, TP Hammel, BA Kauffman, RL Landen, OL Lindl, JD MacGowan, BJ Paisner, JA Powell, HT AF Kilkenny, JD Bernat, TP Hammel, BA Kauffman, RL Landen, OL Lindl, JD MacGowan, BJ Paisner, JA Powell, HT TI Lawrence Livermore National Laboratory's activities to achieve ignition by X-ray drive on the National Ignition Facility SO LASER AND PARTICLE BEAMS LA English DT Article; Proceedings Paper CT 25th European Conference on Laser Interaction with Matter (ECLIM) CY MAY 04-08, 1999 CL FORMIA, ITALY SP Assoc EURATOM-ENEA, Frascati ICF Phys & Technol Lab ID INDIRECTLY DRIVEN; LASER FUSION; SYMMETRY; PLASMA; NOVA; IMPLOSIONS; DEUTERIUM; HOHLRAUMS; TRITIUM; DESIGN AB The National Ignition Facility (NIF) is a MJ-class glass laser-based facility funded by the Department of Energy which has achieved thermonuclear ignition and moderate gain as one of its main objectives. In the summer of 1998, the project was about 40% complete, and design and construction was on schedule and on cost. The NIF will start firing onto targets in 2001, and will achieve full energy in 2004. The Lawrence Livermore National Laboratory (LLNL) together with the Los Alamos National Laboratory (LANL) have the main responsibility for achieving X-ray driven ignition on the NIF In the 1990s, a comprehensive series of experiments on Nova at LLNL, followed by recent experiments on the Omega laser at the University of Rochester, demonstrated confidence in understanding the physics of X-ray drive implosions. The same physics at equivalent scales is used in calculations to predict target performance on the NIF, giving credence to calculations of ignition on the NIF An integrated program of work in preparing the NIF for X-ray driven ignition in about 2007, and the key issues being addressed on the current Inertial Confinement Fusion (ICF) facilities [(Nova, Omega, Z at Sandia National Laboratory (SNL) and NIKE at the Naval Research Laboratory (NRL)], are described. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Kilkenny, JD (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-488, Livermore, CA 94550 USA. NR 34 TC 13 Z9 13 U1 0 U2 2 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 PY 1999 VL 17 IS 2 BP 159 EP 171 PG 13 WC Physics, Applied SC Physics GA 217VE UT WOS:000081518900003 ER PT J AU Dittrich, TR Haan, SW Marinak, MM Hinkel, DE Pollaine, SM McEachern, R Cook, RC Roberts, CC Wilson, DC Bradley, PA Varnum, WS AF Dittrich, TR Haan, SW Marinak, MM Hinkel, DE Pollaine, SM McEachern, R Cook, RC Roberts, CC Wilson, DC Bradley, PA Varnum, WS TI Capsule design for the National Ignition Facility SO LASER AND PARTICLE BEAMS LA English DT Article; Proceedings Paper CT 25th European Conference on Laser Interaction with Matter (ECLIM) CY MAY 04-08, 1999 CL FORMIA, ITALY SP Assoc EURATOM-ENEA, Frascati ICF Phys & Technol Lab ID TRITIUM AB Several choices exist in the design and production of capsules intended to ignite and propagate fusion burn of the deuterium-tritium (D-T) fuel when imploded by indirect drive at the National Ignition Facility (NIF). These choices include ablator material, ablator dopant concentration and distribution, capsule dimensions, and X-ray drive profile (shock timings and strengths). The choice of ablator material must also include fabrication and material characteristics, such as attainable surface finishes, permeability, strength, transparency to radio frequency and infrared radiation, thermal conductivity, and material homogeneity. Understanding the advantages and/or limitations of these choices is an ongoing effort for LLNL and LANL designers. At this time, simulations in one-, two-, and three-dimensions show that capsules with either a copper-doped beryllium or a polyimide (C22H10N2O4) ablator material have both the least sensitivity to initial surface roughnesses and favorable fabrication qualities. Simulations also indicate the existence of capsule designs based on these ablator materials which ignite and burn when imploded by less than nominal laser performance (900-kJ energy, 250-TW power, producing 250-eV peak radiation temperature). We will describe and compare these reduced-scale capsules, in addition to several designs which use the expected 300-eV peak X-ray drive obtained from operating the NIF laser at 1.3 MJ and 500 TW. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Alamos Natl Lab, Albuquerque, NM USA. RP Dittrich, TR (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 15 TC 16 Z9 18 U1 1 U2 2 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 PY 1999 VL 17 IS 2 BP 217 EP 224 PG 8 WC Physics, Applied SC Physics GA 217VE UT WOS:000081518900008 ER PT J AU Montgomery, DS Johnson, RP Cobble, JA Fernandez, JC Lindman, EL Rose, HA Estabrook, KG AF Montgomery, DS Johnson, RP Cobble, JA Fernandez, JC Lindman, EL Rose, HA Estabrook, KG TI Characterization of plasma and laser conditions for single hot spot experiments SO LASER AND PARTICLE BEAMS LA English DT Article; Proceedings Paper CT 25th European Conferece on Laser Interaction with Matter (ECLIM 1998) CY MAY 07, 1998 CL FORMIA, ITALY ID STIMULATED BRILLOUIN-SCATTERING; F-NUMBER; DEPENDENCE; INTENSITY AB The TRIDENT laser system at the Los Alamos National Laboratory is being used for fundamental experiments which study the interaction of self-focusing, stimulated Raman scattering (SRS) and stimulated Brillouin scattering (SBS) in a near-diffraction-limited (single) laser hot Spot in order to better understand the coupling between these plasma instabilities. The diffraction limited beam mimics a single hot spot found in speckle distributions that are typical of random or kinoform phase plates (RPP or KPP) used for spatial smoothing of laser beams. A long scale length, hot plasma (similar to 1 mm, similar to 0.6 keV) is created by a separate heater beam, and the single hot spot beam is used to drive parametric instabilities. The focal: plane distribution and wave-front of the interaction beam are characterized, and its intensity can be varied between 10(14)-10(16) W/cm(2). The plasma density, temperature, and flow profiles are measured using a gated imaging spectroscopy of collective Thomson scattering from the heater beam. Results of the laser and plasma characterization, and initial results of backscattered:SRS, SBS, and beam steering in a flowing plasma are presented. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Montgomery, DS (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Fernandez, Juan/H-3268-2011; OI Fernandez, Juan/0000-0002-1438-1815; Montgomery, David/0000-0002-2355-6242 NR 11 TC 38 Z9 38 U1 0 U2 2 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 PY 1999 VL 17 IS 3 BP 349 EP 359 PG 11 WC Physics, Applied SC Physics GA 272UX UT WOS:000084670300001 ER PT J AU Tubbs, DL Barnes, CW Beck, JB Hoffman, NM Oertel, JA Watt, RG Boehly, T Bradley, D Knauer, J AF Tubbs, DL Barnes, CW Beck, JB Hoffman, NM Oertel, JA Watt, RG Boehly, T Bradley, D Knauer, J TI Direct-drive cylindrical implosion experiments: Simulations and data SO LASER AND PARTICLE BEAMS LA English DT Article; Proceedings Paper CT 25th European Conferece on Laser Interaction with Matter (ECLIM 1998) CY MAY 07, 1998 CL FORMIA, ITALY AB We have studied a suite of cylindrical, polystyrene targets, both unperturbed and with mode-28, 1.5 mu m initial-amplitude sinusoidal perturbations imposed azimuthally along the target length. All targets are driven by direct laser illumination at 3 omega using the University of Rochester OMEGA laser facility. Our numerical simulation and experimental data demonstrate the proof of principle for direct-drive studies of complex hydrodynamic phenomena in convergent geometry. We obtain high-quality, time-dependent data, that demonstrate good implosion symmetry and against which numerical simulations show promising agreement within currently assessed error bars. Our results identify operational space for continuing experiments. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Rochester, Laser Energet Lab, Rochester, NY USA. RP Tubbs, DL (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 4 TC 4 Z9 5 U1 4 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 PY 1999 VL 17 IS 3 BP 437 EP 449 PG 13 WC Physics, Applied SC Physics GA 272UX UT WOS:000084670300011 ER PT J AU Labaune, C Baldis, HA Bauer, BS Schifano, E Michard, A AF Labaune, C Baldis, HA Bauer, BS Schifano, E Michard, A TI Effect of crossed beams irradiation on parametric instabilities SO LASER AND PARTICLE BEAMS LA English DT Article; Proceedings Paper CT 25th European Conferece on Laser Interaction with Matter (ECLIM 1998) CY MAY 07, 1998 CL FORMIA, ITALY ID STIMULATED BRILLOUIN-SCATTERING; SELF-PHASE MODULATION; LASER-BEAMS; ENERGY-TRANSFER; PLASMA AB Modification of the growth of scattering processes in the case of multiple beam irradiation compared to single beam irradiation has been investigated in a preformed plasma using Thomson scattering of a short wavelength probe beam, and spectral and temporal analysis of re flected and transmitted light. First observations of the reduction of the amplitude of ion acoustic waves associated with simulated Brillouin scattering, amplification of,the amplitude of electron plasma waves associated with stimulated Raman scattering, and transfer of energy between crossing beams with same frequency in a flowing plasma under-crossed beam irradiation are reported. C1 Ecole Polytech, CNRS, Lab Utilisat Lasers Intenses, F-91128 Palaiseau, France. Univ Calif Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. RP Labaune, C (reprint author), Ecole Polytech, CNRS, Lab Utilisat Lasers Intenses, F-91128 Palaiseau, France. NR 16 TC 0 Z9 0 U1 0 U2 0 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 PY 1999 VL 17 IS 3 BP 451 EP 457 PG 7 WC Physics, Applied SC Physics GA 272UX UT WOS:000084670300012 ER PT J AU Cowan, TE Perry, MD Key, MH Ditmire, TR Hatchett, SP Henry, EA Moody, JD Moran, MJ Pennington, DM Phillips, TW Sangster, TC Sefcik, JA Singh, MS Snavely, RA Stoyer, MA Wilks, SC Young, PE Takahashi, Y Dong, B Fountain, W Parnell, T Johnson, J Hunt, AW Kuhl, T AF Cowan, TE Perry, MD Key, MH Ditmire, TR Hatchett, SP Henry, EA Moody, JD Moran, MJ Pennington, DM Phillips, TW Sangster, TC Sefcik, JA Singh, MS Snavely, RA Stoyer, MA Wilks, SC Young, PE Takahashi, Y Dong, B Fountain, W Parnell, T Johnson, J Hunt, AW Kuhl, T TI High energy electrons, nuclear phenomena and heating in petawatt laser-solid experiments SO LASER AND PARTICLE BEAMS LA English DT Article; Proceedings Paper CT 25th European Conference on Laser Interaction with Matter (ECLIM 1998) CY MAY 07, 1998 CL FORMIA, ITALY AB The Petawatt laser at Lawrence Livermore National Laboratory (LLNL) has opened a new regime of laser matter interactions in which the quiver motion of plasma electrons is fully relativistic with energies extending well above the threshold for nuclear processes. In addition to similar to few MeV ponderomotive electrons produced in ultra intense laser-solid interactions, we have found a high energy component of electrons extending to similar to 100 MeV apparently from relativistic selffocusing and plasma acceleration in the underdense preformed plasma. The generation of hard bremsstrahlung, photonuclear reactions, and preliminary evidence for positron-electron pair production will be discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Alabama, Huntsville, AL 35899 USA. George C Marshall Space Flight Ctr, Huntsville, AL 35899 USA. Univ Space Res Assoc, Huntsville, AL 35806 USA. Harvard Univ, Cambridge, MA 02138 USA. Gesell Schwerionenforsch GmbH, D-6100 Darmstadt, Germany. RP Cowan, TE (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Kuhl, Thomas/C-2243-2012; Cowan, Thomas/A-8713-2011 OI Kuhl, Thomas/0000-0001-6306-4579; Cowan, Thomas/0000-0002-5845-000X NR 20 TC 114 Z9 117 U1 0 U2 6 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 PY 1999 VL 17 IS 4 BP 773 EP 783 PG 11 WC Physics, Applied SC Physics GA 309EJ UT WOS:000086755100023 ER PT S AU Williams, RM Beck, KM Joly, AG Dickinson, JT Hess, WP AF Williams, RM Beck, KM Joly, AG Dickinson, JT Hess, WP BE Dubowski, JJ Helvajian, H Kreutz, EW Sugioka, K TI Pulse-width influence on laser induced desorption of positive ions from ionic solids SO LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Applications in Microelectronic and Optoelectronic Manufacturing IV CY JAN 25-27, 1999 CL SAN JOSE, CA SP USAF Off Sci Res, SPIE DE MgO; magnesium oxide; laser ablation; laser induced desorption; ultrafast laser; ionic solids; ionic crystals; wide bandgap insulators; ultrafast processes; multi-photon processes ID GAP SINGLE-CRYSTALS; EMISSION; MGO; SUBPICOSECOND; RADIATION; SURFACES AB We have compared the desorption of positive ions, including Mg+ and MgO+, from ionic magnesium oxide (MgO) single crystals following pulsed laser excitation using either nanosecond (3 ns, 266 nm) or femtosecond (similar to 300 fs, 265 nm) sources. Following optical excitation, desorbed ions are rapidly extracted and mass analyzed using standard time-of-flight techniques. Ion yields and velocities are determined as a function of laser fluence. The threshold similarity is a surprising result, as sub-band gap nanosecond pulses are only likely to excite defect states efficiently (via linear excitation), while the ultrahigh peak-power femtosecond pulses could in principle induce multiphoton and avalanche excitation. We argue that at least in this specific case, the important factor appears to be merely the number of photons and not the pulse duration. However, it is observed that femtosecond excitation yields considerable H+ and less interference from impurity alkali ions than does nanosecond excitation. The source of the protons is presumably the hydroxylated MgO surface. C1 EMSL, Pacific NW Natl Lab, Richland, WA 99352 USA. RP Hess, WP (reprint author), EMSL, Pacific NW Natl Lab, MS K8-88,POB 999, Richland, WA 99352 USA. NR 12 TC 3 Z9 3 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3088-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3618 BP 37 EP 44 DI 10.1117/12.352727 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Coatings & Films; Optics SC Engineering; Materials Science; Optics GA BN65R UT WOS:000082492400005 ER PT S AU Chang, JJ McLean, W Dragon, EP Warner, BE AF Chang, JJ McLean, W Dragon, EP Warner, BE BE Dubowski, JJ Helvajian, H Kreutz, EW Sugioka, K TI Emission spectra and particle ejection during visible-laser ablation of graphite for diamond-like coatings SO LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Applications in Microelectronic and Optoelectronic Manufacturing IV CY JAN 25-27, 1999 CL SAN JOSE, CA SP USAF Off Sci Res, SPIE DE pulsed laser deposition; laser ablation; diamond-lice coatings; laser plasma ID CARBON-FILMS; DEPOSITION; DEPENDENCE; PRESSURE AB We have investigated the emission spectra of a carbon plume generated from graphite by a visible pulsed laser for diamond-like coatings (DLC). The laser utilized was a 300-watt class copper vapor laser with a pulse duration of similar to 40 ns. To better understand the laser-target interaction, we have visualized plume dynamics near the graphite surface via Schelieren method. We found that the laser ablation process was accompanied with explosive material ejection during pulsed laser deposition (PLD). The ejection of material started at about 500 ns after the onset of laser pulse and lasted for about 10 mu s. The material ejection is very directional and introduced large amount of micro particulates in the DLC film. We have found that the use of a random phase plate to smooth the laser intensity profile effectively eliminated this election of material with additional advantage of higher coating rate. The spectra in the visible and UV of the plume emission were analyzed to correlate with DLC quality and coating rate. We have characterized the carbon plasma based on emissions from C, C-2, C+ and C++ for laser peak intensities between 0.1 - 5 GW/cm(2). We have produced high-quality DLC with its coating rate optimized at laser peak power densities between 0.5 GW/cm(2) and 0.8 GW/cm(2). The kinetic energy of C+ was estimated to be similar to 20 eV at this optimized coating condition. We found that greater C+ kinetic energy at higher laser intensity does not necessarily produce better DLC. This process optimization enabled us to demonstrate a coating rate as high as 2000 mu m-cm(2)/hr. The C-2 swan-band emission from the plume was most pronounced in the optimized coating condition and was used as a process diagnostic tool. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Chang, JJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,M-S L-463, Livermore, CA 94550 USA. NR 16 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3088-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3618 BP 71 EP 80 DI 10.1117/12.352710 PG 10 WC Engineering, Electrical & Electronic; Materials Science, Coatings & Films; Optics SC Engineering; Materials Science; Optics GA BN65R UT WOS:000082492400009 ER PT S AU Dylla, HF AF Dylla, HF BE Dubowski, JJ Helvajian, H Kreutz, EW Sugioka, K TI An overview of the user program for the Jefferson Lab Free Electron Laser SO LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Applications in Microelectronic and Optoelectronic Manufacturing IV CY JAN 25-27, 1999 CL SAN JOSE, CA SP USAF Off Sci Res, SPIE AB Jefferson Lab is commissioning a high-average-power infrared IR FEL during 1998. When driven with its superconducting linac operating in a recirculated mode, the IR Demo FEL is capable of producing kilowatt-level average power in the midinfrared (2-7 microns) range. With operational experience and hardware changes involving primarily change-out of the optical cavity mirrors, the FEL is capable of covering a wide range of the infrared (1-16 microns) at power levels exceeding 100 watts. This tuning range combined with a unique pulse structure (ps micropulses at 37 MHz) makes the Jefferson Lab FEL a versatile research and development tool for a wide variety of laser applications. A core group of industrial partners has been involved in planning applications using the FEL since 1991. This initial user group was augmented with university partners in 1993 and with participants from several national laboratories in 1996-1997. With the initiation of construction of the FEL and the associated 600 m(2) user facility laboratory in 1996, a number of topical user groups were formed to plan and implement the first series of user experiments. The industrial partners have formed user groups planning applications in polymer surface processing, metal surface processing, microfabrication, and electronic materials. University partners have submitted proposals on basic science topics which complement the planned applied research topics, in addition to proposing experiments in atomic physics, chemical physics and materials science which take advantage of one or more of the unique characteristics of the FEL. A synopsis of the proposed user experiments for the first phase of operation of the Jefferson Lab FEL Mill be presented. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Dylla, HF (reprint author), Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 37 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3088-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3618 BP 388 EP 395 DI 10.1117/12.352700 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Coatings & Films; Optics SC Engineering; Materials Science; Optics GA BN65R UT WOS:000082492400043 ER PT S AU Merkulov, VI Lowndes, DH Baylor, LR Jellison, GE Puretzky, AA Geohegan, DB AF Merkulov, VI Lowndes, DH Baylor, LR Jellison, GE Puretzky, AA Geohegan, DB BE Dubowski, JJ Helvajian, H Kreutz, EW Sugioka, K TI Pulsed-laser deposited amorphous diamond and related materials: Synthesis, characterization, and field emission properties SO LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING IV SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Laser Applications in Microelectronic and Optoelectronic Manufacturing IV CY JAN 25-27, 1999 CL SAN JOSE, CA SP USAF Off Sci Res, SPIE DE diamond; tetrahedral amorphous carbon; pulsed laser ablation; EELS; ellipsometry; field emission ID 2-MODULATOR GENERALIZED ELLIPSOMETRY; CARBON-FILMS AB Amorphous carbon films with variable sp(3) content were produced by ArF (193nm) pulsed laser deposition. An in-situ ion probe was used to measure kinetic energy of C(+) ions. In contrast to measurements made as a function of laser fluence, ion probe measurements of kinetic energy are a convenient as well as more accurate and fundamental method for monitoring deposition conditions, with the advantage of being readily transferable for inter-laboratory comparisons. Electron energy loss spectroscopy (EELS) and spectroscopic ellipsometry measurements reveal that tetrahedral amorphous carbon (ta-C) films with the most diamond-like properties are obtained at the C ion kinetic energy of similar to 90 eV. Film properties are uniform within a 12-15 degrees angle from the plume centerline. Tapping-mode atomic force microscope measurements show that films deposited at near-optimum kinetic energy are extremely smooth, with rms roughness of only similar to 1 Angstrom over distances of several hundred nm. Field emission (FE) measurements show that ta-C does not appear to be a good electron emitter. After conditioning of ta-C films deposited on n-type Si a rather high turn-on voltage of similar to 50 V/mu m was required to draw current of similar to 1 nA to the probe. The emission was unstable and typically ceased after a few minutes of operation. The FE tests of ta-C and other materials strongly suggest that surface morphology plays a dominant role in the FE process, in agreement with conventional Fowler-Nordheim theory. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Merkulov, VI (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Puretzky, Alexander/B-5567-2016; Geohegan, David/D-3599-2013 OI Puretzky, Alexander/0000-0002-9996-4429; Geohegan, David/0000-0003-0273-3139 NR 34 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3088-9 J9 PROC SPIE PY 1999 VL 3618 BP 495 EP 503 DI 10.1117/12.352708 PG 9 WC Engineering, Electrical & Electronic; Materials Science, Coatings & Films; Optics SC Engineering; Materials Science; Optics GA BN65R UT WOS:000082492400054 ER PT J AU Schoonover, JR AF Schoonover, JR TI Time-resolved, step-scan FTIR studies of excited states of d(6) metal polypyridine complexes SO LASER CHEMISTRY LA English DT Article; Proceedings Paper CT 8th International Conference on Time-Resolved Vibrational Spectroscopy CY APR 07-11, 1997 CL OXFORD, ENGLAND SP AG Electro-Opt, Andor Technol Ltd/LOT Oriel, Bruker Spectrospin Ltd, Clarke-MXR Inc, Coherent (UK) Ltd, Edinburgh Instruments Ltd/Continuum, Mutek Infrared Laser Syst GmbH, Photox Opt Syst, Princeton Instruments Ltd, Renishaw plc, Rutherford Appleton Lab CLRC, Spectra-Phys Lasers Ltd DE time-resolved infrared; step-scan infrared; excited state; d(6) metal polypyridine complexes ID INFRARED-SPECTROSCOPY; ELECTRONIC-STRUCTURE; TRANSITION; CHEMISTRY; LIGAND AB Time-resolved infrared spectroscopy using step-scan FTIR has been developed as an approach to study transient inorganic species with lifetimes ranging from ca. 200 nanseconds to several microseconds. This approach has been applied to a variety of problems arising following laser excitation of d(6) polypyridine complexes in solution, and several examples are shown to demonstrate the utility of this experiment. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Schoonover, JR (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, POB 1663, Los Alamos, NM 87545 USA. NR 15 TC 1 Z9 1 U1 3 U2 3 PU HARWOOD ACAD PUBL GMBH PI READING PA C/O STBS LTD, PO BOX 90, READING, BERKS, ENGLAND RG1 8JL SN 0278-6273 J9 LASER CHEM JI Laser Chem. PY 1999 VL 19 IS 1-4 BP 263 EP 269 DI 10.1155/1999/36437 PG 7 WC Chemistry, Physical SC Chemistry GA 215EY UT WOS:000081370000045 ER PT S AU Weakley, SC Stolz, CJ Wu, ZL Bevis, RP von Gunten, MK AF Weakley, SC Stolz, CJ Wu, ZL Bevis, RP von Gunten, MK BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Role of starting material composition in interfacial damage morphology of hafnia silica multilayer coatings SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE flat bottom pits; coating interfaces; reactive e-beam evaporation; hafnia silica multilayers ID LASER-INDUCED DAMAGE; POLARIZER COATINGS; THIN-FILMS; MIRROR AB Flat bottom pits, previously shown to be unstable above a critical fluence, may be impacted by interfacial characteristics of the multilayer. TEM cross-sections reveal multilayer coatings deposited from hafnium have fewer interfacial voids than those deposited from hafnia. To correlate this reduction with the occurrence of flat bottom pits, multilayer high reflectors deposited by reactive electron-beam evaporation from both metallic and oxide sources were damage tested with 3-ns, 1064-nm pulses. To shift the electric-field peaks to the adjacent interface, half of the samples included an additional buried half-wave of silica in their all quarter-wave design. All quarter-wave reflectors deposited from hafnia had flat bottom pit damage in the outer six layers at fluences of 20 J/cm(2). Interfacial damage also occurred in hafnium deposited coatings at fluences as low as 20 J/cm(2), but at significantly different depths. The only interfacial damage observed on the all quarter-wave coatings was at the substrate multilayer interface. Flat bottom pits were observed in the buried half-wave coatings with a correlation to electric-field position and preference to interface type. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Weakley, SC (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-487, Livermore, CA 94550 USA. NR 14 TC 13 Z9 13 U1 0 U2 6 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 137 EP 143 DI 10.1117/12.344420 PG 7 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000018 ER PT S AU Stolz, CJ Sheehan, LM Maricle, SM Schwartz, S Hue, J AF Stolz, CJ Sheehan, LM Maricle, SM Schwartz, S Hue, J BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI A study of laser conditioning methods of hafnia silica multilayer mirrors SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE laser conditioning; laser-induced damage; laser damage morphology; hafnia-silica multilayer coating ID ATOMIC-FORCE MICROSCOPY; POLARIZER COATINGS; INDUCED DAMAGE AB A variety of 1064-nm laser conditioning methods were investigated to find the optimum method for production of large aperture (0.25 m(2)) multilayer coatings for the National Ignition Facility and Laser MegaJoule. Two conditioning methods were explored, multi-step and single-step on two different laser systems. Off-line conditioning was done on PLATO, a small beam diameter (similar to 1 mm) raster scanning system. On-line conditioning was done on Beamlet, a single beam prototype of the National Ignition Facility with a large rectangular beam (35 cm x 35 cm). Concurrent with this work, coating process development for low-defect density high damage threshold coatings was realized by switching from hafnia to hafnium starting materials. The results of this study suggest that single-step raster-scan off-line laser conditioning is an effective method to raise the damage threshold of multilayer miners deposited from. hafnium and silica by reactive electron beam deposition. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Stolz, CJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-487, Livermore, CA 94550 USA. NR 14 TC 17 Z9 17 U1 0 U2 7 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 144 EP 153 DI 10.1117/12.344419 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000019 ER PT S AU Feit, MD Rubenchik, AM Kozlowski, MR Genin, FY Schwartz, S Sheehan, LM AF Feit, MD Rubenchik, AM Kozlowski, MR Genin, FY Schwartz, S Sheehan, LM BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Extrapolation of damage test data to predict performance of large-area NIF optics at 355 nm SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE laser initiated damage; statistics; large optics ID STRENGTH AB For the aggressive fluence requirements of the NIF laser, some level of laser-induced damage to the large (40x40 cm) 351 nm final optics is inevitable. Planning and utilization of NIF therefore requires reliable prediction of the functional degradation of the final optics. Laser damage tests are typically carried out with Gaussian beams on relatively small test areas. The tests yield a damage probability vs. energy fluence relation. These damage probabilities are shown to depend on both the beam fluence distribution and the size of area tested. Thus, some analysis is necessary in order to use these test results to determine expected damage levels for large aperture optics. We present a statistical approach which interprets the damage probability in terms of an underlying intrinsic surface density of damaging defects. This allows extrapolation of test results to different sized areas and different beam shapes (NIF has a flattop beam). The defect density is found to vary as a power of the fluence (Weibull distribution). C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Feit, MD (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 E Ave,Ms L-439, Livermore, CA USA. RI Feit, Michael/A-4480-2009 NR 8 TC 37 Z9 37 U1 1 U2 8 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 226 EP 234 DI 10.1117/12.344413 PG 9 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000028 ER PT S AU Runkel, M AF Runkel, M BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Monte Carlo simulation of the R/1 automated damage test SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE Monte Carlo simulation; damage testing; KDP; fused silica AB In this paper, a Monte Carlo computer analysis of the R/1 automated damage test procedure currently in use at LLNL is presented. This study was undertaken to quantify the intrinsic sampling errors of the R/1 ADT method for various types of optical materials, particularly KDP and fused silica, and to provide a recommended minimum number of test sites. A gaussian/normal distribution of 10 J/cm(2) average fluence (CL) was used as a damage distribution model. The standard deviation to) of the distribution was varied to control its shape. Distributions were simulated which correspond to the damage distributions of KDP (mu/sigma = 5-10) and fused silica (mu/sigma similar to 15). A measure of the variability in test results was obtained by random sampling of these distributions and construction of the cumulative failure probability "S" curves. The random samplings were performed in runs of 100 "tests" with the number of samples (i.e. sites) per test ranging from 2 to 500. For distributions with mu/sigma = 5-10, the study found an intrinsic error of 3 to 5% in the maximum deviation from the distribution average when using 100 site tests. The computations also showed substantial variation in the form of the CFD for any given test. The simulation results were compared to actual data from eight 100 site R/1 automated tests on a sample from rapidly grown KDP. It was found that while each 100 site damage probability curve could be fit to a gaussian distribution reasonably well, the 800 site cumulative damage probability curve was better modeled by a lognormal distribution. The differences observed in the individual CFD curves could be accounted for by sampling errors calculated from gaussian models. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Runkel, M (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 5 TC 2 Z9 2 U1 2 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 277 EP 289 DI 10.1117/12.344457 PG 13 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000034 ER PT S AU Sheehan, L Schwartz, S Battersby, C Dickson, R Jennings, R Kimmons, J Kozlowski, M Maricle, S Mouser, R Runkel, M Weinzapfel, C AF Sheehan, L Schwartz, S Battersby, C Dickson, R Jennings, R Kimmons, J Kozlowski, M Maricle, S Mouser, R Runkel, M Weinzapfel, C BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Automated damage test facilities for materials development and production optic quality assurance at Lawrence Livermore National Laboratory SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE automated damage testing; R : 1 mapping; raster scan; damage diagnostics ID LASER AB The Laser Program at LLNL has developed automated facilities for damage testing optics ul to 1 meter in diameter. The systems were developed to characterize the statistical distribution of localized damage performance across large-aperture National Ignition Facility optics, Full aperture testing is a key component of the quality assurance program for several of the optical components. The primary damage testing methods used are R:1 mapping and raster scanning.;Automation of these test methods was required to meet the optics manufacturing schedule. The automated activities include control and diagnosis of the damage-test laser beam as well as detection and characterization of damage events. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Sheehan, L (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-496, Livermore, CA 94550 USA. NR 7 TC 4 Z9 5 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 302 EP 313 DI 10.1117/12.344447 PG 12 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000036 ER PT S AU Schwartz, S Feit, MD Kozlowski, MR Mouser, RP AF Schwartz, S Feit, MD Kozlowski, MR Mouser, RP BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Current 3 omega large optic test procedures and data analysis for the quality assurance of national ignition facility optics SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE laser damage; laser damage metrology; NIF metrology; National Ignition Facility; large area testing; 3 omega damage testing AB A reliable metric is required to describe; the damage resistance of large aperture 3 omega transmissive optics for the NIF laser. The trend fi-om single site testing to the more statistically valid Gaussian scanning test requires a well modeled experimental procedure, accurate monitoring of the test parameters, and careful interpretation of the resulting volumes of data. The methods described here provide reliable quality assurance data, as well as intrinsic damage concentration information used to predict the performance expected under use conditions. This paper describes the equipment, test procedure, and data analysis used to evaluate large aperture 3 omega optics for the NIF laser. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Schwartz, S (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-496, Livermore, CA 94551 USA. RI Feit, Michael/A-4480-2009 NR 1 TC 15 Z9 15 U1 1 U2 7 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 314 EP 321 DI 10.1117/12.344417 PG 8 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000037 ER PT S AU Runkel, M Williams, W DeYoreo, J AF Runkel, M Williams, W DeYoreo, J BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Predicting bulk damage in NIF triple harmonic generators SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE KDP; KD*P; bulk damage; damage prediction AB Recently reported experiments(1,2) have investigated the statistics of laser damage in KDP and KD*P, Automated damage tests have allowed cumulative failure and damage probability distributions to be constructed. Large area tests have investigated-the feasibility of on-line laser conditioning and damage evolution for tripler harmonic generation (THG) crystals on the National Ignition Facility (NIF). These tests have shown that there is a nonzero probability of damage at NIF redline fluence (14.3 J/cm(2), 351 nm, 3 ns) and that the damage pinpoint density evolves exponentially with fluence. In this paper, the results of these tests are used in conjunction with model spatial profiles of the NIF beam to predict the level of damage created in the THG crystal. A probabilistic calculation based on the overlap of the beam fluence and damage probability distribution shows that the overall damage probability is less than 3% for well-conditioned, high quality KDP/KD*P crystals of conventional or rapid growth. The number density of generated pinpoints has been calculated by mapping the damage evolution curves onto the NIF model profile. This shows that the number of damage pinpoints generated in high fluence portions of the NIF beam will be low for well-conditioned THG crystals. In contrast, unconditioned triplers of the same material will exhibit an increase in pinpoint density of greater than 20X. To test the validity of these calculations a 37 cm, conventionally grown KD*P tripler from, the Beamlet laser was: scatter mapped for bulk damage. The tripler had been exposed to NIF-like fluences during its operational lifetime on Beamlet and exhibited very low levels of bulk pinpoint damage, essentially supporting the predictions based on tests and modeling. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Runkel, M (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-250, Livermore, CA 94550 USA. NR 8 TC 2 Z9 2 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 322 EP 335 DI 10.1117/12.344456 PG 14 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000038 ER PT S AU Britten, JA Herman, SM Summers, LJ Rushford, MC Auyang, L Barton, IM Shore, BW Dixit, SN Parham, TG Hoaglan, CR Thompson, CT Battersby, CL Yoshiyama, JM Mouser, RP AF Britten, JA Herman, SM Summers, LJ Rushford, MC Auyang, L Barton, IM Shore, BW Dixit, SN Parham, TG Hoaglan, CR Thompson, CT Battersby, CL Yoshiyama, JM Mouser, RP BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Manufacture, optical performance and laser damage characteristics of diffractive optics for the national ignition facility SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE gratings; diffraction; antireflective coatings; wet etching ID COLOR SEPARATION; SILICA; GRATINGS AB We have fabricated demonstration diffractive optic plates (DOP's) at full scale for the National Ignition Facility (NIF) laser. These include an off-axis focusing beam sampling grating, a color separation grating, and a kinoform phase plate for spatial beam smoothing. Fabrication methods and optical performance of these DOP's are discussed. It was discovered that the sol-gel antireflective coating normally applied to high-power transmissive optics partially planarizes the diffractive structures, particularly on the color separation grating used for color management at target, to the extent that optical performance and laser damage threshold are negatively impacted. The effect of sol-gel coatings on sating performance, the feasability of placing all diffractive structures on a single surface, and future work in this area are discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Britten, JA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 12 TC 12 Z9 13 U1 2 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 337 EP 346 DI 10.1117/12.344461 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000040 ER PT S AU Kozlowski, MR Mouser, R Maricle, S Wegner, P Weiland, T AF Kozlowski, MR Mouser, R Maricle, S Wegner, P Weiland, T BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Laser Damage performance of fused silica optical components measured on the Beamlet Laser at 351 nm SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE laser damage; fused silica; polishing; NIF; growth rate; defects; inclusions AB A statistics-based model is being developed to predict the laser-damage-limited lifetime of UV optical components on the NIF laser. In order to provide data for the model, laser damage experiments were performed on the Beamlet laser system at LLNL (aperture: 34 cm x 34 cm). Three prototype NIF focus lenses were exposed to 351 nm pulses (1.5ns or 3ns) during four experimental campaigns, each consisting of 23 to 38 pulses at NIF relevant fluences. Each lens was sol-gel AR coated and all laser exposures were performed in a vacuum environment. Through inspections of the lens before, during and after the campaigns, pulse-to-pulse damage growth rates were measured for damage initiating both on the surfaces and at bulk inclusions. Radial growth rates measured for rear surface damage was typically 10x higher than that measured in the bulk or at the front surface. No significant correlation of growth rate to precursor type was indicated. For 5 J/cm(2), 3 us pulses the typical radial growth rate was nominally 20 mu m/pulse. Average growth rates measured on three lenses made by two manufacturers were in good agreement. While the growth rate clearly increased with fluence, the data obtained was insufficient to quantify the dependence. The growth rates reported here were 20x -50x higher than values predicted from offline studies of bare surfaces in air. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Kozlowski, MR (reprint author), Univ Calif Lawrence Livermore Natl Lab, 700 East Ave, Livermore, CA 94551 USA. NR 7 TC 20 Z9 20 U1 0 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 436 EP 445 DI 10.1117/12.344415 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000051 ER PT S AU Battersby, CL Sheehan, LM Kozlowski, MR AF Battersby, CL Sheehan, LM Kozlowski, MR BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Effects of wet etch processing on laser-induced damage of fused silica surfaces SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE laser-induced damage; fused silica; wet etch; hydrogen fluoride; TIRM; microscopy AB Laser-induced damage of transparent fused silica optical components by 355 nm illumination occurs primarily at surface defects produced during the grinding and polishing processes, These defects can either be surface defects or sub-surface damage. Wet etch processing in a buffered hydrogen fluoride (HF) solution has been examined as a tool for characterizing such defects. A study was conducted to understand the effects of etch depth on the damage threshold of fused silica substrates. The study used a 355 nm, 7.5 ns, 10 Hz Nd:YAG laser to damage test fused, silica optics through various wet. etch processing steps. Inspection of the surface quality was performed with Nomarski microscopy and Total Internal Reflection Microscopy. The damage test data and inspection results were correlated with polishing process specifics. The results show that a wet etch exposes sub-surface damage while maintaining or improving the laser damage performance. The benefits of a wet etch must be evaluated for each polishing process. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Battersby, CL (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-496, Livermore, CA 94550 USA. NR 7 TC 21 Z9 21 U1 0 U2 11 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 446 EP 455 DI 10.1117/12.344412 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000052 ER PT S AU Salleo, A Chinsio, R Genin, FY AF Salleo, A Chinsio, R Genin, FY BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Crack propagation in fused silica during UV and IR ns-laser illumination SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL ID INDUCED DAMAGE; TRANSPARENT DIELECTRICS; PULSES; PICOSECOND AB The functional lifetime of large-aperture optical components used an a laser such as the National Ignition Facility is an important engineering parameter. To predict the lifetime of fused silica transmissive optics, it is necessary to measure the rate of damage propagation as a function of fluence and understand the effects of the laser parameters (e.g. wavelength and pulse width). In order to begin such predictions without a large-area flat-top laser beam, damage growth experiments were conducted using a small (1 mm diameter) Gaussian beam. Damage was initiated by producing mechanical flaws on the surface of the optic. Since output surface damage in transmissive optics can propagate at least two orders of magnitude faster than input surface damage, the experiments were focused on damage initiated at the output surface. The experiments showed that if damage was initiated, it could nor grow at fluences below a threshold of about 5 and 8 J/cm(2) at 355 and 1064 nm, respectively. When damage was able to propagate under laser irradiation, the phenomenon occurred in two stages. Initially, the damage grew both laterally and along the optical axis at a rate varying linearly with fluence (stage I). Lateral growth stopped in areas where the fluence was lower than the growth threshold. At this point, the area of damage typically filled the size of the beam and the rate of axial damage propagation significantly decreased. During this stage (stage II), laser irradiation drilled at constant rate a channel through the window. During stage I, the damage area grew much faster at 355 nm than at 1064 nm. During stage IX, 355 nm light drilled four to five times faster than 1064 nm light. At a given fluence at 1064 nm, the drilling rate did not change between 3 ns and 10 ns. Finally, drilling at 1064 nm produced a well-defined cylindrical damaged region while 355 MI light generated less regular clusters of cracks. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Salleo, A (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 15 TC 12 Z9 12 U1 0 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 456 EP 471 DI 10.1117/12.344416 PG 16 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000053 ER PT S AU Ferris, KF Exarhos, GJ Risser, SM AF Ferris, KF Exarhos, GJ Risser, SM BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Time evolved optical properties of liquid crystalline molecules SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE electronic structure; molecular dynamics; liquid crystals; dynamic fluctuations ID INTERNAL-ROTATION; BIPHENYL; OPTIMIZATION; PLANAR AB While many studies have focused on the computation of static properties of small organic molecules, dynamic fluctuations can introduce important perturbations to the electronic structure and subsequent optical properties. In this paper, we present results from combined molecular dynamics/quantum mechanical calculations on the linear and nonlinear optical properties of 5-alkyl-cyanobiphenyl (5CB) molecule. As opposed to the static structure commonly used in computations of optical properties, the dynamic picture requires a number of configurations with unique optical properties. As an example, the torsion angle (phi) between the phenyl rings in the optimal static picture is 40.1 degrees, but is better described as a probability distribution in the time dependent problem. Simulations of the nematic phase using periodic boundary conditions further emphasize the importance of these fluctuations on the electronic structure of this system. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Ferris, KF (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999, Richland, WA 99352 USA. NR 17 TC 0 Z9 0 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 487 EP 495 DI 10.1117/12.344443 PG 9 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000057 ER PT S AU Demos, SG Staggs, M Yan, M Radousky, HB De Yoreo, JJ AF Demos, SG Staggs, M Yan, M Radousky, HB De Yoreo, JJ BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Observation of photoexcited emission clusters in the bulk of KDP and laser conditioning under 355-nm irradiation SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE KDP; fluorescence microscopy; spectroscopy; damage ID POTASSIUM DIHYDROGEN PHOSPHATE; KH2PO4 CRYSTALS; DAMAGE AB Defect clusters in the bulk of large KDP crystals are revealed using a microscopic fluorescence imaging system and CW laser illumination. Exposure of the crystal to high power 355-nm, 3-ns laser irradiation leads to a significant reduction of the number of observed optically active centers. The initially observed defect cluster concentration is approximately 10(4)-10(6) per mm(3) depending on the crystal growth method and sector of the crystal. The number of defect clusters can be reduced by a mm factor of 10(2) or more under exposure to 355-nm laser irradiation while their average intensities also decreases. Spectroscopic measurements provide information on the electronic structure of the defects. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94580 USA. RP Demos, SG (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94580 USA. NR 14 TC 3 Z9 3 U1 2 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 509 EP 515 DI 10.1117/12.344402 PG 7 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000060 ER PT S AU Bozlee, BW Exarhos, GJ Teel, RW AF Bozlee, BW Exarhos, GJ Teel, RW BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Spectroscopic studies of pulsed laser-induced damage sites in heated CaF2 crystals SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE calcium fluoride; colloid; color center; laser damage; mie theory; Raman spectroscopy; stress; temperature ID SINGLE-CRYSTALS AB Based upon previous studies of temperature dependent defect state formation in high energy alpha particle irradiated CaF2, analogous temperature dependent effects were expected to occur when heated crystals were exposed to Q-switched emission from a pulsed Nd:YAG laser. It was shown in the alpha-irradiation work that optimum clustering of calcium atoms to form colloids would occur at a critical temperature. In recent work, irradiation of isothermally heated crystals at fluences on the order of 1 J/cm(2) produced both catastrophic mechanical damage to the crystal as well as localized defect states within the lattice. Below 200 degrees C the mechanical damage was severe, as evidenced by extensive fractures radiating from the damage center along the crystal cleavage planes. However, above 200 degrees C, these fracture lines were absent and more localized damage was seen. Raman spectra measured within the damage footprint revealed the presence of CaF2 lattice forbidden bands associated with calcium colloids in addition to a blue shift of the principal T-2g CaF2 mode frequency. The T-2g line shift signifies the presence of compressive stress (approximately 7 kbar) in the CaF2 lattice induced by the presence of the calcium colloids. Forbidden phonon line intensities varied with Raman probe wavelength, and the associated Raman excitation profile followed the wavelength response of the optical absorption band at 580 nm, which is ascribed to colloid resonance absorption. The presence of colloid was detected at all temperatures, and the extent of colloid formation was found to be only weakly dependent upon the crystal temperature. This lack of sensitivity may be ascribed to highly localized heating of the crystal surface during the laser pulse, which could supersede the effect of ambient temperature. Pulsed Raman studies of thin CaF2 sections at laser fluences just below the damage threshold did indeed indicate temperature excursions within the laser footprint. For samples held at temperatures above 200 degrees C, the color centers were found to absorb more strongly in the 400-500 nm and NIR regions, probably indicating greater aggregation of F centers in the crystal. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Bozlee, BW (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999, Richland, WA 99352 USA. NR 26 TC 1 Z9 1 U1 2 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 533 EP 543 DI 10.1117/12.344449 PG 11 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000064 ER PT S AU Wu, ZL Feit, MD Kozlowski, M Natoli, JY Rubenchik, AM Sheehan, L Yan, M AF Wu, ZL Feit, MD Kozlowski, M Natoli, JY Rubenchik, AM Sheehan, L Yan, M BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Single-beam photothermal microscopy - a new diagnostic tool for optical materials SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE single beam photothermal microscopy; laser modulated scattering; nondestructive evaluation; characterizations of defects; laser-induced damage; optical-surfaces and thin film coatings ID INTERNAL-REFLECTION MICROSCOPY; FUSED-SILICA SURFACES; LASER DAMAGE; COATINGS; 355-NM AB A novel photothermal microscopy (PTM) is developed which uses only one laser beam, working as both the pump and the probe. The principle of this single-beam PTM is based on the detection of the second harmonic component of the laser modulated scattering (LMS) signal. This component has a linear dependence on the optical absorptance of the tested area and a quadratic dependence an the pump laser power. Using a pump laser at the wavelengths of 514.5- and 532-nm high-resolution photothermal scans are performed for polished fused silica surfaces and a HfO2/SiO2 multilayer coatings. The results are compared with those from the traditional two-beam PTM mapping. It is demonstrated that the single-beam PTM is more user-friendly (i.e. no alignment is needed) than conventional two-beam PTM and, offers a higher spatial resolution for defect detection. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wu, ZL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Feit, Michael/A-4480-2009 NR 17 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 604 EP 613 DI 10.1117/12.344423 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000072 ER PT S AU Whitman, PK Bletzer, K Hendrix, JL Genin, FY Hester, M Yoshiyama, J AF Whitman, PK Bletzer, K Hendrix, JL Genin, FY Hester, M Yoshiyama, J BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Laser-induced damage of absorbing and diffusing glass surfaces under IR and UV irradiation SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE laser-induced damage; beam dump; surface morphology; absorbing glass; 355 nm; 1064 nm AB In high peak power lasers used for inertial confinement fusion experiments, scattered and reflected light can carry sufficient energy to ablate metal structures or even damage other optics. Absorbing and diffuse scattering materials are required to manage the "ghosts", stimulated Raman scattering (SRS) and unconverted light in the laser chain and target chamber. Absorbing and diffuse scattering glasses were investigated for use in the NIF target chamber to safely dissipate up 60 - 80 J/cm(2) 1053-nm light while also withstanding up to 2 J/cm(2) of soft x-ray. In addition these glasses were evaluated for use at 1053-nm and 351-nm to dissipate stray light and to absorb stimulated Raman scattering from the conversion crystals. Glass samples with surfaces ranging from specular to highly scattering (etched, sandblasted) were evaluated. The morphologies of laser damage at 1064 nm and 355 nm were characterized by Nomarski optical microscopy. Laser damage was quantified by measuring mass loss. Surface treatment and bulk absorption coefficient were the two material properties most strongly correlated to laser damage. Etched and sandblasted surfaces always had lower damage threshold than their specular counterparts. Reducing rear surface fluence either by bulk absorption or scattering at the input surface delayed the onset of catastrophic failure under extreme (60 J/cm(2)) conditions. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Whitman, PK (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 8 TC 3 Z9 3 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 681 EP 691 DI 10.1117/12.344421 PG 11 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000080 ER PT S AU Sheehan, L Wu, ZL Kozlowski, MR AF Sheehan, L Wu, ZL Kozlowski, MR BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Defect characterization on super-polished fused silica surfaces polished for high power laser applications at 355 nm SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Meeting Abstract CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 694 EP 694 DI 10.1117/12.344418 PG 1 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000082 ER PT S AU Yan, M Oberhelman, S Siekhaus, W Wu, ZL Sheehan, L Kozlowski, M AF Yan, M Oberhelman, S Siekhaus, W Wu, ZL Sheehan, L Kozlowski, M BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Characterization of surface and sub-surface defects in optical materials using near field evanescent wave SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Meeting Abstract CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 718 EP 720 DI 10.1117/12.344425 PG 3 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000085 ER PT S AU Wu, ZL Feit, MD Kozlowski, MR Rubenchik, AM Sheehan, L AF Wu, ZL Feit, MD Kozlowski, MR Rubenchik, AM Sheehan, L BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Laser modulated scattering as a nondestructive evaluation tool for optical surfaces and thin film coatings SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE laser modulated scattering; nondestructive evaluation; characterizations of defects; laser-induced damage; polished surfaces and thin film coatings ID INTERNAL-REFLECTION MICROSCOPY; PHOTOTHERMAL DEFLECTION; DAMAGE; SILICA AB Laser modulated scattering (LMS) is introduced as a non-destructive evaluation tool for defect inspection and characterization of optical surfaces and thin film coatings. This technique is a scatter sensitive version of the well-known photothermal microscopy (PTM) technique. It allows simultaneous measurement of the DC and AC scattering signals of a probe laser beam from an optical surface. By comparison between the DC and AC scattering signals, one can differentiate absorptive defects from non-absorptive ones. This paper describes the principle of the LMS technique and the experimental setup, and illustrates examples on using LMS as a tool for nondestructive evaluation of high quality optics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wu, ZL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Feit, Michael/A-4480-2009 NR 17 TC 2 Z9 2 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 721 EP 729 DI 10.1117/12.344422 PG 9 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000086 ER PT S AU Thomas, N Erlandson, A Farmer, J Gregg, H Marshall, C Siekhaus, W Wolfe, J Fix, D Ahre, D AF Thomas, N Erlandson, A Farmer, J Gregg, H Marshall, C Siekhaus, W Wolfe, J Fix, D Ahre, D BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Protected silver coatings for flashlamp-pumped Nd : glass amplifiers SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE Proceedings of SPIE LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL ID CORROSION AB A durable protected silver coating(1,2) was designed and fabricated for possible use on flashlamp reflectors in the National Ignition Facility (NIF) to avoid tarnishing under corrosive conditions and intense visible light (10 J/cm(2), 360 mu s). This coating provides a valuable alternative for mirror coatings where high reflectance and durability are important requirements. This paper describes a protected silver coating having high reflectance from 400 nm to 10,000 nm. The specular reflectance is between 95% and 98% in the visible region and 98% or better in the infrared region. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, 7000 E Ave, Livermore, CA 94550 USA. NR 16 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 PROC SPIE PY 1999 VL 3578 BP 730 EP 736 DI 10.1117/12.344462 PG 7 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000087 ER PT S AU Setchell, RE AF Setchell, RE BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Effects of accelerated aging on fiber damage thresholds SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL DE fiber optics; fiber damage; accelerated aging; static fatigue; CO2-laser conditioning; diffractive optics AB Laser-induced damage mechanisms that can occur during high-intensity fiber transmission have been under study for a number of years. Our particular interest in laser initiation of explosives has led us to examine damage processes associated with the transmission of Q-switched, Nd:YAG pulses at 1.06 mu m through step-index, multimode, fused silica fiber. Laser breakdown at the fiber entrance face is often the first process to limit fiber transmission, but catastrophic damage can also occur at either fiber end face, within the initial "entry" segment of the fiber, and at other internal sites along the fiber path. Past studies have examined how these various damage mechanisms depend upon fiber end-face preparation, fiber fixturing and routing, laser characteristics, and laser-to-fiber injection optics. In some applications of interest, however, a fiber transmission system may spend years in storage before it is used. Consequently, an important additional issue for these applications is whether or not there are aging processes that can result in lower damage thresholds over time. Fiber endface contamination would certainly lower breakdown and damage thresholds at these surfaces, but careful design of hermetic seals in connectors and other end-face fixtures can minimize this possibility. A more subtle possibility would be a process for the slow growth of internal defects that could lead to lower thresholds for internal damage. In the current study, two approaches to stimulating the growth of internal defects were used in an attempt to produce observable changes in internal damage thresholds. In the first approach, test fibers were subjected to a very high tensile stress for a time sufficient for some fraction to fail from static fatigue. In the second approach, test fibers were subjected to a combination of high tensile stress and large, cyclic temperature variations. Both of these approaches were rather arbitrary due to the lack of an established growth mechanism for internal defects. Damage characteristics obtained from fibers subjected to each of these aging environments were compared to results from fresh fibers tested under identical conditions. A surprising result was that internal damage was not observed in any of the tested fibers. Only breakdown at the fiber entrance face and catastrophic damage at both end faces were observed. Fiber end faces were not sealed during the accelerated aging environments, and thresholds at these faces were significantly lower in the aged fibers. However, most fibers transmitted relatively high pulse energies before damaging, and a large fraction never damaged before we reached the limits of our test laser. The absence of any observable affect on internal damage thresholds is encouraging, but the current results do not rule out the possibility that some other approach to accelerated aging could reveal a growth mechanism for internal defects. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Setchell, RE (reprint author), Sandia Natl Labs, MS1421, Albuquerque, NM 87185 USA. NR 12 TC 5 Z9 5 U1 2 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 743 EP 752 DI 10.1117/12.344411 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000089 ER PT S AU Paisner, JA AF Paisner, JA BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI The effect of laser-induced damage on the national ignition facility optical design SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Meeting Abstract CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL C1 Univ Calif Lawrence Livermore Natl Lab, Natl Ignit Facil, Livermore, CA 94551 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 768 EP 770 DI 10.1117/12.344426 PG 3 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000092 ER PT S AU Demos, SG Staggs, M Radousky, HB De Yoreo, JJ AF Demos, SG Staggs, M Radousky, HB De Yoreo, JJ BE Schaffers, KI Myers, LE TI Investigation of steady-state and transient defect populations in KH2PO4 subsequent to high fluence laser irradiation SO LASER MATERIAL CRYSTAL GROWTH AND NONLINEAR MATERIALS AND DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Material Crystal Growth and Nonlinear Materials and Devices CY JAN 27-28, 1999 CL SAN JOSE, CA SP SPIE DE KDP; fluorescence microscopy; spectroscopy; defects; high power lasers ID POTASSIUM DIHYDROGEN PHOSPHATE AB Microscopic fluorescence imaging and time-resolved Raman scattering are employed to investigate the effect of high power 355 nm laser irradiation on preexisting and transient defect populations in KH2PO4. Defect clusters in the bulk of KDP crystals are imaged with 1 micron spatial resolution using their NIR emission. The intensity of the emission clusters varies widely within the image field. The exposure of the crystal at high power 355 nm, 3 ns laser irradiation leads to a reduction of the number of observed optically active centers. In addition, time resolved Raman scattering was employed to study the transient generation of defects during high power 355 nm laser irradiation. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94580 USA. RP Demos, SG (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94580 USA. NR 9 TC 1 Z9 1 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3080-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3610 BP 2 EP 8 DI 10.1117/12.349237 PG 7 WC Crystallography; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics; Physics, Applied SC Crystallography; Engineering; Materials Science; Optics; Physics GA BN19X UT WOS:000081054100001 ER PT S AU Kuczewski, AJ Thorn, CE Matone, G Giordano, G AF Kuczewski, AJ Thorn, CE Matone, G Giordano, G BE Schaffers, KI Myers, LE TI Production of high-power CWUV by resonant frequency quadrupling of a Nd : YLF laser SO LASER MATERIAL CRYSTAL GROWTH AND NONLINEAR MATERIALS AND DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Material Crystal Growth and Nonlinear Materials and Devices CY JAN 27-28, 1999 CL SAN JOSE, CA SP SPIE DE resonant cavity; high power UV; second harmonic generation; frequency quadrupling; BBO; LBO ID YAG LASER; GENERATION; CAVITY AB We have constructed a single ring to resonantly double an 18 watt Nd:YLF mode-locked laser and re-double the stored green to produce over 4 watts of power in the ultra-violet (UV). This laser is used to produce a beam of 470 MeV gamma-rays by Compton backscattering the laser beam from 2.8 GeV electrons stored in a synchrotron. Achieving high luminosity of the colliding beams requires very good mode quality and beam stability at the intersection point 22 meters from the laser. The ring consists of six mirrors, with two 25 cm radius of curvature mirrors enclosing each nonlinear crystal. The drive laser is a lamp-pumped Nd:YLF with a 50 ps bunch length at 76 MHz. A pointing stabilizer servo has been constructed as part of the infrared (IR) mode matching telescope. The IR to green conversion is accomplished in a 15 mm long non-critically phased matched LBO crystal located at a 40 micron waist, with an IR conversion efficiency of 70%. A stable, nearly diffraction limited UV beam of up to 4.2 watts is generated in a BBO crystal in the green storage ring. The output power is relatively independent of the efficiency of the LBO and BBO crystals. This fact makes it possible to reduce the amount of non-TEM, modes created by walk-off of the UV by using relatively thin BBO crystals. At present, however, the lower bound on the BBO thickness is limited by the loss of conversion efficiency at high power. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Kuczewski, AJ (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 10 TC 1 Z9 1 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3080-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3610 BP 57 EP 68 DI 10.1117/12.349220 PG 12 WC Crystallography; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics; Physics, Applied SC Crystallography; Engineering; Materials Science; Optics; Physics GA BN19X UT WOS:000081054100008 ER PT J AU Collins, CB Davanloo, F Iosif, MC Dussart, R Hicks, JM Karamian, SA Ur, CA Kirischuk, VI Carroll, JJ Roberts, HE McDaniel, P Crist, CE AF Collins, CB Davanloo, F Iosif, MC Dussart, R Hicks, JM Karamian, SA Ur, CA Kirischuk, VI Carroll, JJ Roberts, HE McDaniel, P Crist, CE TI Evidence for the forced gamma emission from the 31-year isomer of hafnium-178 SO LASER PHYSICS LA English DT Article AB A sample containing 0.63 x 10(15) nuclei of the 4 quasiparticle isomer of Hf-178 having a half life of 31 years and excitation energy of 2.45 MeV was irradiated with X-ray pulses derived from a commercial X-ray unit typically used in dental medicine, it was operated at 15 mA to produce Bremsstrahlung radiation with an endpoint energy of 90 keV, With a high purity Ge detector the number of gamma photons collected from transitions between the lower members of the ground state band was found to increase by about 2% above that emitted by spontaneous decay of the isomer, Such an enhancement is consistent with an integrated cross section of 2 x 10(-21) cm(2) keV, a value in agreement with results scaled from comparable measurements for Ta-180. However, this is believed to be the first observation of photon initiated gamma emission, with a substantial gain in energy. This result has considerable significance to the development of a gamma-ray laser. C1 Univ Texas Dallas, Ctr Quantum Elect, Richardson, TX 75080 USA. Joint Inst Nucl Res, Dubna 141980, Russia. HH Natl Inst Phys & Nucl Engn, Bucharest, Romania. Nucl Res Inst, Ctr Sci, Kiev, Ukraine. Youngstown State Univ, Dept Phys & Astron, Ctr Photon Induced Proc, Youngstown, OH 44555 USA. SRS Technol, Syst Technol Grp, Huntsville, AL USA. DEPA, AF Res Lab, Kirtland AFB, Albuquerque, NM USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Univ Texas Dallas, Ctr Quantum Elect, Richardson, TX 75080 USA. EM cbc@utdallas.edu NR 5 TC 28 Z9 30 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 1054-660X EI 1555-6611 J9 LASER PHYS JI Laser Phys. PD JAN-FEB PY 1999 VL 9 IS 1 BP 8 EP 11 PG 4 WC Optics; Physics, Applied SC Optics; Physics GA 171DX UT WOS:000078848200003 ER PT S AU Ray, MD Sedlacek, AJ AF Ray, MD Sedlacek, AJ BE Kamerman, GW Werner, C TI Mini-Raman lidar system for stand-off, in situ interrogation of surface contaminants SO LASER RADAR TECHNOLOGY AND APPLICATIONS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Radar Technology and Applications IV CY JUN 16, 1999 CL MUNICH, GERMANY SP Soc Photo Opt Instrumentat Engineers, European Opt Soc, Commiss European Communities, Directorate Gen Sci Res & Dev, Wissenschaftl Gesell Lasertech e V DE Raman; lidar; surface; portable; chemical sensor; contamination; non-contact; stand-off; in-situ AB The Mini-Raman Lidar System (MRLS) is a "proof-of-principle" chemical sensor that combines the spectral fingerprinting of solar-blind UV Raman spectroscopy with the principles of lidar to open a new venue of short-range (meters to tens of meters), non-contact detection and identification of unknown substances on surfaces. The device has potential application to "first responders" at the site of a chemical spill. The MRLS is portable and has been used both in the lab and in the field. Theoretical estimates and actual laboratory data suggest the possibility of detecting contaminants with a surface coverage of < 1g/m(2) at a distance of three meters for one second of signal integration. Increasing the optical throughput efficiency, integrating pattern recognition software, and incorporating a laser with a wavelength near 250 nm are the primary goals for the development of a prototype system. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ray, MD (reprint author), Brookhaven Natl Lab, Bldg 703, Upton, NY 11973 USA. NR 10 TC 2 Z9 2 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3181-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3707 BP 138 EP 147 DI 10.1117/12.351337 PG 10 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BN20D UT WOS:000081059300013 ER PT S AU Cooke, BJ Galbraith, AE Laubscher, BE Strauss, CE Olivas, NL Grubler, AC AF Cooke, BJ Galbraith, AE Laubscher, BE Strauss, CE Olivas, NL Grubler, AC BE Kamerman, GW Werner, C TI Laser field imaging through Fourier transform heterodyne SO LASER RADAR TECHNOLOGY AND APPLICATIONS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Radar Technology and Applications IV CY JUN 16, 1999 CL MUNICH, GERMANY SP Soc Photo Opt Instrumentat Engineers, European Opt Soc, Commiss European Communities, Directorate Gen Sci Res & Dev, Wissenschaftl Gesell Lasertech e V DE coherent field imaging; laser imaging; laser radar; heterodyne detection AB We present a detection process capable of directly imaging the transverse amplitude, phase, and Doppler shift of coherent electromagnetic fields. Based on coherent detection principles governing conventional heterodyned RADAR/LADAR systems, Fourier Transform Heterodyne incorporates transverse spatial encoding of the reference local oscillator for image capture. Appropriate selection of spatial encoding functions allows image retrieval by way of classic Fourier manipulations. Of practical interest: (i) imaging may be accomplished with a single element detector/sensor requiring no additional scanning or moving components, (ii) as detection is governed by heterodyne principles, near quantum limited performance is achievable, (iii) a wide variety of appropriate spatial encoding functions exist that may be adaptively configured in real-time for applications requiring optimal detection, and (iv) the concept is general with the applicable electromagnetic spectrum encompassing the RF through optical. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cooke, BJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS-D448, Los Alamos, NM 87545 USA. NR 19 TC 0 Z9 0 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3181-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3707 BP 390 EP 408 DI 10.1117/12.351361 PG 19 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BN20D UT WOS:000081059300038 ER PT S AU Martinez, MD Skulina, KM Deadrick, FJ Crane, JK Moran, B Braucht, J Jones, B Hawkins, S Tilley, R Crawford, J Browning, D Penko, F AF Martinez, MD Skulina, KM Deadrick, FJ Crane, JK Moran, B Braucht, J Jones, B Hawkins, S Tilley, R Crawford, J Browning, D Penko, F BE Kudryashov, AV TI Performance results of the high gain, Nd : Glass, engineering prototype preamplifier module (PAM) for the National Ignition Facility (NIF) SO LASER RESONATORS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Resonators II CY JAN 27-29, 1999 CL SAN JOSE, CA SP SPIE DE NIF; Nd : Glass; diode pumped; pre-amplifier; SSD AB We describe recent, energetics performance results on the engineering preamplifier module (PAM) prototype located in the front end of the 1.8MJ National Ignition Facility (NIF) laser system. Three vertically mounted subsystem located in the PAM provide laser gain as well as spatial beam shaping. The first subsystem in the PAM prototype is a diode pumped, Nd:glass, linear, TEM00, 4.5m long regenerative amplifier cavity. With a single diode pumped head, we amplify a 1nJ, mode matched, temporally shaped (approximate to 20ns) seed pulse by a factor of approximately 10(7) to 20mJ. The second subsystem in the PAM is the beam shaping module, which magnifies the gaussian output beam of the regenerative amplifier to provide a 30mm X 30mm square beam that is spatially shaped in two dimensions to pre-compensate for radial gain profiles in the main amplifiers. The final subsystem in the PAM is the 4-pass amplifier which relay images the 1mJ output of the beam shaper through four gain passes in a phi 5cm X 48cm flashlamp pumped rod amplifier, amplifying the energy to 17J. The system gain of the PAM is 10(10). Each PAM provides 3J of injected energy to four separate main amplifier chains which in turn delivers 1.8MJ in 192 frequency converted laser beams to the target for a broad range of laser fusion experiments. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Martinez, MD (reprint author), Univ Calif Lawrence Livermore Natl Lab, MS L-483 7000 E Ave, Livermore, CA 94550 USA. NR 9 TC 3 Z9 3 U1 1 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3081-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3611 BP 169 EP 180 DI 10.1117/12.349266 PG 12 WC Optics; Physics, Applied SC Optics; Physics GA BN13W UT WOS:000080851100019 ER PT S AU London, RA AF London, RA BE Jacques, SL Muller, GJ Roggan, A Sliney, DH TI Numerical simulations of a diode laser BPH treatment system SO LASER-TISSUE INTERACTION X: PHOTOCHEMICAL, PHOTOTHERMAL, AND PHOTOMECHANICAL, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser-Tissue Interaction X - Photochemical, Photothermal, and Photomechanical CY JAN 24-27, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc AB Numerical simulations are presented of the laser-tissue interaction of a diode laser system for treating benign prostate hyperplasia. The numerical model includes laser light transport, heat transport, cooling due to blood perfusion, thermal tissue damage, and enthalpy of tissue damage. Comparisons of the simulation results to clinical data are given. We report that a reasonable variation from a standard set of input data produces heating times which match those measured in the clinical trials. A general trend of decreasing damage volume with increasing heating time is described. We suggest that the patient-to-patient variability seen in the data can be explained by differences in fundamental biophysical properties such as the optical coefficients. Further work is identified, including the measurement and input to the model of several specific data parameters such as optical coefficients, blood perfusion cooling rate, and coagulation rates. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP London, RA (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 5508, Livermore, CA 94550 USA. NR 7 TC 3 Z9 3 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3071-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3601 BP 141 EP 155 DI 10.1117/12.349997 PG 15 WC Engineering, Biomedical; Immunology; Medicine, Research & Experimental; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Immunology; Research & Experimental Medicine; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BN29E UT WOS:000081436500020 ER PT S AU Makarewicz, AJ Visuri, S London, RA Miller, DS AF Makarewicz, AJ Visuri, S London, RA Miller, DS BE Jacques, SL Muller, GJ Roggan, A Sliney, DH TI Modeling optically-generated focused stress waves SO LASER-TISSUE INTERACTION X: PHOTOCHEMICAL, PHOTOTHERMAL, AND PHOTOMECHANICAL, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser-Tissue Interaction X - Photochemical, Photothermal, and Photomechanical CY JAN 24-27, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE computer modeling; stress waves; acoustic focusing AB Stress waves generated at the end of optical fibers through thermoelastic expansion have been used for several purposes, including the destruction of blood clots, the destruction of kidney and gallstones, and the induction of cell permeability changes for drug delivery. We have undertaken the modeling of stress wave propagation in an effort to optimize the stress wave effects in these therapies. In particular, we have studied techniques to focus the stress wave in order to increase the pressure magnitude for a given pulse energy and to alter the compressive/tensile pressure ratio. This study includes the effects of acoustic wavelength and focusing fiber tip shape. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Makarewicz, AJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3071-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3601 BP 207 EP 211 DI 10.1117/12.350003 PG 5 WC Engineering, Biomedical; Immunology; Medicine, Research & Experimental; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Immunology; Research & Experimental Medicine; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BN29E UT WOS:000081436500025 ER PT S AU Godwin, RP Chapyak, EJ Noack, J Vogel, A AF Godwin, RP Chapyak, EJ Noack, J Vogel, A BE Jacques, SL Muller, GJ Roggan, A Sliney, DH TI Aspherical bubble dynamics and oscillation times SO LASER-TISSUE INTERACTION X: PHOTOCHEMICAL, PHOTOTHERMAL, AND PHOTOMECHANICAL, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser-Tissue Interaction X - Photochemical, Photothermal, and Photomechanical CY JAN 24-27, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE aspherical dynamics; bubble dynamics; bubble energy; bubble oscillation period; cavitation; cylindrical dynamics; hydrodynamics; laser-medical applications; numerical methods ID LASER-INDUCED BREAKDOWN; CAVITATION BUBBLES; PULSE DURATION; THROMBOLYSIS; ABLATION; BOUNDARY; WATER AB Novel features of aspherical bubble dynamics are explored. Time-resolved experimental photographs and simulations of large aspect ratio (length:diameter similar to 20) cylindrical bubble dynamics are presented. The experiments and calculations exhibit similar dynamics. A small high-pressure cylindrical bubble initially expands radially with hardly any axial motion. Then, after reaching its maximum volume, a cylindrical bubble collapses along its long axis with relatively little radial motion. The growth-collapse period of these very aspherical bubbles differs only slightly from twice the Rayleigh collapse time for a spherical bubble with an equivalent maximum volume. This fact justifies using the temporal interval between the acoustic signals emitted upon bubble creation and collapse to estimate the maximum bubble volume. As a result, hydrophone measurements can provide an estimate of the bubble energy even for aspherical bubbles. The prolongation of the oscillation period of bubbles near solid boundaries relative to that of isolated spherical bubbles is also discussed. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Godwin, RP (reprint author), Univ Calif Los Alamos Natl Lab, MS F664, Los Alamos, NM 87545 USA. NR 23 TC 13 Z9 13 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3071-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3601 BP 225 EP 236 DI 10.1117/12.350042 PG 12 WC Engineering, Biomedical; Immunology; Medicine, Research & Experimental; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Immunology; Research & Experimental Medicine; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BN29E UT WOS:000081436500027 ER PT S AU Kim, BM Gentile, NA Trauner, KB London, RA AF Kim, BM Gentile, NA Trauner, KB London, RA BE Jacques, SL Muller, GJ Roggan, A Sliney, DH TI Three dimensional Monte-Carlo modeling of laser-tissue interaction SO LASER-TISSUE INTERACTION X: PHOTOCHEMICAL, PHOTOTHERMAL, AND PHOTOMECHANICAL, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser-Tissue Interaction X - Photochemical, Photothermal, and Photomechanical CY JAN 24-27, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc AB A full three dimensional Monte-Carlo program was developed for analysis of the laser-tissue interactions. This project was performed as a part of the LATIS3D (3-D Laser-TISsue interaction) project. The accuracy was verified against results from a public domain two dimensional axisymmetric program. The code was used for simulation of light transport in simplified human knee geometry. Using the real human knee meshes which will be extracted from MRI images in the near future, a full analysis of dosimetry and surgical strategies for photodynamic therapy of rheumatoid arthritis will be followed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Kim, BM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 4 TC 0 Z9 0 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3071-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3601 BP 320 EP 326 DI 10.1117/12.350015 PG 7 WC Engineering, Biomedical; Immunology; Medicine, Research & Experimental; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Immunology; Research & Experimental Medicine; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BN29E UT WOS:000081436500037 ER PT S AU Everett, MJ Colston, BW Sathyam, US Da Silva, LB Fried, D Featherstone, JDB AF Everett, MJ Colston, BW Sathyam, US Da Silva, LB Fried, D Featherstone, JDB BE Featherstone, JDB Rechmann, P Fried, D TI Non-invasive diagnosis of early caries with polarization sensitive optical coherence tomography (PS-OCT) SO LASERS IN DENTISTRY V, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Lasers in Dentistry V CY JAN 24-25, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE interferometry; polarization; birefringence; caries; biological tissue ID UNITED-STATES; BIREFRINGENCE CHARACTERIZATION; BIOLOGICAL TISSUE; DENTITION; ADULTS AB There is no diagnostic technology presently available utilizing non-ionizing radiation that can image the state of demineralization of dental enamel in vivo for the detection, characterization and monitoring of early, incipient caries lesions. in this study, a Polarization Sensitive Optical Coherence Tomography (PS-OCT) system was evaluated for its potential for the non-invasive diagnosis of early carious lesions. We demonstrated clear discrimination in PS-OCT images between regions of normal and demineralized enamel in bovine enamel blocks containing well-characterized artificial lesions. Moreover, high-resolution, cross-sectional images were acquired that clearly discriminate between the normal and carious regions of extracted human teeth. Regions that appeared to be demineralized in the PS-OCT images were verified using histological thin sections examined under polarized light. The PS-OCT system discriminates between normal and carious regions by measuring the state of polarization of the back-scattered 1310 nm light, which is affected by the state of demineralization of the enamel. The demineralized regions of enamel have a large scattering coefficient, thus depolarizing the incident light. This initial study shows that PS-OCT has great potential for the detection, characterization, and monitoring of incipient caries lesions. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Everett, MJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 8 TC 41 Z9 41 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3063-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3593 BP 177 EP 182 DI 10.1117/12.348347 PG 6 WC Dentistry, Oral Surgery & Medicine; Optics SC Dentistry, Oral Surgery & Medicine; Optics GA BN13T UT WOS:000080848900029 ER PT S AU Chapyak, EJ Godwin, RP AF Chapyak, EJ Godwin, RP BE Anderson, RR Bartels, KE Bass, LS Bornhop, DJ Garrett, CG Gregory, KW Kollias, N Lui, H Malek, RS Perlmutter, AP Reidenbach, HD Reinisch, L Robinson, DS Tate, LP Trowers, EA TI Simulations of laser thrombolysis SO LASERS IN SURGERY: ADVANCED CHARACTERIZATION, THERAPEUTICS, AND SYSTEMS IX, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Lasers in Surgery - Advanced Characterization, Therapeutic, and Systems IX CY JAN 23-24, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE bubble dynamics; cavitation; confinement; jet formation; hydrodynamics; laser thrombolysis; material properties; numerical methods; tissue properties; wall effects ID DYNAMICS AB We have shown that bubble expansion and collapse near the interface between two materials with modest property differences produces jet-like interpenetration of the two materials. The bubble dynamics at a water-viscous fluid interface is compared with that at the interface of water with a weak elastic-plastic material. We find that, despite rather similar behavior during bubble growth and the initial portion of bubble collapse, the terminal jetting behavior is quite different, even in direction. The elastic-plastic properties chosen are representative of real and surrogate thrombus. Simulations using the elastic-plastic model agree quantitatively with laboratory thrombolysis mass-removal experiments. In out earlier simulations of laboratory experiments, walls have been remote so as to not affect the dynamics. Here we present two-dimensional simulations of thrombolysis with water over elastic-plastic surrogate thrombus in a geometry representative of the clinical situation. The calculations include thin cylindrical elastic walls with properties and dimensions appropriate for arteries. The presence of these artery walls does not substantially change the interface jetting predicted in unconfined simulations. C1 Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. RP Chapyak, EJ (reprint author), Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, MS F664, Los Alamos, NM 87545 USA. NR 17 TC 3 Z9 3 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3060-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3590 BP 328 EP 335 DI 10.1117/12.350979 PG 8 WC Cardiac & Cardiovascular Systems; Dermatology; Gastroenterology & Hepatology; Optics; Otorhinolaryngology; Surgery; Urology & Nephrology; Veterinary Sciences SC Cardiovascular System & Cardiology; Dermatology; Gastroenterology & Hepatology; Optics; Otorhinolaryngology; Surgery; Urology & Nephrology; Veterinary Sciences GA BN29C UT WOS:000081436000041 ER PT B AU Garvey, GT AF Garvey, GT CA LSND Collaboration BE KlapdorKleingrothaus, HV Krivosheina, IV TI Searches for neutrino oscillations: LSND SO LEPTON AND BARYON NUMBER VIOLATION IN PARTICLE PHYSICS, ASTROPHYSICS AND COSMOLOGY LA English DT Proceedings Paper CT 1st International Conference on Lepton and Baryon Number Violation (Lepton-Baryon 98) CY APR 20-25, 1998 CL EUROPEAN CTR THEORET STUDIES NUCLEAR PHYS & RELATED AREAS, TRENTE, ITALY HO EUROPEAN CTR THEORET STUDIES NUCLEAR PHYS & RELATED AREAS ID (NU)OVER-BAR(MU)->(NU)OVER-BAR(E) OSCILLATIONS; FACILITY; DETECTOR; PHYSICS; BEAM; ISIS AB The LSND experiment at Los Alamos has conducted searches for <(nu)over bar>(mu) --> <(nu)over bar>(e) oscillations using <(nu)over bar>(mu) from mu(+) decay at rest and for nu(mu) --> nu(e) oscillations using nu(mu) from pi(+) decay in flight. For the <(nu)over bar>(mu) --> <(nu)over bar>(e) search, a total excess of 82.8 +/- 23.7 +/- 12.0 events is observed with e(+) energy between 20 and 60 MeV, while for the nu(mu) --> nu(e) search, a total excess of 18.1 +/- 6.6 +/- 4.0 events is observed with e(-) energy between 60 and 200 MeV. If attributed to neutrino oscillations, these excesses correspond to oscillation probabilities (averaged over the experimental energies and spatial acceptances) of (0.31 +/- 0.09 +/- 0.05)% and (0.26 +/- 0.10 +/- 0.05)%, respectively. For the future, the BooNE experiment at Fermilab could conclusively prove that neutrino oscillations occur and make precision measurements of Delta m(2) and sin(2) 2 theta. C1 Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. RP Garvey, GT (reprint author), Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND BN 0-7503-0616-5 PY 1999 BP 227 EP 250 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN69U UT WOS:000082635300011 ER PT S AU Yang, TC George, KA Wu, H Miller, D Miller, J AF Yang, TC George, KA Wu, H Miller, D Miller, J BE Yang, TC TI Cytogenetic effects of energetic ions with shielding SO LIFE SCIENCES: BIODOSIMETRY, CHROMOSOME DAMAGE AND CARCINOGENESIS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT F2 4 Symposium of COSPAR Scientific Commission F, at the 32nd COSPAR Scientific Assembly on Life Sciences - Biodosimetry, Chromosome Damage and Carcinogenesis CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP COSPAR Scientif Commiss F, NASA, European Space Agcy, Natl Space Dev Agcy Japan, Russian Space Agcy AB In order to understand the effects of shielding on the induction of biological damages by charged particles, we conducted experiments with accelerated protons (250 MeV) and iron particles (I GeV/u). Human lymphocytes in vitro were exposed to particle beams through polyethylene with various thickness, and chromosomal aberrations were determined using FISH technique. Dose response curves for chromosome aberrations were obtained and compared for various particle types. Experimental results indicated that for a given absorbed dose at the cell, the effectiveness of protons and iron particles in the induction of chromosomal aberrations was not significantly altered by polyethylene with thickness up to 30-cm and 15-cm respectively. Comparing with gamma rays, charged particles were very effective in producing complex chromosomal damages, which may be an important mechanism in alterating functions in nondividing tissues, such as nervous systems. (C) 1999 COSPAR. Published by Elsevier Science Ltd. C1 NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Houston, TX 77058 USA. Wyle Labs, Houston, TX 77058 USA. Kelsey Seybold Clin, Houston, TX 77058 USA. Loma Linda Univ, Med Ctr, Loma Linda, CA 92350 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Yang, TC (reprint author), NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Houston, TX 77058 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 BN 0-08-043640-4 J9 ADV SPACE RES PY 1999 VL 22 IS 12 BP 1683 EP 1690 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Biology; Genetics & Heredity; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Genetics & Heredity; Geology; Meteorology & Atmospheric Sciences GA BM91D UT WOS:000080096200006 ER PT S AU Jones, ED Modine, NA Allerman, AA Fritz, IJ Kurtz, SR Wright, AF Tozer, ST Wei, X AF Jones, ED Modine, NA Allerman, AA Fritz, IJ Kurtz, SR Wright, AF Tozer, ST Wei, X BE Schubert, EF Ferguson, IT Yao, HW TI Optical properties of InGaAsN: A new 1eV bandgap material system SO LIGHT-EMITTING DIODES: RESEARCH, MANUFACTURING, AND APPLICATIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 3rd Conference on Light-Emitting Diodes CY JAN 27-28, 1999 CL SAN JOSE, CA SP SPIE, Defense Adv Res Project Agcy DE InGaAsN; band structure; LDA; photoluminescence; pressure dependent energy gaps; conduction-band mass ID WAVELENGTH SEMICONDUCTOR-LASERS; TOTAL-ENERGY CALCULATIONS; QUANTUM-WELL STRUCTURES; WAVE BASIS-SET; MOLECULAR-DYNAMICS; MAGNETIC-FIELD; GAASN ALLOYS; GAINNAS; GAP; LUMINESCENCE AB InGaAsN is a new semiconductor alloy system with the remarkable property that the inclusion of only 2% nitrogen reduces the bandgap by more than 30%. In order to help understand the physical origin of this extreme deviation from the typically observed nearly linear dependence of alloy properties on concentration, we have investigated the pressure dependence of the excited state energies using both experimental and theoretical methods. We report measurements of the low temperature photoluminescence energy of the material for pressures between ambient and 110 kbar. We describe a simple, density-functional-theory-based approach to calculating the pressure dependence of low lying excitation energies for low concentration alloys. The theoretically predicted pressure dependence of the bandgap is in excellent agreement with the experimental data. Based on the results of our calculations, we suggest an explanation for the strongly non-linear pressure dependence of the bandgap that, surprisingly, does not involve a nitrogen impurity band. Additionally, conduction-band mass measurements, measured by three different techniques, will be described and finally, the magnetoluminescence determined pressure coefficient for the conduction-band mass is measured. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Jones, ED (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 35 TC 35 Z9 35 U1 1 U2 6 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3091-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3621 BP 52 EP 63 DI 10.1117/12.344488 PG 12 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BN06C UT WOS:000080521600006 ER PT B AU Hryn, JN Pellin, MJ AF Hryn, JN Pellin, MJ BE Eckert, CE TI A dynamic inert metal anode SO LIGHT METALS 1999 LA English DT Proceedings Paper CT 128th TMS Annual Meeting CY FEB 28-MAR 04, 1999 CL SAN DIEGO, CA SP Min, Met & Mat Soc ID CONDUCTIVITY COPPER-FILMS; SURFACE; OXIDATION; CORROSION; AL; PASSIVATION; DIFFUSION AB A new concept for a stable anode for aluminum electrowinning is described. The anode consists of a cup-shaped metal alloy container filled with a molten salt that contains dissolved aluminum. The metal alloy can be any of a number of alloys, but it must contain aluminum as a secondary alloying metal. A possible alloy composition is copper with 5 to 15 weight percent aluminum. In the presence of oxygen, aluminum on the metal anode's exterior surface forms a continuous alumina film that is thick enough to protect the anode from chemical attack by cryolite during electrolysis and thin enough to maintain electrical conductivity. However, the alumina film is soluble in cryolite, so it must be regenerated in situ. Film regeneration is achieved by the transport of aluminum metal from the anode's molten salt interior through the metal wall to the anode's exterior surface, where the transported aluminum oxidizes to alumina in the presence of evolving oxygen to maintain the protective alumina film. Periodic addition of aluminum metal to the anode's interior keeps the aluminum activity in the molten salt at the desired lever. This concept for an inert anode is viable as long as the amount of aluminum produced at the cathode greatly exceeds the amount of aluminum required to maintain the anode's protective film. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Hryn, JN (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Pellin, Michael/B-5897-2008 OI Pellin, Michael/0000-0002-8149-9768 NR 36 TC 13 Z9 20 U1 1 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-425-9 PY 1999 BP 377 EP 381 PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM93W UT WOS:000080192500055 ER PT B AU Taleyarkhan, RP Kim, SH AF Taleyarkhan, RP Kim, SH BE Eckert, CE TI Fundamental studies on molten aluminum-water explosion prevention in direct-chill casting pits SO LIGHT METALS 1999 LA English DT Proceedings Paper CT 128th TMS Annual Meeting CY FEB 28-MAR 04, 1999 CL SAN DIEGO, CA SP Min, Met & Mat Soc AB Explosive interactions between molten aluminum and water have been studied with a focus on fundamentals to determine what causes robust-enough triggers for explosion onset, as well as to determine the extent of protection provided from various coatings, and to develop a novel methodology for prevention. The steam explosion triggering studies (SETS) facility was designed and constructed as a rapid-turnaround, cost-effective, and safe means to address these phenomenological issues and to derive quantitative, "practically-fundamental" data for situations covering melt masses relocating over submerged surfaces ranging up to similar to 1000 kg (2,000 Ib.). Test data obtained from the SETS facility correlated extremely well with past industry data. Explosion onset was determined to result from a combination of factors related to wettability, degree of wearoff, bare spots, charring, existence of bypass relief pathways and non-condensible gases (NCGs). Of these, NCG generation or injection was found to be the most important and overwhelming leading to development of a potentially-novel methodology for cost-effective, environmentally benign and conclusive explosion prevention. Significant data was also obtained on coating durability, as well as on relevance of external shocks, impact of bare spots, and impact of increased melt mass on explosion intensity. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Taleyarkhan, RP (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-425-9 PY 1999 BP 911 EP 916 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM93W UT WOS:000080192500133 ER PT B AU Gourishankar, KV Karell, EJ AF Gourishankar, KV Karell, EJ BE Eckert, CE TI Application of lithium in molten-salt reduction processes SO LIGHT METALS 1999 LA English DT Proceedings Paper CT 128th TMS Annual Meeting CY FEB 28-MAR 04, 1999 CL SAN DIEGO, CA SP Min, Met & Mat Soc AB Metallothermic reductions have been extensively studied in the field of extractive metallurgy. At Argonne National Laboratory (ANL), we have developed a molten-salt based reduction process using lithium. This process was originally developed to reduce actinide oxides present in spent nuclear fuel. Preliminary thermodynamic considerations indicate that this process has the potential to be adapted for the extraction of other metals. The reduction is carried out at 650 degrees C in a molten-salt (LiCl) medium. Lithium oxide (Li2O), produced during the reduction of the actinide oxides, dissolves in the molten salt. At the end of the reduction step, the lithium is regenerated from the salt by an electrowinning process. The lithium and the salt from the electrowinning are then reused for reduction of the next batch of oxide fuel. The process cycle has been successfully demonstrated on an engineering scale in a specially designed pyroprocessing facility. This paper discusses the applicability of lithium in molten-salt reduction processes with specific reference to our process. Results are presented from our work on actinide oxides to highlight the role of lithium and its effect on process variables in these molten-salt based reduction processes. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Gourishankar, KV (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 6 Z9 6 U1 0 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-425-9 PY 1999 BP 1123 EP 1128 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM93W UT WOS:000080192500161 ER PT B AU McDeavitt, SM AF McDeavitt, SM BE Eckert, CE TI Synthesis and casting of a lithium-bismuth compound for an ion-replacement electrorefiner SO LIGHT METALS 1999 LA English DT Proceedings Paper CT 128th TMS Annual Meeting CY FEB 28-MAR 04, 1999 CL SAN DIEGO, CA SP Min, Met & Mat Soc ID SPENT NUCLEAR-FUEL AB The intermetallic compound Li3Bi played an integral part in the demonstration of an ion replacement electrorefining method developed at Argonne National Laboratory. The Li3Bi compound was generated in a tilt-pour casting furnace using high-purity lithium and bismuth metals as the initial charge. At first, small-scale (similar to 20 g) experiments were conducted to determine the materials synthesis parameters. In the end, four larger-scale castings (500 g to 1250 g) were completed in a tantalum crucible. The metals were heated slowly to melt the charge, and the formation reaction proceeded vigorously above the melting point of bismuth (similar to 270 degrees C). For the large-scale melts, the furnace power was temporarily turned off at this point. After several minutes, the tantalum crucible stopped glowing, and the furnace power was turned on. The temperature was then increased to similar to 1200 degrees C to melt and homogenize the compound, and liquid Li,Bi was cast into cold stainless steel molds. Approximately 3.7 kg of Li3Bi was generated by this method. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP McDeavitt, SM (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-425-9 PY 1999 BP 1139 EP 1142 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM93W UT WOS:000080192500165 ER PT J AU Mulholland, PJ Marzolf, ER Webster, JR Hart, DR Hendricks, SP AF Mulholland, PJ Marzolf, ER Webster, JR Hart, DR Hendricks, SP TI Evidence that hyporheic zones increase heterotrophic metabolism and phosphorus uptake in forest streams (vol 42, pg 443, 1997) SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Correction C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. St Johns River Water Management Dist, Palatka, FL 32178 USA. Virginia Tech, Dept Biol, Blacksburg, VA 24061 USA. Tel Aviv Univ, Dept Zool, IL-69978 Tel Aviv, Israel. Hancock Biol Stn, Murray, KY 42071 USA. RP Mulholland, PJ (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Mulholland, Patrick/C-3142-2012 NR 4 TC 2 Z9 2 U1 0 U2 9 PU AMER SOC LIMNOLOGY OCEANOGRAPHY PI WACO PA 5400 BOSQUE BLVD, STE 680, WACO, TX 76710-4446 USA SN 0024-3590 J9 LIMNOL OCEANOGR JI Limnol. Oceanogr. PD JAN PY 1999 VL 44 IS 1 BP 230 EP 231 PG 2 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 162ZT UT WOS:000078378300022 ER PT S AU Ferris, KF Exarhos, GJ Risser, SM AF Ferris, KF Exarhos, GJ Risser, SM BE Bunning, TJ Chen, SH Chien, LC Kajiyama, T Koide, N Lien, SCA TI Relation between molecular and macroscopic properties of nematic liquid crystals SO LIQUID CRYSTAL MATERIALS AND DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Liquid Crystal Materials and Devices, at the 1999 MRS Spring Meeting CY APR 05-07, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Air Force Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, Everlight Chem Ind Corp, European Off Aerosp Res & Dev ID INTERNAL-ROTATION; BIPHENYL; OPTIMIZATION; PLANAR AB While many liquid crystal studies have focused on static structural and electronic properties, dynamic factors such as molecular anisotropy, partial ordering and structural fluctuations have hindered descriptions linking liquid crystalline properties at the molecular level with the macroscopic level properties (as measured experimentally). In this paper, we examine the transition from molecular to bulk properties for the nematogen 5-alkyl-cyanobiphenyl (5CB), using both molecular dynamics and quantum mechanical calculations. We perform molecular dynamics simulations on a collection of molecules in the nematic phase, sample the trajectory to create a representative collection of structures, and perform electronic structure calculations on the sampled structures. C1 Pacific NW Natl Labs, Richland, WA 99352 USA. RP Ferris, KF (reprint author), Pacific NW Natl Labs, Richland, WA 99352 USA. NR 17 TC 2 Z9 2 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-466-1 J9 MATER RES SOC SYMP P PY 1999 VL 559 BP 257 EP 262 PG 6 WC Crystallography; Materials Science, Multidisciplinary SC Crystallography; Materials Science GA BN69C UT WOS:000082590700034 ER PT S AU Wiederrecht, GP Svec, WA Niemczyk, MP Wasielewski, MR AF Wiederrecht, GP Svec, WA Niemczyk, MP Wasielewski, MR BE Khoo, IC TI Photorefractivity in liquid crystals doped with a soluble conjugated polymer SO LIQUID CRYSTALS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Liquid Crystals III CY JUL 21-22, 1999 CL DENVER, CO SP SPIE DE liquid crystals; photorefractive materials; photoconductive polymers ID ACCEPTOR MOLECULES; ELECTRON-DONOR; CHARGE SEPARATION; DIFFRACTION; GAIN AB Photoconductive polymers are doped into liquid crystals to create a new mechanism for space-charge field formation in photorefractive liquid crystal composites. The composites contain poly(2,5-bis(2'-ethylhexyloxy)-1,4-phenylenevinylene) (BEH-PPV) and the electron acceptor N,N'-dioctyl-1,4:5,8-naphthalenediimide, NI. Using asymmetric energy transfer (beam coupling) measurements that are diagnostic for the photorefractive effect, the direction of beam coupling as a function of grating fringe spacing inverts at a spacing of 5.5 mu m. We show that the inversion is due to a change in the dominant mechanism for space-charge field formation. At small fringe spacings, the space-charge field is formed by ion diffusion in which the photogenerated anion is the more mobile species. At larger fringe spacings, the polarity of the space charge field inverts due to dominance of a charge transport mechanism in which photogenerated holes are the most mobile species due to hole migration along the BEH-PPV chains coupled with interchain hole hopping. Control experiments are presented, which use composites that can access only one of the two charge transport mechanisms. The results show that charge migration over long distances leading to enhanced photorefractive effects can be obtained using conjugated polymers dissolved in liquid crystals. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Wiederrecht, GP (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 33 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3286-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3800 BP 13 EP 20 DI 10.1117/12.365799 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BN98W UT WOS:000083764900002 ER PT B AU Abraham, DP Richardson, JW AF Abraham, DP Richardson, JW BE Fuchs, GE Dannemann, KA Deragon, TC TI Phase stability of laves intermetallics in a stainless steel-zirconium alloy SO LONG TERM STABILITY OF HIGH TEMPERATURE MATERIALS LA English DT Proceedings Paper CT Symposium on Long Term Stability of High Temperature Materials at the 1999 TMS Annual Meeting CY FEB 28-MAR 04, 1999 CL SAN DIEGO, CA SP TMS ID WASTE FORMS AB Phase transformations occurring in a stainless steel-15 wt% zirconium (SS-15Zr) alloy were studied by insitu neutron diffraction. Neutron diffraction patterns as a function of time were obtained on alloys that were held at various elevated temperatures (1084-1275 degrees C). As-cast SS-15Zr alloys contain ferrite, austenite, ZrFe2-type Laves polytypes C36 and C15, and small amounts of a Fe23Zr6-type intermetallic. Annealing at high temperatures resulted in an increase of the Fe23Zr6 intermetallic content. The C15 Laves polytype is the equilibrium phase for T less than or equal to 1230 degrees C; C36 is the stable polytype at higher temperatures (similar to 1275 degrees C). Phase changes were slow for temperatures <1100 degrees C. These findings have important implications for use of the SS-15Zr alloy as a nuclear waste form. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60490 USA. RP Abraham, DP (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60490 USA. NR 7 TC 6 Z9 6 U1 0 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-453-4 PY 1999 BP 169 EP 179 PG 11 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BP03V UT WOS:000083949800012 ER PT B AU van Breugel, W De Breuck, C Rottgering, H Miley, G Stanford, A AF van Breugel, W De Breuck, C Rottgering, H Miley, G Stanford, A BE Morganti, R Couch, WJ TI Very high redshift radio galaxies SO LOOKING DEEP IN THE SOUTHERN SKY SE ESO ASTROPHYSICS SYMPOSIA LA English DT Proceedings Paper CT ESO/Australia Workshop on Looking Deep in the Southern Sky CY DEC 10-12, 1997 CL STATE LIB NEW S WALES, SYDNEY, AUSTRALIA SP Australian Govt, Dept Ind Sci & Tourism, European So Observ, Australia Telescope Natl Facil, Anglo Australian Observ, Syndey Univ, Special Res Ctr Theoret Astrophys, Mt Stromlo & Siding Spring Observ HO STATE LIB NEW S WALES ID SKY SURVEY; Z=3.8; MHZ AB High redshift radio galaxies (HzRGs) provide unique targets for the study of the formation and evolution of massive galaxies and galaxy clusters at very high redshifts. We discuss how efficient HzRG samples are selected, the evidence for strong morphological evolution at near-infrared wavelengths, and for jet-induced star formation in the z = 3.800 HzRG 4C41.17. C1 Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. RP van Breugel, W (reprint author), Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, L-413,POB 808, Livermore, CA 94550 USA. NR 28 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-65286-8 J9 ESO ASTROPHY SYMP PY 1999 BP 236 EP 245 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP54Y UT WOS:000085467500043 ER PT B AU De Breuck, C van Breugel, W Rottgering, H Miley, G Carilli, C AF De Breuck, C van Breugel, W Rottgering, H Miley, G Carilli, C BE Morganti, R Couch, WJ TI The highest redshift radio galaxy known in the southern hemisphere SO LOOKING DEEP IN THE SOUTHERN SKY SE ESO ASTROPHYSICS SYMPOSIA LA English DT Proceedings Paper CT ESO/Australia Workshop on Looking Deep in the Southern Sky CY DEC 10-12, 1997 CL STATE LIB NEW S WALES, SYDNEY, AUSTRALIA SP Australian Govt, Dept Ind Sci & Tourism, European So Observ, Australia Telescope Natl Facil, Anglo Australian Observ, Syndey Univ, Special Res Ctr Theoret Astrophys, Mt Stromlo & Siding Spring Observ HO STATE LIB NEW S WALES ID MHZ AB We present the discovery of a z = 4.13 galaxy TN J1338-1942, the most distant radio galaxy in the southern hemisphere known to date. The source was selected from a sample of Ultra Steep Spectrum (USS; alpha < -1.3; S proportional to nu(alpha)) radio sources using the Texas and NVSS catalogs. The discovery spectrum, obtained with the ESO 3.6m telescope, shows bright extended Ly-alpha emission. The radio source has a very asymmetric morphology, suggesting a strong interaction with an inhomogeneous surrounding medium. C1 Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. RP De Breuck, C (reprint author), Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, L-413,POB 808, Livermore, CA 94550 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-65286-8 J9 ESO ASTROPHY SYMP PY 1999 BP 246 EP 247 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP54Y UT WOS:000085467500044 ER PT S AU Lee, YE Rouleau, CM Park, C Norton, DP AF Lee, YE Rouleau, CM Park, C Norton, DP BE McKittrick, J DiBartolo, B Mishra, K TI ZnGa2O4 thin-film phosphors grown by pulsed laser ablation SO LUMINESCENT MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium E on Luminescent Materials at the 1999 MRS Spring Meeting CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc ID PHOTOLUMINESCENCE; EMISSION; OXIDE AB The growth and properties of undoped and Mn-doped ZnGa2O4, thin-film phosphors on (100) MgO and glass substrates using pulsed laser ablation were investigated. Blue-white and green emission were observed for as-deposited undoped and Mn-doped films, respectively. Luminescent properties as well as crystallinity were considerably affected by processing conditions and film stoichiometry. Films with enhanced luminescent characteristics were obtained on single crystal substrates without post-annealing. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Lee, YE (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Rouleau, Christopher/Q-2737-2015 OI Rouleau, Christopher/0000-0002-5488-3537 NR 12 TC 0 Z9 0 U1 2 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-467-X J9 MATER RES SOC SYMP P PY 1999 VL 560 BP 59 EP 64 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Materials Science GA BN84R UT WOS:000083174400009 ER PT S AU Shea, LE Walko, RJ AF Shea, LE Walko, RJ BE McKittrick, J DiBartolo, B Mishra, K TI Performing accurate cathodoluminescence measurements of phosphor powders and screens SO LUMINESCENT MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium E on Luminescent Materials at the 1999 MRS Spring Meeting CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc AB Tn the field of display phosphors, the efficiency of the cathodoluminescence process is a characteristic that is often used to assess the potential of a phosphor for use in flat-panel display applications such as field emission displays (FEDs). Cathodoluminescence characterization in a demountable vacuum chamber is important for preliminary evaluation and lifetesting of phosphor powders and screens prior to incorporation into an actual display device. There are many experimental factors that influence accurate measurement and calculation of the cathodoluminescence efficiency. These include electron beam profile (uniform, Gaussian), current density, electron accelerating voltage, secondary electron collection, and optical detection system. This paper will present some methods for achieving improved accuracy of cathodoluminescence measurements in systems at Sandia National Laboratories, using Y2O3:Eu as a representative phosphor. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Shea, LE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-467-X J9 MATER RES SOC SYMP P PY 1999 VL 560 BP 127 EP 132 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Materials Science GA BN84R UT WOS:000083174400020 ER PT S AU Goddard, JS Sari-Sarraf, H Turner, JC Hunt, MA Abidi, BR AF Goddard, JS Sari-Sarraf, H Turner, JC Hunt, MA Abidi, BR BE Tobin, KW Chang, NS TI Depth measurement of moving slurry at the wet end of a paper machine SO MACHINE VISION APPLICATIONS IN INDUSTRIAL INSPECTION VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Machine Vision Applications in Industrial Inspection VII CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Soc Imaging Sci & Technol DE paper; inspection; laser; profilometry; CMOS; range imaging AB The paper industry has long had a need to better understand and control its papermaking process upstream, specifically at the wet end in the forming section of a paper machine. A vision-based system is under development that addresses this need by automatically measuring and interpreting the pertinent paper web parameters at the wet end in real time. The wet-end characterization of the paper web by a vision system involves a four-dimensional measurement of the slurry in real time. These measurements include the two-dimensional spatial information, the intensity profile, and the depth profile. This paper describes the real-time depth profile measurement system for the high-speed moving slurry. A laser line-based measurement method is used with a high speed programmable camera to directly measure slurry height. The camera is programmed with a profile algorithm, producing depth data at fast sampling rates. Analysis and experimentation have been conducted to optimize the system for the characteristics of the slurry and laser line image. On-line experimental results are presented. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Goddard, JS (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3123-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3652 BP 21 EP 27 PG 7 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Optics SC Automation & Control Systems; Computer Science; Optics GA BM86Z UT WOS:000079968700003 ER PT S AU Hunt, MA Goddard, JS Hylton, KW Karnowski, TP Richards, RK Simpson, ML Tobin, KW Treece, DA AF Hunt, MA Goddard, JS Hylton, KW Karnowski, TP Richards, RK Simpson, ML Tobin, KW Treece, DA BE Tobin, KW Chang, NS TI Imaging tristimulus colorimeter for the evaluation of color in printed textiles SO MACHINE VISION APPLICATIONS IN INDUSTRIAL INSPECTION VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Machine Vision Applications in Industrial Inspection VII CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Soc Imaging Sci & Technol DE imaging colorimeter; tristimulus response; projection on convex sets; segmentation; printed pattern inspection ID SEGMENTATION AB The high-speed production of textiles with complicated printed patterns presents a difficult problem for a colormetric measurement system. Accurate assessment of product quality requires a repeatable measurement using a standard color space, such as CIELAB, and the use of a perceptually based color difference formula, e.g Delta E-CMC color difference formula. Image based:color sensors used for on-line measurement are not colormetric by nature and require a non-linear transformation of the component colors based on the spectral properties of the incident illumination, imaging sensor, and the actual textile color. This research and development effort describes a benchtop, proof-of-principle system that implements a projection onto convex sets (POCS) algorithm for mapping component color measurements to standard tristimulus values and incorporates structural and color based segmentation for improved precision and accuracy. The POCS algorithm consists of determining the closed convex sets that describe the constraints on the reconstruction of the true tristimulus values based on the measured imperfect values. We show that using a simulated D65 standard illuminant, commercial filters and a CCD camera, accurate (under perceptibility limits) per-region based Delta E-CMC values can be measured on real textile samples. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hunt, MA (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 18 TC 0 Z9 0 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3123-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3652 BP 118 EP 128 DI 10.1117/12.341131 PG 11 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Optics SC Automation & Control Systems; Computer Science; Optics GA BM86Z UT WOS:000079968700015 ER PT S AU Tobin, KW Karnowski, TP Ferrell, RK AF Tobin, KW Karnowski, TP Ferrell, RK BE Tobin, KW Chang, NS TI Image retrieval in the industrial environment SO MACHINE VISION APPLICATIONS IN INDUSTRIAL INSPECTION VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Machine Vision Applications in Industrial Inspection VII CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Soc Imaging Sci & Technol DE content-based image retrieval; manufacturing environment; semiconductor yield management; hierarchical pattern recognition; similarity measures ID CLASSIFICATION AB The ability to manage large image databases has been a topic of growing research over the past several years. Imagery is being generated and maintained for a large variety of applications including remote sensing, art galleries, architectural and engineering design, geographic information systems, weather forecasting, medical diagnostics, and law enforcement. Content-based image retrieval (CBIR) represents a promising and cutting-edge technology that is being developed to address these needs. To date, little work has been accomplished to apply these technologies to the manufacturing environment. Imagery collected from manufacturing processes have unique characteristics that can be used in developing a manufacturing-specific CBIR approach, For example, a product image typically has an expected structure that can be characterized in terms of its redundancy, texture, geometry, or a mixture of these. Defect objects in product imagery share a number of common traits across product types and imaging modalities as well. For example, defects tend to be contiguous, randomly textured, irregularly shaped, and they disrupt the background and the expected pattern. We will present the initial results of the development of a new capability for manufacturing-specific CBIR that addresses defect analysis, product quality control, and process understanding in the manufacturing environment. Image data from the semiconductor-manufacturing environment will be presented. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Tobin, KW (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Escarabajal, Juan Antonio/C-5644-2012 NR 21 TC 4 Z9 4 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3123-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3652 BP 184 EP 192 PG 9 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Optics SC Automation & Control Systems; Computer Science; Optics GA BM86Z UT WOS:000079968700021 ER PT J AU Fukui, K Sumpter, BG Barnes, MD Noid, DW Otaigbe, JU AF Fukui, K Sumpter, BG Barnes, MD Noid, DW Otaigbe, JU TI Molecular dynamics simulation of the thermal properties of nanoscale polymer particles SO MACROMOLECULAR THEORY AND SIMULATIONS LA English DT Article ID POLYETHYLENE AB Molecular dynamics simulations for nanometer scale polyethylene (PE) particles generated with up to 12000 atoms are presented to gain insight into some thermodynamic properties of ultrafine polymer powders. By computing molecular volume and total energy as a function of temperature, we obtained melting point, glass transition temperature, and heat capacity. The results of our simulations predict an interesting reduction of the melting point in comparison with the PE bulk system. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Iowa State Univ, Dept Chem Engn, Ames, IA 50011 USA. RP Fukui, K (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. EM fukuih@ornl.gov RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 25 TC 20 Z9 20 U1 0 U2 4 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1022-1344 J9 MACROMOL THEOR SIMUL JI Macromol. Theory Simul. PD JAN PY 1999 VL 8 IS 1 BP 38 EP 45 DI 10.1002/(SICI)1521-3919(19990101)8:1<38::AID-MATS38>3.0.CO;2-B PG 8 WC Polymer Science SC Polymer Science GA 159WR UT WOS:000078198800006 ER PT B AU Goodson, BM Kaiser, L Pines, A AF Goodson, BM Kaiser, L Pines, A BE Maraviglia, B TI NMR and MRI of laser-polarized noble gases in molecules, materials, and medicine SO MAGNETIC RESONANCE AND BRAIN FUNCTION: APPROACHES FROM PHYSICS SE PROCEEDINGS OF THE INTERNATIONAL SCHOOL OF PHYSICS ENRICO FERMI LA English DT Proceedings Paper CT International School of Physics Enrico Fermi on Magnetic Resonance and Brain Function: Approaches from Physics CY JUN 23-JUL 03, 1998 CL VARENNA LAKE COMO, ITALY SP Int Sch Phys Enrico Fermi ID NUCLEAR-MAGNETIC-RESONANCE; HYPERPOLARIZED XE-129; CROSS-POLARIZATION; ALPHA-CYCLODEXTRIN; SOLID-STATE; ADSORBED XENON; CRYPTOPHANE-A; SPIN-EXCHANGE; ENHANCED NMR; LIQUID XENON C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Goodson, BM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 118 TC 3 Z9 3 U1 1 U2 3 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS BN 90-5199-501-6 J9 P INT SCH PHYS PY 1999 VL 139 BP 211 EP 260 PG 50 WC Physics, Applied; Radiology, Nuclear Medicine & Medical Imaging SC Physics; Radiology, Nuclear Medicine & Medical Imaging GA BP87P UT WOS:000086455800005 ER PT B AU Budinger, TF Budinger, MD AF Budinger, TF Budinger, MD BE Maraviglia, B TI Physiological changes in brain microcirculation during activation SO MAGNETIC RESONANCE AND BRAIN FUNCTION: APPROACHES FROM PHYSICS SE PROCEEDINGS OF THE INTERNATIONAL SCHOOL OF PHYSICS ENRICO FERMI LA English DT Proceedings Paper CT International School of Physics Enrico Fermi on Magnetic Resonance and Brain Function: Approaches from Physics CY JUN 23-JUL 03, 1998 CL VARENNA LAKE COMO, ITALY SP Int Sch Phys Enrico Fermi ID CEREBRAL BLOOD-FLOW; POSITRON EMISSION TOMOGRAPHY; CENTRAL-NERVOUS-SYSTEM; NITRIC-OXIDE; SOMATOSENSORY STIMULATION; OXIDATIVE-METABOLISM; ENDOTHELIAL-CELLS; SKELETAL-MUSCLE; NEURAL ACTIVITY; RAT BRAINS C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Budinger, TF (reprint author), Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 57 TC 1 Z9 1 U1 0 U2 0 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS BN 90-5199-501-6 J9 P INT SCH PHYS PY 1999 VL 139 BP 395 EP 410 PG 16 WC Physics, Applied; Radiology, Nuclear Medicine & Medical Imaging SC Physics; Radiology, Nuclear Medicine & Medical Imaging GA BP87P UT WOS:000086455800011 ER PT B AU Budinger, TF Lenkinski, RE AF Budinger, TF Lenkinski, RE BE Maraviglia, B TI Na+ and K+ multiple and single quantum MRI potential for studying brain function SO MAGNETIC RESONANCE AND BRAIN FUNCTION: APPROACHES FROM PHYSICS SE PROCEEDINGS OF THE INTERNATIONAL SCHOOL OF PHYSICS ENRICO FERMI LA English DT Proceedings Paper CT International School of Physics Enrico Fermi on Magnetic Resonance and Brain Function: Approaches from Physics CY JUN 23-JUL 03, 1998 CL VARENNA LAKE COMO, ITALY SP Int Sch Phys Enrico Fermi ID INTRACELLULAR SODIUM ACTIVITY; NUCLEAR-MAGNETIC-RESONANCE; PERFUSED RAT-HEART; FILTERED NA-23 NMR; FERRET VENTRICULAR MUSCLE; CARDIAC PURKINJE-FIBERS; CALCIUM PARADOX; CELLULAR-ENERGY; ISCHEMIA; INHIBITION C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. RP Budinger, TF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, MS55-121,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Lenkinski, Robert/F-9045-2014 NR 45 TC 1 Z9 1 U1 0 U2 1 PU I O S PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS BN 90-5199-501-6 J9 P INT SCH PHYS PY 1999 VL 139 BP 411 EP 425 PG 15 WC Physics, Applied; Radiology, Nuclear Medicine & Medical Imaging SC Physics; Radiology, Nuclear Medicine & Medical Imaging GA BP87P UT WOS:000086455800012 ER PT S AU Granado, E Moreno, NO Garcia, A Sanjurjo, JA Rettori, C Torriani, I Oseroff, SB Neumeier, JJ McClellan, KJ Cheong, SW Tokura, Y AF Granado, E Moreno, NO Garcia, A Sanjurjo, JA Rettori, C Torriani, I Oseroff, SB Neumeier, JJ McClellan, KJ Cheong, SW Tokura, Y BE Missell, FP TI Raman scattering in CMR manganites SO MAGNETISM, MAGNETIC MATERIALS AND THEIR APPLICATIONS SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 4th Latin American Workshop on Magnetism, Magnetic Materials and Their Applications CY JUN 07-11, 1998 CL SAO PAULO, BRAZIL SP Fundacao Amparo Pesquisa Estado Sao Paulo, Conselho Nacl Desenvolvimento Cient & Tecnologico, Coordenadoria Aperfeicoamento Pessoal Nivel Super, Universidad Sao Paulo, Pro Reitoria Pesquisa, Centro Latino Americano Fis, Int Ctr Theoret Phys, Int Union Crystallog, CGA Analit DE colossal magnetoresistance; frequency shifts; Raman effect AB Polarized Raman spectra of single and polycrystalline La1-xSrxMnO3 ceramic samples were studied as a function of temperature. For the rhombohedral LaMnO3.1 and La0.7Sr0.3MnO3, the observed Raman peaks were associated to modes arising from the folding of the Brillouin zone under lattice deformation. For the orthorhombic LaMnO3.0, the Raman spectra are consistent with the Pnma structure and show an anomalous softening of the 494 and 604 cm(-1) modes below the antiferromagnetic ordering temperature, T-N similar or equal to 140 K. C1 UNICAMP, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. San Diego State Univ, San Diego, CA 92182 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. AT&T Bell Labs, Murray Hill, NJ 07974 USA. Univ Tokyo, Dept Phys, Tokyo 113, Japan. RP Granado, E (reprint author), UNICAMP, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. RI Rettori, Carlos/C-3966-2012; Granado, Eduardo/F-5389-2012; Moreno, Nelson/H-1708-2012; Tokura, Yoshinori/C-7352-2009; Torriani, Iris/E-5686-2010; Inst. of Physics, Gleb Wataghin/A-9780-2017 OI Rettori, Carlos/0000-0001-6692-7915; Moreno, Nelson/0000-0002-1672-4340; NR 8 TC 0 Z9 0 U1 0 U2 4 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-827-3 J9 MATER SCI FORUM PY 1999 VL 302-3 BP 134 EP 138 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BN23T UT WOS:000081205300020 ER PT B AU Balhorn, R Cosman, M Thornton, K Krishnan, VV Corzett, M Bench, G Kramer, C Lee, J Hud, NV Allen, M Prieto, M Meyer-Ilse, W Brown, JT Kirz, J Zhang, X Bradbury, EM Maki, G Braun, RE Breed, V AF Balhorn, R Cosman, M Thornton, K Krishnan, VV Corzett, M Bench, G Kramer, C Lee, J Hud, NV Allen, M Prieto, M Meyer-Ilse, W Brown, JT Kirz, J Zhang, X Bradbury, EM Maki, G Braun, RE Breed, V BE Gagnon, C TI Protamine mediated condensation of DNA in mammalian sperm. SO MALE GAMETE: FROM BASIC SCIENCE TO CLINICAL APPLICATIONS LA English DT Proceedings Paper CT 8th International Symposium on Spermatology CY AUG 17-22, 1998 CL MONTREAL, CANADA ID AMINO-ACID-SEQUENCE; ATOMIC-FORCE MICROSCOPY; NUCLEAR BASIC-PROTEINS; X-RAY-DIFFRACTION; NUCLEOTIDE-SEQUENCE; SECONDARY STRUCTURE; CHROMATIN DECONDENSATION; RAMAN-SPECTROSCOPY; MOUSE PROTAMINE-1; MAJOR PROTAMINE C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. RP Balhorn, R (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. NR 83 TC 54 Z9 55 U1 1 U2 3 PU CACHE RIVER PRESS PI VIENNA PA 2850 OAK GROVE ROAD, VIENNA, IL 62995 USA BN 1-889899-03-8 PY 1999 BP 55 EP 70 PG 16 WC Reproductive Biology SC Reproductive Biology GA BQ95N UT WOS:000165104200007 ER PT J AU Gawande, K Wheeler, T AF Gawande, K Wheeler, T TI Measures of effectiveness for governmental organizations SO MANAGEMENT SCIENCE LA English DT Article DE measures of effectiveness; government agencies; Poisson models; missing data ID MORAL HAZARD; PERFORMANCE AB For organizations whose objective is not necessarily the maximization of a financial quantity, there is little written in the economics and management literature about methods that quantify their effectiveness. Potential users of such methodologies are typically governmental organizations and agencies to whom Congress allocates funding periodically, but may also include many nonprofit organizations. Such research is importantly needed because government is no longer making outlay allocations on a merely historical basis, but is using as a criterion how effectively an organization uses its resources in meeting its objectives. In this paper we analyze the Maritime Safety Program of the U.S. Coast: Guard (USCG), which is responsible for monitoring the quality of vessels that sail in U.S. waters, and present measures of effectiveness (MOEs) for the Program. We do this at two levels of activity: at an overall program level (Level I) and at a component activity level (Level II). Poisson models are used to construct the MOEs using data on maritime casualties (accidents) between 1990-1993 from the real-time Marine Safety Management System (MSMS) database maintained by the Coast Guard. A feature of the empirical methodology is the Bayesian imputation of missing data. The MOEs constructed here have at least four important uses. First, as the name suggests, they perform the function that financial quantities such as returns on equity or returns on sales perform for private-sector organizations-that is, they are indicators of efficiency. Second,they can be used as inputs into allocative decisions within the organization. For example, the Level II MOEs can be used as inputs into a programming problem that determines the optimal allocation of resources among component activities. Third, internal performance evaluation across USCG Programs or across Port Units (called Marine safety Offices) can be based on their respective Level I MOEs. Fourth, and possibly the most important long-run consideration, MOEs provide the basis for better regulation by the government. Without MOEs the nature of regulation is probably suboptimal. By adopting these MOEs as criteria, it will be easier for the government to redesign those aspects of its regulation of the Coast Guard which curtail incentives. C1 Univ New Mexico, Dept Econ, Albuquerque, NM 87131 USA. Sandia Natl Labs, Environm Risk Assessment & Regulatory Anal Dept, Albuquerque, NM 87185 USA. RP Gawande, K (reprint author), Univ New Mexico, Dept Econ, Albuquerque, NM 87131 USA. NR 18 TC 10 Z9 10 U1 1 U2 6 PU INST OPERATIONS RESEARCH MANAGEMENT SCIENCES PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2909 USA SN 0025-1909 J9 MANAGE SCI JI Manage. Sci. PD JAN PY 1999 VL 45 IS 1 BP 42 EP 58 DI 10.1287/mnsc.45.1.42 PG 17 WC Management; Operations Research & Management Science SC Business & Economics; Operations Research & Management Science GA 229VB UT WOS:000082215500004 ER PT B AU Gatley, SJ Volkow, ND Makriyannis, A AF Gatley, SJ Volkow, ND Makriyannis, A BE Nahas, GG Sutin, KM Harvey, D Agurell, S Pace, N Cancro, R TI Studies of the brain cannabinoid system using positron and single-photon emission tomography SO MARIHUANA AND MEDICINE LA English DT Proceedings Paper CT Conference on Marihuana and Medicine CY MAR 20-21, 1998 CL NEW YORK UNIV SCH MED, NEW YORK, NY SP Stuart Mott Fdn, Helen Clay Frick Fdn, Jeremiah Milibank Fdn, Astra Pain Control, Swedish Acad Pharm Sci HO NEW YORK UNIV SCH MED ID TRANSPORTER IN-VIVO; GLUCOSE-METABOLISM; INTRAVENOUS DEXTROAMPHETAMINE; CEREBRAL METABOLISM; SYNAPTIC DOPAMINE; C-11 RACLOPRIDE; RAT-BRAIN; RECEPTOR; PET; BINDING C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Gatley, SJ (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. NR 62 TC 0 Z9 0 U1 1 U2 1 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DR, STE 208, TOTOWA, NJ 07512-1165 USA BN 0-89603-593-X PY 1999 BP 163 EP 176 PG 14 WC Substance Abuse; Medicine, Legal; Pharmacology & Pharmacy SC Substance Abuse; Legal Medicine; Pharmacology & Pharmacy GA BM81E UT WOS:000079827200018 ER PT J AU Morrisey, DJ DeWitt, TH Roper, DS Williamson, RB AF Morrisey, DJ DeWitt, TH Roper, DS Williamson, RB TI Variation in the depth and morphology of burrows of the mud crab Helice crassa among different types of intertidal sediment in New Zealand SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE crab; burrow; bioturbation; geochemistry; sediment ID UCA-PUGNAX SMITH; TROPHIC MODES; FIDDLER-CRAB; SALT-MARSH; BIOTURBATION; WATER; ARCHITECTURE; IRRIGATION; DECAPODA; MANUKAU AB Crabs are among the larger and more active burrowers in intertidal sediments in New Zealand, as in many other parts of the world. Abundances of mud crabs Helice crassa and their burrows were compared among sites differing in the nature of their sediments. Differences in burrow architecture among sites were quantified using casts of burrows made in situ. The effects of bioturbation on sediment geochemistry were also determined with respect to redox potential and the concentrations of 2 chemical phases, acid volatile sulphides (AVS) and iron pyrites (FeS2), that influence the bioavailability of heavy metals. The objective of this study was to identify effects of differences in the extent and nature of burrowing activity of the crab H. crassa among different sediment types on sediment geochemistry, particularly with respect to the bioavailability of heavy metals. Burrows were more abundant at muddy sites (average 22 to 59 burrows 20 cm diameter core(-1)) than at sandy sites (average 12 burrows core(-1)). Although not necessarily deeper at muddy sites, burrows were more complex in structure. Average volumes of casts were larger at muddy than sandy sites by a factor of up to 14.8 and at the most densely-burrowed site, burrows represented 14 % of the volume of the surrounding sediment. The architecture of the burrows of H, crassa is discussed in the context of published models of burrow structure and function for other crustacea. Patterns of differences in chemical variables among sites were not clear cut. Redox profiles generally showed decreases with depth in the sediment and, among the muddy sites, potentials were highest and most variable at the site with greatest burrowing activity. Concentrations of AVS and FeS2 were lower in sandy sediments than in muddy ones. Among muddy sites, the concentration of AVS was lowest at the site with the greatest amount of burrowing, consistent with introduction of oxygen to the sediment and the consequent oxidation of AVS. Concentrations of FeS2 showed a pattern that suggested that burrowing introduces FeS2 from deeper layers, where concentrations are higher, into shallower, bioturbated layers of the sediment, offsetting effects of oxidation due to burrowing activity. Concentrations of FeS2 were highest at the site with most burrowing activity. C1 Natl Inst Water & Atmospher Res, Hamilton, New Zealand. Battelle Marine Sci Lab, Sequim, WA 98382 USA. RP Morrisey, DJ (reprint author), Natl Inst Water & Atmospher Res, POB 11-115, Hamilton, New Zealand. EM d.morrisey@niwa.cri.nz NR 47 TC 30 Z9 35 U1 2 U2 18 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PY 1999 VL 182 BP 231 EP 242 DI 10.3354/meps182231 PG 12 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA 214PK UT WOS:000081336200020 ER PT J AU Breitburg, DL Rose, KA Cowan, JH AF Breitburg, DL Rose, KA Cowan, JH TI Linking water quality to larval survival: predation mortality of fish larvae in an oxygen-stratified water column SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE behavioral responses; Chesapeake Bay; fish predator; food web; gelatinous zooplankton; Gobiosoma bosc; hypoxia; individual-based model ID LOW DISSOLVED-OXYGEN; CHESAPEAKE BAY; PLANKTIVOROUS FISH; STRIPED BASS; HYPOXIA; VULNERABILITY; SIZE; SCYPHOMEDUSAE; CTENOPHORES; POPULATIONS AB Low dissolved oxygen concentrations can affect growth rates, distributions and predator-prey interactions of aquatic organisms. Each of these potential effects is generally examined separately in laboratory and field studies. As a result, it is often difficult to determine the net influence of low oxygen on survival and which individual effect of low oxygen contributes most to mortality. We used a spatially explicit individual-based predation model to predict how effects of low dissolved oxygen on vertical distributions, predation rates, and larval growth combine to influence survival of estuarine fish larvae in a water column where the subpycnocline (bottom) and pycnocline layers are subject to oxygen depletion, We analyzed simulations involving 3 predators (scyphomedusae based on Chrysaora quinquecirrha, and fish that were relatively sensitive to, or tolerant of, low dissolved oxygen), water columns that differed in the relative thickness of the subpycnocline layer, and bottom dissolved oxygen concentrations ranging from cl mg l(-1) to no-effect concentrations. The effect of dissolved oxygen on larval and predator Vertical distributions, predator capture success and larval growth rates in simulations were based on previous experiments and field sampling in the Patuxent River. a tributary of the Chesapeake Bay, USA. Simulations indicated that bottom dissolved oxygen can strongly affect predation mortality of fish larvae. Thus, there is the potential for eutrophication to have a large effect on larval fish survival, and possibly recruitment, even in the absence of direct effects of low oxygen-induced mortality of larvae or the effects of nutrient enrichment on the abundance of larval prey or predators. Depending on predator characteristics and water column depth, lowest larval survival occurred when oxygen concentrations were either <1 mg l(-1) or sufficiently high that oxygen concentration had no effect on distributions or capture rates; highest survival generally occurred with hypoxic bottom layers (1 to 2 mg l(-1) dissolved oxygen). Bottom dissolved oxygen concentration also strongly affected the relative importance of fish and sea nettle predation in simulations that included both types of predators. Differences among predator types had important consequences for the magnitude and location of predation. Bottom-layer oxygen depletion shifted the focus of trophic interactions into the pycnocline and surface layers. Additional simulations indicated that distributional and capture success effects on larval survival were more important than growth rate effects, and that the direction of effects depended on the predator type and dissolved oxygen concentrations. Limitations of the model as well as implications of results for efforts to reduce nutrient loadings into estuaries are discussed. C1 Natl Acad Sci, Estuarine Res Ctr, St Leonard, MD 20678 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ S Alabama, Dauphin Isl Sea Lab, Dauphin Island, AL 36528 USA. RP Breitburg, DL (reprint author), Natl Acad Sci, Estuarine Res Ctr, 10545 Mackall Rd, St Leonard, MD 20678 USA. EM breit@acnatsci.org NR 54 TC 58 Z9 59 U1 4 U2 27 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PY 1999 VL 178 BP 39 EP 54 DI 10.3354/meps178039 PG 16 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA 188ZD UT WOS:000079878600004 ER PT J AU McLuckey, SA Stephenson, JL AF McLuckey, SA Stephenson, JL TI Ion/ion chemistry of high-mass multiply charged ions (vol. 17, pg. 369, 1998) SO MASS SPECTROMETRY REVIEWS LA English DT Correction ID PROTON-TRANSFER REACTIONS; INFRARED RADIATIVE DISSOCIATION; COLLISION-INDUCED DISSOCIATION; PHASE ELECTRON-TRANSFER; CYTOCHROME-C IONS; GAS-PHASE; MOLECULE REACTIONS; PROTEIN CATIONS; OLIGONUCLEOTIDE ANIONS; CHEMICAL-IONIZATION C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP McLuckey, SA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI McLuckey, Scott/B-2203-2009 OI McLuckey, Scott/0000-0002-1648-5570 NR 108 TC 3 Z9 3 U1 0 U2 5 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0277-7037 J9 MASS SPECTROM REV JI Mass Spectrom. Rev. PD JAN-FEB PY 1999 VL 18 IS 1 BP 83 EP 86 DI 10.1002/(SICI)1098-2787(1999)18:1<83::AID-MAS4>3.0.CO;2-N PG 4 WC Spectroscopy SC Spectroscopy GA 231PL UT WOS:000082318900004 ER PT B AU Rodriguez, JG Carlson, NM Blackwood, LG Larson, TK AF Rodriguez, JG Carlson, NM Blackwood, LG Larson, TK BE Bank, LC TI Field measurements on a composite bridge SO MATERIALS AND CONSTRUCTION: EXPLORING THE CONNECTION LA English DT Proceedings Paper CT 5th ASCE Materials Engineering Congress (MatCong5) CY MAY 10-12, 1999 CL CINCINNATI, OH SP Amer Soc Civil Engineers AB A 30-ft long, 18-ft wide polymer matrix composite (PMC) bridge is being field tested with live loads. During the year and a half of field testing at the Idaho National Engineering and Environmental Laboratory (INEEL), dynamic and static load data have been acquired and analyzed. In addition, accelerated aging research on samples of the composite material and candidate ultraviolet (UV) protective coatings is determining the effects of six environmental factors on material durability. Durability and sensor data provide information required for determining the cost/benefit measures to use in life-cycle planning, determining a maintenance strategy, establishing applicable inspection techniques, and for establishing guidelines, standards, and acceptance criteria for PMC use in the transportation infrastructure. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Rodriguez, JG (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0423-2 PY 1999 BP 308 EP 315 PG 2 WC Construction & Building Technology; Engineering, Civil; Materials Science, Multidisciplinary SC Construction & Building Technology; Engineering; Materials Science GA BP25J UT WOS:000084506000040 ER PT S AU Fleming, JG Lin, SY AF Fleming, JG Lin, SY BE Vladimirsky, Y Friedrich, CR TI 3-D silicon photonic lattices- cornerstone of an emerging photonics revolution SO MATERIALS AND DEVICE CHARACTERIZATION IN MICROMACHINING II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Materials and Device Characterization in Micromachining II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Stand & Technol, Sandia Natl Labs, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliabil Engn Assoc Japan DE photonic lattice; MEMS; infrared; photonic bandgap ID BAND-GAP; CRYSTAL; WAVELENGTHS AB Three-dimensional photonic lattices are engineered "materials" which are the photonic analogues of semiconductors. These structures were first proposed and demonstrated in the mid-to-late 1980's. However, due to fabrication difficulties, lattices active in the infrared are only just emerging. Wide ranges of structures and fabrication approaches have been investigated. The most promising approach for many potential applications is a diamond-like structure fabricated using silicon microprocessing techniques. This approach has enabled the fabrication of 3-D silicon photonic lattices active in the infrared. The structures display band gaps centered from 12 mu down to 1.55 mu. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Fleming, JG (reprint author), Sandia Natl Labs, POB 5800,Org 1723,MS 1084, Albuquerque, NM 87185 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3472-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3875 BP 9 EP 18 PG 10 WC Engineering, Civil; Materials Science, Characterization & Testing; Optics SC Engineering; Materials Science; Optics GA BP12S UT WOS:000084200000002 ER PT S AU Jensen, BD Bitsie, F de Boer, M AF Jensen, BD Bitsie, F de Boer, M BE Vladimirsky, Y Friedrich, CR TI Interferometric measurement for improved understanding of boundary effects in micromachined beams SO MATERIALS AND DEVICE CHARACTERIZATION IN MICROMACHINING II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Materials and Device Characterization in Micromachining II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Stand & Technol, Sandia Natl Labs, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliabil Engn Assoc Japan DE material properties; step-up anchor; surface micromachining; interferometry AB Micromachined beams are commonly used to measure material properties in MEMS. Such measurements are complicated by the fact that boundary effects at the ends of the beams have a significant effect on the properties being measured. In an effort to improve the accuracy and resolution of such measurements, we are conducting a study of support post compliances in cantilever and fixed-fixed beams. Three different support post designs have been analyzed by finite element modeling. The results are then compared to measurements made on actual devices using interferometry. Using this technique, the accuracy of measurements of Young's modulus has been improved. Continuing work will also improve the measurement of residual stress. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Jensen, BD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 10 TC 19 Z9 19 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3472-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3875 BP 61 EP 72 DI 10.1117/12.360480 PG 12 WC Engineering, Civil; Materials Science, Characterization & Testing; Optics SC Engineering; Materials Science; Optics GA BP12S UT WOS:000084200000007 ER PT S AU de Boer, MP Jensen, BD Bitsie, F AF de Boer, MP Jensen, BD Bitsie, F BE Vladimirsky, Y Friedrich, CR TI A small area in-situ MEMS test structure to measure fracture strength by electrostatic probing SO MATERIALS AND DEVICE CHARACTERIZATION IN MICROMACHINING II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Materials and Device Characterization in Micromachining II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Stand & Technol, Sandia Natl Labs, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliabil Engn Assoc Japan ID THIN-FILMS; MECHANICAL-PROPERTIES; SILICON AB We have designed, fabricated, tested and modeled a first generation small area test structure for MEMS fracture studies by electrostatic rather than mechanical probing. Because of its small area, this device has potential applications as a lot monitor of strength or fatigue of the MEMS structural material. By matching deflection versus applied voltage data to a 3-D model of the test structure, we develop high confidence that the local stresses achieved in the gage section are greater than 1 GPa. Brittle failure of the polycrystalline silicon was observed. C1 Sandia Natl Labs, Dept 1725, Albuquerque, NM 87185 USA. RP de Boer, MP (reprint author), Sandia Natl Labs, Dept 1725, POB 5800, Albuquerque, NM 87185 USA. NR 27 TC 13 Z9 13 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3472-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3875 BP 97 EP 103 DI 10.1117/12.360459 PG 7 WC Engineering, Civil; Materials Science, Characterization & Testing; Optics SC Engineering; Materials Science; Optics GA BP12S UT WOS:000084200000011 ER PT S AU Moldovan, N AF Moldovan, N BE Vladimirsky, Y Friedrich, CR TI Deformation and stress in PMMA during hard X-ray exposure for deep lithography SO MATERIALS AND DEVICE CHARACTERIZATION IN MICROMACHINING II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Materials and Device Characterization in Micromachining II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Stand & Technol, Sandia Natl Labs, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliabil Engn Assoc Japan DE LIGA; deep lithography; hard X-rays; stress; PMMA; radiation effects AB The availability of high-energy, high-flux, collimated synchrotron radiation has extended the application of deep X-ray lithography (DXRL) to thickness values of the PMMA resist of several millimeters. Some of the most severe limitations come from plastic deformation, stress, and cracks induced in PMMA during exposure and development. We have observed and characterized these phenomena quantitatively. Profilometry measurements revealed that the PMMA is subjected either to local shrinkage or to expansion, while compression and expansion evolve over time. Due to material loss and crosslinking, the material undergoes a shrinkage, while the radiation-induced decomposition generates gases expanding the polymer matrix. The overall dynamics of the material microrelief and stress during and after the exposure depend on the balance between compaction and outgassing. These depend in turn on the exposure conditions (spectrum, dose, dose rate, scanning, temperature), post-exposure storage conditions, PMMA material properties and thickness, and also on the size and geometry of the exposed patterns. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Moldovan, N (reprint author), Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 9 TC 5 Z9 5 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3472-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3875 BP 155 EP 163 DI 10.1117/12.360466 PG 9 WC Engineering, Civil; Materials Science, Characterization & Testing; Optics SC Engineering; Materials Science; Optics GA BP12S UT WOS:000084200000018 ER PT S AU Albright, KL Bradley, JM AF Albright, KL Bradley, JM BE Goodnick, SM Kailey, WF Longshore, RE Zhang, YH TI Avalanche photodiode array sensor with high-speed CCD delay line readout SO MATERIALS AND ELECTRONICS FOR HIGH-SPEED AND INFRARED DETECTORS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Materials and Electronics for High-Speed and Infrared Detectors CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE MCM; APD; CCD delay line; high-speed imaging AB A prototype solid-state multi-chip-module (MCM) optical sensor circuit is described. The MCM is designed to sample the optical signals from a fiber-optic array at rates up to 200 MHz. The fiber-optic inputs interface to the MCM avalanche-photodiode (APD) sensor array. The prototype 40 pixel MCM stores approximately 1000 samples from each fiber before readout. This is done on the MCM using high-speed charge-injection input CCD delay line ICs. The MCM is designed to be cooled to 0 degrees C. This stabilizes the APD gain and minimizes dark current generation in the APD and the CCD delay line. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Albright, KL (reprint author), Univ Calif Los Alamos Natl Lab, MS D454, Los Alamos, NM 87545 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3280-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3794 BP 143 EP 147 DI 10.1117/12.366740 PG 5 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Materials Science, Multidisciplinary; Optics SC Engineering; Instruments & Instrumentation; Materials Science; Optics GA BN98D UT WOS:000083742300017 ER PT J AU Pint, BA Tortorelli, PF Wright, IG AF Pint, BA Tortorelli, PF Wright, IG TI Long-term oxidation performance of ingot-produced Fe3Al alloys SO MATERIALS AT HIGH TEMPERATURES LA English DT Article DE ODS FeCrAl; Fe3Al alloys; oxidation performance; reactive element additions; lifetime prediction ID FE-CR-AL; HIGH-TEMPERATURE OXIDATION; CYCLIC OXIDATION; REACTIVE-ELEMENT; IRON ALUMINIDES; SCALE ADHESION; AL2O3 SCALES; BASE ALLOYS; OXIDE; BEHAVIOR AB The oxidation performance of ingot-produced Fe-28at.%Al-(2-5)%Cr alloys with minor oxygen-active element additions was examined in long-term exposures at 1,000-1,300 degrees C. As expected for alumina-forming alloys, additions of Zr, Y and Hf improved the oxidation behavior of these alloys. At the lower end of the temperature range, these alloys performed similarly to other iron-base alumina-formers. However, at higher temperatures, scale spallation was increased and significant deformation of the substrate was observed. This type of scale spallation was not observed on other alumina-formers. Oxidation data were used to predict times to breakaway for this temperature range. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Pint, BA (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Wright, Ian/A-8300-2008; Pint, Bruce/A-8435-2008; Tortorelli, Peter/E-2433-2011 OI Pint, Bruce/0000-0002-9165-3335; NR 53 TC 32 Z9 32 U1 0 U2 4 PU SCIENCE REVIEWS 2000 LTD PI ST ALBANS PA PO BOX 314, ST ALBANS AL1 4ZG, HERTS, ENGLAND SN 0960-3409 EI 1878-6413 J9 MATER HIGH TEMP JI Mater. High Temp. PY 1999 VL 16 IS 1 BP 1 EP 13 DI 10.3184/096034099783641236 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 205QR UT WOS:000080832500001 ER PT J AU Haynes, JA Ferber, MK Porter, WD Rigney, ED AF Haynes, JA Ferber, MK Porter, WD Rigney, ED TI Mechanical properties and fracture behavior of interfacial alumina scales on plasma-sprayed thermal barrier coatings SO MATERIALS AT HIGH TEMPERATURES LA English DT Article DE TBCs; thermal barrier coatings; alumina scales; alumina fracture; plasma-sprayed coatings ID HIGH-TEMPERATURE CORROSION; OXIDE SCALES; REACTIVE-ELEMENT; ISOTHERMAL OXIDATION; FAILURE MECHANISMS; ALLOYS; DEGRADATION; ADHERENCE; YTTRIUM; SEGREGATION AB The mechanical properties and fracture behavior of Y-doped Al2O3 scales were investigated by furnace thermal cycling (to 1,150 degrees C) of plasma-sprayed thermal barrier coatings (TBCs) with vacuum plasma-sprayed (VPS) or air plasma-sprayed (APS) Ni-22Cr-10Al-1Y bond coatings. No significant alterations in Al2O3 hardness or Young's modulus (as measured by mechanical properties microprobe) were detected as a function of bond coat type, exposure time, or number of thermal cycles. The interfacial Al2O3 scales on VPS NiCrAlY exhibited progressive increases in localized fracture, buckling, and delamination during thermal cycling. The concentration of arrayed lenticular voids in the columnar Al2O3 grain boundaries significantly increased during cyclic oxidation (as compared to isothermal oxidation), but only in scales which formed on convex surfaces, suggesting internal void growth was stress-related. The amount and frequency of scare damage was higher on convex surfaces with a relatively lame radius of curvature as compared to convex surfaces with a very small radius of curvature. Although the thermo-mechanical fracture resistance of Al2O3 scales on APS NiCrAlY was superior to scales on VPS NiCrAlY, TBC lifetimes on VPS NiCrAlY were greater by a factor of 2. Apparently, severe interfacial scale damage did not rapidly degrade the adherence of the ceramic top coatings. C1 Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. Univ Alabama Birmingham, Dept Mech & Mat Engn, Birmingham, AL 35923 USA. RP Haynes, JA (reprint author), Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. NR 51 TC 21 Z9 25 U1 1 U2 5 PU SCIENCE REVIEWS 2000 LTD PI ST ALBANS PA PO BOX 314, ST ALBANS AL1 4ZG, HERTS, ENGLAND SN 0960-3409 EI 1878-6413 J9 MATER HIGH TEMP JI Mater. High Temp. PY 1999 VL 16 IS 2 BP 49 EP 69 DI 10.3184/096034099783641191 PG 21 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 263LE UT WOS:000084125500001 ER PT J AU Vaubert, VM Janney, MA Stinton, DP AF Vaubert, VM Janney, MA Stinton, DP TI Development of slurry-based Ca0.5Sr0.5Zr4(PO4)(6) (CS-50) coatings for SiC in fossil energy applications SO MATERIALS AT HIGH TEMPERATURES LA English DT Article DE CS-50 coatings; sulfate salt corrosion ID THERMAL-EXPANSION; CORROSION; CERAMICS; 1000-DEGREES-C AB Coatings of Ca,,Sr,,Zr,(PO,), (CS-50), an ultra-low thermal-expansion material, have been successfully developed to protect SiC-based materials from sulfate salt corrosion. The coatings were applied to fiber-reinforced, SiC-matrix composite heat exchanger tubes and clay-bonded SIG. Aqueous slurries were prepared and applied to the SiC substrates. One coating process for heat exchanger material substrates, consisted of mechanically dipping the samples in a slip. A spin-coating process has also been developed that produced thin, non-obstructing coatings for hot-gas filter substrates. The thermal shock and corrosion resistance of coated parts were evaluated, and preliminary results are encouraging for the use of CS-50 as a protective coating. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Vaubert, VM (reprint author), Oak Ridge Natl Lab, POB 2008,Bldg 4515,MS-6063, Oak Ridge, TN 37831 USA. NR 11 TC 1 Z9 1 U1 1 U2 2 PU SCIENCE & TECHNOLOGY LETTERS PI NORTHWOOD PA PO BOX 81,, NORTHWOOD, MIDDX, ENGLAND HA6 3DN SN 0960-3409 J9 MATER HIGH TEMP JI Mater. High Temp. PY 1999 VL 16 IS 4 BP 175 EP 180 DI 10.3184/096034099783641092 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 287QC UT WOS:000085516300003 ER PT J AU Brady, MP Zhu, JH Liu, CT Tortorelli, PF Walker, LR McKamey, CG Wright, JL Carmichael, CA Larson, DJ Miller, MK Porter, WD AF Brady, MP Zhu, JH Liu, CT Tortorelli, PF Walker, LR McKamey, CG Wright, JL Carmichael, CA Larson, DJ Miller, MK Porter, WD TI Intermetallic reinforced Cr alloys for high-temperature use SO MATERIALS AT HIGH TEMPERATURES LA English DT Article DE intermetallic reinforced Cr alloys; Cr; oxidation; Laves phase; mechanical properties; MgO AB A new family of Cr(Ta)-Cr(2)Ta intermetallic alloys based on Cr-(6-10)Ta (at%) is currently under development for structural use in oxidizing environments in the 1,000-1,300 degrees C temperature range. These alloys show excellent strength and creep resistance and good oxidation resistance at high temperatures in air. Oxidation resistance comparable to commercial reactive element doped chromia-forming alloys and creep resistance comparable to single-crystal superalloys have been demonstrated. To date, only modest room-temperature fracture toughness (in the 11-12 MPa m(1/2) range) has been achieved. Preliminary results of a promising approach to improve room-temperature fracture toughness via ductilization of Cr with MgO additions are discussed. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Brady, MP (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Brady, Michael/A-8122-2008; OI Brady, Michael/0000-0003-1338-4747; Liu, Chain Tsuan/0000-0001-7888-9725 NR 12 TC 12 Z9 13 U1 0 U2 0 PU SCIENCE REVIEWS 2000 LTD PI ST ALBANS PA PO BOX 314, ST ALBANS AL1 4ZG, HERTS, ENGLAND SN 0960-3409 J9 MATER HIGH TEMP JI Mater. High Temp. PY 1999 VL 16 IS 4 BP 189 EP 193 DI 10.3184/096034099783641047 PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 287QC UT WOS:000085516300005 ER PT J AU Probst, KJ Besmann, TM McLaughlin, JC Anderson, TJ Starr, TL AF Probst, KJ Besmann, TM McLaughlin, JC Anderson, TJ Starr, TL TI Development of a scaled-up chemical vapor infiltration system for tubular geometries SO MATERIALS AT HIGH TEMPERATURES LA English DT Article DE chemical vapor infiltration; fiber-reinforced SiC; composites AB Silicon carbide-based heat exchanger tubes are of interest to energy production and conversion systems due to their excellent high temperature properties. Fiber-reinforced SiC is of particular importance for these applications since it is substantially tougher than monolithic SiC, and therefore more damage and thermal shock tolerant. This paper reviews a program to develop a scaled-up system for the chemical vapor infiltration of tubular shapes of fiber-reinforced SiC. The efforts include producing a unique furnace design, extensive process and system modeling, and experimental efforts to demonstrate tube fabrication. C1 Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Univ Louisville, Dept Chem Engn, Louisville, KY 40292 USA. RP Probst, KJ (reprint author), Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. NR 5 TC 3 Z9 3 U1 1 U2 3 PU SCIENCE & TECHNOLOGY LETTERS PI NORTHWOOD PA PO BOX 81,, NORTHWOOD, MIDDX, ENGLAND HA6 3DN SN 0960-3409 J9 MATER HIGH TEMP JI Mater. High Temp. PY 1999 VL 16 IS 4 BP 201 EP 205 DI 10.3184/096034099783641100 PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 287QC UT WOS:000085516300007 ER PT J AU Maziasz, PJ Swindeman, RW Montague, JP Fitzpatrick, M Browning, PF Grubb, JF Klug, RC AF Maziasz, PJ Swindeman, RW Montague, JP Fitzpatrick, M Browning, PF Grubb, JF Klug, RC TI Improved creep-resistance of austenitic stainless steel for compact gas turbine recuperators SO MATERIALS AT HIGH TEMPERATURES LA English DT Article DE austenitic stainless steel; compact gas turbine recuperators ID SWELLING RESISTANCE AB Primary surface recuperators (PSRs) are compact heat-exchangers made from thin-foil type 347 austenitic stainless steel, which boost the efficiency of land-based gas turbine engines. Compact recuperators are also an essential technology for some new microturbines. Solar turbines uses foil folded into a unique corrugated pattern to maximize the primary surface area for efficient heat transfer between hot exhaust gas on one side, and the compressor discharge air on the other side of the foil. Allegheny-Ludlum produces 0.003-0.004 inches thick foil for a range of current turbine engines using PSRs that operate up to 660 degrees C. One goal of this team-effort project is to modify the processing to enable improved creep resistance of such 347 stainless steel foils at 650-700 degrees C. Laboratory-scale processing modification experiments recently have demonstrated that dramatic improvements can be achieved in the creep resistance of such typical 347 stainless steel foils. The modified processing enables fine NbC carbide precipitates to develop during creep at 650-700 degrees C, which provides strength even with a fine grain size. Such improved creep-resistance allows greater flexibility in optimizing the cost-performance relationship as increased demands are placed on the PSR at higher operating temperatures. The next challenges are to better understand the nature of the improved creep resistance in these 347 stainless steel foil, and to achieve similar improvements with scale-up to commercial foil production. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Solar Turbines Inc, San Diego, CA USA. Allegheny Ludlum, Brackenridge, PA USA. Allegheny Ludlum, Wallingford, CT USA. Allegheny Ludlum, Leechburg, PA USA. RP Maziasz, PJ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. OI Maziasz, Philip/0000-0001-8207-334X NR 17 TC 15 Z9 16 U1 0 U2 4 PU SCIENCE & TECHNOLOGY LETTERS PI NORTHWOOD PA PO BOX 81,, NORTHWOOD, MIDDX, ENGLAND HA6 3DN SN 0960-3409 J9 MATER HIGH TEMP JI Mater. High Temp. PY 1999 VL 16 IS 4 BP 207 EP 212 DI 10.3184/096034099783641083 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 287QC UT WOS:000085516300008 ER PT J AU Ellingson, WA Koehl, ER Sun, JG Deemer, C Lee, H Spohnholtz, T AF Ellingson, WA Koehl, ER Sun, JG Deemer, C Lee, H Spohnholtz, T TI Development of nondestructive evaluation methods for hot gas filters SO MATERIALS AT HIGH TEMPERATURES LA English DT Article DE nondestructive evaluation; hot gas filters AB Rigid ceramic hot gas candle filters are currently under development for high-temperature hot gas particulate cleanup in advanced coal-based power systems. The ceramic materials for these filters include monolithics (usually non-oxides), oxide and non-oxide fiber-reinforced composites, and recrystallized silicon carbide. A concern of end users in using these types of filters, where over 3000 may be used in a single installation, is the lack of a data base on which to base decisions for reusing, replacing or predicting remaining life during plant shutdowns. One method to improve confidence of usage is to develop nondestructive evaluation (NDE) technology to provide surveillance methods for determination of the extent of damage or of life-limiting characteristics such as thermal fatigue, oxidation, damage from ash bridging such as localized cracking, damage from local burning, and elongation at elevated temperatures. Although in situ NDE methods would be desirable in order to avoid disassembly of the candle filter vessels, the possible presence of filter cakes and/or ash bridging, and the state of current NDE technology prevent this. Thus, off-line NDE methods, if demonstrated to be reliable, fast and cost effective, could be a significant step forward in developing confidence in utilization of rigid ceramic hot gas filters. Recently, NDE methods have been developed which show promise of providing information to build this confidence. Acousto-ultrasound, a totally nondestructive method, together with advanced digital signal processing, has been demonstrated to provide excellent correlation with remaining strength on new, as-produced filters, and for detecting damage in some monolithic filters when removed from service. Thermal imaging, with digital signal processing for determining through-wall thermal diffusivity, has also been demonstrated to correlate with remaining strength in both new (as-received) and in-service filters. impact acoustic resonance using a scanning laser vibrometer has been demonstrated to allow detection of changes in frequency which may be correlated to remaining strength. These methods have been shown to be applicable to clay-bonded SiC filters, recrystallized SIC filters, CVI-SiC composite filters and oxide composite filters. Other NDE methods under development include: (a) fast, high spatial-resolution X-ray imaging for detecting density variations and dimensional changes; (b) air-coupled ultrasonic methods for determining through-thickness compositional variations; and (c) acoustic emission technology with mechanical loading for detecting localized bulk damage. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Ellingson, WA (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 4 Z9 4 U1 0 U2 2 PU SCIENCE & TECHNOLOGY LETTERS PI NORTHWOOD PA PO BOX 81,, NORTHWOOD, MIDDX, ENGLAND HA6 3DN SN 0960-3409 J9 MATER HIGH TEMP JI Mater. High Temp. PY 1999 VL 16 IS 4 BP 213 EP 218 DI 10.3184/096034099783641074 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 287QC UT WOS:000085516300009 ER PT J AU Rawers, J Kwong, J Bennett, J AF Rawers, J Kwong, J Bennett, J TI Characterizing coal-gasifier slag-refractory interactions SO MATERIALS AT HIGH TEMPERATURES LA English DT Article DE coal-gasifier; slag-refractory interactions AB To characterize refractory degradation and loss in commercial coal-gasifier combined cycle power systems, cup-type tests were conducted on high chromium-alumina, sinter-bonded refractories under laboratory conditions designed to simulate commercial operations of temperature, atmosphere, and slag interactions. These tests provided qualitative results from which the slag-refractory interactions can be characterized. These high chromium refractories were generally inert with respect to the coal slag components. However, in this study preliminary findings did show (1) iron( oxide) in the slag reacted with chrome sesquioxide to produce a Cr-Fe spinel at the slag-refractory interface, and (2) chrome was soluble in the molten slag. Comparison of cup-type test results with data from operating commercial plants suggests that the principal loss of refractory material in a coal-gasifier combustion chamber is chrome dissolution into the slag. Tests are currently underway to determine if minor modifications to the combustion process might increase refractory Life. C1 US DOE, Albany Res Ctr, Albany, OR USA. RP Rawers, J (reprint author), US DOE, Albany Res Ctr, Albany, OR USA. NR 0 TC 19 Z9 20 U1 0 U2 4 PU SCIENCE & TECHNOLOGY LETTERS PI NORTHWOOD PA PO BOX 81,, NORTHWOOD, MIDDX, ENGLAND HA6 3DN SN 0960-3409 J9 MATER HIGH TEMP JI Mater. High Temp. PY 1999 VL 16 IS 4 BP 219 EP 222 DI 10.3184/096034099783641056 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 287QC UT WOS:000085516300010 ER PT J AU Czajkowski, CJ AF Czajkowski, CJ TI Evaluation of static eliminators containing polonium-210 SO MATERIALS CHARACTERIZATION LA English DT Article AB Six static eliminators containing radioactive polonium-210 microspheres were examined subsequent to a contamination incident at a commercial facility. It was found that cracked and broken microspheres were being produced and incorporated into new devices and even "as received" devices were potential sources of contamination. It is shown that rough handling of the devices may initiate polonium-210 leakage during or prior to service. The epoxy binder used in the devices appears to suffer significant environmental and material damage even under ambient conditions. The effects of solvents, heat, moisture, or vibration during service may accelerate this damage. The breakdown of the epoxy binder appears to be a significant contributor to the contamination by loose microspheres or microsphere fragments. (C) Elsevier Science Inc., 1999. All rights reserved. C1 Brookhaven Natl Lab, Environm & Waste Technol Ctr, Upton, NY 11973 USA. RP Czajkowski, CJ (reprint author), Brookhaven Natl Lab, Environm & Waste Technol Ctr, Upton, NY 11973 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-5803 J9 MATER CHARACT JI Mater. Charact. PD JAN PY 1999 VL 42 IS 1 BP 13 EP 20 DI 10.1016/S1044-5803(98)00042-4 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA 172ZD UT WOS:000078955500002 ER PT S AU Calaway, WF McCann, MP Pellin, MJ AF Calaway, WF McCann, MP Pellin, MJ BE Hepp, AF Prahl, JM Keith, TG Bailey, SG Fowler, JR TI Impurity characterization of solar wind collectors for the genesis discovery mission by resonance ionization mass spectrometry SO MATERIALS IN SPACE-SCIENCE, TECHNOLOGY AND EXPLORATION SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials in Space-Science, Technology and Exploration at the 1998 MRS Fall Meeting CY NOV 29-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc, NASA, Elsevier Sci Ltd ID SILICON; WAFERS AB NASA's Genesis Discovery Mission is designed to collect solar matter and return it to earth for analysis. The mission consists of launching a spacecraft that carries high purity collector materials, inserting the spacecraft into a halo orbit about the L perpendicular to sun-earth libration point, exposing the collectors to the solar wind for two years, and then returning the collectors to earth. The collectors will then be made available for analysis by various methods to determine the elemental and isotopic abundance of the solar wind. In preparation for this mission, potential collector materials are being characterized to determine baseline impurity levels and to assess detection limits for various analysis techniques. As part of the effort, potential solar wind collector materials have been analyzed using resonance ionization mass spectrometry (RIMS). RIMS is a particularly sensitivity variation of secondary neutral mass spectrometry that employs resonantly enhanced multiphoton ionization (REMPI) to selectively postionize an element of interest, and thus discriminates between low levels of that element and the bulk material. The high sensitivity and selectivity of RIMS allow detection of very low concentrations while consuming only small amounts of sample. Thus, RIMS is well suited for detection of many heavy elements in the solar wind, since metals heavier than Fe are expected to range in concentrations from 1 ppm to 0.2 ppt. In addition, RIMS will be able to determine concentration profiles as a function of depth for these implanted solar wind elements effectively separating them from terrestrial contaminants. RIMS analyses to determine Ti concentrations in Si and Ge samples have been measured. Results indicate that the detection limit for RIMS analysis of Ti is below 100 ppt for 10(6) averages. Background analyses of the mass spectra indicate that detection limits for heavier elements will be similar. Furthermore, detection limits near 1 ppt are possible with higher repetition rate lasers where it will be possible to increase signal averaging to 10(8) laser shots. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Calaway, WF (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Pellin, Michael/B-5897-2008 OI Pellin, Michael/0000-0002-8149-9768 NR 9 TC 7 Z9 7 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-457-2 J9 MATER RES SOC SYMP P PY 1999 VL 551 BP 83 EP 88 PG 6 WC Engineering, Aerospace; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BP33N UT WOS:000084731100010 ER PT J AU Covino, BS Cramer, SD Bullard, SJ Holcomb, GR Collins, WK McGill, GE AF Covino, BS Cramer, SD Bullard, SJ Holcomb, GR Collins, WK McGill, GE TI Thermal spray anodes for impressed current cathodic protection of reinforced concrete structures SO MATERIALS PERFORMANCE LA English DT Article AB Differences between thermal spray Zn and catalyzed thermal spray Ti, used for impressed current cathodic protection of reinforced concrete structures, are reviewed. considerations include spray parameters, atomizing gases, spray rate, and costs, as well as physical properties, composition, and structure, comparisons of the effect of electrochemical aging on voltage requirements, bond strength, coating resistivity, water permeability, and anode-concrete interfacial chemistry are included. C1 US DOE, Albany Res Ctr, Albany, OR 97321 USA. Oregon Dept Transportat, Salem, OR 97310 USA. RP Covino, BS (reprint author), US DOE, Albany Res Ctr, 1450 Queen Ave SW, Albany, OR 97321 USA. RI Holcomb, Gordon/G-9070-2013 OI Holcomb, Gordon/0000-0003-3542-5319 NR 7 TC 5 Z9 6 U1 0 U2 1 PU NATL ASSN CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 USA SN 0094-1492 J9 MATER PERFORMANCE JI Mater. Perform. PD JAN PY 1999 VL 38 IS 1 BP 27 EP 33 PG 7 WC Materials Science, Characterization & Testing SC Materials Science GA 156VC UT WOS:000078021900021 ER PT S AU Chung, JS Tamura, N Ice, GE Larson, BC Budai, JD AF Chung, JS Tamura, N Ice, GE Larson, BC Budai, JD BE Volkert, CA Verbuggen, AH Brown, DD TI X-ray microbeam measurement of local texture and strain in metals SO MATERIALS RELIABILITY IN MICROELECTRONICS IX SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Materials Reliability in Microelectronics IX Symposium at the 1999 MRS Spring Meeting CY APR 06-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Adv Micro Devices AB Synchrotron x-ray sources provide high-brilliance beams that can be focused to submicron sizes with Fresnel zone-plate and x-ray mirror optics. With these intense, tunable or broad-bandpass x-ray microbeams, it is now possible to study texture and strain distributions in surfaces, and in buried or encapsulated thin films. The full strain tensor and local texture can be determined by measuring the unit cell parameters of strained material. With monochromatic or tunable radiation, at least three independent reflections are needed to determine the orientation and unit cell parameters of an unknown crystal. With broad-bandpass or white radiation, at least four reflections and one measured energy are required to determine the orientation and the unit cell parameters of an unknown crystal. Routine measurement of local texture and strain is made possible by automatic indexing of the Laue reflections combined with precision calibration of the monochromator-focusing mirrors-CCD detector system. Methods used in implementing these techniques on the MHATT-CAT beam line at the Advanced Photon Source will be discussed. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Chung, JS (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 11 TC 17 Z9 17 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-470-X J9 MATER RES SOC SYMP P PY 1999 VL 563 BP 169 EP 174 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Engineering; Materials Science GA BN91M UT WOS:000083461000027 ER PT S AU Tamura, N Chung, JS Ice, GE Larson, BC Budai, JD Tischler, JZ Yoon, M Williams, EL Lowe, WP AF Tamura, N Chung, JS Ice, GE Larson, BC Budai, JD Tischler, JZ Yoon, M Williams, EL Lowe, WP BE Volkert, CA Verbuggen, AH Brown, DD TI Strain and texture in Al-interconnect wires measured by x-ray microbeam diffraction SO MATERIALS RELIABILITY IN MICROELECTRONICS IX SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Materials Reliability in Microelectronics IX Symposium at the 1999 MRS Spring Meeting CY APR 06-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Adv Micro Devices ID STRESS; LINES; ELECTROMIGRATION; MICRODIFFRACTION AB The local strain and texture in Al interconnect wires have been investigated using white and monochromatic re-ray microbeams on the MHATTCAT undulator beam line at the Advanced Photon Source. Intergrain and intragrain orientations were obtained with similar to 0.01 degrees sensitivity using white bears measurements on wide Al pads (similar to 100 mu m) and thin (2 mu m) Al wires. Orientation changes of up to 1 degrees were found within individual grains of the (111) textured Al interconnects. Deviatoric strain measurements indicate small intragranular strain variations, but intergranular strain variations were found to be quite large. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Tamura, N (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 7 TC 28 Z9 28 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-470-X J9 MATER RES SOC SYMP P PY 1999 VL 563 BP 175 EP 180 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Engineering; Materials Science GA BN91M UT WOS:000083461000028 ER PT S AU Bliss, DE Adams, DP Cameron, SM Luk, TS AF Bliss, DE Adams, DP Cameron, SM Luk, TS BE Heuer, AH Jacobs, SJ TI Laser machining with ultrashort pulses: Effects of pulse-width, frequency and energy SO MATERIALS SCIENCE OF MICROELECTROMECHANICAL SYSTEMS (MEMS) DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium AA on Materials Science of Microelectromechanical Systems (MEMS) Devices at the 1998 MRS Fall Meeting CY DEC 01-02, 1998 CL BOSTON, MA SP Mat Res Soc ID ABLATION AB The benefits of short pulse (femtosecond) laser machining over conventional nanosecond lasers have been well demonstrated: higher aspect ratio features with smaller remelt zones and less recast material. However, shock induced defects can degrade the mechanical, electrical and optical properties of the remaining material, especially in brittle materials. Our focus is to reduce the amount of defects created while maintaining the machining advantages of using ultra-short pulses. Utilizing a chirped pulse amplified Ti:Sapphire laser with a pulse energy of 1 mJ and a pulsewidth of 120 fs we investigated the effects of pulsewidth, laser frequency and pulse energy on the controlled micro-ablation of Kovar and silicon films. Hole morphology and diameter were characterized by SEM. Hole depth was measured by laser profilometry. Hole volumes were determined by a combination of profilometry and SEM to determine the rate of material removal. The ablation thresholds for both Kovar and Si are between 200-300 mJcm(-2). C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Bliss, DE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 2 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-452-1 J9 MATER RES SOC SYMP P PY 1999 VL 546 BP 81 EP 84 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BP16Q UT WOS:000084260700012 ER PT S AU Ager, JW Monteiro, OR Brown, IG Follstaedt, DM Knapp, JA Dugger, MT Christenson, TR AF Ager, JW Monteiro, OR Brown, IG Follstaedt, DM Knapp, JA Dugger, MT Christenson, TR BE Heuer, AH Jacobs, SJ TI Performance of ultra hard carbon wear coatings on microgears fabricated by LIGA SO MATERIALS SCIENCE OF MICROELECTROMECHANICAL SYSTEMS (MEMS) DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium AA on Materials Science of Microelectromechanical Systems (MEMS) Devices at the 1998 MRS Fall Meeting CY DEC 01-02, 1998 CL BOSTON, MA SP Mat Res Soc ID DEPOSITION; FILMS AB Stiction and friction are of concern for the reliable, long-term application of Ni-alloy micromachines. We have found that the application of a 30 - 70 nm hard carbon coating produces a significant reduction in the friction coefficient and wear rate of electroformed Ni substrates in reciprocating sliding contact under simulated MEMS operating conditions. To evaluate the performance of coated components, a series of 70-mu m-thick microgears ranging in diameter from 0.2 to 2.2 mm were fabricated from electroformed Ni via standard LIGA processes and fixtured on posts in preparation for the coating procedure. A pulsed vacuum-arc deposition process was used to deposit a carbon coating on the gears with the plasma incident at a shadow angle to the gears' top surface. A sample bias of -2 keV was used in order to produce a coating with relatively low stress and good adhesion while maintaining high hardness. This coating process is known to be somewhat comformal to the component surfaces. The coating uniformity, particularly in the high-aspect-ratio areas between the gear teeth, was evaluated with micro-Raman spectroscopy. It is shown that the coating can be applied uniformly on the top gear surface. Between the gear teeth the coating was the same thickness as on top of the gear down to a point 50 mu m below the top surface. Below that point (i.e. between 50 and 70 mu m), the coating thickness is somewhat thinner, but is still present. These results demonstrate that it is possible to a deposit hard carbon coating on microgears to reduce friction and wear in micromachines. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ager, JW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. OI Ager, Joel/0000-0001-9334-9751 NR 6 TC 1 Z9 1 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-452-1 J9 MATER RES SOC SYMP P PY 1999 VL 546 BP 115 EP 120 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BP16Q UT WOS:000084260700018 ER PT S AU Buchheit, TE Christenson, TR Schmale, DT Lavan, DA AF Buchheit, TE Christenson, TR Schmale, DT Lavan, DA BE Heuer, AH Jacobs, SJ TI Understanding and tailoring the mechanical properties of LIGA fabricated materials SO MATERIALS SCIENCE OF MICROELECTROMECHANICAL SYSTEMS (MEMS) DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium AA on Materials Science of Microelectromechanical Systems (MEMS) Devices at the 1998 MRS Fall Meeting CY DEC 01-02, 1998 CL BOSTON, MA SP Mat Res Soc AB LIGA fabricated materials and components exhibit several processing issues affecting their metallurgical and mechanical properties, potentially limiting their usefulness for MEMS applications. For example, LIGA processing by metal electrodeposition is very sensitive to deposition conditions which causes significant processing lot variations of mechanical and metallurgical properties. Furthermore, the process produces a material with a highly textured lenticular microstructural morphology suggesting an anisotropic material response. Understanding and controlling out-of-plane anisotropy is desirable for LIGA components designed for out-of-plane flexures. Previous work by the current authors [6] focussed on results from a miniature servo-hydraulic mechanical test frame constructed for characterizing LIGA materials. Those results demonstrated microstructural and mechanical properties dependencies with plating bath current density in LIGA fabricated nickel (LIGA Ni). This presentation builds on that work and fosters a methodology for controlling the properties of LIGA fabricated materials through processing. New results include measurement of mechanical properties of LIGA fabricated copper (LIGA Cu), out-of-plane and localized mechanical property measurements using compression testing and nanoindentation of LIGA Ni and LIGA Cu. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Buchheit, TE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI LaVan, David/C-3943-2012 OI LaVan, David/0000-0002-1952-0028 NR 7 TC 11 Z9 11 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-452-1 J9 MATER RES SOC SYMP P PY 1999 VL 546 BP 121 EP 126 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BP16Q UT WOS:000084260700019 ER PT S AU Christenson, TR Buchheit, TE Schmale, DT AF Christenson, TR Buchheit, TE Schmale, DT BE Heuer, AH Jacobs, SJ TI Torsion testing of diffusion bonded LIGA formed nickel SO MATERIALS SCIENCE OF MICROELECTROMECHANICAL SYSTEMS (MEMS) DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium AA on Materials Science of Microelectromechanical Systems (MEMS) Devices at the 1998 MRS Fall Meeting CY DEC 01-02, 1998 CL BOSTON, MA SP Mat Res Soc ID X-RAY-LITHOGRAPHY; DEEP AB A test technique has been devised which is suitable for the testing of the bond strength of batch diffusion bonded LIGA or DXRL defined structures. The method uses a torsion tester constructed with the aid of LIGA fabrication and distributed torsion specimens which also make use of the high aspect ratio nature of DXRL based processing. Measurements reveal achieved bond stengths of 130 MPa between electroplated nickel with a bond temperature of 450 degrees C at 7 ksi pressure which is a sufficiently low temperature to avoid mechanical strength degradation. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Christenson, TR (reprint author), Sandia Natl Labs, POB 5800,MS-0329, Albuquerque, NM 87185 USA. NR 8 TC 4 Z9 4 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-452-1 J9 MATER RES SOC SYMP P PY 1999 VL 546 BP 127 EP 132 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BP16Q UT WOS:000084260700020 ER PT S AU Garino, TJ Christenson, T Venturini, E AF Garino, TJ Christenson, T Venturini, E BE Heuer, AH Jacobs, SJ TI Fabrication of MEMS devices by powder-filling into DXRL-formed molds SO MATERIALS SCIENCE OF MICROELECTROMECHANICAL SYSTEMS (MEMS) DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium AA on Materials Science of Microelectromechanical Systems (MEMS) Devices at the 1998 MRS Fall Meeting CY DEC 01-02, 1998 CL BOSTON, MA SP Mat Res Soc AB We have developed a variety of processes for fabricating components for micro devices based on deep x-ray lithography (DXRL). Although the techniques are applicable to many materials, we have demonstrated them using hard (Nd2Fe14B) and soft (Ni-Zn ferrite) magnetic materials because of the importance of these materials in magnetic micro-actuators and other devices and because of the difficulty fabricating them by other means. The simplest technique involves pressing a mixture of magnetic powder and a binder into a DXRL-formed mold. In the second technique, powder is pressed into the mold and then sintered to densify. The other two processes involve pressing at high temperature either powder or a dense bulk material into a ceramic mold that was previously made using a DXRL mold. These techniques allow arbitrary 2-dimensional shapes to be made 10 to 1000 mu m thick with in-plane dimensions as small as 50 mu m and dimensional tolerances in the micron range. Bonded isotropic Nd2Fe14B micro-magnets made by these processes had an energy product of 7 MGOe. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Garino, TJ (reprint author), Sandia Natl Labs, MS-1411, Albuquerque, NM 87185 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-452-1 J9 MATER RES SOC SYMP P PY 1999 VL 546 BP 195 EP 200 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BP16Q UT WOS:000084260700031 ER PT S AU Adams, DP Benavides, GL Vasile, MJ AF Adams, DP Benavides, GL Vasile, MJ BE Heuer, AH Jacobs, SJ TI Micrometer-scale machining of metals and polymers enabled by focused ion beam sputtering SO MATERIALS SCIENCE OF MICROELECTROMECHANICAL SYSTEMS (MEMS) DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium AA on Materials Science of Microelectromechanical Systems (MEMS) Devices at the 1998 MRS Fall Meeting CY DEC 01-02, 1998 CL BOSTON, MA SP Mat Res Soc ID MICROFABRICATION; MICROSCOPY AB This work combines focused ion beam sputtering and ultra-precision machining for microfabrication of metal alloys and polymers. Specifically, micro-end mills are made by Ga ion beam sputtering of a cylindrical tool shank. Using an ion energy of 20keV, the focused beam defines the tool cutting edges that have submicrometer radii of curvature. We demonstrate 25 mu m diameter micromilling tools having 2, 4 and 5 cutting edges. These tools fabricate fine channels, 26-28 microns wide, in 6061 aluminum, brass, and polymethyl methacrylate. Micro-tools are structurally robust and operate for more than 5 hours without fracture. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Adams, DP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 12 TC 3 Z9 3 U1 2 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-452-1 J9 MATER RES SOC SYMP P PY 1999 VL 546 BP 201 EP 205 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BP16Q UT WOS:000084260700032 ER PT J AU Marsden, JE Shkoller, S AF Marsden, JE Shkoller, S TI Multisymplectic geometry, covariant Hamiltonians, and water waves SO MATHEMATICAL PROCEEDINGS OF THE CAMBRIDGE PHILOSOPHICAL SOCIETY LA English DT Article AB This paper concerns the development and application of the multisymplectic Lagrangian and Hamiltonian formalism for nonlinear partial differential equations. This theory generalizes and unifies the classical Hamiltonian formalism of particle mechanics as well as the many pre-symplectic 8-forms used by Bridges. In this theory, solutions of a partial differential equation are sections of a fibre bundle Y over a base manifold X of dimension n+1, typically taken to be spacetime. Given a connection on Y, a covariant Hamiltonian density H is then intrinsically defined on the primary constraint manifold P-L, the image of the multisymplectic version of the Legendre transformation. One views P-L as a subbundle of J(1)(Y)(star), the affine dual of J(1)(Y), the first jet bundle of Y. A canonical multisymplectic (n+2)-form Omega(H) is then defined, from which we obtain a multisymplectic Hamiltonian system of differential equations that is equivalent to both the original partial differential equation as well as the Euler-Lagrange equations of the corresponding Lagrangian. Furthermore, we show that the n+1 2-forms omega((mu)) defined by Bridges are a particular coordinate representation for a single multisymplectic (n+2)-form and, in the presence of symmetries, can be assembled into Omega(H). A generalized Hamiltonian Noether theory is then constructed which relates the action of the symmetry groups lifted to P-L with the conservation laws of the system. These conservation laws are defined by our generalized Noether's theorem which recovers the vanishing of the divergence of the vector of n+1. distinct momentum mappings defined by Bridges and, when applied to water waves, recovers Whitham's conservation of wave action. In our view, the multisymplectic structure provides the natural setting for studying dispersive wave propagation problems, particularly the instability of water waves, as discovered by Bridges. After developing the theory, we show its utility in the study of periodic pattern formation and wave instability. C1 CALTECH, Pasadena, CA 91125 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Marsden, JE (reprint author), CALTECH, Pasadena, CA 91125 USA. EM marsden@cds.caltech.edu; shkoller@cnls.lanl.gov NR 10 TC 74 Z9 76 U1 0 U2 6 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0305-0041 J9 MATH PROC CAMBRIDGE JI Math. Proc. Camb. Philos. Soc. PD JAN PY 1999 VL 125 BP 553 EP 575 DI 10.1017/S0305004198002953 PN 3 PG 23 WC Mathematics SC Mathematics GA 172DC UT WOS:000078906500013 ER PT J AU Ferguson, HRP Bailey, DH Arno, S AF Ferguson, HRP Bailey, DH Arno, S TI Analysis of PSLQ, an integer relation finding algorithm SO MATHEMATICS OF COMPUTATION LA English DT Article DE Euclidean algorithm; integer relation finding algorithm; Gaussian integer; Hamiltonian integer; polynomial time ID LATTICE BASIS REDUCTION; IMPROVED PRACTICAL ALGORITHMS; SUBSET SUM PROBLEMS; NUMBERS AB Let K be either the real, complex, or quaternion number system and let O(K) be the corresponding integers. Let x = (x(1),..., x(n)) be a vector in K-n. The vector x has an integer relation if there exists a vector m = (m(1),..., m(n)) is an element of O(K)(n), m not equal 0, such that m(1)x(1) + m(2)x(2) + ... + m(n)x(n) = 0. In this paper we define the parameterized integer relation construction algorithm PSLQ(tau), where the parameter tau can be freely chosen in a certain interval. Beginning with an arbitrary vector x = (x(1),..., x(n)) is an element of K-n, iterations of PSLQ(tau) will produce lower bounds on the norm of any possible relation for x. Thus PSLQ(tau) can be used to prove that there are no relations for a of norm less than a given size. Let M-x be the smallest norm of any relation for a. For the real and complex case and each fixed parameter tau in a certain interval, we prove that PSLQ( tau) constructs a relation in less than O(n(3) + n(2) log M-x) iterations. C1 Ctr Comp Sci, Bowie, MD 20715 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ferguson, HRP (reprint author), Ctr Comp Sci, 17100 Sci Dr, Bowie, MD 20715 USA. EM helamanf@super.org; dhb@nersc.gov; arno@super.org NR 42 TC 75 Z9 79 U1 0 U2 1 PU AMER MATHEMATICAL SOC PI PROVIDENCE PA 201 CHARLES ST, PROVIDENCE, RI 02940-2213 USA SN 0025-5718 EI 1088-6842 J9 MATH COMPUT JI Math. Comput. PD JAN PY 1999 VL 68 IS 225 BP 351 EP 369 DI 10.1090/S0025-5718-99-00995-3 PG 19 WC Mathematics, Applied SC Mathematics GA 149BQ UT WOS:000077585600020 ER PT B AU Silver, RN AF Silver, RN BE VonderLinden, W Dose, V Fischer, R Preuss, R TI Quantum entropy regularization SO MAXIMUM ENTROPY AND BAYESIAN METHODS SE FUNDAMENTAL THEORIES OF PHYSICS LA English DT Proceedings Paper CT 18th International Workshop on Maximum Entropy and Bayesian Methods of Statistical Analysis CY JUL 27-31, 1998 CL GARCHING, GERMANY SP Deutsch Phys Gesell, Max Planck Inst Plasmaphys DE quantum entropy; maximum entropy; density estimation; inverse problems; smoothing; Fourier methods; non-parametric function estimation ID DENSITIES; STATES AB By generalizing from classical entropy to quantum entropy, the maximum entropy method may be applied to non-parametric function estimation problems requiring smoothing, such as density estimation. I describe the use of quantum entropy as a regularization functional. Then I introduce a maximum Fourier entropy model whose behavior is similar to maximum quantum entropy, but which is easier to calculate and interpret. C1 Univ Calif Los Alamos Natl Lab, MS B262, Los Alamos, NM 87545 USA. RP Silver, RN (reprint author), Univ Calif Los Alamos Natl Lab, MS B262, POB 1663, Los Alamos, NM 87545 USA. NR 5 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5766-3 J9 FUND THEOR PY 1999 VL 105 BP 91 EP 98 PG 8 WC Physics, Mathematical SC Physics GA BP62H UT WOS:000085708600009 ER PT B AU Hanson, KM Cunningham, GS AF Hanson, KM Cunningham, GS BE VonderLinden, W Dose, V Fischer, R Preuss, R TI Operation of the Bayes Inference Engine SO MAXIMUM ENTROPY AND BAYESIAN METHODS SE Fundamental Theories of Physics LA English DT Proceedings Paper CT 18th International Workshop on Maximum Entropy and Bayesian Methods of Statistical Analysis CY JUL 27-31, 1998 CL GARCHING, GERMANY SP Deutsch Phys Gesell, Max Planck Inst Plasmaphys DE Bayesian analysis; MAP estimator; uncertainty estimation; radiographic modeling; Markov chain Monte Carlo; adjoint differentiation; object oriented design ID RECONSTRUCTIONS; MODELS AB We have developed a computer application, called the Bayes Inference Engine, to enable us to make inferences about models of a physical object from radiographs taken of it. In the BIE calculational models are represented by a dataflow diagram that can be manipulated by the analyst in a graphical-programming environment. We demonstrate the operation of the BIE in terms of examples of two-dimensional tomographic reconstruction including: uncertainty estimation. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hanson, KM (reprint author), Los Alamos Natl Lab, MS P940, Los Alamos, NM 87545 USA. EM kmh@lanl.gov; cunning@lanl.gov RI Cunningham, Gregory/F-1017-2011 OI Cunningham, Gregory/0000-0001-8819-4345 NR 25 TC 2 Z9 3 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5766-3 J9 FUND THEOR PHYS PY 1999 VL 105 BP 309 EP 318 PG 10 WC Physics, Mathematical SC Physics GA BP62H UT WOS:000085708600030 ER PT J AU Tura, A Sarti, A Gaens, T Lamberti, C AF Tura, A Sarti, A Gaens, T Lamberti, C TI Regularization of blood motion fields by modified Navier-Stokes equations SO MEDICAL ENGINEERING & PHYSICS LA English DT Article DE regularization; Navier-Stokes equations; ventricular dynamics; velocity field AB A technique for the regularization of incompressible fluid motion fields based on the use of modified Navier-Stokes equations is presented. It is shown that the technique belongs to the class of Tikhonov-type regularization methods. The technique was applied to an analytically known fluid-dynamic problem (Couette flow). Noisy and scattered versions of the analytical velocity field were generated, and the accuracy in reconstructing the analytical field was evaluated. It was found that accuracy depends on the value of a regularization parameter, and its optimal value depends on the entity of noise and scattering. When the optimal value is selected, the accuracy of the regularization technique is excellent, even for consistent noise and scattering levels. The technique was finally applied to echocardiographic data in order to estimate the blood velocity field within the left ventricle. (C) 1999 IPEM. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Bologna, DEIS, Biomed Engn Lab, I-40136 Bologna, Italy. Univ Calif Berkeley, LBNL, Berkeley, CA 94720 USA. Katholieke Univ Leuven, ESAT, Med Imaging Res Lab, Louvain, Belgium. RP Tura, A (reprint author), Univ Bologna, DEIS, Biomed Engn Lab, Viale Risorgimento 2, I-40136 Bologna, Italy. OI LAMBERTI, CLAUDIO/0000-0002-0039-1369 NR 20 TC 4 Z9 4 U1 3 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1350-4533 J9 MED ENG PHYS JI Med. Eng. Phys. PD JAN PY 1999 VL 21 IS 1 BP 27 EP 36 DI 10.1016/S1350-4533(99)00019-3 PG 10 WC Engineering, Biomedical SC Engineering GA 184QL UT WOS:000079624400004 PM 10220134 ER PT S AU Schmidt, DM George, JS Wood, CC AF Schmidt, DM George, JS Wood, CC BE Hanson, KM TI Bayesian inference for neural electromagnetic source localization: Analysis of MEG visual evoked activity SO MEDICAL IMAGING 1999: IMAGE PROCESSING, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Medical Imaging 1999 Conference - Image Processing CY FEB 22-25, 1999 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers, Amer Assoc Physicists Med, Amer Physiol Soc, FDA Ctr Devices & Radiol Hlth, Soc Imaging Sci & Technol, Natl Elect Manufacturers Assoc, Diagnost Imaging & Therapy Syst Div, Radiol Soc N Amer, Soc Comp Applicat Radiol DE MEG; inverse problem; MCMC ID HUMAN-BRAIN; INVERSE PROBLEM; MAGNETOENCEPHALOGRAPHY; CORTEX AB We have developed a Bayesian approach to the analysis of neural electromagnetic (MEG/EEG) data that can incorporate or fuse information from other imaging modalities and addresses the ill-posed inverse problem by sampling the many different solutions which could have produced the given data. From these samples one can draw probabilistic inferences about regions of activation. Our source model assumes a variable number of variable size cortical regions of stimulus-correlated activity. An active region consists of locations on the cortical surface, within a sphere centered on some location in cortex. The number and radii of active regions can vary to defined maximum values. The goal of the analysis is to determine the posterior probability distribution for the set of parameters that govern the number, location, and extent of active regions. Markov Chain Monte Carlo is used to generate a large sample of sets of parameters distributed according to the posterior distribution. This sample is representative of the many different source distributions that could account for given data, and allows identification of probable (i.e, consistent) features across solutions. Examples of the use of this analysis technique with both simulated and empirical MEG data are presented. C1 Univ Calif Los Alamos Natl Lab, Biophys Grp, Los Alamos, NM 87545 USA. RP Schmidt, DM (reprint author), Univ Calif Los Alamos Natl Lab, Biophys Grp, POB 1663, Los Alamos, NM 87545 USA. NR 27 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3133-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3661 BP 408 EP 419 DI 10.1117/12.348596 PN 1&2 PG 12 WC Engineering, Biomedical; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BN14N UT WOS:000080862400039 ER PT S AU Cunningham, GS Lehovich, A Hanson, KM AF Cunningham, GS Lehovich, A Hanson, KM BE Hanson, KM TI Bayesian estimation of regularization parameters for deformable surface models SO MEDICAL IMAGING 1999: IMAGE PROCESSING, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Medical Imaging 1999 Conference - Image Processing CY FEB 22-25, 1999 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers, Amer Assoc Physicists Med, Amer Physiol Soc, FDA Ctr Devices & Radiol Hlth, Soc Imaging Sci & Technol, Natl Elect Manufacturers Assoc, Diagnost Imaging & Therapy Syst Div, Radiol Soc N Amer, Soc Comp Applicat Radiol DE Bayesian inference; hyperparameters; deformable models; dynamic cardiac SPECT ID TOMOGRAPHIC RECONSTRUCTION AB In this article we build on our past attempts to reconstruct a 3D, time-varying bolus of radiotracer from first-pass data obtained by the dynamic SPECT imager, FASTSPECT, built by the University of Arizona. The object imaged is a CardioWest total artificial heart. The bolus is entirely contained in one ventricle and its associated inlet and outlet tubes. The model for the radiotracer distribution at a given time is a closed surface parameterized by 482 vertices that are connected to make 960 triangles, with nonuniform intensity variations of radiotracer allowed inside the surface on a voxel-to-voxel basis. The total curvature of the surface is minimized through the use of a weighted prior in the Bayesian framework, as is the weighted norm of the gradient of the voxellated grid. MAP estimates for the vertices, interior intensity voxels and background count level are produced. The strength of the priors, or hyperparameters, are determined by maximizing the probability of the data given the hyperparameters, called the evidence. The evidence is calculated by first assuming that the posterior is approximately normal in the values of the vertices and voxels, and then by evaluating the integral of the multidimensional normal distribution. This integral (which requires evaluating the determinant of a covariance matrix) is computed by applying a recent algorithm from Bai et. al. that calculates the needed determinant efficiently. We demonstrate that the radiotracer is highly inhomogenous in early time frames, as suspected in earlier reconstruction attempts that assumed a uniform intensity of radiotracer within the closed surface, and that the optimal choice of hyperparameters is substantially different for different time frames. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Cunningham, GS (reprint author), Univ Calif Los Alamos Natl Lab, MS P940, Los Alamos, NM 87544 USA. RI Cunningham, Gregory/F-1017-2011 OI Cunningham, Gregory/0000-0001-8819-4345 NR 13 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3133-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3661 BP 562 EP 573 DI 10.1117/12.348612 PN 1&2 PG 12 WC Engineering, Biomedical; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BN14N UT WOS:000080862400054 ER PT S AU Sari-Sarraf, H Gleason, SS Nishikawa, RM AF Sari-Sarraf, H Gleason, SS Nishikawa, RM BE Hanson, KM TI Front-end data reduction in computer-aided diagnosis of mammograms: A pilot study SO MEDICAL IMAGING 1999: IMAGE PROCESSING, PTS 1 AND 2 SE Proceedings of SPIE LA English DT Proceedings Paper CT Medical Imaging 1999 Conference - Image Processing CY FEB 22-25, 1999 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers, Amer Assoc Physicists Med, Amer Physiol Soc, FDA Ctr Devices & Radiol Hlth, Soc Imaging Sci & Technol, Natl Elect Manufacturers Assoc, Diagnost Imaging & Therapy Syst Div, Radiol Soc N Amer, Soc Comp Applicat Radiol DE computer-aided diagnosis; fractal encoding; microcalcification detection; data reduction; data throughput; breast cancer; computer vision ID CLUSTERED MICROCALCIFICATIONS AB This paper presents the results of a pilot study whose primary objective was to further substantiate the efficacy of front-end data reduction in computer-aided diagnosis (CAD) of mammograms. This concept is realized by a preprocessing module that can be utilized at the front-end of most mammographic CAD systems. Based on fractal encoding, this module takes a mammographic image as its input and generates, as its output, a collection of subregions called focus-of-attention regions (FARs). These FARs contain all structures in the input image that appear to be different from the normal background tissue. Subsequently, the CAD systems need only to process the presented FARs, rather than the entire input image. This accomplishes two objectives simultaneously: (1) an increase in throughput via a reduction in the input data, and (2) a reduction in false detections by limiting the scope of the detection algorithms to FARs only. The pilot study consisted of using the preprocessing module to analyze 80 mammographic images. The results were an average data reduction of 83% over all 80 images and an average false detection reduction of 86%. Furthermore, out of a total of 507 marked microcalcifications, 467 fell within FARs, representing a coverage rate of 92%. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. EM sarisarrafh@ornl.gov OI Nishikawa, Robert/0000-0001-7720-9951 NR 8 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3133-8 J9 PROC SPIE PY 1999 VL 3661 BP 1535 EP 1543 DI 10.1117/12.348556 PN 1&2 PG 9 WC Engineering, Biomedical; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BN14N UT WOS:000080862400158 ER PT S AU Schmidt, DM George, JS Wood, CC AF Schmidt, DM George, JS Wood, CC BE Chen, CT Clough, AV TI Bayesian analysis of MEG visual evoked responses SO MEDICAL IMAGING 1999: PHYSIOLOGY AND FUNCTION FROM MULTIDIMENSIONAL IMAGES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Medical Imaging 1999 Conference CY FEB 21-25, 1999 CL SAN DIEGO, CA SP SPIE, Amer Assoc Physicists Med, Amer Physiol Soc, FDA Ctr Devices & Radiol Hlth, Soc Imaging Sci & Technol, Natl Elect Mfg Assoc/Diagnost Imaging & Therapy Syst Div, Radiol Soc N Amer, Soc Comp Applicat Radiol DE MEG; inverse problem; MCMC ID HUMAN-BRAIN; LOCALIZATION; MAGNETOENCEPHALOGRAPHY AB We have developed a method for analyzing neural electromagnetic data that allows probabilistic inferences to be drawn about regions of activation. The method involves the generation of a large number of possible solutions which both fit the data and prior expectations about the nature of probable solutions made explicit by a Bayesian formalism. In addition, we have introduced a model for the current distributions that produce MEG (and EEG) data that allows extended regions of activity, and can easily incorporate prior information such as anatomical constraints from MRI. To evaluate the feasibility and utility of the Bayesian approach with actual data, we analyzed MEG data from a visual evoked response experiment. We compared Bayesian analyses of MEG responses to visual stimuli in the left and right visual fields, in order to examine the sensitivity of the method to detect known features of human visual cortex organization. We also examined the changing pattern of cortical activation as a function of time. C1 Univ Calif Los Alamos Natl Lab, Biophys Grp, Los Alamos, NM 87545 USA. RP Schmidt, DM (reprint author), Univ Calif Los Alamos Natl Lab, Biophys Grp, POB 1663, Los Alamos, NM 87545 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3132-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3660 BP 2 EP 9 DI 10.1117/12.349576 PG 8 WC Engineering, Biomedical; Optics; Physiology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Optics; Physiology; Radiology, Nuclear Medicine & Medical Imaging GA BN29K UT WOS:000081442700001 ER PT J AU Rivard, MJ Wierzbicki, JG Van den Heuvel, F Martin, RC McMahon, RR AF Rivard, MJ Wierzbicki, JG Van den Heuvel, F Martin, RC McMahon, RR TI Clinical brachytherapy with neutron emitting Cf-252 sources and adherence to AAPM TG-43 dosimetry protocol SO MEDICAL PHYSICS LA English DT Article DE californium; brachytherapy; Monte Carlo; neutron; dosimetry ID PHYSICS AB Using Monte Carlo methods, neutron dosimetry for Cf-252 Applicator Tube (AT) type medical sources available from Oak Ridge National Laboratory (ORNL) has for the first time been determined in terms of TG-43 formalism. This approach, as compared to previous "along-away" formalisms, demonstrates the relative angular independence of dose rate data, when the geometry factor has been removed. As the ORNL-made Cf-252 AT type sources are considerably physically larger than most clinical sources used today, the radial dose function increases for radii less than 3.0 mm due to breakdown of the line source model. A comparison of the Cf-252 neutron radial dose function with those for other medical sources revealed similarities with that from Cs-137. Differences with respect to previous Cf-252 AT source neutron dosimetry data generally increased at increasing distances. This was attributed to differences in the various Cf-252 AT source models and phantom compositions. The current status of Cf-252 medical source fabrication and calibration procedures at ORNL is presented. (C) 1999 American Association of Physicists in Medicine. [S0094-2405(99)00501-5]. C1 Wayne State Univ, Harper Hosp, Barbara Ann Karmanos Canc Inst, Dept Radiat Oncol, Detroit, MI 48201 USA. Oak Ridge Natl Lab, Div Chem Technol, Radiochemn Engn Dev Ctr, Oak Ridge, TN 37831 USA. RP Rivard, MJ (reprint author), Wayne State Univ, Harper Hosp, Barbara Ann Karmanos Canc Inst, Dept Radiat Oncol, Detroit, MI 48201 USA. RI Van den Heuvel, Frank/G-6992-2011 OI Van den Heuvel, Frank/0000-0001-9904-502X NR 34 TC 19 Z9 19 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD JAN PY 1999 VL 26 IS 1 BP 87 EP 96 DI 10.1118/1.598472 PG 10 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 159VP UT WOS:000078196000012 PM 9949403 ER PT S AU Fleming, JG Lin, SY AF Fleming, JG Lin, SY GP IEEE IEEE TI Fabrication and properties of 3-D polysilicon photonic lattices in the infrared SO MEMS '99: TWELFTH IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST SE PROCEEDINGS: IEEE MICRO ELECTRO MECHANICAL SYSTEMS WORKSHOP LA English DT Proceedings Paper CT 12th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 99) CY JAN 17-21, 1999 CL ORLANDO, FL SP IEEE Robot & Automat Soc ID BAND-GAP AB Three-dimensional photonic lattices have been fabricated in the infrared using a variety of advanced silicon processes. The structures display band gaps centered at 12 mu and 1.55 mu. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Fleming, JG (reprint author), Sandia Natl Labs, POB 5800,Org 1723,MS 1084, Albuquerque, NM 87185 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1084-6999 BN 0-7803-5195-9 J9 PROC IEEE MICR ELECT PY 1999 BP 366 EP 370 DI 10.1109/MEMSYS.1999.746856 PG 5 WC Automation & Control Systems; Engineering, Electrical & Electronic; Engineering, Mechanical; Optics SC Automation & Control Systems; Engineering; Optics GA BM43W UT WOS:000078743100065 ER PT S AU Christenson, TR Schmale, DT AF Christenson, TR Schmale, DT GP IEEE IEEE TI A batch wafer scale LIGA assembly and packaging technique via diffusion bonding SO MEMS '99: TWELFTH IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST SE PROCEEDINGS: IEEE MICRO ELECTRO MECHANICAL SYSTEMS WORKSHOP LA English DT Proceedings Paper CT 12th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 99) CY JAN 17-21, 1999 CL ORLANDO, FL SP IEEE Robot & Automat Soc ID LITHOGRAPHY AB A technique using diffusion bonding (or solid-state welding) has been used to achieve batch fabrication of two-level nickel LIGA structures. Interlayer alignment accuracy of less than 1 micron is achieved using press-fit gauge pins. A milli-scale torsion tester was built to measure the diffusion bond strength of LIGA formed specimens that has shown successful bonding at temperatures of 450 degrees C at 7 ksi pressure with resulting bond strength greater than 100 MPa. Extensions to this basic process to allow for additional layers and thereby more complex assemblies as well as commensurate packaging are discussed. C1 Sandia Natl Labs, Electromech Engn Dept, Albuquerque, NM 87185 USA. RP Christenson, TR (reprint author), Sandia Natl Labs, Electromech Engn Dept, POB 5800, Albuquerque, NM 87185 USA. NR 17 TC 4 Z9 4 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1084-6999 BN 0-7803-5195-9 J9 PROC IEEE MICR ELECT PY 1999 BP 476 EP 481 DI 10.1109/MEMSYS.1999.746875 PG 6 WC Automation & Control Systems; Engineering, Electrical & Electronic; Engineering, Mechanical; Optics SC Automation & Control Systems; Engineering; Optics GA BM43W UT WOS:000078743100084 ER PT S AU Fleming, JG Lin, SY AF Fleming, JG Lin, SY BE Lawton, RA Miller, WM Lin, G Ramesham, R TI 3-D silicon photonic lattices - cornerstone of an emerging photonics revolution SO MEMS RELIABILITY FOR CRITICAL AND SPACE APPLICATIONS SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on MEMS Reliability for Critical and Space Applications CY SEP 21-22, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Sand & Technol, Sandia Natl Labs, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliabil Engn Assoc Japan DE photonic lattice MEMS; infrared; photonic bandgap ID BAND-GAP; CRYSTAL; WAVELENGTHS AB Three-dimensional photonic lattices are engineered "materials" which are the photonic analogues of semiconductors. These structures were first proposed and demonstrated in the mid-to-late 1980's. However, due to fabrication difficulties, lattices active in the infrared are only just emerging, Wide ranges of structures and fabrication approaches have been investigated. The most promising approach for many potential applications is a diamond-like structure fabricated using silicon microprocessing techniques. This approach has enabled the fabrication of 3-D silicon photonic lattices active in the infrared. The structures display band gaps centered from 12 mu down to 1.55 mu. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Fleming, JG (reprint author), Sandia Natl Labs, Org 1723,MS 1084,POB 5800, Albuquerque, NM 87185 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3477-9 J9 PROC SPIE PY 1999 VL 3880 BP 9 EP 18 PG 10 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BP12V UT WOS:000084201200002 ER PT S AU Walraven, JA Headley, TJ Campbell, AN Tanner, DM AF Walraven, JA Headley, TJ Campbell, AN Tanner, DM BE Lawton, RA Miller, WM Lin, G Ramesham, R TI Failure analysis of worn surface micromachined microengines SO MEMS RELIABILITY FOR CRITICAL AND SPACE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on MEMS Reliability for Critical and Space Applications CY SEP 21-22, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Sand & Technol, Sandia Natl Labs, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliabil Engn Assoc Japan DE wear debris; scanning electron microscopy; transmission electron microscopy; focused ion beam; energy dispersive X-ray spectroscopy; electron energy loss spectroscopy; MEMS AB Failure analysis (FA) tools have been applied to analyze failing polysilicon microengines. These devices were stressed to failure under accelerated conditions in both oxidizing and non-oxidizing environments. The dominant failure mechanism of these microengines was identified as wear of rubbing surfaces. This often results in either seized microengines or microengines with broken pin joints. Analysis of these failed polysilicon devices found that wear debris was produced in both oxidizing and non-oxidizing environments. By varying the relative percent humidity (%RH), we observed an increase in the amount of wear debris with decreasing humidity. Plan view imaging using scanning electron microscopy revealed build-up of wear debris on the surface of microengines. Focused ion beam (FIB) cross sections revealed the location and build-up of wear debris within the microengine. Seized regions were also observed in the pin joint area using FIB processing. By using transmission electron microscopy in conjunction with energy dispersive x-ray spectroscopy (EDX) and electron energy loss spectroscopy (EELS), we were able to identify wear debris produced in low (1.8% RH), medium and high (39% RH) humidities. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Walraven, JA (reprint author), Sandia Natl Labs, POB 5800,MS 1081, Albuquerque, NM 87185 USA. NR 14 TC 9 Z9 10 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3477-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3880 BP 30 EP 39 DI 10.1117/12.359369 PG 10 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BP12V UT WOS:000084201200004 ER PT S AU LaVan, DA Buchheit, TE AF LaVan, DA Buchheit, TE BE Lawton, RA Miller, WM Lin, G Ramesham, R TI Strength of polysilicon for MEMS devices SO MEMS RELIABILITY FOR CRITICAL AND SPACE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on MEMS Reliability for Critical and Space Applications CY SEP 21-22, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Sand & Technol, Sandia Natl Labs, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliabil Engn Assoc Japan DE polysilicon; strength; Weibull; distribution; tensile; nanoindenter; MEMS AB The safe, secure and reliable application of Microelectromechanical Systems (MEMS) devices requires knowledge about the distribution in material and mechanical properties of the small-scale structures. A new testing program at Sandia is quantifying the strength distribution using polysilicon samples that reflect the dimensions of critical MEMS components. The strength of polysilicon fabricated at Sandia's Microelectronic Development Laboratory was successfully measured using samples 2.5 microns thick, 1.7 microns wide with lengths between 15 and 25 microns. These tensile specimens have a freely moving hub on one end that anchors the sample to the silicon die and allows free rotation. Each sample is loaded in uniaxial tension by pulling laterally with a flat tipped diamond in a computer-controlled Nanoindenter. The stress-strain curve is calculated using the specimen cross section and gage length dimensions verified by measuring against a standard in the SEM. Fracture strength measurements grouped into three strength levels, which matched three observed failure modes. The samples in the highest strength group failed in the gage section, those in the moderate strength group failed at the gage section fillet and those in the lowest strength group failed at a dimple in the hub. With this technique, multiple tests can be programmed at one time and performed without operator assistance at a rate of 20-30 per day allowing the collection of significant populations of data. Since the new test geometry has been proven, the project is moving to test the distributions seen from real geometric features characteristic of MEMS, such as the effect of gage length, fracture toughness, bonding between layers, etch holes, dimples and shear of gear teeth. C1 Sandia Natl Labs, Mat Performance Reliabil & Aging Dept, Albuquerque, NM 87185 USA. RP LaVan, DA (reprint author), Sandia Natl Labs, Mat Performance Reliabil & Aging Dept, Albuquerque, NM 87185 USA. RI LaVan, David/C-3943-2012 OI LaVan, David/0000-0002-1952-0028 NR 12 TC 8 Z9 8 U1 1 U2 7 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3477-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3880 BP 40 EP 44 DI 10.1117/12.359366 PG 5 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BP12V UT WOS:000084201200005 ER PT S AU Smith, NF Eaton, WP Tanner, DM Allen, JJ AF Smith, NF Eaton, WP Tanner, DM Allen, JJ BE Lawton, RA Miller, WM Lin, G Ramesham, R TI Development of characterization tools for reliability testing of MicroElectroMechanical system actuators SO MEMS RELIABILITY FOR CRITICAL AND SPACE APPLICATIONS SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on MEMS Reliability for Critical and Space Applications CY SEP 21-22, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Sand & Technol, Sandia Natl Labs, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliabil Engn Assoc Japan DE MicroElectroMechanical Systems; MEMS actuator reliability; MEMS characterization; performance tools; image analysis ID SURFACE MICROMACHINED MICROENGINE AB Characterization tools have been developed to study the performance characteristics and reliability of surface micromachined actuators. These tools include 1) the ability to electrically stimulate or stress the actuator, 2) the capability to visually inspect the devices in operation, 3) a method for capturing operational information, and 4) a method to extract performance characteristics from the operational information. Additionally, a novel test structure has been developed to measure electrostatic forces developed by a comb drive actuator. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Smith, NF (reprint author), Sandia Natl Labs, POB 5800,MS 1081, Albuquerque, NM 87185 USA. EM smithnf@sandia.gov NR 11 TC 16 Z9 16 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3477-9 J9 PROC SPIE PY 1999 VL 3880 BP 156 EP 164 DI 10.1117/12.359365 PG 9 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BP12V UT WOS:000084201200019 ER EF