FN Thomson Reuters Web of Science™ VR 1.0 PT S AU Srinivas, S Salian, UA Jellinek, J AF Srinivas, S Salian, UA Jellinek, J BE Russo, N Salahub, DR TI Theoretical investigations of silver clusters and silver-ligand systems SO METAL-LIGAND INTERACTIONS IN CHEMISTRY, PHYSICS AND BIOLOGY SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT Conference of the NATO-Advances-Study-Institute on Metal-Ligand Interactions in Chemistry, Physics and Biology CY SEP 01-12, 1998 CL KETRARA, ITALY SP NATO, Sci Affairs Div, NATO, Adv Study Inst ID EFFECTIVE CORE POTENTIALS; TRANSITION-METAL ATOMS; DENSITY-FUNCTIONAL CALCULATIONS; CORRELATION-ENERGY; MOLECULAR CALCULATIONS; ELECTRONIC-STRUCTURE; POSITIVE-IONS; BASIS-SETS; CU-N; AG-N C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Srinivas, S (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 78 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-6125-3 J9 NATO ADV SCI I C-MAT PY 1999 VL 546 BP 295 EP 324 PG 30 WC Biochemistry & Molecular Biology; Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Biochemistry & Molecular Biology; Chemistry; Physics GA BR58H UT WOS:000166854500012 ER PT B AU Hay, BP AF Hay, BP BE Liddell, KC Chaiko, DJ TI The use of molecular mechanics in the design of metal ion sequestering agents SO METAL SEPARATION TECHNOLOGIES BEYOND 2000: INTEGRATING NOVEL CHEMISTRY WITH PROCESSING LA English DT Proceedings Paper CT 3rd Engineering-Foundation Conference on Processes and Reagents for Metal Separations - Metal Separation Technologies Beyond 2000 CY JUN 13-18, 1999 CL KAHUKU, HI SP United Engn Fdn, Natl Sci Fdn, Minerals Met & Mat Soc, Amer Inst Chem Engineers ID HOST-GUEST COMPLEXATION; MM3 FORCE-FIELD; COORDINATION CHEMISTRY; CROWN-ETHERS; SUPRAMOLECULAR CHEMISTRY; CONFORMATIONAL-ANALYSIS; STRUCTURAL CRITERIA; SELECTIVE LIGANDS; RATIONAL DESIGN; HEMISPHERANDS AB Complexation of a metal ion to a ligand often results in structural changes that introduce steric strain within the ligand. A design criterion for ligands that will complex metal ions more strongly is to choose ligand architecture that minimizes this strain. This paper describes how molecular mechanics models can be used to define the degree of ligand binding site organization in terms of strain energies associated with conformational reorganization and distortion of the binding conformer. This approach yields a method to predict how modifications to ligand structure will affect metal binding affinity. C1 Battelle Mem Inst, Pacific NW Labs, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Battelle Mem Inst, Pacific NW Labs, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. NR 37 TC 5 Z9 5 U1 0 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-442-9 PY 1999 BP 3 EP 13 PG 11 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical; Metallurgy & Metallurgical Engineering SC Chemistry; Engineering; Metallurgy & Metallurgical Engineering GA BN16X UT WOS:000080927700001 ER PT B AU Nash, KL Morss, LR Jensen, MP Appelman, EH Schmidt, MA Friedrich, SR Redko, M Hines, JJ AF Nash, KL Morss, LR Jensen, MP Appelman, EH Schmidt, MA Friedrich, SR Redko, M Hines, JJ BE Liddell, KC Chaiko, DJ TI Water-soluble organophosphorus reagents for mineralization of heavy metals SO METAL SEPARATION TECHNOLOGIES BEYOND 2000: INTEGRATING NOVEL CHEMISTRY WITH PROCESSING LA English DT Proceedings Paper CT 3rd Engineering-Foundation Conference on Processes and Reagents for Metal Separations - Metal Separation Technologies Beyond 2000 CY JUN 13-18, 1999 CL KAHUKU, HI SP United Engn Fdn, Natl Sci Fdn, Minerals Met & Mat Soc, Amer Inst Chem Engineers ID HYDROLYSIS; PHYTATE AB The control of solubility of waste actinide ions by conversion to highly insoluble mineral phases has been demonstrated in the laboratory. Actinide metal ions are removed from neutral pH solutions by a combined ion exchange-decomposition-mineralization process based on the application of the naturally-occurring hydrolytically unstable polyphosphate organic compound phytic acid. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Nash, KL (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Jensen, Mark/G-9131-2012 OI Jensen, Mark/0000-0003-4494-6693 NR 11 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 0-87339-442-9 PY 1999 BP 45 EP 56 PG 12 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical; Metallurgy & Metallurgical Engineering SC Chemistry; Engineering; Metallurgy & Metallurgical Engineering GA BN16X UT WOS:000080927700005 ER PT B AU Nyman, M Nenoff, TM AF Nyman, M Nenoff, TM BE Liddell, KC Chaiko, DJ TI Synthesis, characterization and ion exchange of new Na/Nb/M4+/O/H2O (M = Ti, Zr) phases SO METAL SEPARATION TECHNOLOGIES BEYOND 2000: INTEGRATING NOVEL CHEMISTRY WITH PROCESSING LA English DT Proceedings Paper CT 3rd Engineering-Foundation Conference on Processes and Reagents for Metal Separations - Metal Separation Technologies Beyond 2000 CY JUN 13-18, 1999 CL KAHUKU, HI SP United Engn Fdn, Natl Sci Fdn, Minerals Met & Mat Soc, Amer Inst Chem Engineers ID HYDROUS CRYSTALLINE SILICOTITANATES; LEVEL RADIOACTIVE-WASTE; TEMPERATURE SYNTHESIS; STRONTIUM; CESIUM; SODIUM; IMMOBILIZATION; SYNROC; REMOVAL; BEARING AB Due to the vast diversity of chemical media in which metal separations are executed, a wide range of ion separation materials are employed. This results in an ongoing effort to discover new phases with novel ion exchange properties. We present here the synthesis of a novel class of thermally and chemically stable microporous, niobate-based materials. ion exchange studies show these new phases are highly selective for Sr2+ and other bivalent metals. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Nyman, M (reprint author), Sandia Natl Labs, POB 5800,MS 0710, Albuquerque, NM 87185 USA. NR 47 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 0-87339-442-9 PY 1999 BP 59 EP 70 PG 12 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical; Metallurgy & Metallurgical Engineering SC Chemistry; Engineering; Metallurgy & Metallurgical Engineering GA BN16X UT WOS:000080927700006 ER PT B AU Mattigod, S Fryxell, GE Feng, X Liu, J AF Mattigod, S Fryxell, GE Feng, X Liu, J BE Liddell, KC Chaiko, DJ TI Self-assembled monolayers on mesoporous supports for metal separation SO METAL SEPARATION TECHNOLOGIES BEYOND 2000: INTEGRATING NOVEL CHEMISTRY WITH PROCESSING LA English DT Proceedings Paper CT 3rd Engineering-Foundation Conference on Processes and Reagents for Metal Separations - Metal Separation Technologies Beyond 2000 CY JUN 13-18, 1999 CL KAHUKU, HI SP United Engn Fdn, Natl Sci Fdn, Minerals Met & Mat Soc, Amer Inst Chem Engineers ID MOLECULAR-SIEVES; FUNCTIONALIZED MONOLAYERS; REMOVAL; MERCURY; SILICA; TEMPLATES; FILMS AB Self-assembled monolayers on mesoporous supports (SAMMS) have been developed for the removal of heavy metals and some transition metals. The thiol functional groups were assembled on the internal and external surfaces of mesoporous silica with a uniform pore size of about 55 Angstrom. The mesoporous supports provide high surface area (>900 m2/g) needed for high metal loading in chemical separation. Self-assembled monolayers of organic molecules bond to the ceramic substrate with prescribed densities, and with terminal functional groups for excellent molecular selectivity. The unique characteristics include: (1) High metal absorption capacity, up to 3.2 mmol/g of SAMMS. (2) Fast Hg-binding kinetics (reducing mercury concentration from 0.5 ppm to 0.5 ppb in less than 5 minutes). (3) High selectivity in the presence of a range of cations, anions, and organic species. (4) Applicability in both aqueous and non-aqueous solvents. (5) Flexibility in surface chemistry. The materials can be designed to adsorb heavy metals, transitional metals, and radionuclides. (6) Chemical stability, and potential for regeneration or waste storage. This paper discusses the results on mercury adsorption. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Mattigod, S (reprint author), Battelle Mem Inst, Pacific NW Labs, Box 999,P8-37, Richland, WA 99352 USA. NR 26 TC 9 Z9 9 U1 0 U2 3 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-442-9 PY 1999 BP 71 EP 79 PG 9 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical; Metallurgy & Metallurgical Engineering SC Chemistry; Engineering; Metallurgy & Metallurgical Engineering GA BN16X UT WOS:000080927700007 ER PT B AU Jarvinen, GD Smith, BF Robison, TW AF Jarvinen, GD Smith, BF Robison, TW BE Liddell, KC Chaiko, DJ TI Removal and recovery of metal ions from process and waste streams using polymer filtration SO METAL SEPARATION TECHNOLOGIES BEYOND 2000: INTEGRATING NOVEL CHEMISTRY WITH PROCESSING LA English DT Proceedings Paper CT 3rd Engineering-Foundation Conference on Processes and Reagents for Metal Separations - Metal Separation Technologies Beyond 2000 CY JUN 13-18, 1999 CL KAHUKU, HI SP United Engn Fdn, Natl Sci Fdn, Minerals Met & Mat Soc, Amer Inst Chem Engineers ID MEMBRANE FILTRATION; ULTRAFILTRATION; SEPARATION AB Polymer Filtration (PF) is an innovative, selective metal removal technology. Chelating, water-soluble polymers are used to selectively bind the desired metal ions and ultrafiltration is used to concentrate the polymer-metal complex producing a permeate with low levels of the targeted metal ion. When applied to the treatment of industrial metal-bearing aqueous process streams, the permeate water can often be reused within the process and the metal ions reclaimed. This technology is applicable to many types of industrial aqueous streams with widely varying chemistries. Application of PF to aqueous streams from nuclear materials processing and electroplating operations will be described. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Jarvinen, GD (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 12 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 0-87339-442-9 PY 1999 BP 131 EP 138 PG 8 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical; Metallurgy & Metallurgical Engineering SC Chemistry; Engineering; Metallurgy & Metallurgical Engineering GA BN16X UT WOS:000080927700012 ER PT B AU Chaiko, DJ Hatton, TA Zaslavsky, B AF Chaiko, DJ Hatton, TA Zaslavsky, B BE Liddell, KC Chaiko, DJ TI Aqueous biphasic systems for metal separations: A microcalorimetric analysis of polymer salt interactions SO METAL SEPARATION TECHNOLOGIES BEYOND 2000: INTEGRATING NOVEL CHEMISTRY WITH PROCESSING LA English DT Proceedings Paper CT 3rd Engineering-Foundation Conference on Processes and Reagents for Metal Separations - Metal Separation Technologies Beyond 2000 CY JUN 13-18, 1999 CL KAHUKU, HI SP United Engn Fdn, Natl Sci Fdn, Minerals Met & Mat Soc, Amer Inst Chem Engineers ID POLY(ETHYLENE OXIDE) AB Certain radionuclide ions (e.g., TcO4-) exhibit unusually strong Affinities toward the polymer-rich phase in aqueous biphase systems generated by combinations of salt solutions with polymers such as poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG). Thus, aqueous polymer phases could potentially be used to selectively extract these ions during pretreatment of radioactive tank wastes at Hanford. To help develop a fundamental understanding of the interactions between various ions and polymers in aqueous solution, interaction enthalpies between sodium perrhenate and a random copolymer of PEG and PPG (UCON-50) were measured by microcalorimetric titration. An entropy compensation effect was observed in this system in which changes in enthalpic interactions were balanced by entropy changes such that the interaction free energy remained constant and approximately equal to zero. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Chaiko, DJ (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Zaslavsky, Boris/0000-0003-0771-6696 NR 15 TC 2 Z9 2 U1 0 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-442-9 PY 1999 BP 167 EP 179 PG 13 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical; Metallurgy & Metallurgical Engineering SC Chemistry; Engineering; Metallurgy & Metallurgical Engineering GA BN16X UT WOS:000080927700016 ER PT B AU Lilga, MA Orth, RJ Sukamto, JPH AF Lilga, MA Orth, RJ Sukamto, JPH BE Liddell, KC Chaiko, DJ TI Metal ion separations using electrically switched ion exchange SO METAL SEPARATION TECHNOLOGIES BEYOND 2000: INTEGRATING NOVEL CHEMISTRY WITH PROCESSING LA English DT Proceedings Paper CT 3rd Engineering-Foundation Conference on Processes and Reagents for Metal Separations - Metal Separation Technologies Beyond 2000 CY JUN 13-18, 1999 CL KAHUKU, HI SP United Engn Fdn, Natl Sci Fdn, Minerals Met & Mat Soc, Amer Inst Chem Engineers ID INDUSTRIAL-SCALE REMOVAL; HEXACYANOFERRATE EXCHANGER; CESIUM AB Electrically Switched ion Exchange (ESIX) is an approach for ion separation that combines ion exchange (IX) and electrochemistry by utilizing electroactive IX films to provide a selective, reversible, and economical separation method that greatly reduces secondary waste generation compared with conventional ion exchange. Studies on the development of films with improved stability and capacity and their use in continuous flow systems for ion separations will be reported. Both technical and economic evaluations demonstrate the viability of once-through or batch recycle waste processing with ESIX. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Lilga, MA (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999, Richland, WA 99352 USA. NR 10 TC 1 Z9 1 U1 0 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-442-9 PY 1999 BP 269 EP 279 PG 11 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical; Metallurgy & Metallurgical Engineering SC Chemistry; Engineering; Metallurgy & Metallurgical Engineering GA BN16X UT WOS:000080927700024 ER PT B AU Hobbs, DT Steimke, JL Kurath, DE Balagopal, S Landro, T Sutija, DP Genders, JD Chai, D AF Hobbs, DT Steimke, JL Kurath, DE Balagopal, S Landro, T Sutija, DP Genders, JD Chai, D BE Liddell, KC Chaiko, DJ TI Recovery of sodium hydroxide from alkaline waste solutions SO METAL SEPARATION TECHNOLOGIES BEYOND 2000: INTEGRATING NOVEL CHEMISTRY WITH PROCESSING LA English DT Proceedings Paper CT 3rd Engineering-Foundation Conference on Processes and Reagents for Metal Separations - Metal Separation Technologies Beyond 2000 CY JUN 13-18, 1999 CL KAHUKU, HI SP United Engn Fdn, Natl Sci Fdn, Minerals Met & Mat Soc, Amer Inst Chem Engineers ID ELECTRODIALYSIS AB Large quantities of highly alkaline, radioactive, liquid wastes are stored in underground tanks throughout the Department of Energy complex. These wastes will be pretreated to separate radionuclides and the remaining decontaminated liquid wastes incorporated into solid wasteforms for permanent disposal. Significant savings in disposal costs could result by recovering the sodium as sodium hydroxide for reuse or disposal as nonradioactive waste. C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Hobbs, DT (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. NR 12 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 0-87339-442-9 PY 1999 BP 281 EP 292 PG 12 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical; Metallurgy & Metallurgical Engineering SC Chemistry; Engineering; Metallurgy & Metallurgical Engineering GA BN16X UT WOS:000080927700025 ER PT B AU Law, JD Herbst, RS Todd, TA Wood, DJ AF Law, JD Herbst, RS Todd, TA Wood, DJ BE Liddell, KC Chaiko, DJ TI Development of countercurrent solvent extraction processes for treatment of highly radioactive waste streams using centrifugal contactors SO METAL SEPARATION TECHNOLOGIES BEYOND 2000: INTEGRATING NOVEL CHEMISTRY WITH PROCESSING LA English DT Proceedings Paper CT 3rd Engineering-Foundation Conference on Processes and Reagents for Metal Separations - Metal Separation Technologies Beyond 2000 CY JUN 13-18, 1999 CL KAHUKU, HI SP United Engn Fdn, Natl Sci Fdn, Minerals Met & Mat Soc, Amer Inst Chem Engineers ID METAL-IONS; STRONTIUM; SREX; DERIVATIVES; ALKALI; SR-90 AB The presence of long-lived radionuclides presents a challenge to the management of radioactive wastes. Separation of the radionuclides from the waste solutions has the potential of significantly decreasing the costs associated with the immobilization and disposal of the waste by minimizing waste volumes. Several solvent extraction processes have been developed at the Idaho National Engineering and Environmental Laboratory for the separation of transuranic elements (TRUs), Sr-90, and/or Cs-137 from acidic radioactive waste solutions. The TRUEX and FOR processes for the separation of TRUs, the SREX process for the separation of Sr-90, the cobalt dicarbollide process for the separation of Cs-137 and Sr-90, and a universal solvent extraction process for the simultaneous separation of TRUs, Sr-90, and Cs-137 have all been developed in centrifugal contactors using actual liquid radioactive waste solutions and simulated dissolved calcine waste solution. In addition, the behavior of metals with each of the solvent extraction processes was evaluated. This article summarizes the most recent results of the each of the flowsheet demonstrations and provides information on the centrifugal contactor equipment used for the testing. C1 Idaho Natl Engn & Environm Lab, Lockheed Martin Idaho Technol, Idaho Falls, ID 83415 USA. RP Law, JD (reprint author), Idaho Natl Engn & Environm Lab, Lockheed Martin Idaho Technol, POB 1625, Idaho Falls, ID 83415 USA. OI Todd, Terry/0000-0003-1324-6950; Law, Jack/0000-0001-7085-7542 NR 28 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 0-87339-442-9 PY 1999 BP 303 EP 314 PG 12 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical; Metallurgy & Metallurgical Engineering SC Chemistry; Engineering; Metallurgy & Metallurgical Engineering GA BN16X UT WOS:000080927700027 ER PT B AU Bhattacharyya, MH Blum, CA Wilson, AK AF Bhattacharyya, MH Blum, CA Wilson, AK BE Klaassen, CD TI The role of metallothionein in cadmium-induced bone resorption SO METALLOTHIONEIN IV LA English DT Proceedings Paper CT 4TH International Metallothionein Meeting (MT-97) CY 1997 CL KANSAS CITY, MO SP Monsanto, NIEHS, NCI, Bayer, Coca Cola, Soc Toxicol, Searle, DowElanco, Nickel Producers Environm Res Assoc, Univ Kansas, Med Ctr, Westin Crown Ctr Hotel ID PROTECTIVE ROLE; IN-VITRO; MICE; CELLS; INDUCTION; DEFICIENT; EXPOSURE C1 Argonne Natl Lab, Ctr Mech Biol & Biotechnol, Argonne, IL 60439 USA. RP Bhattacharyya, MH (reprint author), Argonne Natl Lab, Ctr Mech Biol & Biotechnol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND BN 3-7643-5830-0 PY 1999 BP 473 EP 476 PG 4 WC Biochemistry & Molecular Biology; Toxicology SC Biochemistry & Molecular Biology; Toxicology GA BP39D UT WOS:000084979200069 ER PT J AU Mitlin, D Raeder, CH Messler, RW AF Mitlin, D Raeder, CH Messler, RW TI Solid solution creep behavior of Sn-xBi alloys SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID HARPER-DORN; STRESS AB This study details the steady-state creep properties of Sn-1 wt pet Bi, Sn-2 wt pet Bi, and Sn-5 wt pet Bi as a function of stress and temperature. All data, including previous work on pure Sn, are described by the following empirical equation: (epsilon)over dot(ss) = CE/RT sinh (alpha sigma/E) exp (-Q/RT) [1] Equation [1] describes steady-state creep where at low strain rates there is linear stress dependence and at high strain rates there is an exponential stress dependence. The transition in creep behavior occurs at a critical, breakaway stress, sigma(c) = E/alpha. This stress is compared to the breakaway stresses proposed by Friedel and by Cottrell and Jaswon. There is good agreement at low solute concentrations to the breakaway stress proposed by Friedel, but sigma(c) is significantly lower than the breakaway stress predicted by Cottrell and Jaswon. Several observations suggest that for Sn-xBi alloys, dislocation climb is the rate-limiting mechanism in the nonlinear region. First, the stress sensitivity of the steady-state strain rate data is similar to that of pure Sn, where dislocation climb is known to be the rate-limiting mechanism. Second, primary creep is observed throughout the tested stress range. Third, incremental additions of Bi decrease the steady-state creep rates, even though Bi has a higher diffusivity in Sn than Sn by self-diffusion. 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. Rensselaer Polytech Inst, Dept Mat Sci & Engn, Troy, NY 12180 USA. Adv Micro Devices, Austin, TX 78741 USA. RP Mitlin, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. RI Mitlin , David /M-5328-2016 OI Mitlin , David /0000-0002-7556-3575 NR 29 TC 28 Z9 31 U1 1 U2 7 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD JAN PY 1999 VL 30 IS 1 BP 115 EP 122 DI 10.1007/s11661-999-0199-1 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 154CT UT WOS:000077871500009 ER PT J AU Lexa, D AF Lexa, D TI Preparation and physical characteristics of a lithium-beryllium-substituted fluorapatite SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article AB A lithium-beryllium-substituted fluorapatite, Li0.50Be0.25Ca4.50(PO4)(3)F, has been prepared by means of a high-temperature reaction between lithium beryllium fluoride, Li2BeF4, and tricalcium phosphate, Ca-3(PO4)(2). This material has potential application as a waste form for radioactive and toxic fluoride salts. Monitoring of the reaction progress by differential scanning calorimetry indicated that the reaction was initiated by melting of the fluoride salt and that it was fast and complete. While reactive sintering of lithium beryllium fluoride with tricalcium phosphate led to a rather porous product, melting of the reactants with subsequent solidification readily produced a substituted fluorapatite with a near-theoretical bulk density. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Lexa, D (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 6 Z9 6 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD JAN PY 1999 VL 30 IS 1 BP 147 EP 153 DI 10.1007/s11661-999-0202-x PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 154CT UT WOS:000077871500012 ER PT J AU Dunn, ML Ledbetter, H Li, Z AF Dunn, ML Ledbetter, H Li, Z TI Thermal expansion of morphologically textured short-fiber composites SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID REINFORCED COMPOSITES; HETEROGENEOUS MEDIA; AVERAGE STRESS; COEFFICIENTS; MODULI; MATRIX; ANISOTROPY; INCLUSIONS; STIFFNESS; BEHAVIOR AB We studied, both experimentally and theoretically, the thermoelastic response of short-fiber composites with a preferred orientation of the short fibers, i.e., a morphological texture. Our theoretical efforts are general, being applicable to any composite system with constituents that exhibit linear thermoelastic response. We propose a relatively simple micromechanics model to predict the thermal expansion coefficient (CTE), and give simple, easily used, results for orientation distributions of practical significance. We also present a convenient approach to represent the effects of texture on thermal expansion of short fiber composites, namely, a texture map. Our experimental efforts focus on a series of extruded SiC/Al short-fiber composites that we have fully characterized. This includes measurement of the complete set of elastic constants, the volume fraction, and the fiber orientation distribution function (ODF) using neutron diffraction. We measured the axial and transverse components of the overall CTEs of these composites using a quartz-rod dilatometer. Predictions are in good agreement with measurements. C1 Univ Colorado, Dept Mech Engn, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Boulder, CO 80303 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. RP Dunn, ML (reprint author), Univ Colorado, Dept Mech Engn, Boulder, CO 80309 USA. OI DUNN, MARTIN/0000-0002-4531-9176 NR 51 TC 7 Z9 7 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD JAN PY 1999 VL 30 IS 1 BP 203 EP 212 DI 10.1007/s11661-999-0208-4 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 154CT UT WOS:000077871500018 ER PT J AU Wiens, RC Huss, GR Burnett, DS AF Wiens, RC Huss, GR Burnett, DS TI The solar oxygen-isotopic composition: Predictions and implications for solar nebula processes SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID CARBONACEOUS CHONDRITES; METEORITES; FRACTIONATION; MURCHISON; WATER; GASES; ION; INCLUSIONS; COMPONENT; ANOMALIES AB The outer layers of the Sun are thought to preserve the average isotopic and chemical composition of the solar system. The solar O-isotopic composition is essentially unmeasured, though models based on variations in meteoritic materials yield several predictions. These predictions are reviewed and possible variations on these predictions are explored. In particular, the two-component mixing model of Clayton and Mayeda (1984) (slightly revised here) predicts solar compositions to lie along an extension of the calcium-aluminum-rich inclusion (CAI) (16)O line between (delta(18)O, delta(17)O)= (16.4, 11.4)parts per thousand and (12.3, 7.5)parts per thousand. Consideration of data from ordinary chondrites suggests that the range of predicted solar composition should extend to slightly lower delta(18)O values. The predicted solar composition is critically sensitive to the solid/gas ratio in the meteorite-forming region, which is often considered to be significantly enriched over solar composition. A factor of two solid/gas enrichment raises the predicted solar (delta(18)O, delta(17)O) values along an extension of the CAI (16)O line to (33, 28)parts per thousand. The model is also sensitive to the nebular O gas phase. If conversion of most of the gaseous O from CO to H(2)O occurred at relatively low temperatures and was incomplete at the time of CM aqueous alteration, the predicted nebular gas composition (and hence the solar composition) would be isotopically heavier along a slope 1/2 line. The likelihood of having a single solid nebular O component is discussed. A distribution of initial solid compositions along the CAI (16)O line (rather than simply as an end-member) would not significantly change the predictions above in at least one scenario. Even considering these variations within the mixing model, the predicted range of solar compositions is distinct from that expected if the meteoritic variations are due to non-mass-dependent fractionation. Thus, a measurement of the solar O composition to a precision of several permil would clearly distinguish between these theories and should clarify a number of other important issues regarding solar system formation. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. RP Wiens, RC (reprint author), Los Alamos Natl Lab, NIS-1,MS D466, Los Alamos, NM 87545 USA. EM rwiens@lanl.gov NR 53 TC 37 Z9 37 U1 1 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JAN PY 1999 VL 34 IS 1 BP 99 EP 107 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 161QX UT WOS:000078301400011 ER PT J AU Coulter, RL Kallistratova, MA AF Coulter, RL Kallistratova, MA TI The role of acoustic sounding in a high-technology era SO METEOROLOGY AND ATMOSPHERIC PHYSICS LA English DT Article; Proceedings Paper CT International Symposium of Acoustic Remote of the Atmosphere and Oceans CY JUL 06-10, 1998 CL VIENNA, AUSTRIA ID ATMOSPHERIC BOUNDARY-LAYER; REFRACTIVE-INDEX; SODAR DATA; HEAT-FLUX; FLUCTUATIONS; TEMPERATURE; TURBULENCE AB This paper presents a brief synopsis of past, current and anticipated progress and problems in the use of acoustic remote sensing for basic and applied research of the lower atmosphere. The potential and reality of the sodar for determination of meteorological parameters and turbulence characteristics is discussed. Sodars' place alongside other ground-based remote sensors, including radar wind profilers, radioacoustic sounding systems (RASS) and lidars, is elucidated. Areas of atmospheric research where Doppler sodar has certain advantages are described such as cost, sensitivity, spatial and temporal resolution and surface layer measurements. The use of sodar in networks of integrated radar/RASS systems designed to supply uninterrupted monitoring of atmospheric parameters for improvements in forecasts of weather and air quality is demonstrated. The special potential role of sodar in education and training of specialists is suggested to aid in developing and using new methods of atmospheric measurements and meeting the requirements of modern environmental science. A number of problems are formulated whose solution would favor further advancement of acoustic remote sensing in integrated systems for remote monitoring of the atmospheric boundary layer. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60514 USA. Russian Acad Sci, Obukhov Inst Atmospher Phys, Moscow 109017, Russia. RP Coulter, RL (reprint author), Argonne Natl Lab, Div Environm Res, Bldg 203, Argonne, IL 60514 USA. NR 47 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 VIENNA, AUSTRIA SN 0177-7971 J9 METEOROL ATMOS PHYS JI Meteorol. Atmos. Phys. PY 1999 VL 71 IS 1-2 BP 3 EP 13 DI 10.1007/s007030050038 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 264ZK UT WOS:000084213600002 ER PT J AU Coulter, RL Klazura, G Lesht, BM Martin, TJ Shannon, JD Sisterson, DL Wesely, ML AF Coulter, RL Klazura, G Lesht, BM Martin, TJ Shannon, JD Sisterson, DL Wesely, ML TI The Argonne Boundary Layer Experiments facility: Using minisodars to complement a wind profiler network SO METEOROLOGY AND ATMOSPHERIC PHYSICS LA English DT Article; Proceedings Paper CT International Symposium of Acoustic Remote of the Atmosphere and Oceans CY JUL 06-10, 1998 CL VIENNA, AUSTRIA AB A description of the Argonne Boundary Layer Experiments (ABLE) facility, located in southern Kansas, USA, to study the planetary boundary layer on a continuous basis is given. The use and role of the minisodars in these studies is shown to be important and necessary in the study of surface boundary layers, extension of wind profiles to the surface, and estimates of convergence/divergence over 50-100 km scales over this site. A description of the site and location and description of the instrument systems is given; products available through internet access are briefly described. Use of the site by cooperative investigations is also described and invited. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60514 USA. RP Coulter, RL (reprint author), Argonne Natl Lab, Div Environm Res, Bldg 203, Argonne, IL 60514 USA. NR 11 TC 9 Z9 9 U1 0 U2 0 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 VIENNA, AUSTRIA SN 0177-7971 J9 METEOROL ATMOS PHYS JI Meteorol. Atmos. Phys. PY 1999 VL 71 IS 1-2 BP 53 EP 59 DI 10.1007/s007030050043 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 264ZK UT WOS:000084213600007 ER PT J AU Zhang, S Williams, CJ Wormington, M Stevens, A Peltz, SW AF Zhang, S Williams, CJ Wormington, M Stevens, A Peltz, SW TI Monitoring mRNA decapping activity SO METHODS-A COMPANION TO METHODS IN ENZYMOLOGY LA English DT Article DE mRNA decay; mRNA turnover; decapping activity; Xenopus oocyte ID MESSENGER-RNA TURNOVER; SACCHAROMYCES-CEREVISIAE; CAP STRUCTURE; DEADENYLATION; ENZYME; YEAST; DECAY; DEGRADATION; TRANSCRIPT; STABILITY AB mRNA decapping is a common step shared between two important mRNA decay pathways in yeast, Saccharomyces cerevisiae. To investigate how mRNAs are decapped, we have developed an assay that can be easily used to measure the decapping activity. This assay has been used to isolate yeast strains with altered decapping activities. The results demonstrated that decreased decapping activity in vitro corresponds well with the decapping-deficient phenotype in vivo. This assay has been applied to the purified yeast decapping enzyme Dcp1 protein as well as crude yeast extracts and Xenopus oocyte extracts. (C) 1999 Academic Press. C1 Univ Med & Dent New Jersey, Robert Wood Johnson Med Sch, Dept Mol Genet & Microbiol, Piscataway, NJ 08854 USA. Univ Med & Dent New Jersey, Rutgers State Univ, Robert Wood Johnson Med Sch, Grad Program Mol Biosci, Piscataway, NJ 08854 USA. Canc Inst New Jersey, Piscataway, NJ 08854 USA. Univ Virginia, Dept Biol, Charlottesville, VA 22903 USA. Oak Ridge Natl Lab, Div Biol, Oak Ridge, TN 37831 USA. RP Peltz, SW (reprint author), Univ Med & Dent New Jersey, Robert Wood Johnson Med Sch, Dept Mol Genet & Microbiol, Piscataway, NJ 08854 USA. EM Peltz@UMDNJ.EDU NR 32 TC 47 Z9 48 U1 0 U2 3 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1046-2023 J9 METHODS JI Methods PD JAN PY 1999 VL 17 IS 1 BP 46 EP 51 DI 10.1006/meth.1998.0706 PG 6 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 178GM UT WOS:000079257900007 PM 10075882 ER PT S AU Radnedge, L Richards, H AF Radnedge, L Richards, H BE Smith, MCM Sockett, RE TI The development of plasmid vectors SO METHODS MICROBIOLOGY, VOL 29: GENETIC METHODS FOR DIVERSE PROKARYOTES SE Methods in Microbiology LA English DT Review ID ROLLING-CIRCLE REPLICATION; COMPLETE NUCLEOTIDE-SEQUENCE; GRAM-NEGATIVE BACTERIA; HOST-RANGE PLASMIDS; COPY NUMBER CONTROL; F-TRANSFER REGION; ESCHERICHIA-COLI; DNA-REPLICATION; BACILLUS-SUBTILIS; INITIATION PROTEIN C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Environm Mol Microbiol Lab, Livermore, CA 94551 USA. UCL, Dept Biol, London WC1E 6BT, England. RP Radnedge, L (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Environm Mol Microbiol Lab, POB 808, Livermore, CA 94551 USA. NR 176 TC 1 Z9 1 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 0580-9517 BN 0-12-521529-0 J9 METHOD MICROBIOL JI Methods Microbiol. PY 1999 VL 29 BP 51 EP 96 PG 46 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA BN57D UT WOS:000082271400002 ER PT B AU Graham, RM AF Graham, RM GP NCSL/NIST NCSL/NIST NCSL/NIST TI Precise time transfer, or does anybody really know what time is it? SO METROLOGY - AT THE THRESHOLD OF THE CENTURY ARE WE READY? LA English DT Proceedings Paper CT 1999 Workshop and Symposium on Metrology - At the Threshold of the Century are we Ready CY JUL 11-15, 1999 CL CHARLOTTE, NC C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Graham, RM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NATL CONFERENCE STANDARDS LAB PI BOULDER PA 1800 30TH STREET, SUITE 305B, BOULDER, CO 80301 USA PY 1999 BP 43 EP 43 PG 1 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BP60M UT WOS:000085623700004 ER PT B AU Reda, I AF Reda, I GP NCSL/NIST NCSL/NIST NCSL/NIST TI Improving the accuracy of using pyranometers to measure the clear sky global solar irradiance SO METROLOGY - AT THE THRESHOLD OF THE CENTURY ARE WE READY? LA English DT Proceedings Paper CT 1999 Workshop and Symposium on Metrology - At the Threshold of the Century are we Ready CY JUL 11-15, 1999 CL CHARLOTTE, NC AB Pyranometer users have customarily applied one responsivity value when calculating the global solar irradiance. Usually, the responsivity value is reported by either the manufacturer or a calibration facility. Many pyranometer calibrations, made both at NREL and elsewhere, have shown that the responsivity of a pyranometer changes with the change in solar zenith and azimuth angles. Depending on how well the pyranometer sensor is radiometrically leveled, these changes can exceed +/-5% of the reported responsivity, which means that errors in the calculated global solar irradiance can exceed +/-5% from the nominal values. This paper describes a method to decrease the errors resulting from the change of the solar zenith angle under clear sky conditions. Two responsivity functions, morning and afternoon, were used instead of one responsivity value. The two functions have been chosen because of asymmetry of the morning and afternoon cosine responses demonstrated by some pyranometers. C1 Ctr Renewable Energy Resources, Natl Renewable Energy Lab, Golden, CO USA. RP Reda, I (reprint author), Ctr Renewable Energy Resources, Natl Renewable Energy Lab, Golden, CO USA. NR 2 TC 0 Z9 0 U1 0 U2 1 PU NATL CONFERENCE STANDARDS LAB PI BOULDER PA 1800 30TH STREET, SUITE 305B, BOULDER, CO 80301 USA PY 1999 BP 135 EP 152 PG 18 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BP60M UT WOS:000085623700020 ER PT B AU Moody, H AF Moody, H GP NCSL/NIST NCSL/NIST NCSL/NIST TI Air speed calibration standards at the Idaho national engineering and environmental laboratory (INEEL) SO METROLOGY - AT THE THRESHOLD OF THE CENTURY ARE WE READY? LA English DT Proceedings Paper CT 1999 Workshop and Symposium on Metrology - At the Threshold of the Century are we Ready CY JUL 11-15, 1999 CL CHARLOTTE, NC C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83401 USA. RP Moody, H (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83401 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NATL CONFERENCE STANDARDS LAB PI BOULDER PA 1800 30TH STREET, SUITE 305B, BOULDER, CO 80301 USA PY 1999 BP 435 EP 435 PG 1 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BP60M UT WOS:000085623700055 ER PT B AU Hardy, JE Hylton, JO McKnight, TE AF Hardy, JE Hylton, JO McKnight, TE GP NCSL/NIST NCSL/NIST NCSL/NIST TI Empirical correlations for thermal flowmeters covering a wide range of thermal-physical properties SO METROLOGY - AT THE THRESHOLD OF THE CENTURY ARE WE READY? LA English DT Proceedings Paper CT 1999 Workshop and Symposium on Metrology - At the Threshold of the Century are we Ready CY JUL 11-15, 1999 CL CHARLOTTE, NC AB Thermal flowmeters can provide direct mass flow measurement of gases and vapors over a wide range of process conditions without the need for density corrections based on pressure and temperature. They are widely used in industrial processes that contain toxic, corrosive, or highly reactive gases. It is often not possible to calibrate the flowmeter on the process gas in which it will be used. In this case a non-hazardous "surrogate" gas is used for-calibration, and a theoretical model used to predict the meter's response in the process gas. This can lead to large measurement errors because there are no accurate and straightforward methods for predicting the performance on one kind of gas based on the calibration on another gas because of the complexity of the thermal processes within the flow sensor. This paper describes some of the commonly used models and conversion methods and presents work done at ORNL to develop and experimentally verify better thermal models for predicting flowmeter performance. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hardy, JE (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI McKnight, Tim/H-3087-2011 OI McKnight, Tim/0000-0003-4326-9117 NR 4 TC 0 Z9 0 U1 0 U2 1 PU NATL CONFERENCE STANDARDS LAB PI BOULDER PA 1800 30TH STREET, SUITE 305B, BOULDER, CO 80301 USA PY 1999 BP 735 EP 747 PG 13 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BP60M UT WOS:000085623700095 ER PT S AU Karnowski, TP Tobin, KW Gleason, SS Lakhani, F AF Karnowski, TP Tobin, KW Gleason, SS Lakhani, F BE Singh, B TI The application of spatial signature analysis to electrical test data: Validation study SO METROLOGY, INSPECTION, AND PROCESS CONTROL FOR MICROLITHOGRAPHY XIII, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Metrology, Inspection, and Process Control for Microlithography XIII CY MAR 15-18, 1999 CL SANTA CLARA, CA SP SPIE, Semiconductor Equipment & Mat Int DE wafermap analysis; process signatures; automation; electrical test; yield learning; image processing AB This paper presents the results of the Spatial Signature Analysis (SSA) Electrical-test (e-test) validation study that was conducted between February and June, 1998. SSA is an automated procedure developed by researchers at the Oak Ridge National Laboratory to address the issue of intelligent data reduction while providing feedback on current manufacturing processes. SSA was initially developed to automate the analysis of optical defect data. Optical defects can form groups, or clusters, which may have a distinct shape. These patterns can reveal information about the manufacturing process. Optical defect SSA uses image processing algorithms and a classifier system to interpret and identify these patterns, or "signatures". SSA has been extended to analyze and interpret electrical test data. The algorithms used for optical defect SSA have; been adapted and applied to e-test binmaps. An image of the binmap is created, and features such as geometric and invariant moments are extracted and presented to a pair-wise, fuzzy, k-NN classifier. The classifier itself was prepared by manually training, which consists of storing example signatures of interest in a library, then executing an automated process which treats the examples as prototype signatures. The training process includes a procedure for automatically determining which features are most relevant to each class. The evaluation was performed by installing the SSA software as a batch process at three SEMATECH member company sites. Feedback from member company representatives was incorporated and classifiers were built to automatically assign labels to the binmap signatures. The three sites produced memory devices (DRAM) and microprocessors in a mature process fabrication environment. For all of these products, 5,620 signatures that encompassed approximately 552 wafers were human-classified and analyzed. The performance of the SSA E-test system indicates that the approach was successful in reliably classifying binmap signatures in a manner similar to the human expert. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Karnowski, TP (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 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 0-8194-3151-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3677 BP 530 EP 541 DI 10.1117/12.350840 PG 12 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Materials Science, Characterization & Testing; Optics; Physics, Applied SC Engineering; Instruments & Instrumentation; Materials Science; Optics; Physics GA BN32T UT WOS:000081633500050 ER PT S AU Sasaki, DY Waggoner, TA AF Sasaki, DY Waggoner, TA BE Ferrari, M TI Optical detection of aqueous phase analytes via host-guest interactions on a lipid membrane surface SO MICRO- AND NANOFABRICATED STRUCTURES AND DEVICES FOR BIOMEDICAL ENVIRONMENTAL APPLICATIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micro- and Nanofabricated Structures and Devices for Biomedical Environmental Applications II CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE molecular reorganization; membrane receptor; lipid bilayer; metal ion sensor; protein binding; fluorescence; pyrene ID ION AB The organization and assembly of molecules in cellular membranes is orchestrated through the recognition and binding of specific chemical signals. A simplified version of the cellular membrane system has been developed using a synthetically prepared membrane receptor incorporated into a biologically derived lipid bilayer. Through an interplay of electrostatic and van der Waals interactions, aggregation or dispersion of molecular components could be executed on command using a specific chemical signal. A pyrene fluorophore was used as an optical probe to monitor the aggregational state of the membrane receptors in the bilayer matrix. The pyrene excimer emission to monomer emission (E/M) intensity ratio gave a relative assessment of the local concentration of receptors in the membrane. Bilayers were prepared with receptors selective for the divalent metal ions of copper, mercury, and lead. Addition of the metal ions produced a rapid dispersion of aggregated receptor components at nano- to micro-molar concentrations. The process was reversible by sequestering the metal ions with EDTA. Receptors for proteins and polyhistidine were also prepared and incorporated into phosphatidylcholine lipid bilayers. In this case, the guest molecules bound to the membrane through multiple points of interaction causing aggregation of initially dispersed receptor molecules. The rapid, selective, and sensitive fluorescence optical response of these lipid assemblies make them attractive in sensor applications for aqueous phase metal ions and polypeptides. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sasaki, DY (reprint author), Sandia Natl Labs, MS 1407, Albuquerque, NM 87185 USA. NR 18 TC 4 Z9 4 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 0-8194-3076-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3606 BP 46 EP 54 DI 10.1117/12.350061 PG 9 WC Chemistry, Analytical; Engineering, Biomedical; Medical Laboratory Technology; Optics SC Chemistry; Engineering; Medical Laboratory Technology; Optics GA BN19W UT WOS:000081054000006 ER PT S AU Holman, HYN Zhang, MQ Goth-Goldstein, R Martin, MC Russell, M McKinney, WR Ferrari, M Hunter-Cevera, JC AF Holman, HYN Zhang, MQ Goth-Goldstein, R Martin, MC Russell, M McKinney, WR Ferrari, M Hunter-Cevera, JC BE Ferrari, M TI Detecting exposure to environmental organic toxins in individual cells: towards development of a micro-fabricated device SO MICRO- AND NANOFABRICATED STRUCTURES AND DEVICES FOR BIOMEDICAL ENVIRONMENTAL APPLICATIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micro- and Nanofabricated Structures and Devices for Biomedical Environmental Applications II CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE polycyclic aromatic hydrocarbons (PAHs); organochlorines (OCs); dioxin; infrared spectroscopy; CYP1A1; RT-PCR AB A new method is being developed for quickly screen for the human exposure potential to polycyclic aromatic hydrocarbons (PAHs) and organochlorines (OCs). The development involves two key elements: identifying suitable signals that represent intracellular changes that are specific to PAH and OC exposure, and constructing a device to guide the biological cell growth so that signals from individual cells are consistent and reproducible. We are completing the identification of suitable signals by using synchrotron radiation-based (SR) Fourier-transform infrared (FTIR) spectromicroscopy in the mid-infrared region (4000-400 cm(-1)). Distinct changes have been observed in the IR spectra after treatment of human cells in culture medium with PAHs and OCs. The potential use of this method for detecting exposure to PAHs and OCs has been tested and compared to a reverse transcription polymerase chain reaction (RT-PCR) assay that quantifies increased expression of the CYP1A1 gene in response to exposure to PAHs or OCs. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Environm Biotechnol, Berkeley, CA 94720 USA. RP Holman, HYN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Environm Biotechnol, Berkeley, CA 94720 USA. RI Holman, Hoi-Ying/N-8451-2014; OI Holman, Hoi-Ying/0000-0002-7534-2625; McKinney, Wayne/0000-0003-2586-3139; Zhang, Miqin/0000-0001-8974-1494 NR 7 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 0-8194-3076-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3606 BP 55 EP 62 DI 10.1117/12.350062 PG 8 WC Chemistry, Analytical; Engineering, Biomedical; Medical Laboratory Technology; Optics SC Chemistry; Engineering; Medical Laboratory Technology; Optics GA BN19W UT WOS:000081054000007 ER PT S AU Gourley, PL Akhil, O Copeland, GC Dunne, JL Hendricks, JK McDonald, AE Skirboll, SK Nihlen, L AF Gourley, PL Akhil, O Copeland, GC Dunne, JL Hendricks, JK McDonald, AE Skirboll, SK Nihlen, L BE Ferrari, M TI A semiconductor microlaser for intracavity flow cytometry SO MICRO- AND NANOFABRICATED STRUCTURES AND DEVICES FOR BIOMEDICAL ENVIRONMENTAL APPLICATIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micro- and Nanofabricated Structures and Devices for Biomedical Environmental Applications II CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE microfabrication; semiconductors; microlasers; flow cytometry; intracavity spectroscopy; vertical cavity surface-emitting lasers; blood analysis AB Semiconductor microlasers are attractive components for micro-analysis systems because of their ability to emit coherent, intense light from a small aperture. By using a surface-emitting semiconductor geometry, we were able to incorporate fluid now inside a laser microcavity for the first time. This confers significant advantages for high throughput screening of cells, particulates and fluid analytes in a sensitive microdevice. In this paper we discuss the intracavity microfluidics and present preliminary results with flowing blood and brain cells. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Gourley, PL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 19 TC 11 Z9 11 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 0-8194-3076-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3606 BP 64 EP 73 DI 10.1117/12.350063 PG 10 WC Chemistry, Analytical; Engineering, Biomedical; Medical Laboratory Technology; Optics SC Chemistry; Engineering; Medical Laboratory Technology; Optics GA BN19W UT WOS:000081054000008 ER PT S AU Mariella, R AF Mariella, R BE Ferrari, M TI Instrumentation for biomedical and environmental applications based on microtechnology - Lessons learned SO MICRO- AND NANOFABRICATED STRUCTURES AND DEVICES FOR BIOMEDICAL ENVIRONMENTAL APPLICATIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micro- and Nanofabricated Structures and Devices for Biomedical Environmental Applications II CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE microtechnology; instrumentation ID STREAM WAVE-GUIDE; COLLECTION AB Over the last ten years, LLNL has been developing Microtechnology for instrumentation with applications in the biosciences and environment. In order to build and field high-performance instruments, we have often had to alter our original premises and assumptions, significantly. This meant that we were forced to abandon materials and dimensions that were appealing to us when we began the R&D, Examples include our work on silicon-based electrophoresis systems, etched-fluidics for sample/sheath flow nozzles in flow cytometers, and polymerase-chain-reaction thermal-cycling; chambers based an silicon-nitride. This presentation will discuss these and our work on other devices and instruments. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Mariella, R (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,Mail Stop L-222, Livermore, CA 94551 USA. NR 11 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 0-8194-3076-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3606 BP 74 EP 81 PG 8 WC Chemistry, Analytical; Engineering, Biomedical; Medical Laboratory Technology; Optics SC Chemistry; Engineering; Medical Laboratory Technology; Optics GA BN19W UT WOS:000081054000009 ER PT S AU Swierkowski, SP Balch, JW Brewer, LR Copeland, AC Davidson, JC Fitch, JP Kimbrough, JR Madabhushi, RS Pastrone, RL Richardson, PM Tarte, LA Vainer, M AF Swierkowski, SP Balch, JW Brewer, LR Copeland, AC Davidson, JC Fitch, JP Kimbrough, JR Madabhushi, RS Pastrone, RL Richardson, PM Tarte, LA Vainer, M BE Ferrari, M TI Large microchannel array fabrication and results for DNA sequencing SO MICRO- AND NANOFABRICATED STRUCTURES AND DEVICES FOR BIOMEDICAL ENVIRONMENTAL APPLICATIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micro- and Nanofabricated Structures and Devices for Biomedical Environmental Applications II CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE microchannels; microchannel plates; DNA sequencing; electrophoresis; borosilicate glass ID CAPILLARY ELECTROPHORESIS; CHIP; SYSTEMS AB We have developed a process for the production of microchannel arrays on bonded glass substrates up to 14 x 58 cm, for DNA sequencing. Arrays of 96 and 384 microchannels, each 46 cm long have been built, This technology offers significant advantages over discrete capillaries or conventional slab-gel approaches. High throughput DNA sequencing with over 550 base pairs resolution has been achieved. With custom fabrication apparatus, microchannels are etched in a borosilicate substrate, and then fusion bonded to a top substrate 1.1 mm thick that has access holes formed in it. SEM examination shows a typical microchannel to be 40 x 180 micrometers by 96 cm long; the etch is approximately isotropic, leaving a key undercut, for forming a rounded channel. The surface roughness at the bottom of the 40 micrometer deep channel has been profilometer measured to be as low as 20 nm; the roughness at the top surface was 2 nm. Etch uniformity of about 5% has been obtained using a 22% vol. HF / 78% Acetic acid solution. The simple lithography, etching? and bonding of these substrates enables efficient production of these arrays and extremely precise replication from master masks and precision machining with a mandrel. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Swierkowski, SP (reprint author), Univ Calif Lawrence Livermore Natl Lab, MS L-222,7000 East Ave, Livermore, CA 94550 USA. RI Brewer, Laurence/G-4056-2012 NR 6 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 0-8194-3076-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3606 BP 100 EP 110 DI 10.1117/12.350050 PG 11 WC Chemistry, Analytical; Engineering, Biomedical; Medical Laboratory Technology; Optics SC Chemistry; Engineering; Medical Laboratory Technology; Optics GA BN19W UT WOS:000081054000012 ER PT S AU Benett, W Krulevitch, P AF Benett, W Krulevitch, P BE Ferrari, M TI A flexible packaging and interconnect scheme for microfluidic systems SO MICRO- AND NANOFABRICATED STRUCTURES AND DEVICES FOR BIOMEDICAL ENVIRONMENTAL APPLICATIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micro- and Nanofabricated Structures and Devices for Biomedical Environmental Applications II CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE microfluidics; interconnects; packaging; MEMS AB A slide-together compression package and microfluidic interconnects for microfabricated devices requiring fluidic and electrical connections is presented. The package assembles without tools, is reusable, and requires no epoxy, wirebonds, or solder, making chip replacement fast and easy. The microfluidic interconnects use standard HPLC PEEK tubing, with the tip machined to accept either an o-ring or custom molded ring which serves the dual function of forming the seal and providing mechanical retention strength. One design uses a screw to compress the o-ring, while others are simply plugged into a cartridge retained in the package. The connectors are helium leak-tight, can withstand hundreds of psi, are easy to connect and disconnect, are low dead volume, have a small footprint, and are adaptable to a broad range of microfabricated devices. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr MicroTechnol, Livermore, CA 94551 USA. RP Krulevitch, P (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr MicroTechnol, POB 808,L-222, Livermore, CA 94551 USA. NR 3 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 0-8194-3076-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3606 BP 111 EP 118 DI 10.1117/12.350051 PG 8 WC Chemistry, Analytical; Engineering, Biomedical; Medical Laboratory Technology; Optics SC Chemistry; Engineering; Medical Laboratory Technology; Optics GA BN19W UT WOS:000081054000013 ER PT S AU Miles, RR Schumann, DL AF Miles, RR Schumann, DL BE Ferrari, M TI Thin-walled compliant plastic structures for meso-scale fluidic systems SO MICRO- AND NANOFABRICATED STRUCTURES AND DEVICES FOR BIOMEDICAL ENVIRONMENTAL APPLICATIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micro- and Nanofabricated Structures and Devices for Biomedical Environmental Applications II CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE microfluidics; plastics; micropump; microvalve; micromixer; microfabrication AB Thin-walled, compliant plastic structures for meso-scale fluidic systems were fabricated, tested and used to demonstrate valving, pumping, metering and mixing. These structures permit the isolation of actuators and sensors from the working fluid, thereby reducing chemical compatibility issues. The thin-walled, compliant plastic structures can be used in either a permanent, reusable system or as an inexpensive disposable for single-use assay systems. The implementation of valving, pumping, mixing and metering operations involve only an elastic change in the mechanical shape of various portions of the structure. Advantages provided by the thin-walled plastic structures include reduced dead volume and rapid mixing. Five different methods for fabricating the thin-walled plastic structures discussed including laser welding, molding, vacuum forming, thermal heat staking and photolithographic patterning techniques. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Miles, RR (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 7 TC 0 Z9 0 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 0-8194-3076-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3606 BP 129 EP 136 DI 10.1117/12.350053 PG 8 WC Chemistry, Analytical; Engineering, Biomedical; Medical Laboratory Technology; Optics SC Chemistry; Engineering; Medical Laboratory Technology; Optics GA BN19W UT WOS:000081054000015 ER PT S AU Klimov, VI Schwarz, C Yang, X McBranch, DW Leatherdale, CA Bawendi, MG AF Klimov, VI Schwarz, C Yang, X McBranch, DW Leatherdale, CA Bawendi, MG BE Canham, LT Sailor, MJ Tanaka, K Tsai, CC TI Electron and hole relaxation pathways in II-VI semiconductor nanocrystals SO MICROCRYSTALLINE AND NANOCRYSTALLINE SEMICONDUCTORS-1998 SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microcrystalline and Nanocrystalline Semiconductors, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID CDSE QUANTUM DOTS; FEMTOSECOND NONLINEAR TRANSMISSION; ENERGY-RELAXATION; CARRIER DYNAMICS; LUMINESCENCE; ABSORPTION; TRANSITIONS; ASSIGNMENT; MECHANISM; CLUSTERS AB Femtosecond (fs) broad-band transient absorption (TA) is used to study the intra-band relaxation and depopulation dynamics of electron and hole quantized states in CdSe nanocrystals (NC's) with a range of surface properties. Instead of the drastic reduction in the energy relaxation rate expected due to a "phonon bottleneck", we observe a fast sub-picosecond 1P-to-1S relaxation, with the rate enhanced in NC's of smaller radius. We use fs IR TA to probe electron and hole intraband transitions, which allows us to distinguish between electron and hole pathways leading to the depopulation of NC quantized states. In contrast to electron relaxation, which is controlled by NC surface passivation, depopulation of hole quantized states is extremely fast (sub-ps-to-ps time scales) in all types samples, independent of NC surface treatment (including NC's overcoated with a ZnS layer). Our results indicate that ultrafast hole dynamics are not due to trapping at surface defects, but rather arise from relaxation into intrinsic NC states. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Klimov, VI (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, CST-6,MS-J585, Los Alamos, NM 87545 USA. NR 26 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 1-55899-442-4 J9 MATER RES SOC SYMP P PY 1999 VL 536 BP 211 EP 216 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA BN10V UT WOS:000080727100033 ER PT S AU Ginley, DS Curtis, CJ Ribelin, R Alleman, JL Mason, A Jones, KM Matson, RJ Khaselev, O Schulz, DL AF Ginley, DS Curtis, CJ Ribelin, R Alleman, JL Mason, A Jones, KM Matson, RJ Khaselev, O Schulz, DL BE Canham, LT Sailor, MJ Tanaka, K Tsai, CC TI Nanoparticle precursors for electronic materials SO MICROCRYSTALLINE AND NANOCRYSTALLINE SEMICONDUCTORS-1998 SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microcrystalline and Nanocrystalline Semiconductors, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID CDTE THIN-FILMS; SPRAY DEPOSITION; CELLS AB The use of nanoparticle precursors for electronic materials including sulfides, selenides, oxides and the elements has potentially wide ranging implications for improving device properties and substantially reducing the deposition costs. To realize this goal the complex interfacial chemistry of these small particles must be controlled. In this paper we present a number of cases demonstrating the complexity of this chemistry. These include CuInSe2 where the kinetics of phase formation dominate the sintering process; CdTe where sintering proceeds with and without the sintering enhancement of CdCl2, but produces materials different electronically than bulk materials; and the use of compound and elemental nanoparticles (Ag, Al, Hg-Cu-Te and Sb-Te) for contacts to elemental and compound semiconductors (Si and CdTe). C1 Natl Ctr Photovoltaics, Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Ginley, DS (reprint author), Natl Ctr Photovoltaics, Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-442-4 J9 MATER RES SOC SYMP P PY 1999 VL 536 BP 237 EP 244 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA BN10V UT WOS:000080727100037 ER PT S AU Zuhr, RA Budai, JD Datskos, PG Meldrum, A Thomas, KA Warmack, RJ White, CW Feldman, LC Strobel, M Heinig, KH AF Zuhr, RA Budai, JD Datskos, PG Meldrum, A Thomas, KA Warmack, RJ White, CW Feldman, LC Strobel, M Heinig, KH BE Canham, LT Sailor, MJ Tanaka, K Tsai, CC TI Nanostructured arrays formed by finely focused ion beams SO MICROCRYSTALLINE AND NANOCRYSTALLINE SEMICONDUCTORS-1998 SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microcrystalline and Nanocrystalline Semiconductors, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc AB Amorphous, polycrystalline, and single crystal nanometer dimension particles can be formed in a variety of substrates by ion implantation and subsequent annealing. Such composite colloidal materials exhibit unique optical properties that could be useful in optical devices, switches, and waveguides. However colloids formed by blanket implantation are not uniform in size due to the nonuniform density of the implant, resulting in diminution of the size dependent optical properties. The object of the present work is to form more uniform size particles arranged in a 2-dimensional lattice by using a finely focused ion beam to implant identical ion doses only into nanometer size regions located at each point of a rectangular lattice. Initial work is being done with a 30 keV Ga beam implanted into Si. Results of particle formation as a function of implant conditions as analyzed by Rutherford backscattering, x-ray analysis, atomic force microscopy, and both scanning and transmission electron microscopy will be presented and discussed. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Zuhr, RA (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 5 TC 1 Z9 1 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-442-4 J9 MATER RES SOC SYMP P PY 1999 VL 536 BP 251 EP 256 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA BN10V UT WOS:000080727100039 ER PT S AU Keblinski, P AF Keblinski, P BE Canham, LT Sailor, MJ Tanaka, K Tsai, CC TI Thermodynamics and kinetics of melting and growth of crystalline silicon clusters SO MICROCRYSTALLINE AND NANOCRYSTALLINE SEMICONDUCTORS-1998 SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microcrystalline and Nanocrystalline Semiconductors, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID MOLECULAR-DYNAMICS; AMORPHOUS-SILICON; TEMPERATURE AB Molecular-dynamics (MD) simulations and the Stillinger-Weber three-body potential are used to study the growth and stability of silicon clusters of diameters from 2 to 5 nm embedded in the melt. Our simulations show that the melting temperature of such nano-clusters is lower than the bulk melting temperature by an amount proportional to the inverse of the cluster size. We also show that the nature of the kinetics of such small Si clusters is essentially the same as that of the homoepitaxial growth. In particular, we show that the mobility of the highly-curved crystal liquid interface is controlled by diffusion in the adjacent melt, and is characterized by the same activation energy. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Keblinski, P (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-442-4 J9 MATER RES SOC SYMP P PY 1999 VL 536 BP 311 EP 316 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA BN10V UT WOS:000080727100049 ER PT S AU Meldrum, A Withrow, SP Zuhr, RA White, CW Boatner, LA Budai, JD Anderson, IM Henderson, DO Wu, M Ueda, A Mu, R AF Meldrum, A Withrow, SP Zuhr, RA White, CW Boatner, LA Budai, JD Anderson, IM Henderson, DO Wu, M Ueda, A Mu, R BE Canham, LT Sailor, MJ Tanaka, K Tsai, CC TI Microstructure and size distribution of compound semiconductor nanocrystals synthesized by ion implantation SO MICROCRYSTALLINE AND NANOCRYSTALLINE SEMICONDUCTORS-1998 SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microcrystalline and Nanocrystalline Semiconductors, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID BEAM SYNTHESIS AB Ion implantation is a versatile technique by which compound semiconductor nanocrystals may be synthesized in a wide variety of host materials. The component elements that form the compound of interest are implanted sequentially into the host, and nanocrystalline precipitates then form during thermal annealing. Using this technique, we have synthesized compound semiconductor nanocrystal precipitates of ZnS, CdS, PbS, and CdSe in a fused silica matrix. The resulting microstructures and size distributions were investigated by cross-sectional transmission electron microscopy. Several unusual microstructures were observed, including a band of relatively large nanocrystals at the end of the implant profile for ZnS and CdSe, polycrystalline agglomerates of a new phase such as gamma-Zn2SiO4, and the formation of central voids inside CdS nanocrystals. While each of these microstructures is of fundamental interest, such structures are generally not desirable for potential device applications for which a uniform, monodispersed array of nanocrystals is required. Methods were investigated by which these unusual microstructures could be eliminated. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Meldrum, A (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Boatner, Lynn/I-6428-2013; Budai, John/R-9276-2016 OI Boatner, Lynn/0000-0002-0235-7594; Budai, John/0000-0002-7444-1306 NR 8 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 1-55899-442-4 J9 MATER RES SOC SYMP P PY 1999 VL 536 BP 317 EP 322 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA BN10V UT WOS:000080727100050 ER PT S AU Geohegan, DB Puretzky, AA Meldrum, A Duscher, G Pennycook, SJ AF Geohegan, DB Puretzky, AA Meldrum, A Duscher, G Pennycook, SJ BE Canham, LT Sailor, MJ Tanaka, K Tsai, CC TI In situ diagnostics of nanomaterial synthesis by laser ablation: Time-resolved photoluminescence spectra and imaging of gas-suspended nanoparticles deposited for thin films SO MICROCRYSTALLINE AND NANOCRYSTALLINE SEMICONDUCTORS-1998 SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microcrystalline and Nanocrystalline Semiconductors, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID SILICON NANOCRYSTALLITES; WEBLIKE AGGLOMERATION; POROUS SILICON; INERT-GAS; LUMINESCENCE; SPECTROSCOPY; EMISSION; SIZE AB The dynamics of nanoparticle formation by laser ablation into background gases are revealed by gated-ICCD photography of photoluminescence (PL) and Rayleigh-scattering (RS) from gas-suspended nanoparticles. These techniques, along with gated-spectroscopy of PL from isolated, gas-suspended nanoparticles, permit fundamental investigations of nanomaterial growth, doping, and luminescence properties prior to deposition for thin films. Using the time-resolved diagnostics, particles unambiguously formed in the gas phase were collected on TEM grids. Silicon nanoparticles, 1-10 nm in diameter, were deposited following laser ablation into 1-10 Torr Ar or He. Three in situ PL bands (1.8, 2.6, 3.2 eV) similar to oxidized porous silicon were measured, but with a pronounced vibronic structure. Structureless photoluminescence bands were reproduced in the films (2.1, 2.7, 3.2 eV) only after standared annealing. The ablation of metal zinc into Ar/O-2 is also reported for the preparation of < 10 nm diameter hexagonal zincite nanocrystals, The particles were analyzed by bright field and Z-contrast TEM and high resolution EELS. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Geohegan, DB (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Duscher, Gerd/G-1730-2014; Puretzky, Alexander/B-5567-2016; Geohegan, David/D-3599-2013 OI Duscher, Gerd/0000-0002-2039-548X; Puretzky, Alexander/0000-0002-9996-4429; Geohegan, David/0000-0003-0273-3139 NR 23 TC 1 Z9 1 U1 0 U2 6 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-442-4 J9 MATER RES SOC SYMP P PY 1999 VL 536 BP 359 EP 364 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA BN10V UT WOS:000080727100057 ER PT S AU Schulz, DL Ribelin, R Curtis, CJ King, DE Ginley, DS AF Schulz, DL Ribelin, R Curtis, CJ King, DE Ginley, DS BE Canham, LT Sailor, MJ Tanaka, K Tsai, CC TI Nanoparticle-based contacts to CdTe SO MICROCRYSTALLINE AND NANOCRYSTALLINE SEMICONDUCTORS-1998 SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microcrystalline and Nanocrystalline Semiconductors, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc AB Our team has been investigating the use of particle-based contacts in CdTe solar cell technologies. Toward this end, particles of Cu-doped HgTe (Hg-Cu-Te) and Sb-Te have been applied as contacts to CdTe/CdS/SnO2 heterostructures. These metal telluride materials were characterized by standard methods. Hg-Cu-Te particles in graphite electrodag contacts produced CdTe solar cells with efficiencies above 12% and series resistance (R-se) of 6 Omega or less. Metathesis preparation of Cu(I) and Cu(II) tellurides (i.e., Cu2Te and CuTe, respectively) were attempted as a means of characterizing the valence state of Cu in the Hg-Cu-Te ink. For Sb-Te contacts to CdTe, open circuit voltages (V(oc)s) in excess of 800 mV were observed, however, efficiencies were limited to 9%; perhaps a consequence of the marked increase in the R-se (i.e., >20 Omega) in these non-graphite containing contacts. Acetylene black was mixed into the methanolic Sb-Te colloid as a means of reducing R-se, however, no improvement in device properties was observed. C1 Natl Renewable Energy Lab, Photovoltaic & Elect Mat Ctr, Golden, CO 80401 USA. RP Schulz, DL (reprint author), Natl Renewable Energy Lab, Photovoltaic & Elect Mat Ctr, Golden, CO 80401 USA. NR 2 TC 0 Z9 0 U1 1 U2 5 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-442-4 J9 MATER RES SOC SYMP P PY 1999 VL 536 BP 407 EP 411 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA BN10V UT WOS:000080727100065 ER PT S AU Fleming, JG Lin, SY AF Fleming, JG Lin, SY BE Ahn, CH Frazier, AB TI 3-D silicon photonic lattices - Cornerstone of an emerging photonics revolution SO MICROFLUIDIC DEVICES AND SYSTEMS II SE Proceedings of SPIE LA English DT Proceedings Paper CT SPIE Conference on Microfluidic Devices and Systems II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE 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-lice 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 24 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 0-8194-3474-4 J9 PROC SPIE PY 1999 VL 3877 BP 9 EP 18 DI 10.1117/12.361218 PG 10 WC Engineering, Mechanical; Optics; Physics, Applied SC Engineering; Optics; Physics GA BP26J UT WOS:000084509600002 ER PT S AU Lin, YH Wen, J Fan, X Matson, DW Smith, RD AF Lin, YH Wen, J Fan, X Matson, DW Smith, RD BE Ahn, CH Frazier, AB TI Laser micromachined isoelectric focusing device on polymer substrate for electrospray mass spectrometry SO MICROFLUIDIC DEVICES AND SYSTEMS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Microfluidic Devices and Systems II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE DE microchip; electrospray ionization; isoelectric focusing; proteins; mass spectrometry ID CAPILLARY-ELECTROPHORESIS; MICROFABRICATED DEVICE; MICROCHIP; SYSTEMS AB A microfabricated device for isoelectric focusing (IEF) incorporating an optimized electrospray ionization (ESI) tip was constructed on polycarbonate plates using a laser micromachining technique. The separation channels on an JEF chip were 16 cm long, 50 mu m wide and 30 mu m deep. Electrical potentials used for IEF focusing and electrospray were applied through platinum electrodes placed in the buffer reservoirs, and which were isolated from the separation channel by molecular porous membranes. On-line ESI produced directly from a sharp "tip" on the microchip was evaluated. The results indicate that this design can produce a stable electrospray that is further improved and made more flexible with the assistance of a sheath gas and sheath liquid. Error analysis of the spectral data shows that the standard deviation in signal intensity for an analyte peak was less than similar to 5% over 3 hours. The production of stable electrosprays directly from microchip IEF devices represents a step towards easily-fabricated microanalytical devices. IEF separations of protein mixtures were demonstrated for uncoated polycarbonate microchips. On-line IEF/ESI-MS was demonstrated using the microfabricated chip with an ion-trap ESI mass spectrometer for characterization of protein mixtures. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Lin, YH (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999, Richland, WA 99352 USA. RI Lin, Yuehe/D-9762-2011; Smith, Richard/J-3664-2012 OI Lin, Yuehe/0000-0003-3791-7587; Smith, Richard/0000-0002-2381-2349 NR 23 TC 9 Z9 9 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 0-8194-3474-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3877 BP 28 EP 35 DI 10.1117/12.359351 PG 8 WC Engineering, Mechanical; Optics; Physics, Applied SC Engineering; Optics; Physics GA BP26J UT WOS:000084509600004 ER PT S AU Matson, DW Martin, PM Bennett, WD Stewart, DC Bonham, CC AF Matson, DW Martin, PM Bennett, WD Stewart, DC Bonham, CC BE Ahn, CH Frazier, AB TI Laminated ceramic components for micro fluidic applications SO MICROFLUIDIC DEVICES AND SYSTEMS II SE Proceedings of SPIE LA English DT Proceedings Paper CT SPIE Conference on Microfluidic Devices and Systems II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE DE ceramic; laminate; microchannel; chemical; micro fluidic AB Applications for micro fluidic components continue to expand as the benefits resulting from the small volumes and light weight of such devices are recognized. Such benefits are particularly attractive for man-portable and automotive devices where reduction of weight is critical. As applications expand, so too does the need for the development of methods for producing micro fluidic components from unconventional materials (i.e., materials other than silicon). At the Pacific Northwest National Laboratory (PNNL), we are currently developing processes for producing laminated multilevel ceramic components containing microchannel features that will find applications in micro fluidic chemical processing and energy management systems. Thin layers of green ceramic tape are patterned with micro fluidic flow features using one of a number of cutting processes. The patterned layers are then stacked and laminated with other layers of green tape, ceramic plate, or other materials using a series of processing steps. The resulting monolithic, leak-tight micro fluidic ceramic components are capable of tolerating high temperature or chemically corrosive environments. Fabrication issues associated with the use of the green ceramic tape for this type of application will be discussed, and examples of test components produced using these processes will be presented. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Matson, DW (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999,MSIN K3-59, Richland, WA 99352 USA. NR 4 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 0-8194-3474-4 J9 PROC SPIE PY 1999 VL 3877 BP 95 EP 100 DI 10.1117/12.359326 PG 6 WC Engineering, Mechanical; Optics; Physics, Applied SC Engineering; Optics; Physics GA BP26J UT WOS:000084509600012 ER PT S AU Matzke, CM Ashby, CIH Bridges, M Griego, L Wong, C AF Matzke, CM Ashby, CIH Bridges, M Griego, L Wong, C BE Ahn, CH Frazier, AB TI Integratible process for fabrication of fluidic microduct networks on a single wafer SO MICROFLUIDIC DEVICES AND SYSTEMS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Microfluidic Devices and Systems II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE DE microduct; microchannel; microfluidic; integratible microchannel; sealed microchannel; microfabricated channel; MEMS microchannel; elastic modulus ID SILICON AB We present a microelectronics fabrication compatible process that comprises photolithography and a key room temperature SiON thin film plasma deposition to define and seal a fluidic microduct network. Our single wafer process is independent of thermo-mechanical material properties, particulate cleaning, global flatness, assembly alignment, and glue medium application, which are crucial for wafer fusion bonding or sealing techniques using a glue medium. From our preliminary experiments, we have identified a processing window to fabricate channels on silicon, glass and quartz substrates. Channels with a radius of curvature between 8 and 50 mm, are uniform along channel lengths of several inches and repeatable across the wafer surfaces. To further develop this technology, we have begun characterizing the SiON film properties such as elastic modulus using nanoindentation, and chemical bonding compatibility with other microelectronic materials. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Matzke, CM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. 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 0-8194-3474-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3877 BP 110 EP 118 DI 10.1117/12.359328 PG 9 WC Engineering, Mechanical; Optics; Physics, Applied SC Engineering; Optics; Physics GA BP26J UT WOS:000084509600014 ER PT S AU Wong, CC Adkins, DR Frye-Mason, GC Hudson, ML Kottenstette, R Matzke, CM Shadid, JN Salinger, AG AF Wong, CC Adkins, DR Frye-Mason, GC Hudson, ML Kottenstette, R Matzke, CM Shadid, JN Salinger, AG BE Ahn, CH Frazier, AB TI Modeling transport in gas chromatography columns for the Micro-ChemLab (TM) SO MICROFLUIDIC DEVICES AND SYSTEMS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Microfluidic Devices and Systems II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE DE Micro-ChemLab; gas chromatography; adsorption/desorption; separation; microscale transport AB The gas chromatography (GC) column is a critical component in the microsystem for chemical detection (mu ChemLab(TM)) being developed at Sandia. The goal is to etch a 'meter-long' GC column onto a I-cm? silicon chip while maintaining good chromatographic performance. Our design strategy is to use modeling and simulation approach. We have developed an analytical tool that models the transport and surface interaction process to achieve an optimized design of the GC column. This analytical tool has a flow module and a separation module. The flow module considers both the compressibility and slip flow effects that may significantly influence the gas transport in a long and narrow column. The separation module models analyte transport and physico-chemical interaction with the coated surface in the GC column. It predicts the column efficiency and performance. Results of our analysis will be presented in this paper. In addition to the analytical tool, we have also developed a time-dependent adsorption/desorption model and incorporated this model into a computational fluid dynamics (CFD) code to simulate analyte transport and separation process in GC columns. CFD simulations can capture the complex three-dimensional flow and transport dynamics, where as the analytical tool cannot provide. Different column geometries have been studied and results will be presented in this paper. Overall, we have demonstrated that the modeling and simulation approach can guide the design of the GC column and will reduce the number of iterations in the device development. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wong, CC (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 13 TC 1 Z9 1 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 0-8194-3474-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3877 BP 120 EP 129 DI 10.1117/12.359329 PG 10 WC Engineering, Mechanical; Optics; Physics, Applied SC Engineering; Optics; Physics GA BP26J UT WOS:000084509600015 ER PT S AU Arnold, DW Paul, PH AF Arnold, DW Paul, PH BE Ahn, CH Frazier, AB TI Fluorescence-based visualization of electroosmotic flow in microfabricated systems SO MICROFLUIDIC DEVICES AND SYSTEMS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Microfluidic Devices and Systems II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE DE flow imaging; microfluid channels; micro total analysis system; fluorescence; capillary electrophoresis; electroosmotic flow ID CAPILLARIES AB A recently developed imaging tool is employed to study scaler transport in microfabricated fluidic manifolds. Using the two-color fluorescence-based method to generate molecular fluid flow tracers, we investigate electrokinetic flow through channel geometries commonly encountered in micro-total analytical system research and development. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Arnold, DW (reprint author), Sandia Natl Labs, POB 969,MS 9671, Livermore, CA 94550 USA. NR 5 TC 4 Z9 4 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 0-8194-3474-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3877 BP 174 EP 179 DI 10.1117/12.359335 PG 6 WC Engineering, Mechanical; Optics; Physics, Applied SC Engineering; Optics; Physics GA BP26J UT WOS:000084509600021 ER PT S AU Cummings, EB Griffiths, SK Nilson, RH AF Cummings, EB Griffiths, SK Nilson, RH BE Ahn, CH Frazier, AB TI Irrotationality of uniform electroosmosis SO MICROFLUIDIC DEVICES AND SYSTEMS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Microfluidic Devices and Systems II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE DE electroosmosis; electrophoresis; electrokinetic flow; microfluidics; fluid mechanics; potential flow; particle-image velocimetry; fluorescence; electric double layer; Debye layer ID PARTICLE AB Steady electroosmotic flow of uniform liquids in uniform media is irrotational provided the electric double layers adjacent to surfaces are negligibly thin, the surfaces are non-conducting and impermeable, and the total pressure imposed at inlets and outlets is uniform. Because many microfluidic devices employing electroosmosis approximately satisfy these requirements, this ideal electroosmosis is a limiting case with considerable practical significance. In ideal electroosmosis, fluid motion follows current lines. Flow-fields have no Reynolds number dependence and are everywhere proportional to the electric field. Both fields may be obtained by a single solution of the Laplace equation. In this paper, we discuss these features of ideal electroosmotic flows and present particle-image derived velocity fields that confirm ideal flow conditions in glass microchannel networks. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Cummings, EB (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94550 USA. NR 11 TC 12 Z9 12 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 0-8194-3474-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3877 BP 180 EP 189 DI 10.1117/12.359336 PG 10 WC Engineering, Mechanical; Optics; Physics, Applied SC Engineering; Optics; Physics GA BP26J UT WOS:000084509600022 ER PT S AU Fintschenko, Y Arnold, D Peters, E Svec, F Frechet, J AF Fintschenko, Y Arnold, D Peters, E Svec, F Frechet, J BE Ahn, CH Frazier, AB TI Characterization of porous polymer monoliths as flow restrictors for capillary electrophoresis on a chip SO MICROFLUIDIC DEVICES AND SYSTEMS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Microfluidic Devices and Systems II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE DE capillary electrophoresis; porous polymer monolith; flow restriction; zeta potential; electroosmotic flow ID SEPARATIONS AB Capillary electrophoresis (CE) lends itself to miniaturization, because it uses electroosmotic flow rather than moving parts for flow generation. Its analytical figures of merit improve as channel dimensions decrease. However, solution flow in the small planar channels used in CE-on-a-chip is very sensitive to reservoir solution height. This adds a pressure driven flow component, which decreases resolution, sensitivity, and separation efficiency of the EOF-driven technique. We have observed that this contribution to parabolic flow from uneven solution heights can be minimized by using a porous polymer monolith (PPM) as a flow restriction plug in the reservoirs of a 75 mu m wide x 15 mu m deep microchannel etched in glass. Our results indicate an average PPM pore size of 1 mu m is sufficient for flow restriction. Pore sizes below this result in charge trapping of even small dye molecules. Images of the flow profile on and off the monolith show the inverse-parabolic effect on the electroosmotic flow profile due to mismatched zeta potentials between the polymer and the fused silica wall surfaces depending on PPM surface charge and plug length. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Fintschenko, Y (reprint author), Sandia Natl Labs, POB 969-MS 9671, Livermore, CA 94550 USA. OI Frechet, Jean /0000-0001-6419-0163 NR 8 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 0-8194-3474-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3877 BP 202 EP 209 DI 10.1117/12.359338 PG 8 WC Engineering, Mechanical; Optics; Physics, Applied SC Engineering; Optics; Physics GA BP26J UT WOS:000084509600024 ER PT S AU Lin, YH Zhao, R Thrall, KD Timchalk, CA Bennett, WD Matson, DW AF Lin, YH Zhao, R Thrall, KD Timchalk, CA Bennett, WD Matson, DW BE Ahn, CH Frazier, AB TI Integration of microfluidics/electrochemical system for trace metal analysis by stripping voltammetry SO MICROFLUIDIC DEVICES AND SYSTEMS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Microfluidic Devices and Systems II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE DE microfluidics; electrochemical detector; stripping voltammetry; lead ID MASS-SPECTROMETRY; MICROCHIP; SILICON AB Microanalytical systems based on a microfluidics/electrochemical detection scheme were developed. Individual modules, such as microfabricated piezoelectrically actuated pumps and a microelectrochemical cell were integrated onto portable platforms. This allowed rapid change-out and repair of individual components by incorporating "plug and play" concepts now standard in PC's. Two different integration schemes were used for construction of the microanalytical systems based on microfluidics/electrochemical detection. In first scheme, all individual modules were integrated in the surface of the standard microfluidic platform based on a plug-and-pray design. Microelectrochemical flow cell which integrated three electrodes based on a wall-jet design was fabricated on polymer substrate. The microelectrochemical flow cell was then plugged directly into the microfluidic platform. Another integration scheme was based on a multilayer lamination method utilizing stacking modules with different functionality to achieve a compact microanalytical device. Application of the microanalytical system for detection of lead in river water and saliva samples using stripping voltammetry is described. C1 Pacific NW Labs, Richland, WA 99352 USA. RP Lin, YH (reprint author), Pacific NW Labs, POB 999, Richland, WA 99352 USA. RI Lin, Yuehe/D-9762-2011 OI Lin, Yuehe/0000-0003-3791-7587 NR 12 TC 11 Z9 11 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 0-8194-3474-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3877 BP 248 EP 256 DI 10.1117/12.359343 PG 9 WC Engineering, Mechanical; Optics; Physics, Applied SC Engineering; Optics; Physics GA BP26J UT WOS:000084509600029 ER PT S AU Galambos, P Zavadil, K Shul, R Willison, CG Miller, S AF Galambos, P Zavadil, K Shul, R Willison, CG Miller, S BE Ahn, CH Frazier, AB TI Silicon nitride membranes for filtration and separation SO MICROFLUIDIC DEVICES AND SYSTEMS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Microfluidic Devices and Systems II CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE DE microfluidics; semi-permeable silicon nitride membrane AB Semi-Permeable silicon nitride membranes have been developed using a Bosch(1) etch process followed by a reactive ion etch (RIE) process. These membranes were observed to allow air but not water to pass through them into surface micromachined, silicon nitride microfluidic channels. Membranes with this property have potential use in microfluidic systems as gas bubble traps and vents, filters to remove particles and gas partitioning membranes. Membrane permeation was measured as 1.6 x 10(-8) mol / m(2)Pa s of helium for inline membranes at the entrance and exit of the silicon nitride microfluidic channels. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Galambos, P (reprint author), Sandia Natl Labs, POB 5800,MS 1080, Albuquerque, NM 87185 USA. NR 15 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 0-8194-3474-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3877 BP 273 EP 283 DI 10.1117/12.359346 PG 11 WC Engineering, Mechanical; Optics; Physics, Applied SC Engineering; Optics; Physics GA BP26J UT WOS:000084509600032 ER PT S AU Fleming, JG Lin, SY AF Fleming, JG Lin, SY BE Lee, SH Cox, JA TI 3-D silicon photonic lattices: cornerstone of an emerging photonics revolution SO MICROMACHINE TECHNOLOGY FOR DIFFRACTIVE AND HOLOGRAPHIC OPTICS SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Micromachine Technology for Diffractive and Holographic Optics CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semiconductor Equipment & Mat Int, Natl Inst Stand & Technol, Sandia Natl Labs, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliability Engn Assoc Japan DE photonic lattice; MEMS; infrared; photonic bandgap ID BAND-GAP; OPTICAL WAVELENGTHS; CRYSTAL 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 Sandia Natl Labs, Org 1723,MS 1084,POB 5800, Albuquerque, NM 87185 USA. NR 24 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 0-8194-3476-0 J9 PROC SPIE PY 1999 VL 3879 BP 9 EP 18 DI 10.1117/12.361218 PG 4 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN99L UT WOS:000083801900002 ER PT S AU Fleming, JG Lin, SY AF Fleming, JG Lin, SY BE French, PJ Peeters, E TI 3-D silicon photonic lattices- cornerstone of an emerging photonics revolution SO MICROMACHINED DEVICES AND COMPONENTS V SE Proceedings of SPIE LA English DT Proceedings Paper CT 5th Conference on Micromachined Devices and Components CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Stand & Technol, Sandia Natl Lab, 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, 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 0-8194-3473-6 J9 PROC SPIE PY 1999 VL 3876 BP 9 EP 18 PG 10 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BP12T UT WOS:000084200200002 ER PT S AU Dyck, CW Allen, JJ Huber, RJ AF Dyck, CW Allen, JJ Huber, RJ BE French, PJ Peeters, E TI Parallel-plate electrostatic dual-mass oscillator SO MICROMACHINED DEVICES AND COMPONENTS V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 5th Conference on Micromachined Devices and Components CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Stand & Technol, Sandia Natl Lab, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliabil Engn Assoc Japan DE surface micromachining; resonator; actuator; vibration absorber; motion amplifier AB A surface-micromachined two-degree-of-freedom system that was driven by parallel-plate actuation at antiresonance was demonstrated. The system consisted of an absorbing mass connected by folded springs to a drive mass. The system demonstrated substantial motion amplification at antiresonance. The absorber mass amplitudes were 0.8 - 0.85 mu m at atmospheric pressure while the drive mass amplitudes were below 0.1 mu m. Larger absorber mass amplitudes were not possible because of spring softening in the drive mass springs. Simple theory of the dual-mass oscillator has indicated that the absorber mass may be insensitive to limited variations in strain and damping. This needs experimental verification. Resonant and antiresonant frequencies were measured and compared to the designed values. Resonant frequency measurements were difficult to compare to the design calculations because of time-varying spring softening terms that were caused by the drive configuration. Antiresonant frequency measurements were close to the design value of 5.1 kHz. The antiresonant frequency was not dependent on spring softening. The measured absorber mass displacement at antiresonance was compared to computer simulated results. The measured value was significantly greater, possibly due to neglecting fringe fields in the force expression used in the simulation. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Dyck, CW (reprint author), Sandia Natl Labs, POB 5800,MS 1080, Albuquerque, NM 87185 USA. NR 5 TC 9 Z9 9 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 0-8194-3473-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3876 BP 198 EP 209 DI 10.1117/12.360495 PG 12 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BP12T UT WOS:000084200200021 ER PT S AU Rodgers, MS Allen, JJ Meeks, KD Jensen, BD Miller, SL AF Rodgers, MS Allen, JJ Meeks, KD Jensen, BD Miller, SL BE French, PJ Peeters, E TI A microelectromechanical high-density energy storage/rapid release system SO MICROMACHINED DEVICES AND COMPONENTS V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 5th Conference on Micromachined Devices and Components CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Stand & Technol, Sandia Natl Lab, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliabil Engn Assoc Japan DE microengine; microtranmission; microelectromechanical energy storage ID COMPLIANT MECHANISMS; DEFLECTION AB One highly desirable characteristic of electrostatically driven microelectromechanical systems (MEMS) is that they consume very little power. The corresponding drawback is that the force they produce may be inadequate for many applications. It has previously been demonstrated that gear reduction units or microtransmissions can substantially increase the torque generated by microengines [1,2]. Operating speed, however, is also reduced by the transmission gear ratio. Some applications require both high speed and high force. If this output is only required for a limited period of time, then energy could be stored in a mechanical system and rapidly released upon demand. We have designed, fabricated, and demonstrated a high-density energy storage / rapid release system that accomplishes this task. Built using a 5-level surface micromachining technology [3], the assembly closely resembles a medieval crossbow. Energy releases on the order of tens of nanojoules have already been demonstrated, and significantly higher energy systems are under development. C1 Sandia Natl Labs, Intelligent Micromachine Dept, Albuquerque, NM 87185 USA. RP Rodgers, MS (reprint author), Sandia Natl Labs, Intelligent Micromachine Dept, POB 5800,Mail Stop 1080, Albuquerque, NM 87185 USA. NR 15 TC 4 Z9 4 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 0-8194-3473-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3876 BP 212 EP 222 DI 10.1117/12.360496 PG 11 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BP12T UT WOS:000084200200022 ER PT S AU Morse, JD Jankowski, AF Hayes, JP Graff, RT AF Morse, JD Jankowski, AF Hayes, JP Graff, RT BE French, PJ Peeters, E TI A novel thin film solid oxide fuel cell for microscale energy conversion SO MICROMACHINED DEVICES AND COMPONENTS V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 5th Conference on Micromachined Devices and Components CY SEP 20-21, 1999 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Semicond Equipment & Mat Int, Natl Inst Stand & Technol, Sandia Natl Lab, Inst Elect Engineers Japan, Japan Soc Mech Engn, Reliabil Engn Assoc Japan DE fuel cell; solid-oxide; anode; cathode; porous; micromachined; manifold; thin-film; miniature ID YTTRIA-STABILIZED ZIRCONIA; SPUTTER-DEPOSITION; LOW-TEMPERATURE; ELECTROLYTES AB A novel approach for the fabrication and assembly of a solid oxide fuel cell system is described which enables effective scaling of the fuel delivery, manifold, and fuel cell stack components for applications in miniature and microscale energy conversion. Scaling towards miniaturization is accomplished by utilizing thin film deposition combined with novel micromachining approaches which allow manifold channels and fuel delivery system to be formed within the substrate which the thin film fuel cell stack is fabricated on, thereby circumventing the need for bulky manifold components which are not directly scalable. Results demonstrating the generation of electrical current in the temperature range of 200-400 degrees C for a thin film solid oxide fuel cell stack fabricated on a silicon wafer will be presented. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Morse, JD (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 10 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 0-8194-3473-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3876 BP 223 EP 226 DI 10.1117/12.360497 PG 4 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BP12T UT WOS:000084200200023 ER PT S AU Fleming, JG Lin, SY AF Fleming, JG Lin, SY BE Smith, JH Karam, JM TI 3-D silicon photonic lattices - cornerstone of an emerging photonics revolution SO MICROMACHINING AND MICROFABRICATION PROCESS TECHNOLOGY V SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Micromachining and Microfabrication Process Technology V CY SEP 20-22, 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 Sandia Natl Labs, POB 5800,Org 1723,MS 1084, Albuquerque, NM 87185 USA. NR 25 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 0-8194-3471-X J9 PROC SPIE PY 1999 VL 3874 BP 9 EP 18 DI 10.1117/12.361218 PG 10 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BP12R UT WOS:000084199900002 ER PT S AU Hruby, JM Griffiths, SK Domeier, LA Morales, AM Boehme, DR Bankert, MA Bonivert, WD Hachman, JT Skala, DM Ting, A AF Hruby, JM Griffiths, SK Domeier, LA Morales, AM Boehme, DR Bankert, MA Bonivert, WD Hachman, JT Skala, DM Ting, A BE Smith, JH Karam, JM TI LIGA: metals, plastics, and ceramics SO MICROMACHINING AND MICROFABRICATION PROCESS TECHNOLOGY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micromachining and Microfabrication Process Technology V CY SEP 20-22, 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; processing; replication; plastic; polymer; ceramic AB LIGA, an acronym from the German words for Lithography, Electroforming, and Molding, is being evaluated worldwide as a method to produce microparts from engineering materials. Much of the work to date in LIGA has focused on producing metal microparts, with nickel as the most common material of choice. There is a growing interest in producing plastic parts replicated from LIGA metal masters due largely to microanalytical instrumentation and medical applications. These plastic replicates are generally made by either hot embossing or injection molding. Ceramic replication, of particular interest for high temperature applications or to produce piezoelectric or magnetic microparts, is also emerging as an area of interest. In this paper, a model of the LIGA exposure and development processes is presented along with the results of numerical optimization of mask design and process cost. The baseline processes for a cost-effective method to produce metal microparts are discussed, along with replication methods and results for plastics and ceramics. C1 Sandia Natl Labs, Microtechnol Dept MS9401, Livermore, CA 94551 USA. RP Hruby, JM (reprint author), Sandia Natl Labs, Microtechnol Dept MS9401, Livermore, CA 94551 USA. NR 15 TC 8 Z9 8 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 0-8194-3471-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3874 BP 32 EP 43 DI 10.1117/12.361216 PG 12 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BP12R UT WOS:000084199900004 ER PT S AU Limary, S Stewart, H Irwin, L McBrayer, J Sniegowski, J Montague, S Smith, J de Boer, M Jakubczak, J AF Limary, S Stewart, H Irwin, L McBrayer, J Sniegowski, J Montague, S Smith, J de Boer, M Jakubczak, J BE Smith, JH Karam, JM TI Reproducibility data on SUMMiT SO MICROMACHINING AND MICROFABRICATION PROCESS TECHNOLOGY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micromachining and Microfabrication Process Technology V CY SEP 20-22, 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 Microelectromechanical Systems; MEMS; foundry; surface micromachining; polysilicon mechanical structures AB SUMMiT (Sandia Ultra-planar Multi-level MEMS Technology) at the Sandia National Laboratories' MDL (Microelectronics Development Laboratory) is a standardized MEMS (Microelectromechanical Systems) technology that allows designers to fabricate concept prototypes. This technology provides four polysilicon layers plus three sacrifcial oxide layers (with the third oxide layer being planarized) to enable fabrication of complex mechanical systems-on-a-chip. Quantified reproducibility of the SUMMiT process is important for process engineers as well as designers. Summary statistics for critical MEMS technology parameters such as film thickness, line width, and sheet resistance will be reported for the SUMMiT process. Additionally, data from Van der Pauw test structures will be presented. Data on film thickness, film uniformity and critical dimensions of etched line widths are collected from both process and monitor wafers during manufacturing using film thickness metrology tools and SEM tools. A standardized diagnostic module is included in each SUMMiT run to obtain post-processing parametric data to monitor run-to-run reproducibility such as Van der Pauw structures for measuring sheet resistance. This characterization of the SUMMiT process enables design for manufacturability in the SUEVIMIT technology. C1 Sandia Natl Labs, Intelligent Micromachine Dept, Albuquerque, NM 87185 USA. RP Limary, S (reprint author), Sandia Natl Labs, Intelligent Micromachine Dept, POB 5800,MS 1080, Albuquerque, NM 87185 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 0-8194-3471-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3874 BP 102 EP 112 DI 10.1117/12.361210 PG 11 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BP12R UT WOS:000084199900012 ER PT S AU Mani, SS Fleming, JG Sniegowski, JJ AF Mani, SS Fleming, JG Sniegowski, JJ BE Smith, JH Karam, JM TI W-coating for MEMS SO MICROMACHINING AND MICROFABRICATION PROCESS TECHNOLOGY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micromachining and Microfabrication Process Technology V CY SEP 20-22, 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 hard coating; tungsten; MEMS AB The integration of miniaturized mechanical components has spawned a new technology known as microelectromechanical systems (MEMS). Surface micromachining, defined as the fabrication of micromechanical structures from deposited thin films, is one of the core technological processes underlying MEMS. Surface micromachined structures have a large ratio of surface area to volume which makes them particularly vulnerable to adhesion to the substrate or adjacent structures during release or in use- a problem is called stiction. Since microactuators can have surfaces in normal or sliding contact, friction and wear are critical issues for reliable operation of MEMS devices. Surface modifications are needed to reduce adhesion and friction in micromechanical structures. In this paper, we will present a process used to selectively coat MEMS devices with Tungsten using a CVD (Chemical Vapor Deposition) process. We will discuss the effect of wet and vapor phase cleans along with different process variables. Endurance of the W coating is important, especially in applications where wear due to repetitive contacts with the film may occur. Further, tungsten is hard and chemically inert. Tungsten CVD is used in the integrated-circuit industry, which makes this approach manufacturable. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Mani, SS (reprint author), Sandia Natl Labs, POB 5800,MS 1084, Albuquerque, NM 87185 USA. NR 9 TC 6 Z9 6 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 0-8194-3471-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3874 BP 150 EP 157 DI 10.1117/12.361215 PG 8 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BP12R UT WOS:000084199900017 ER PT S AU Rajic, S Datskos, PG Datskou, I AF Rajic, S Datskos, PG Datskou, I BE Smith, JH Karam, JM TI Novel fabrication and simple hybridization of exotic material MEMS SO MICROMACHINING AND MICROFABRICATION PROCESS TECHNOLOGY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micromachining and Microfabrication Process Technology V CY SEP 20-22, 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 exotic materials; hybridization; MEMS; MOEMS; microsensors ID FOCUSED ION-BEAM AB Work in materials other than silicon for MEMS applications has typically been restricted to materials such as metals and not more "exotic" semiconductors. However, group III-V and IL-VI semiconductors form a very important and versatile collection of material and electronic parameter variables available to the MEMS and MOEMS designer. Thus, not only are the traditional mechanical material variables (thermal conductivity, thermal expansion, Young's modulus, etc.) available, but also chemical constituents can be varied in ternary and quaternary materials. This flexibility can be extremely important for bath friction and chemical compatibility issues for MEMS. In addition, the ability to continually vary the bandgap energy can be particularly useful for many electronics and infrared detection applications. However, there are two major obstacles associated with alternate semiconductor material MEMS. The first issue is the actual fabrication of non-silicon devices and the second impediment is communicating with these novel devices. We will describe an essentially material independent fabrication method that is amenable to most group III-V and II-VI semiconductors. This technique uses a combination of non-traditional direct write precision fabrication processes such as diamond turning, ion milling, laser ablation, etc. This type of deterministic fabrication approach lends itself to an almost trivial assembly process. We will also describe in detail the mechanical, electrical, and optical self-aligning hybridization technique used for these alternate material MEMS. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Rajic, S (reprint author), Oak Ridge Natl Lab, MS-8039, Oak Ridge, TN 37831 USA. NR 13 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 0-8194-3471-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3874 BP 188 EP 194 DI 10.1117/12.361221 PG 7 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BP12R UT WOS:000084199900021 ER PT J AU Mattigod, SV McGrail, BP AF Mattigod, SV McGrail, BP TI Estimating the standard free energy of formation of zeolites using the polymer model SO MICROPOROUS AND MESOPOROUS MATERIALS LA English DT Article DE polymer model; standard free energy of formation; thermodynamics of zeolite ID THERMODYNAMIC PROPERTIES; GIBBS ENERGIES; THERMOCHEMISTRY; STABILITY; MINERALS AB The standard free energies of formation of a number of zeolites were estimated using the polymer model developed previously for smectites by Sposito. The estimates made with the polymer model were on average within 19 kJ mol(-1) (0.28%) of the experimental values for zeolites; this compares with the values estimated by the methods of LaIglesia and Aznar and of Chermak and Rimstidt which differed from the experimental values on average by approximately 27 kJ mol(-1) (0.40%) and 32 kJ mol(-1) (0.47%) respectively. The values predicted by the polymer model for dehydrated zeolites were within 28 kJ mol(-1) (0.3%) of the experimental values, whereas the other two methods generate estimates of free energies of formation values that differed on average by 89 kJ mol(-1) (1.28%) and 107 kJ mol(-1) (1.59%) from the experimental values. These comparisons indicate that the polymer model, formulated specifically for a crass of silicate minerals such as zeolites, always typically provides a better estimate of the standard free energy values than general models for all silicate minerals which contain a number of ad hoc assumptions. Better estimates provided by the polymer model can be attributed to the principle that the free energy changes associated with the formation of condensation polymers, such as zeolites, are related principally with the free energy changes associated with the relative change in coordination of exchangeable cations as they transfer from reactant hydroxide sites to exchangeable sites. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Mattigod, SV (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 31 TC 11 Z9 12 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-1811 J9 MICROPOR MESOPOR MAT JI Microporous Mesoporous Mat. PD JAN PY 1999 VL 27 IS 1 BP 41 EP 47 DI 10.1016/S1387-1811(98)00228-5 PG 7 WC Chemistry, Applied; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 173VJ UT WOS:000079000200005 ER PT J AU Carrado, KA Xu, LQ AF Carrado, KA Xu, LQ TI Materials with controlled mesoporosity derived from synthetic polyvinylpyrrolidone-clay composites SO MICROPOROUS AND MESOPOROUS MATERIALS LA English DT Article DE composite; hectorite; mesoporosity; mesoporous material; polymer-clay; synthetic clay ID MOLECULAR-SIEVES; HYDROTHERMAL CRYSTALLIZATION; MECHANISM; FRAMEWORK; MCM-41 AB Mesoporous synthetic days (MSCs) are obtained when polymer-containing silicate gels are hydrothermally crystallized to form layered magnesium silicate hectorite clays containing polymers that are incorporated in situ. In this in situ technique, interlayer intercalation of different polymers over broad molecular weight and concentration ranges is achieved. The polymer loading of synthesized composites is determined by thermal analysis, and the basal spacing changes resulting from different levels of polymer intercalation are monitored by X-ray powder diffraction (XRD). In some cases, intercalation occurs to such a degree as to delaminate the layers and cause loss of stacking registry. Polyvinylpyrrolidone (PVP) of several average molecular weights ranging from 10 x 10(3)-1.3 x 10(6), in loadings varying from 10 to 20 wt.%, were used. The organic polymer template molecules were removed from synthetic polymer-clay complexes via calcination. Pore radii, surface areas and pore volumes of the resulting porous inorganic networks (MSCs) were then measured. A direct correlation between both PVP M(w) and polymer loading on the radius of the average pore was found, which varied from 21-45 Angstrom. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem 200, Argonne, IL 60439 USA. RP Carrado, KA (reprint author), Argonne Natl Lab, Div Chem 200, 9700 S Cass Ave, Argonne, IL 60439 USA. EM kcarrado@anl.gov NR 21 TC 38 Z9 40 U1 0 U2 16 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-1811 J9 MICROPOR MESOPOR MAT JI Microporous Mesoporous Mat. PD JAN PY 1999 VL 27 IS 1 BP 87 EP 94 DI 10.1016/S1387-1811(98)00275-3 PG 8 WC Chemistry, Applied; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 173VJ UT WOS:000079000200010 ER PT S AU Feddema, JT Christenson, TR AF Feddema, JT Christenson, TR BE Nelson, BJ Breguet, JM TI Parallel assembly of high aspect ratio microstructures SO MICROROBOTICS AND MICROASSEMBLY SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Microrobotics and Microassembly CY SEP 21-22, 1999 CL BOSTON, MA SP SPIE ID VISION AB In this paper, a prototype robotic workcell for the parallel assembly of LIGA components is described. A Cartesian robot is used to press 386 and 485 micron diameter pins into a LIGA substrate and then place a 3-inch diameter wafer with LIGA gears onto the pins. Upward and downward looking microscopes are used to locate holes in the LIGA substrate, pins to be pressed in the holes, and gears to be placed on the pins. This vision system can locate parts within 3 microns, while the Cartesian manipulator can place the parts within 0.4 microns. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800,MS 1003, Albuquerque, NM 87185 USA. NR 16 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 0-8194-3427-2 J9 PROC SPIE PY 1999 VL 3834 BP 153 EP 164 DI 10.1117/12.357819 PG 12 WC Automation & Control Systems; Engineering, Manufacturing; Optics SC Automation & Control Systems; Engineering; Optics GA BN92L UT WOS:000083488400017 ER PT S AU James, EM Browning, ND Xin, Y Reno, JL Baca, AG AF James, EM Browning, ND Xin, Y Reno, JL Baca, AG BE Cullis, AG Beanland, R TI Atomic resolution microscopy of semiconductor defects and interfaces SO MICROSCOPY OF SEMICONDUCTING MATERIALS 1999, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT Conference on Microscopy of Semiconducting Materials CY MAR 22-25, 1999 CL UNIV OXFORD, OXFORD, ENGLAND SP Inst Phys, Electron Microscopy & Analy Grp, Royal Microscop Soc, Mat Res Soc, Hitachi Sci Instruments Ltd, JEOL (UK) Ltd, FEI Ltd HO UNIV OXFORD AB The optical-arrangement of the scanning transmission electron microscope (STEM) allows formation of incoherent images by use of a large annular detector. Here we show this capability in the imaging of defects in GaN and the interfacial region of an Au/GaAs ohmic contact. A resolution of around 0.15 nm is attained. Such "Z-contrast" images show strong atomic number contrast and allow the probe to be positioned accurately at the defect or interface for the purpose of performing high spatial resolution electron energy-loss spectroscopy (EELS). C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP James, EM (reprint author), Univ Illinois, Dept Phys, 845 W Taylor St, Chicago, IL 60607 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0650-5 J9 INST PHYS CONF SER PY 1999 IS 164 BP 11 EP 14 PG 4 WC Materials Science, Characterization & Testing; Microscopy; Physics, Applied; Physics, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Microscopy; Physics GA BR57G UT WOS:000166835300002 ER PT S AU Norman, AG Olson, JM Geisz, JF Moutinho, HR Mason, A Al-Jassim, MM Vernon, SM AF Norman, AG Olson, JM Geisz, JF Moutinho, HR Mason, A Al-Jassim, MM Vernon, SM BE Cullis, AG Beanland, R TI Phase separation and facet formation during the growth of (GaAs)(1-x)(Ge-2)(x) alloy layers by metal organic vapour phase epitaxy SO MICROSCOPY OF SEMICONDUCTING MATERIALS 1999, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT Conference on Microscopy of Semiconducting Materials CY MAR 22-25, 1999 CL UNIV OXFORD, OXFORD, ENGLAND SP Inst Phys, Electron Microscopy & Analy Grp, Royal Microscop Soc, Mat Res Soc, Hitachi Sci Instruments Ltd, JEOL (UK) Ltd, FEI Ltd HO UNIV OXFORD ID MOLECULAR-BEAM EPITAXY; TANDEM SOLAR-CELLS; ELECTRON-DIFFRACTION; GAAS AB Metal organic vapour phase epitaxy (GaAs)(1-x)(Ge-2)(x) alloy layers, 0 emerged above 1.5x10(19) C+/m(2) (similar to 0.05 dpa in the near-surface region), which might be associated with the lattice disturbance in the crystal structure. A gradual decrease in half-angular width was observed with the increase of ion fluence in the experiment. The minimum yield exhibits a rather linear relationship with ion dose at the surface. Post-irradiation annealing at the irradiation temperature did not result in measurable recovery for fluences ranging from 4x10(18) to 2x10(19) C+/m(2) at 300, 470 and 670 K. Results also show that low fluence (<8x10(18) C+/m(2)) irradiation at 185 K followed by thermal annealing results in similar defect concentrations to irradiation at that same temperature to the same ion fluence. Thus, at low fluences, the accumulated defects are in thermal equilibrium with the structure. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Jiang, W (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 19 TC 3 Z9 3 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 183 EP 188 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500027 ER PT S AU Daulton, TL Lewis, RS Rehn, LE Kirk, MA AF Daulton, TL Lewis, RS Rehn, LE Kirk, MA BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Heavy-ion irradiation induced diamond formation in carbonaceous materials SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID HOMOGENEOUS NUCLEATION; GAS-PHASE; METEORITES; ONIONS; POWDER; FILMS AB Metastable phase formation under highly non-equilibrium thermodynamic conditions within high-energy particle tracks are investigated. In particular, the possible formation of diamond by heavy-ion irradiation of graphite at ambient temperature is examined. This work was motivated, in part, by an earlier study which discovered nanometer-grain polycrystalline diamond aggregates of submicron-size in uranium-rich carbonaceous mineral assemblages of Precambrian age. It was proposed that these diamonds were formed within the particle tracks produced in the carbonaceous minerals by the radioactive decay of uranium. To test the hypothesis that nanodiamonds can form by ion irradiation, fine-grain polycrystalline graphite sheets were irradiated with 400 MeV Kr ions to low fluence (6 x 10(12) ions-cm(-2)). Th, ion-irradiated(and unirradiated control) graphite were then subjected to acid dissolution treatments to remove the graphite and isolate any diamonds that were produced. These acid residues were characterized by transmission electron microscopy. The acid residue of the ion-irradiated graphite was found to contain nanodiamonds (at several ppm of bulk), demonstrating that ion irradiation of graphite at ambient temperature can produce diamond. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Daulton, TL (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 6 Z9 6 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 189 EP 194 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500028 ER PT S AU White, CW Meldrum, A Sonder, E Budai, JD Zuhr, RA Withrow, SP Henderson, DO AF White, CW Meldrum, A Sonder, E Budai, JD Zuhr, RA Withrow, SP Henderson, DO BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Formation of ZnAl2O4 and MgAl2O4 spinel in Al2O3 by ion implantation SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID SAPPHIRE AB ZnAl2O4 spinel has been formed in Al2O3 by ion implantation. Sequential implantation of Zn and O in overlapping profiles followed by annealing in Ar + H-2 gives rise to a nearly continuous epitaxial layer of ZnAl2O4 oriented with (111) planes parallel to (0001) planes of Al2O3. If only Zn is implanted, then discrete bands of ZnAl2O4 oriented with (422) planes parallel to (0001) planes of Al2O3 are produced. By similar methods, oriented MgAl2O4 spinel also has been produced in Al2O3 by sequential Mg + O implantation. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP White, CW (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 13 TC 6 Z9 6 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 219 EP 224 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500033 ER PT S AU Honda, S Modine, FA Meldrum, A Budai, JD Haynes, TE Boatner, LA Gea, LA AF Honda, S Modine, FA Meldrum, A Budai, JD Haynes, TE Boatner, LA Gea, LA BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Ion-implantation/annealing-induced precipitation of nanophase ferromagnetic particles in yttrium-stabilized ZrO2 SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc AB Ion implantation and thermal processing techniques have been used to form embedded ferromagnetic nanophase precipitates and thereby create magneto-optically active near-surface regions on otherwise inactive materials. Ferromagnetic precipitates were formed by first implanting Fe+ or Ni+ into Y0.15Zr0.85O1.93 (YSZ) with an implant energy of 140 keV, a fluence of 8.0 X 10(16) ions/cm(2), and at a temperature of-189 degrees C. After implantation, the specimens were annealed at temperatures ranging from 500 to 1100 degrees C in several types of reducing atmospheres. X-ray diffraction and TEM analysis of the Fe- or Ni-implanted/annealed specimens revealed that crystallographically coherent precipitates of metallic alpha-Fe, magnetite (Fe3O4), or Ni could be formed in YSZ depending on the annealing conditions. In particular, the cooling rate was established as the critical factor that determined whether Fe or Fe3O4 precipitates were created. Magneto-optical effects arising from ferromagnetic precipitates of Fe, Fe3O4, and Ni in the nearsurface region of YSZ were observed and characterized using magnetic circular dichroism (MCD). The magneto-optical response of the alpha-Fe, Fe3O4, and Ni precipitates was markedly different as indicated by the MCD-detected hysteresis curves. The precipitation mechanism, the chemical nature of the precipitates, and the particle-size distributions resulting from different annealing conditions were investigated and correlated with the precipitate magneto-optical properties. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Honda, S (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Haynes, Tony/P-8932-2015; Boatner, Lynn/I-6428-2013; Budai, John/R-9276-2016 OI Haynes, Tony/0000-0003-2871-4745; Boatner, Lynn/0000-0002-0235-7594; Budai, John/0000-0002-7444-1306 NR 4 TC 15 Z9 15 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 225 EP 230 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500034 ER PT S AU Yan, Y Walther, T Kirk, MA AF Yan, Y Walther, T Kirk, MA BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Measurement of oxygen disorder and nano-twin microstructure associated with columnar defects in YBCO SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc AB Studies of defects generated by high energy (>1 GeV) heavy ion irradiation in high-Tc superconductors have been performed by transmission electron microscopy (TEM). Our study shows that high dose irradiation leads to the formation of nano-twins, by which the columnar defects are connected. An analysis of the local Fourier components of the image intensity in [001] lattice images indicates that these new "twin" boundaries are much more diffuse than preexisting twin boundaries in YBCO. The mechanism of the formation of nano-twin boundaries on {110} planes and their possible relation to superconducting properties are discussed. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Yan, Y (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Walther, Thomas/C-2968-2012 OI Walther, Thomas/0000-0003-3571-6263 NR 8 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 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 267 EP 272 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500041 ER PT S AU Snead, LL Lara-Curzio, E AF Snead, LL Lara-Curzio, E BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Interphase integrity of neutron irradiated SiC composites SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID SILICON-CARBIDE; RADIATION AB SiC/SiC composites were fabricated from Hi-Nicalon(TM) fibers with carbon, porous SiC and multilayer SiC interphases. These materials were then irradiated in the High Flux Beam Reactor with fast neutrons at 260 and 900-1060 degrees C to a dose of 1.1x10(25) n/m(2) corresponding to 1.1 displacements per atom (dpa). Results are presented for bend strength of both non-irradiated and irradiated materials. Within the interphases studied the multilayer SIC interphase material showed the least degradation (8-20%) in ultimate bend stress, while porous SiC underwent the greatest degradation (similar to 35%). The fiber matrix interphases are studied with TEM for both nonirradiated and irradiated materials. While no irradiation induced microstructural evolution of the interphase was observed, debonding of the interphase from the fiber was observed for all cases. This debonding is attributed to tensile stresses developed at the interface due to densification of the Hi-Nicalon(TM) fiber. Residual stress analysis of the fiber matrix interface indicates that the irradiation-induced densification of Hi-Nicalon(TM) and the volumetric expansion of the CVD SiC matrix cause tensile stresses well in excess of those which can be withstood by these, or any other viable SiC composite interphase. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Snead, LL (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37830 USA. EM SneadLL@ornl.gov NR 17 TC 5 Z9 5 U1 0 U2 0 PU MATERIALS RESEARCH SOC PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 273 EP 278 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500042 ER PT S AU Zinkle, SJ Matzke, H Skuratov, VA AF Zinkle, SJ Matzke, H Skuratov, VA BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Microstructure of swift heavy ion irradiated MgAl2O4 spinel SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID MAGNESIUM ALUMINATE SPINEL; RADIATION-DAMAGE; SPECTRUM; DEFECT; AMORPHIZATION; CERAMICS; BEAM; EVOLUTION; SAPPHIRE; TRACKS AB Plan view and cross-section transmission electron microscopy was used to investigate the microstructure of magnesium aluminate spinel (MgAl2O4) following room temperature irradiation with either 430 MeV Kr, 614 MeV Xe, or 72 MeV I ions. The fluences ranged from 1x10(16)/m(2) (single track regime) to 1x10(20)/m(2). Destruction of the ordered spinel crystal structure on both the anion and cation sublattices was observed in the ion tracks at low fluences. At intermediate fluences, the overlapping ion tracks induced the formation of a new metastable crystalline phase. Amorphization with a volumetric expansion of similar to 35% was observed in spinel irradiated with swift heavy ions (electronic stopping powers >7 keV/nm) at fluences above 1x10(19)/m(2). These results demonstrate that swift heavy ion radiation can induce microstructural changes not achievable with conventional elastic collision irradiation at comparable temperatures. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Zinkle, SJ (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 27 TC 37 Z9 37 U1 2 U2 8 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 299 EP 304 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500045 ER PT S AU Zinkle, SJ Snead, LL Eatherly, WS Jones, JW Hensley, DK AF Zinkle, SJ Snead, LL Eatherly, WS Jones, JW Hensley, DK BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Effect of low temperature ion irradiation on the microstructure of nitride ceramics SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID SILICON-NITRIDE; INDUCED AMORPHIZATION; ELECTRON-IRRADIATION; BOMBARDMENT; SPECTRUM; CARBIDE; ALN AB Cross-section transmission electron microscopy was used to investigate the microstructure of polycrystalline silicon nitride (Si3N4) and aluminum nitride (AlN) following 2 MeV Si ion irradiation at 80 and 400 K up to a fluence of 4x10(20) ions/m(2) (maximum damage of similar to 10 displacements per atom, dpa). A buried amorphous band was observed at both temperatures in Si3N4 in the region corresponding to the peaks in the implanted ion and displacement damage. From a comparison of Si3N4 specimens irradiated at different fluences, it is concluded that the amorphization is primarily controlled by the implanted Si concentration rather than the displacement damage level. Si3N4 amorphization did not occur in regions well-separated from the implanted ions for doses up to at least 3 dpa at 80 K, whereas amorphization occurred in the ion implanted region (calculated Si concentration >0.01 at.%) for damage levels as low as similar to 0.6 dpa. The volumetric swelling associated with the amorphization of Si3N4 is <10%. Amorphization was not observed in any of the irradiated AlN specimens. A moderate density of small (similar to 3 nm) defect clusters were observed in the crystalline damaged regions of both the Si3N4 and AW specimens at both irradiation temperatures. Aligned network dislocations were also observed in the AlN specimen irradiated to high dose at 80 K. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Zinkle, SJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. EM zinklesj@ornl.gov; zinklesj@ornl.gov RI Hensley, Dale/A-6282-2016; OI Hensley, Dale/0000-0001-8763-7765; Zinkle, Steven/0000-0003-2890-6915 NR 26 TC 8 Z9 8 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 305 EP 310 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500046 ER PT S AU Chen, XD Birtcher, RC AF Chen, XD Birtcher, RC BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Bubble formation and growth in glasses SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc AB In this study, we simulated gas bubble formation in glasses by in-situ ion implantation. Alkali silicate glass and Na-borosilicate glass were implanted in situ with 50 keV Xe ions at temperatures at 200 degrees C in a Hitachi-9000 electron microscope. Bubble formation was studied by transmission electron microscopy images taken during interruptions of the ion beam after discrete implanted-ion dose steps. We present a possible mechanism of bubble formation and growth based on amorphous network structures. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Chen, XD (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Donnelly, Stephen/0000-0002-9749-5550 NR 6 TC 2 Z9 2 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 331 EP 336 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500050 ER PT S AU Fortner, JA Badyal, Y Price, DCL Hanchar, JM Weber, WJ AF Fortner, JA Badyal, Y Price, DCL Hanchar, JM Weber, WJ BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Structural analysis of a completely amorphous Pu-238-doped zircon by neutron diffraction SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID CERAMIC WASTE FORMS; PU-DOPED GLASS; AMORPHIZATION; ACTINIDES; PLUTONIUM AB The structure of a completely amorphous zircon was determined by time-of-flight neutron diffraction at Argonne's Intense Pulsed Neutron Source (IPNS). The sample of metamict zircon (ZrSiO4), initially doped to 8.85 weight percent Pu-238, had been completely amorphized by alpha-recoil damage since its synthesis in 1981 at the Pacific Northwest National Laboratory (PNNL). The measured diffraction structure factor, S(Q), indicated a completely amorphous sample, with no signs of residual zircon microcrystallinity. The pair distribution function obtained indicated that the structure was that of an oxide glass, retaining the Si-O, Zr-O, and O-O bond lengths of crystalline zircon. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Fortner, JA (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Weber, William/0000-0002-9017-7365 NR 16 TC 4 Z9 4 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 349 EP 353 PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500053 ER PT S AU Weber, MJ Devanathan, R Meldrum, A Boatner, LA Ewing, RC Wang, LM AF Weber, MJ Devanathan, R Meldrum, A Boatner, LA Ewing, RC Wang, LM BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI The effect of temperature and damage energy on amorphization in zircon SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID DECAY-INDUCED AMORPHIZATION; PHASE; IRRADIATION; PLUTONIUM C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Weber, MJ (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Boatner, Lynn/I-6428-2013; OI Boatner, Lynn/0000-0002-0235-7594; Devanathan, Ram/0000-0001-8125-4237; Weber, William/0000-0002-9017-7365 NR 26 TC 11 Z9 12 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 367 EP 372 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500056 ER PT S AU Thevuthasan, S Jiang, W Weber, WJ McCready, DE AF Thevuthasan, S Jiang, W Weber, WJ McCready, DE BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Damage accumulation and thermal recovery in SrTiO3 implanted with Au2+ ions SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID BEAM-AMORPHIZED SRTIO3; EPITAXIAL RECRYSTALLIZATION AB Damage accumulation and recovery process have been investigated in single crystal (2+) using in-situ Rutherford Backscattering Spectrometry SrTiO3 irradiated with 1.0 MeV An (RBS) in Channeling geometry Samples were irradiated at a temperature of 200 K with ion fluences ranging from 5.0x10(13) - 2.5x10(14) Au2+/cm(2) (0.22 - 1.10 dpa at damage peak). Subsequent isochronal annealing experiments were performed to study damage recovery processes up to a maximum temperature of 870 K. At an ion fluence between 2.0-2.5x10(14) Au2+/cm(2) (0.88 - 1.10 dpa), the implanted region, which is just below the surface, becomes amorphous. The recovery processes occur over a broad temperature range, and the damage created by low ion fluences, 5.0x10(13) - 1.0x10(14) Au2+/cm(2), is almost completely recovered after annealing at 870 K. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Thevuthasan, S (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 9 TC 2 Z9 2 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 373 EP 378 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500057 ER PT S AU Song, J Corrales, LR Jonsson, H AF Song, J Corrales, LR Jonsson, H BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Exploring the excited states of vacancy defects in silica SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID MOLECULAR-DYNAMICS; SIO2; METALS; MODEL AB A study of vacancy defect formation is carried out using a density functional theory molecular dynamics simulation methodology. The objective is to study the effects of electronic excitations in crystalline and non-crystalline silica polymorphs. We present an initial study focusing on the formation energetics of distinct oxygen vacancy defect states in alpha-quartz. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Corrales, LR (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 9 TC 2 Z9 2 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 379 EP 382 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500058 ER PT S AU Meldrum, A Zinkle, SJ Boatner, LA Wu, M Mu, R Ueda, A Henderson, DO Ewing, RC AF Meldrum, A Zinkle, SJ Boatner, LA Wu, M Mu, R Ueda, A Henderson, DO Ewing, RC BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Radiation effects in zircon, hafnon, and thorite: Implications for Pu disposal SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID PLUTONIUM; CERAMICS; DAMAGE; PHASE AB Synthetic ZrSiO4, HfSiO4, and ThSiO4 single-crystal specimens were irradiated by 800 keV Kr+ ions, and the microstructural evolution was observed in-situ in a transmission electron microscope. All three compounds were found to become amorphous up to temperatures in excess of 600 degrees C. Using a new model, the activation energies for annealing were found to be in the range of 3.1 to 3.6 eV for these compounds. At temperatures above 600 degrees C, the orthosilicates were observed to decompose into the component oxides (e.g., tetragonal ZrO2 + amorphous SiO2 in the case of zircon). A single-crystal zircon specimen was also irradiated with a pulsed picosecond Nd:YAG laser operated at 355 nm, and the resulting microstructure was investigated by optical absorption, SEM, AFM, and TEM techniques. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Meldrum, A (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Boatner, Lynn/I-6428-2013; OI Boatner, Lynn/0000-0002-0235-7594; Zinkle, Steven/0000-0003-2890-6915 NR 11 TC 1 Z9 1 U1 0 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 395 EP 400 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500061 ER PT S AU Alexander, DE Kestel, BJ Jemian, PR Odette, GR Klingensmith, D Gragg, D AF Alexander, DE Kestel, BJ Jemian, PR Odette, GR Klingensmith, D Gragg, D BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Anomalous small-angle x-ray scattering characterization of model pressure vessel alloy microstructures SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID FECU BINARY-ALLOYS; ELECTRON-IRRADIATION; PRECIPITATION AB Anomalous small-angle x-ray scattering (ASAXS) experiments were performed at energies near the Mn-K and Fe-K absorption edges on an Fe-0.9 Cu wt.%-1.0 Mn wt.% alloy subjected to either annealing at 450 degrees C, 24 hrs or irradiation with 10 MeV electrons to 0.5 mdpa at 300 degrees C. A Guinier analysis of the net scattered intensity revealed scatterers with radii of 16.5-16.8 Angstrom and 16.4-17.3 Angstrom; for the irradiated and annealed foils, respectively. The variation in net scattered intensity with photon energy in the annealed sample was consistent with scattering contrast variations expected for Cu-rich, Cu-Mn precipitates. Minimal variation in net intensity (scattering contrast) with energy determined that Cu-Mn precipitates were not detected in the irradiated sample. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Alexander, DE (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 9 TC 5 Z9 5 U1 1 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 415 EP 420 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500064 ER PT S AU Cole, JI Allen, TR AF Cole, JI Allen, TR BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI The effect of low dose-rate irradiation on the microstructure of 304 stainless steel SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID EVOLUTION AB Changes in mechanical and corrosion properties caused by the development of radiation-induced microstructures have relevance to the aging and lifetime extension of light water reactors (LWR's). However, much of the current data related to microstructural development in irradiated metals are generated from studies carried out at much higher dose-rates than encountered in LWR's. An opportunity exists to study the influence of low dose-rate irradiation on microstructural development for a variety of structural and surveillance materials extracted from the experimental breeder reactor EBR-II. In this study, irradiated 304 stainless steel hexagonal "hex" duct material is examined in order to compare microstructures in the dose-rate range of 10(-7) 10(-9) dpa/sec. The samples, taken from the reflector locations in EER-II, experienced a total dose between 10 and 12 dpa at a temperature of similar to 375 degrees C. Transmission electron microscopy (TEM) analysis reveals that there is a moderate dose-rate effect on microstructural development for samples irradiated in the range of 2 x 10(-8) to 4 x 10(-8) dpa/sec, however a substantial dose-rate effect exists between dose-rates of 2 x 10(-8) and 1 x 10(-9) dpa/sec Results detail the development of the microstructure in terms of radiation-induced cavities, dislocations, and precipitates. C1 Argonne Natl Lab, Idaho Falls, ID 83403 USA. RP Cole, JI (reprint author), Argonne Natl Lab, W POB 2528, Idaho Falls, ID 83403 USA. OI Allen, Todd/0000-0002-2372-7259; Cole, James/0000-0003-1178-5846 NR 10 TC 2 Z9 2 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 433 EP 438 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500066 ER PT S AU Kenik, EA Busby, JT Miller, MK Thuvander, AM Was, G AF Kenik, EA Busby, JT Miller, MK Thuvander, AM Was, G BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Origin and influence of pre-existing segregation on radiation-induced segregation in austenitic stainless steels SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc AB The pre-existing segregation at grain boundaries in two austenitic stainless steels has been investigated by atom probe field ion microscopy and analytical electron microscopy. In addition, the effect of radiation-induced segregation on the near-grain-boundary composition has been studied by analytical electron microscopy. Pre-existing enrichment of Cr, Mo, B, C and P and depletion of Fe and Ni near grain boundaries has been observed. Significant affinity between Mo and N in both alloys is indicated by the detection of MoN2+ molecular ions during field evaporation. The pre-existing segregation is modified by radiation-induced segregation resulting in Ni and Si enrichment near the boundary as well as depletion of chromium adjacent to the boundary resulting in a "W-shaped" Or profile. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Kenik, EA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 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 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 445 EP 450 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500068 ER PT S AU Dimelfi, RJ Alexander, DE Rehn, LE AF Dimelfi, RJ Alexander, DE Rehn, LE BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Modeling the post-yield flow behavior after neutron and electron irradiation of steels and iron-base alloys SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc AB Irradiation hardening is an issue of practical importance as it relates to the remanent life and the nature of failure of reactor components exposed to displacement-producing radiation. Understanding these phenomena requires studies of fundamental microstructural mechanisms of hardening. In this paper, we analyze the tensile behavior of pressure vessel steels (A212B and A350) irradiated by neutrons and electrons. The results show that the post-yield true stress/true strain behavior can provide fingerprints of the different hardening effects that result from irradiation by the two particles, which suggests correspondingly different hardening microstructures for the two particles. Microstructurally-based models for irradiation-induced yield strength increases, combined with a model for strain hardening, are used to make predictions of the different effects of irradiation by the two particles on the entire flow curve that agree well with data. C1 Argonne Natl Lab, Reactor Engn Div, Argonne, IL 60439 USA. RP Dimelfi, RJ (reprint author), Argonne Natl Lab, Reactor Engn Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 22 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 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 463 EP 469 PG 7 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500071 ER PT S AU Kameda, J Bloomer, TE AF Kameda, J Bloomer, TE BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Post-irradiation annealing and intergranular segregation and desegregation SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID ALLOYS; MODEL AB The effect of post-irradiation annealing (PIA: at 573-958 K for 0.1-1000 h) on the intergranular S and P segregation has been examined in ferritic alloys doped with Cu and/or P, all containing residual S. In a Cu-doped alloy showing no P segregation, the rate and amount of segregated S were promoted more by PIA than thermal annealing. Intergranular P enrichment was observed during an early PIA stage at lower temperatures in P-containing alloys. The intergranular P desegregation and S segregation concurrently occurred at higher PIA temperatures. By applying a modified McLean theory, it is shown that the S segregation in the post-irradiation annealed Cu-doped alloy is controlled by vacancy-enhanced diffusion while the P segregation in P-containing alloys subjected to lower temperature PIA proceeds via mobile P-interstitial complexes. Based on a Gaussian relaxation model, the P desegregation during prolonged PIA at higher temperatures is assisted by the formation and migration of vacancies. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Kameda, J (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 14 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 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 477 EP 482 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500073 ER PT S AU Simonen, EP Bruemmer, SM AF Simonen, EP Bruemmer, SM BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Cr-vacancy elastic and chemical interactions in irradiated stainless steels SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID GRAIN-BOUNDARY SEGREGATION; SOLUTE SEGREGATION; ALLOYS AB Interactions between point defects and major solute strongly influence grain boundary concentrations during heat treatment, irradiation and annealing of austenitic stainless steels. Previous approaches to nonequilibrium segregation emphasize only elastic defect-solute interactions. The present evaluation of nonequilibrium concentrations at grain boundaries indicates chemical interactions unique to solution annealing and cooling during thermal nonequilibrium segregation (TNES). Subsequent to TNES, radiation-induced segregation and post-irradiation annealing are modeled and compared with measured changes in grain boundary composition. The latter two mechanisms are controlled by exchanges between vacancies and major solute such as Cr. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Simonen, EP (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999,P8-15, Richland, WA 99352 USA. NR 18 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 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 501 EP 506 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500077 ER PT S AU Kirk, MA Jenkins, ML Fukushima, H AF Kirk, MA Jenkins, ML Fukushima, H BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI The search for interstitial dislocation loops produced in displacement cascades at 20K in copper SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID TRANSMISSION ELECTRON-MICROSCOPY; MOLECULAR-DYNAMICS; DAMAGE; IRRADIATION; CLUSTERS AB A low-temperature in situ ion-irradiation and annealing experiment has been performed by TEM in copper. Most defect clusters which persisted through an anneal to 120 K showed no size changes within the resolution (0.5 nm) of a new weak-beam sizing technique. Of 55 defects measured under a range of weakly diffracting conditions, 7 showed measurable size decreases while 3 showed size increases. We argue that these clusters are likely to be of vacancy and interstitial nature, respectively. Also on annealing to 120 K a fraction of about 25% of the clusters formed by irradiation with 600 kV Cu+ ions at 20 K disappeared, while a similar number of clusters appeared in different locations. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Kirk, MA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 1 Z9 1 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 521 EP 526 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500080 ER PT S AU Allen, CW McCormick, AW Kestel, BJ Baldo, PM Zaluzec, NJ Rehn, LE AF Allen, CW McCormick, AW Kestel, BJ Baldo, PM Zaluzec, NJ Rehn, LE BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Fabrication of a simple materials system for study of Hg in a stainless steel SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID SITU ION-BEAM; ARGONNES AB The Spallation Neutron Source (SNS), currently under construction at Oak Ridge National Laboratory, is expected to employ a Hg target encased in a stainless steel. Little is known about the metallurgical behavior of this materials engineering system, which will occur in a service environment involving elevated temperatures and intense radiation. Under normal equilibrium conditions, however, Hg is known to be insoluble in and non-reactive with solid Fe and Or but to form one or more intermetallics with Ni. Hg has been implanted into alloy 304L. After implantations at 400 and 500 degrees C to a fluence of 3x10(16) cm(-2) sub-micron sized precipitates of Hg are formed, as judged, for example, from their solidification behavior on cooling during TEM observation. The formation of such a system of microtargets and possible studies employing them as in situ TEM specimens are discussed, which can provide useful empirical information in conjunction with SNS target development. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Allen, CW (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 5 TC 2 Z9 2 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 561 EP 566 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500086 ER PT S AU Birtcher, RC Donnelly, SE AF Birtcher, RC Donnelly, SE BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Craters produced on metals by single ion impacts SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID IRRADIATION; GOLD C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Birtcher, RC (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Donnelly, Stephen/0000-0002-9749-5550 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 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 579 EP 584 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500089 ER PT S AU Rest, J Hofman, GL Konovalov, II Maslov, AA AF Rest, J Hofman, GL Konovalov, II Maslov, AA BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Effect of formation and growth of dislocation loops and cavities on low-temperature swelling of irradiated uranium-molybdenum alloys SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID FUEL AB Scanning electron photomicrographs of U-IO wt.% Mo irradiated at low temperature in the Advanced Test Reactor (ATR) to about 40 at.% burnup show the presence of cavities. We have used a rate-theory-based model to investigate the nucleation and growth of cavities during low-temperature irradiation of uranium-molybdenum alloys in the presence of irradiation-induced interstitial-loop formation and growth. Our calculations indicate that the swelling mechanism in the U-10 wt.% Mo alloy at low irradiation temperatures is fission-gas driven. The calculations also indicate that the observed bubbles must be associated with a subgrain structure. Calculated bubble-size-distributions are compared with irradiation data. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Rest, J (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 8 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 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 609 EP 614 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500094 ER PT S AU Stoller, RE Greenwood, LR AF Stoller, RE Greenwood, LR BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI From molecular dynamics to kinetic rate theory: A simple example of multiscale modeling SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID PRIMARY DAMAGE FORMATION; DISPLACEMENT CASCADES; METALS; IRON AB Radiation damage formation in iron has been investigated using the method of molecular dynamics simulation. The MD simulations have been used to determine primary defect production parameters for cascade energies up to 50 keV at temperatures from 100 to 900K. The energy dependence of these parameters has been used to determine appropriate neutron-energy-spectrum averaged damage production cross sections for various irradiation environments. Two applications of these effective cross sections are discussed. The first is an evaluation of neutron energy spectrum effects in commercial fission reactor pressure vessels. The second example deals with the use of these cross sections in the source term of a kinetic model used to predict void swelling and microstructural evolution. The simulation of the primary damage event by MD involves times less than 100 ps and a size scale of a few tens of nm, while the kinetic simulation encompasses several years and macroscopic sizes. This use of the MD results to develop an improved source term for rate theory modeling provides a simple example of multiscale modeling. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Stoller, RE (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Stoller, Roger/H-4454-2011; Greenwood, Lawrence/H-9539-2016 OI Greenwood, Lawrence/0000-0001-6563-0650 NR 19 TC 1 Z9 1 U1 0 U2 6 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 629 EP 636 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500096 ER PT S AU Alexander, DE AF Alexander, DE BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Exploring the use of pulsed irradiations for studying the transient sink formed by cascade producing radiation SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID ION AB An approach is suggested for using pulsed irradiation experiments to study attributes of the transient sink formed by cascade producing radiation. As an example, a simple model of radiation enhanced diffusion is proposed for a dual ion beam irradiation in which one of the beams is a pulsed, sink-producing heavy ion. It is demonstrated that by combining this model with diffusivity measurements evaluated as a function of the irradiation pulse wavelength, it is possible to quantitatively determine the transient sink strength and its characteristic lifetime. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Alexander, DE (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 MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 673 EP 678 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500103 ER PT S AU Stoller, RE AF Stoller, RE BE Zinkle, SJ Lucas, GE Ewing, RC Williams, JS TI Point defect cluster formation in iron displacement cascades up to 50 keV SO MICROSTRUCTURAL PROCESSES IN IRRADIATED MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Microstructural Processes in Irradiated Materials, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID PRIMARY DAMAGE FORMATION; MOLECULAR-DYNAMICS; ALPHA-IRON; METALS AB The results of molecular dynamics displacement cascade simulations in iron at energies up to 50 keV and temperatures of 100, 600, and 900K are summarized, with a focus on the characterization of interstitial and vacancy clusters that are formed directly within the cascade. The fraction of the surviving point defects contained in clusters, and the size distributions of these in-cascade clusters have been determined. Although the formation of true vacancy clusters appears to be inhibited in iron, a significant degree of vacancy site correlation was observed. These well correlated arrangements of vacancies can be considered nascent clusters, and they have been observed to coalesce during longer term Monte Carlo simulations which permit short range vacancy diffusion. Extensive interstitial clustering was observed. The temperature and cascade energy dependence of the cluster size distributions are discussed in terms of their relevance to microstructural evolution and mechanical property changes in irradiated iron-based alloys. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Stoller, RE (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Stoller, Roger/H-4454-2011 NR 14 TC 3 Z9 3 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-446-7 J9 MATER RES SOC SYMP P PY 1999 VL 540 BP 679 EP 684 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology SC Materials Science; Metallurgy & Metallurgical Engineering; Nuclear Science & Technology GA BN10Y UT WOS:000080728500104 ER PT S AU de Boer, MP Knapp, JA Mayer, TM Michalske, TA AF de Boer, MP Knapp, JA Mayer, TM Michalske, TA BE Gorecki, C TI The role of interfacial properties on MEMS performance and reliability SO MICROSYSTEMS METROLOGY AND INSPECTION SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Microsystems Metrology and Inspection CY JUN 15-16, 1999 CL MUNICH, GERMANY SP European Opt Soc, SPIE, Commiss European Communities, Directorate Gen Sci, Res & Dev, Wissenschaftliche Gesell Lasertech eV ID SELF-ASSEMBLED MONOLAYERS; SOLID-LIQUID INTERFACE; SILICON; POLYSILICON; ADHESION; FILMS; OCTADECYLTRICHLOROSILANE; TEMPERATURE; SURFACES; GLASS AB We have constructed a humidity-controlled chamber in which deflections of polysilicon cantilever beams are observed by interferometry, resulting in in-situ adhesion measurements within a fracture mechanics framework. From adhesion energy measurements for uncoated hydrophilic beams, we demonstrate an exponential dependence of adhesion on relative humidity (RH). We can explain this trend with a single-asperity model for capillary condensation. For coated hydrophobic beams, adhesion is independent of RH up to a threshold value which depends on the coating used. However, we have found that exposure to very high RH (greater than or equal to 90%) ambients can cause a dramatic increase in adhesion, surprisingly with a stronger effect for perfluorodecyltrichlorosilane (FDTS, C(10)H(4)F(17)SiCl(3)) than octadecyltrichlorosilane (ODTS, C(18)H(37)SiCl(3)). Newly developed computational mechanics to measure adhesion in the presence of an applied load allow us to explore how the adhesion increase develops. We believe that water adsorption at silanol sites at the FDTS/substrate interface, Possibly exacerbated by coupling agent migration, leads to water islanding and the subsequent adhesion increase at very high RH levels. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP de Boer, MP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 49 TC 31 Z9 31 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 0-8194-3311-X J9 PROC SPIE PY 1999 VL 3825 BP 2 EP 15 DI 10.1117/12.364289 PG 14 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Optics; Physics, Applied SC Engineering; Instruments & Instrumentation; Optics; Physics GA BN80S UT WOS:000082991800001 ER PT B AU Smoot, GF AF Smoot, GF BE DeOliveiraCosta, A Tegmark, M TI CMB synchrotron foreground SO MICROWAVE FOREGROUNDS SE Astronomical Society of the Pacific Conference Series LA English DT Proceedings Paper CT Workshop on Microwave Foregrounds CY NOV 14-15, 1998 CL INST ADV STUDY, PRINCETON, NJ SP Alfred P Sloan Fdn HO INST ADV STUDY ID GALACTIC EMISSION; RADIO-EMISSION; FREQUENCIES; RADIATION; POLARIZATION; MAPS; GHZ; MHZ AB Synchrotron emission is an important process in Galactic dynamics and a potentially confusing foreground for cosmic microwave background (CMB) radiation observations, Though the mechanism of synchrotron emission is well understood, the details for the Galaxy and many external sources is not well characterized. Quality maps at multiple frequencies are lacking but needed for a, full understanding of the Galactic synchrotron emission: including intensity, spectrum, and spectral variation, At high frequencies (> 70 GHz) synchrotron emission is not a severe limitation to precise CMB observations well away from the Galactic plane. C1 Univ Calif Berkeley, LBNL, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, LBNL, Berkeley, CA 94720 USA. NR 42 TC 9 Z9 9 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-006-4 J9 ASTR SOC P PY 1999 VL 181 BP 61 EP 75 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN98N UT WOS:000083761100002 ER PT B AU Haiman, Z Knox, L AF Haiman, Z Knox, L BE DeOliveiraCosta, A Tegmark, M TI Reionization of the intergalactic medium and its effect on the CMB SO MICROWAVE FOREGROUNDS SE Astronomical Society of the Pacific Conference Series LA English DT Proceedings Paper CT Workshop on Microwave Foregrounds CY NOV 14-15, 1998 CL INST ADV STUDY, PRINCETON, NJ SP Alfred P Sloan Fdn HO INST ADV STUDY ID MICROWAVE BACKGROUND ANISOTROPIES; LY-ALPHA FOREST; HIGH-REDSHIFT; BLACK-HOLES; GALAXY FORMATION; UNIVERSE; FLUCTUATIONS; QUASARS; PHOTOIONIZATION; CONSTRAINTS AB The bulk of the hydrogen in the universe transformed from neutral to ionized somewhere in the redshift interval 5 less than or similar to z less than or similar to 40 most likely due to ionizing photons produced by an early generation of stars or mini-quasars. The resulting free electrons, interacting with the CMB photons via Thomson-scattering, are a mixed blessing, providing both a probe of the epoch of the first stars and a contaminant,nt to the pristine primary anisotropy. Here we review our current knowledge of reionization with emphasis on inhomogeneities and describe the possible connections to CMB anisotropy. C1 Fermilab Natl Accelerator Lab, NASA Fermilab Astrophys Ctr, Batavia, IL 60510 USA. RP Fermilab Natl Accelerator Lab, NASA Fermilab Astrophys Ctr, POB 500, Batavia, IL 60510 USA. NR 85 TC 29 Z9 29 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-006-4 J9 ASTR SOC P PY 1999 VL 181 BP 227 EP 250 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN98N UT WOS:000083761100012 ER PT S AU Fleming, JG Lin, SY AF Fleming, JG Lin, SY BE Motomedi, ME Goering, R TI 3-D silicon photonic lattices - cornerstone of an emerging photonics revolution SO MINIATURIZED SYSTEMS WITH MICRO-OPTICS AND MEMS SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Miniaturized Systems with Micro-Optics and MEMS CY SEP 20-22, 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; OPTICAL WAVELENGTHS; CRYSTAL 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 Sandia Natl Labs, POB 5800,Org 1723,MS 1084, Albuquerque, NM 87185 USA. NR 24 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 0-8194-3475-2 J9 PROC SPIE PY 1999 VL 3878 BP 9 EP 18 DI 10.1117/12.361218 PG 10 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BP12U UT WOS:000084201000002 ER PT S AU Krygowski, TW Reyes, D Rodgers, MS Smith, JH Warren, M Sweatt, W Blum-Spahn, O Wendt, JR Asbill, R AF Krygowski, TW Reyes, D Rodgers, MS Smith, JH Warren, M Sweatt, W Blum-Spahn, O Wendt, JR Asbill, R BE Motomedi, ME Goering, R TI Development of a compact optical-MEMS scanner with integrated VCSEL light source and diffractive optics SO MINIATURIZED SYSTEMS WITH MICRO-OPTICS AND MEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Miniaturized Systems with Micro-Optics and MEMS CY SEP 20-22, 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 OMEMS; MEMS scanner; VCSEL; hybrid package; substrate-mode architecture; Diffractive Optical Element AB In this work the design and initial fabrication results are reported for the components of a compact optical-MEMS laser scanning system. This system integrates a silicon MEMS laser scanner, a Vertical Cavity Surface Emitting Laser (VCSEL) and passive optical components. The MEMS scanner and VCSEL are mounted onto a fused silica substrate which serves as an optical interconnect between the devices. Two Diffractive Optical Elements (DOE's) are etched into the fused silica substrate to focus the VCSEL beam and increaase the scan range. The silicon MEMS scanner consists of an actuator that continuously scans the position of a large polysilicon gold-coated shuttle containing a third DOE. Interferometric measurements show that the residual stress in the 500 mu m x 1000 mu m shuttle is extremely low, with a maximum deflection of only 0.18 mu m over an 800 mu m span for an unmetallized case and a deflection of 0.56 mu m for the metallized case. A conservative estimate for the scan range is similar to +/-4 degrees with a spot size of about 0.5 mm, producing 50 resolvable spots. The basic system architecture, optical and MEMS design is reported in this paper, with an emphasis on the design and fabrication of the silicon MEMS scanner portion of the system. C1 Sandia Natl Labs, Microelect Dev Lab, Livermore, CA 94550 USA. RP Krygowski, TW (reprint author), Sandia Natl Labs, Microelect Dev Lab, Livermore, CA 94550 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 0-8194-3475-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3878 BP 20 EP 28 DI 10.1117/12.361250 PG 9 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BP12U UT WOS:000084201000003 ER PT S AU Warren, ME Sweatt, WC Wendt, JR Bailey, CG Matzke, CM Arnold, DW Kemme, SA Allerman, AA Carter, TR Asbill, RE Samora, S AF Warren, ME Sweatt, WC Wendt, JR Bailey, CG Matzke, CM Arnold, DW Kemme, SA Allerman, AA Carter, TR Asbill, RE Samora, S BE Motomedi, ME Goering, R TI Integrated micro-optical fluorescence detection system for microfluidic electrochromatography SO MINIATURIZED SYSTEMS WITH MICRO-OPTICS AND MEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Miniaturized Systems with Micro-Optics and MEMS CY SEP 20-22, 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 micro-optics; fluorescence; VCSEL; electrochromatography; diffractive optics; substrate-mode; microfluidics; chemical sensing ID CAPILLARY-ELECTROPHORESIS; FABRICATION; SEPARATIONS; TECHNOLOGY; CHIP; DNA AB We describe the design and microfabrication of an extremely compact optical system as a key element in an integrated capillary-channel electrochromatograph with laser induced fluorescence detection. The optical design uses substrate-made propagation within the fused silica substrate. The optical system includes a vertical cavity surface-emitting laser (VCSEL) array, two high performance microlenses and a commercial photodetector. The microlenses are multilevel diffractive optics patterned by electron beam lithography and etched by reactive ion etching in fused silica. Two generations of optical subsystems are described. The first generation design is integrated directly onto the capillary channel-containing substrate with a 6 mm separation between the VCSEL and photodetector. The second generation design separates the optical system onto its own module and the source to detector length is further compressed to 3.5 mm. The systems are designed for indirect fluorescence detection using infrared dyes. The first generation design has been tested with a 750 nm VCSEL exciting a 10(-4) M solution of CY-7 dye. The observed signal-to-noise ratio of better than 100:1 demonstrates that the background signal from scattered pump light is low despite the compact size of the optical system and meets the system sensitivity requirements. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Warren, ME (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 20 TC 8 Z9 8 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 0-8194-3475-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3878 BP 185 EP 192 DI 10.1117/12.361260 PG 8 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BP12U UT WOS:000084201000020 ER PT S AU Plummer, DW AF Plummer, DW BE Motomedi, ME Goering, R TI MOEMS applications at Sandia National Laboratories SO MINIATURIZED SYSTEMS WITH MICRO-OPTICS AND MEMS SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Miniaturized Systems with Micro-Optics and MEMS CY SEP 20-22, 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 MEMS; microsystems; optical integration ID PERFORMANCE AB MicroOptoElecroMechanical (MOEM) devices include both the application of micromechanics to control micro-optical systems and the application of micro-optical systems to provide monitoring and feedback for micromechanical systems. This paper presents microsystem applications at Sandia National Laboratories that require the integration of micromechanics with transmissive and reflective micro-optical systems to achieve specific functions. The goal of the presentation is to provide "system pull" by discussing the enhanced functionality of MOEMS. In particular, this paper describes MOEM systems based on polycrystalline silicon sacrificial Surface MicroMachining (SMM) devices. In one example, an environmental sensor, a Gallium Arsenide (GaAs) Photonic Integrated Circuit (PIC) is assembled with an SMM device and an Application-Specific Integrated Circuit (ASIC) to achieve a specific function. The PIC is used to monitor the SMM device. The PIC output is processed by the ASIC to generate a specific signal. The second system illustrates the micromechanical control of an optical beam. This system consists of an SMM shutter device that has been post-processed using High Aspect Ratio Silicon Etching (HARSE) to accept a Vertical Cavity Surface Emitting Laser (VCSEL). Another system in the early stages of development is an SMM mechanical timer, which illustrates the need for the development of compact, multi-channel micro-optical monitoring technologies. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM dwplumm@sandia.gov NR 14 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 0-8194-3475-2 J9 PROC SPIE PY 1999 VL 3878 BP 230 EP 237 DI 10.1117/12.361265 PG 8 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BP12U UT WOS:000084201000025 ER PT S AU Holswade, SC Dickey, FM Sullivan, CT Polosky, MA Shagam, RN AF Holswade, SC Dickey, FM Sullivan, CT Polosky, MA Shagam, RN BE Motomedi, ME Goering, R TI Optical readout of micro-accelerometer code features SO MINIATURIZED SYSTEMS WITH MICRO-OPTICS AND MEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Miniaturized Systems with Micro-Optics and MEMS CY SEP 20-22, 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 MEMS; accelerometer; optical readout AB Micromachine accelerometers offer a way to enable critical functions only when a system encounters a particular acceleration environment. This paper describes the optical readout of a surface micromachine accelerometer containing a unique 24-bit code. The readout uses waveguide-based optics, which are implemented as a photonic integrated circuit (PIC). The PIC is flip-chip bonded over the micromachine, for a compact package. The shuffle moves 500 mu m during readout, and each code element is 17 mu m wide. The particular readout scheme makes use of backscattered radiation from etched features in the accelerometer shuttle. The features are etched to create corner reflectors that return radiation back toward the source for a "one" bit. For a "zero" bit, the shuttle is not etched, and the radiation scatters forward, away from the detector. This arrangement provides a large signal difference between a "one" and "zero" signal, since the "zero" signal returns virtually no signal to the detector. It is thus superior to schemes that interrogate the code vertically, which have a limited contrast between a "one" and a "zero". Experimental results are presented for mock shuttle features etched into a silicon substrate. To simulate the shuffle moving under a fixed PIC, a commercially available waveguide source was scanned over the mock code. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Holswade, SC (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 16 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 0-8194-3475-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3878 BP 245 EP 252 DI 10.1117/12.361267 PG 8 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BP12U UT WOS:000084201000027 ER PT S AU Evans, BM Schonberger, DW Datskos, PG AF Evans, BM Schonberger, DW Datskos, PG BE Motomedi, ME Goering, R TI Finite element modeling of micromachined MEMS photon devices SO MINIATURIZED SYSTEMS WITH MICRO-OPTICS AND MEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Miniaturized Systems with Micro-Optics and MEMS CY SEP 20-22, 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 quantum MEMS; photoinduced stress; photostriction; quantum detector; finite element analysis ID ELECTRONIC STRAIN; MICROCANTILEVERS; SILICON AB The technology of microelectronics that has evolved over the past half century is one of great power and sophistication and can now be extended to many applications (MEMS and MOEMS) other than electronics. An interesting application of MEMS quantum devices is the detection of electromagnetic radiation. The operation principle of MEMS quantum devices is based on the photoinduced stress in semiconductors, and the photon detection results from the measurement of the photoinduced bending. These devices can be described as micromechanical photon detectors. In this work, we have developed a technique for simulating electronic stresses using finite element analysis. We have used our technique to model the response of micromechanical photon devices to external stimuli and compared these results with experimental data. Material properties, geometry, and bimaterial design play an important role in the performance of micromechanical photon detectors. We have modeled these effects using finite element analysis and included the effects of bimaterial thickness coating, effective length of the device, width, and thickness. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Evans, BM (reprint author), Oak Ridge Natl Lab, MS 8039, Oak Ridge, TN 37830 USA. NR 27 TC 1 Z9 1 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 0-8194-3475-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3878 BP 253 EP 260 DI 10.1117/12.361268 PG 8 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BP12U UT WOS:000084201000028 ER PT S AU Shagam, RN Dickey, FM Holswade, SC AF Shagam, RN Dickey, FM Holswade, SC BE Motomedi, ME Goering, R TI Design and analysis of a micro-optical position readout for acceleration sensing SO MINIATURIZED SYSTEMS WITH MICRO-OPTICS AND MEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Miniaturized Systems with Micro-Optics and MEMS CY SEP 20-22, 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 raytrace; micromachines; photonic integrated circuit; accelerometers AB Sandia National Laboratories is developing a MEMS-based trajectory safety subsystem, which allows enablement of critical functions only after a particular acceleration environment has been achieved. The device, known as an Environmental Sensing Device (ESD), consists of a suspended moving shuttle that translates a given distance when exposed to an appropriate acceleration environment. The shuttle contains an embedded code, consisting of grating structures, that is illuminated and optically read using a semiconductor laser and detector integrated together in a GaAs-based Photonic Integrated Circuit (PIC) flip-chip bonded to the assembly. This paper will describe the optical design and peformance analysis of the embedded code features in the shuttle. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Shagam, RN (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 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 0-8194-3475-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3878 BP 319 EP 327 DI 10.1117/12.361275 PG 9 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BP12U UT WOS:000084201000035 ER PT S AU Campisi, J AF Campisi, J BE Bohr, VA Clark, BFC Stevnsner, T TI Cellular senescence, aging and cancer SO MOLECULAR BIOLOGY OF AGING SE ALFRED BENZON SYMPOSIUM SERIES LA English DT Proceedings Paper CT 44th Alfred Benzon Symposium on Molecular Biology of Aging CY JUN 14-18, 1998 CL ROYAL DANISH ACAD SCI & LETTERS, COPENHAGEN, DENMARK SP Royal Danish Acad Sci & Letters HO ROYAL DANISH ACAD SCI & LETTERS ID HUMAN-DIPLOID FIBROBLASTS; REPLICATIVE SENESCENCE; LIFE-SPAN; CELLS; EXPRESSION; EXTENSION; GENES; MICE C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Cell & Mol Biol, Berkeley, CA 94720 USA. RP Campisi, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Cell & Mol Biol, Mailstop 70A-1118,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 33 TC 4 Z9 4 U1 0 U2 0 PU MUNKSGAARD PI COPENHAGEN K PA 35 NORRE SOGADE POSTBOX 2148, DK-1016 COPENHAGEN K, DENMARK SN 0105-3639 BN 87-16-12176-7 J9 ALFRED BENZON SYMP S PY 1999 VL 44 BP 112 EP 118 PG 7 WC Biochemistry & Molecular Biology; Geriatrics & Gerontology SC Biochemistry & Molecular Biology; Geriatrics & Gerontology GA BP88U UT WOS:000086496400008 ER PT J AU Baker, RJ Makova, KD Chesser, RK AF Baker, RJ Makova, KD Chesser, RK TI Microsatellites indicate a high frequency of multiple paternity in Apodemus (Rodentia) SO MOLECULAR ECOLOGY LA English DT Article DE Apodemus; microsatellites; multiple paternity; Murinae ID POPULATIONS; SIZES AB Microsatellites were employed to estimate frequency of multiple paternity litters of two species (genus Apodemus): striped field mouse (A. agrarius), and wood mouse (A. sylvaicus). Ten pregnant females of A. agrarius and six of A. sylvatictus were collected from natural populations in the northern Ukraine and analysed with 11 and nine microsatellite loci, respectively. Multiple paternity was indicated in eight of 10 litters in A. agrarius and in three of six litters in A. sylvaticus. Multiple paternity was documented at several loci (ranging from two to 10). In two cases (A. agrarius), three males were estimated to have fathered the litter. C1 Texas Tech Univ, Dept Biol Sci, Lubbock, TX 79409 USA. Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Makova, KD (reprint author), Texas Tech Univ, Dept Biol Sci, Lubbock, TX 79409 USA. EM kateryna@ttu.edu NR 14 TC 57 Z9 59 U1 0 U2 13 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0962-1083 J9 MOL ECOL JI Mol. Ecol. PD JAN PY 1999 VL 8 IS 1 BP 107 EP 111 DI 10.1046/j.1365-294X.1999.00541.x PG 5 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 161BX UT WOS:000078269200011 PM 12187947 ER PT S AU Hasebe, N Shibamura, E Atarashiya, T Doke, T d'Uston, C Grande, M Kashiwagi, T Kikuchi, J Kobayashi, M Kubo, K Mitani, S Mori, K Narasaki, K Nomi, K Takashima, T Tanibata, R Reedy, RC AF Hasebe, N Shibamura, E Atarashiya, T Doke, T d'Uston, C Grande, M Kashiwagi, T Kikuchi, J Kobayashi, M Kubo, K Mitani, S Mori, K Narasaki, K Nomi, K Takashima, T Tanibata, R Reedy, RC BE Ip, WH Foing, BH Masson, PL TI Gamma-Ray Spectrometer for Japanese lunar polar orbiter SO MOON AND MARS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT Symposia B0 3 and B0 4 of COSPAR Scientific Commission B held at the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP NASA, Int Astronom Union, Inst Space & Astronaut Sci, Int Union Geodes & Geophys, Ctr Natl Etudes Spatiales, Comm Space Res AB We review the current status of the development of Gamma-Ray Spectrometer (GRS) for the Lunar mission SELENE. The GRS instrument will measure gamma-rays in the energy range from 100 keV to 9 MeV. The instrument is a high-purity Ge detector surrounded by EGO and plastic scintillators which are operated as an anticoincidence shield, and is cooled by a Stirling cycle cryocooler. The primary objective is to provide global maps of the lunar composition. Measurements are anticipated for Fe, Ti, U, Th, K, Si, Mg, Al, O, Ca and Na over the entire lunar surface. The abundance of water ice in the permanently shaded craters at both the lunar poles will be measured with this instrument. (C) 1999 COSPAR. Published by Elsevier Science Ltd. C1 Waseda Univ, Adv Res Ctr Sci & Engn, Shinju Ku, Tokyo, Japan. Saitama Coll Hlth, Okubo, Saitama, Japan. Ehime Univ, Dept Comp Sci, Matsuyama, Ehime, Japan. CESR, UPS, CNRS, Colonel Roche, France. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Kanagawa Univ, Fac Engn, Kanagawa, Japan. Clear Pulse Ltd, Ohta Ku, Tokyo, Japan. Sumitomo Heavy Ind Ltd, Niihama Works, Niihama, Ehime, Japan. Los Alamos Sci Lab, Los Alamos, NM 87545 USA. RP Hasebe, N (reprint author), Waseda Univ, Adv Res Ctr Sci & Engn, Shinju Ku, Tokyo, Japan. RI Grande, Manuel/C-2242-2013; OI Grande, Manuel/0000-0002-2233-2618; Reedy, Robert/0000-0002-2189-1303 NR 6 TC 11 Z9 12 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 1999 VL 23 IS 11 BP 1837 EP 1840 DI 10.1016/S0273-1177(99)00541-4 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP01A UT WOS:000083814100009 ER PT B AU De Breuck, C van Breugel, W Rottgering, H Miley, G Stanford, A AF De Breuck, C van Breugel, W Rottgering, H Miley, G Stanford, A BE Rottgering, HJA Best, PN Lehnert, MD TI Searches for high redshift radio galaxies SO MOST DISTANT RADIO GALAXIES LA English DT Proceedings Paper CT Colloquium on the Most Distant Radio Galaxies CY OCT 15-17, 1997 CL AMSTERDAM, NETHERLANDS SP Royal Netherlannds Academy of Arts & Sci ID IDENTIFICATIONS; SAMPLE; SKY AB We have started a search for High Redshift Galaxies (HzRGs) in an area covering 7 sr by selecting a sample of Ultra Steep Spectrum (USS) sources with a low flux density cut-off S1400 > 10 mJy and a steep spectral index alpha < -1.3 (S proportional to nu(alpha)) using the WENSS, NVSS and TEXAS radio surveys. Preliminary results for 25 sources show that we are brighter radio sources and less steep radio spectra (a < -1.0). The redshift distribution is consistent with an extension of the s - alpha relation to alpha < 1.3, but a large fraction of our sample (40%) consists of objects which are too faint to observe with 3-4m class telescopes. The first results from our Keck K-band imaging and spectroscopy program indicate that these faint objects are our best candidates to detect IIzRGs at s > 3.5. Our search is aimed at significantly increasing the number of very high redshift radio galaxies for further detailed studies of the formation and evolution of massive galaxies and their environment. 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 15 TC 0 Z9 0 U1 0 U2 0 PU KONINKLIJKE AKAD WETENSCHAPPENVERHANDELINGEN, AFD NAT PI AMSTERDAM PA KLOVENIERSBURGWAL 29, P O BOX 19121, 1000 GC AMSTERDAM, NETHERLANDS BN 90-6984-238-6 PY 1999 BP 477 EP 484 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ84X UT WOS:000089817700040 ER PT J AU Bartram, ME Creighton, JR AF Bartram, ME Creighton, JR TI GaN CVD reactions: Hydrogen and ammonia decomposition and the desorption of gallium SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article DE nitrides; GaN; GaN(0001); MOCVD; hydrogen; ammonia; Ga surfaces ID SURFACES AB Isotopic labeling experiments have revealed correlations between hydrogen reactions, Ga desorption, and ammonia decomposition in GaN CVD. Low energy electron diffraction (LEED) and temperature programmed desorption (TPD) were used to demonstrate that hydrogen atoms are available on the surface for reaction after exposing GaN(0001) to deuterium at elevated temperatures. Hydrogen reactions also lowered the temperature for Ga desorption significantly. Ammonia did not decompose on the surface before hydrogen exposure. However, after hydrogen reactions altered the surface, (NH3)-H-15 did undergo both reversible and irreversible decomposition. This also resulted in the desorption of N-2 of mixed isotopes below the onset of GaN sublimation. This suggests that the driving force of the high nitrogen-nitrogen bond strength (226 kcal/mol) can lead to the removal of nitrogen from the substrate when the surface is nitrogen rich. Overall, these findings indicate that hydrogen can influence GaN CVD significantly, being a common factor in the reactivity of the surface, the desorption of Ga, and the decomposition of ammonia. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Bartram, ME (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 3 Z9 3 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G3.68 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200057 ER PT J AU Cao, XA Ren, F Lothian, JR Pearton, SJ Abernathy, CR Zolper, JC Cole, MW Zeitouny, A Eizenberg, M Shul, RJ AF Cao, XA Ren, F Lothian, JR Pearton, SJ Abernathy, CR Zolper, JC Cole, MW Zeitouny, A Eizenberg, M Shul, RJ TI Behavior of W and WSix contact metallization on n- and p- type GaN SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID OHMIC CONTACTS; ELECTRICAL-PROPERTIES; THERMAL-STABILITY; GALLIUM NITRIDE; TEMPERATURE; GROWTH; FILMS AB Sputter-deposited W-based contacts on p-GaN (N(A)similar to 10(18) cm(-3)) display non-ohmic behavior independent of annealing temperature when measured at 25 degrees C. The transition to ohmic behavior occurs above similar to 250 degrees C as more of the accepters become ionized. The optimum annealing temperature is similar to 700 degrees C under these conditions. These contacts are much more thermally stable than the conventional Ni/Au metallization, which shows a severely degraded morphology even at 700 degrees C. W-based contacts may be ohmic as-deposited on very heavily doped n-GaN, and the specific contact resistance improves with annealing up to similar to 900 degrees C. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Multiplex Inc, S Plainfield, NJ 07080 USA. Off Naval Res, Arlington, VA 22217 USA. USA, Res Lab, WMRD, Aberdeen Proving Ground, MD 21105 USA. Technion Israel Inst Technol, Dept Mat Engn, IL-32000 Haifa, Israel. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Cao, XA (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 24 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G6.39 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200108 ER PT J AU Cho, H Hahn, YB Hays, DC Jung, KB Donovan, SM Abernathy, CR Pearton, SJ Shul, RJ AF Cho, H Hahn, YB Hays, DC Jung, KB Donovan, SM Abernathy, CR Pearton, SJ Shul, RJ TI Inductively coupled plasma etching of III-nitrides in Cl-2/Xe, Cl-2/Ar and Cl-2/He SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID FIELD-EFFECT TRANSISTORS; MOLECULAR-BEAM EPITAXY; OHMIC CONTACTS; GAN; INN; PERFORMANCE; GROWTH AB The role of additive noble gases He, Ar and Xe to Cl-2-based Inductively Coupled Plasmas for etching of GaN, AlN and InN were examined. The etch rates were a strong function of chlorine concentration, rf chuck power and ICP source power. The highest etch rates for InN were obtained with Cl-2/Xe, while the highest rates for AIN and GaN were obtained with Cl-2/He. Efficient breaking of the m-nitrogen bond is crucial for attaining high etch rates. The InN etching was dominated by physical sputtering, in contrast to GaN and AlN. In the latter cases, the etch rates were limited by initial breaking of the III-nitrogen bond. Maximum selectivities of similar to 80 for InN to GaN and InN to AlN were obtained. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Cho, H (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 26 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G6.56 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200121 ER PT J AU Coltrin, ME Willan, CC Bartram, ME Han, J Missert, N Crawford, MH Baca, AG AF Coltrin, ME Willan, CC Bartram, ME Han, J Missert, N Crawford, MH Baca, AG TI Transport, growth mechanisms, and material quality in GaN epitaxial lateral overgrowth SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID VAPOR-PHASE EPITAXY; CATHODOLUMINESCENCE; DIODES AB Growth kinetics, mechanisms, and material quality in GaN epitaxial lateral over-growth (ELO) were examined using a single mask of systematically varied patterns. A 2-D gas phase reaction/diffusion model describes how transport of the Ga precursor to the growth surface enhances the lateral rate in the early stages of growth. In agreement with SEM studies of truncated growth runs, the model also predicts the dramatic decrease in the lateral rate that occurs as GaN over-growth reduces the exposed area of the mask. At the point of convergence, a step-flow coalescence mechanism is observed to fill in the area between lateral growth-fronts. This alternative growth mode in which a secondary growth of GaN is nucleated along a single convergence line, may be responsible for producing smooth films observed to have uniform cathodoluminescence (CL) when using 1 mu m nucleation zones. Although emission is comprised of both UV (similar to 365nm) and yellow (similar to 550nm) components, the spectra suggest these films have reduced concentrations of threading dislocations normally associated with non-radiative recombination centers and defects known to accompany growth-front convergence lines. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Coltrin, ME (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 3 Z9 3 U1 1 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G6.9 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200093 ER PT J AU Follstaedt, DM Han, J Provencio, P Fleming, JG AF Follstaedt, DM Han, J Provencio, P Fleming, JG TI Microstructure of GaN grown on (111) Si by MOCVD SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID SILICON; FILMS AB Gallium nitride was grown on (111) Si by MOCVD by depositing an AIN buffer at 1080 degrees C followed by GaN at 1060 degrees C. The 2.2 mu m layer cracked along {1-100} planes upon cooling to room temperature, but remained adherent. Fire were nonetheless able to examine the material between cracks with TEM. The character and arrangement of dislocations are much like those of GaN grown on Al2O3: similar to 2/3 pure edge and similar to 1/3 mixed ledge + screw), arranged in boundaries around domains of GaN that are slightly misoriented with respect to neighboring material. The 30 nm AIN buffer is continuous, indicating that AIN wets the Si, in contrast to GaN on Al2O3. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Follstaedt, DM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 10 TC 7 Z9 7 U1 0 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G3.72 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200061 ER PT J AU Han, J Crawford, MH Shul, RJ Hearne, SJ Chason, E Figiel, JJ Banas, M AF Han, J Crawford, MH Shul, RJ Hearne, SJ Chason, E Figiel, JJ Banas, M TI Monitoring and controlling of strain during MOCVD of AlGaN for UV optoelectronics SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID EPITAXIAL LAYERS; GAN; EVOLUTION; STRESS; SAPPHIRE; FILMS AB The grown-in tensile strain, due to a lattice mismatch between AlGaN and GaN, is responsible for the observed cracking that seriously limits the feasibility of nitride-based ultraviolet (UV) emitters, We report in-situ monitoring of strain/stress during MOCVD of AlGaN based on a wafer-curvature measurement technique. The strain/stress measurement confirms the presence of tensile strain during growth of AlGaN pseudomorphically on a thick GaN layer. Further growth leads to the onset of stress relief through crack generation. We find that the growth of AlGaN directly on low-temperature (LT) GaN or AlN buffer layers results in a reduced and possibly controllable strain. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Han, J (reprint author), Sandia Natl Labs, MS-0601,POB 5800, Albuquerque, NM 87185 USA. NR 19 TC 11 Z9 11 U1 1 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G7.7 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200129 ER PT J AU Kim, HS Lin, JY Jiang, HX Chow, WW Botchkarev, A Morkoc, H AF Kim, HS Lin, JY Jiang, HX Chow, WW Botchkarev, A Morkoc, H TI Piezoelectric effects in GaN/AlGaN multiple quantum wells probed by picosecond time-resolved photoluminescence SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID MOLECULAR-BEAM EPITAXY; OPTICAL-TRANSITIONS; GAN; TRANSISTORS; FIELDS AB Piezoelectric effects in GaN/AlGaN multiple quantum wells (MQWs) have been directly probed by picosecond time-resolved photoluminescence (PL) spectroscopy. The time-resolved PL spectra of the 40 Angstrom well MQWs reveal that the PL transition peak position is in fact blueshifted at early delay times due to the collective effects of quantum confinement of carriers, piezoelectric field, and Coulomb screening. However, the spectral peak position shifts toward lower energies as the delay rime increases and becomes redshifted at longer delay times. By comparing experimental and calculation results, we have obtained a low limit of the piezoelectric field strength to be about 560 kV/cm in the 40 Angstrom well. GaN/Al0.15Ga0.85N MQWs. C1 Kansas State Univ, Dept Phys, Manhattan, KS 66506 USA. Sandia Natl Labs, Albuquerque, NM USA. Virginia Commonwealth Univ, Dept Elect Engn & Phys, Richmond, VA 23284 USA. RP Kim, HS (reprint author), Kansas State Univ, Dept Phys, Cardwell Hall, Manhattan, KS 66506 USA. RI Lin, Jingyu/A-7276-2011; Jiang, Hongxing/F-3635-2011 OI Lin, Jingyu/0000-0003-1705-2635; Jiang, Hongxing/0000-0001-9892-4292 NR 16 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G3.3 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200017 ER PT J AU Myers, SM Headley, TJ Hills, CR Han, J Petersen, GA Seager, CH Wampler, WR AF Myers, SM Headley, TJ Hills, CR Han, J Petersen, GA Seager, CH Wampler, WR TI The behavior of ion-implanted hydrogen in gallium nitride SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID GAN; POLARITY; CRYSTALS AB Hydrogen was ion-implanted into wurtzite-phase GaN, and its transport, bound states, and microstructural effects during annealing up to 980 degrees C were investigated by nuclear-reaction profiling, ion-channeling analysis, transmission electron microscopy, and infrared (IR) vibrational spectroscopy. At implanted concentrations boolean OR 1 at.%, faceted H-2 bubbles formed, enabling identification of energetically preferred surfaces, examination of passivating N-H states on these surfaces, and determination of the diffusivity-solubility product of the H. Additionally, the formation and evolution of point and extended defects arising from implantation and bubble formation were characterized. At implanted H concentrations boolean AND 0.1 at.%, bubble formation was not observed, and ion-channeling analysis indicated a defect-related H site located within the [0001] channel. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Myers, SM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G5.8 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200083 ER PT J AU Qiao, D Yu, LS Lau, SS Sullivan, GJ Ruvimov, S Liliental-Weber, Z AF Qiao, D Yu, LS Lau, SS Sullivan, GJ Ruvimov, S Liliental-Weber, Z TI Contact issues of GaN technology SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID SI-IMPLANTATION; OHMIC CONTACTS; N-ALGAN AB In this paper, we discuss the issue of fabricating reliable and reproducible ohmic contacts on AlGaN HFET structures. During the course of our investigation of fabricating contacts to HFETs, we found that the contact properties could vary significantly from one sample to another, even though they were nominally the same. This problem was prominently manifested in the ohmic contact behavior. The origin of this problem was traced back to the variation of the HFET structure during growth. In this paper, we report an attempt to fabricate reproducible ohmic contacts of these structures. C1 Univ Calif San Diego, Dept Elect & Comp Engn, La Jolla, CA 92093 USA. Rockwell Int Corp, Ctr Sci, Thousand Oaks, CA 91360 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Qiao, D (reprint author), Univ Calif San Diego, Dept Elect & Comp Engn, La Jolla, CA 92093 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 9 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G1.5 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200006 ER PT J AU Shan, W Ager, JW Walukiewicz, W Haller, EE McCluskey, MD Johnson, NM Bour, DP AF Shan, W Ager, JW Walukiewicz, W Haller, EE McCluskey, MD Johnson, NM Bour, DP TI Pressure dependence of optical transitions SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID QUANTUM-WELLS; INXGA1-XN AB The effect of hydrostatic pressure on optical transitions in InGaN/GaN multiple quantum wells (MQWs) has been studied. Photoluminescence (PL) and photomodulated transmission (PT) measurements were performed under applied pressure to examine the pressure dependence of optical transitions associated with confined states in MQWs. The PL emission from the MQWs was found to shift linearly to higher energy with applied pressure but exhibit a significantly weaker pressure dependence compared to epilayer samples with similar bandgap energies. Similar pressure coefficients obtained by PT measurements rule out the possibility of PL resulting from deep localized states. We show that the difference in the compressibility of InGaN and of GaN induces a tensile strain in the compressively strained InGaN well layers that partially compensates the applied hydrostatic pressure. This mechanical effect is the primary factor for the smaller pressure dependence of the optical transitions in the InGaN/GaN MQWs. At pressure above 100 kbar, the PL signal in MQWs samples is quenched, indicating that the carriers involved in the radiative recombination processes in the well layers originate primarily from the adjacent GaN layers. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Washington State Univ, Dept Phys, Pullman, WA 99164 USA. Xerox Corp, Palo Alto Res Ctr, Palo Alto, CA 94304 USA. RP Shan, W (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G3.15 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200027 ER PT J AU Shul, RJ Zhang, L Willison, CG Han, J Pearton, SJ Hong, J Abernathy, CR Lester, LF AF Shul, RJ Zhang, L Willison, CG Han, J Pearton, SJ Hong, J Abernathy, CR Lester, LF TI Group-III nitride etch selectivity in BCl3/Cl-2 ICP plasmas SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID INDUCTIVELY-COUPLED PLASMA; GALLIUM NITRIDE; V NITRIDES; GAN; INP; CL-2/AR; IBR/AR; ALN AB Patterning the group-III nitrides has been challenging due to their strong bond energies and relatively inert chemical nature as compared to other compound semiconductors. Plasma etch processes have been used almost exclusively to pattern these films. The use of high-density plasma etch systems, including inductively coupled plasmas (ICP), has resulted in relatively high etch rates (often greater than 1.0 mu m/min) with anisotropic profiles and smooth etch morphologies. However, the etch mechanism is often dominated by high ion bombardment energies which can minimize etch selectivity. The use of an ICP-generated BCl3/Cl-2 plasma has yielded a highly versatile GaN etch process with rates ranging from 100 to 8000 Angstrom/min making this plasma chemistry a prime candidate for optimization of etch selectivity. In this study, we will report ICP etch rates and selectivities for GaN, AlN, and InN as a function of BCl3/Cl-2 flow ratios, cathode rf-power, and ICP-source power. GaN:InN and GaN:AlN etch selectivities were typically less than 7:1 and showed the strongest dependence on flow ratio. This trend may be attributed to faster GaN etch rates observed at higher concentrations of atomic Cl which was monitored using optical emission spectroscopy (OES). C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Univ New Mexico, Albuquerque, NM 87131 USA. RP Shul, RJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 25 TC 1 Z9 1 U1 0 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G8.1 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200131 ER PT J AU Wei, CH Xie, ZY Edgar, JH Zeng, KC Lin, JY Jiang, HX Ignatiev, C Chaudhuri, J Braski, DN AF Wei, CH Xie, ZY Edgar, JH Zeng, KC Lin, JY Jiang, HX Ignatiev, C Chaudhuri, J Braski, DN TI Growth and characterization of BxGa1-xN on 6H-SiC (0001) by MOVPE SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID BORON-NITRIDE AB Boron was incorporated into GaN in order to determine its limits of solubility, its ability of reducing the lattice constant mismatch with 6H-SiC, as well as its effects on the structural and optical properties of GaN epilayers. BxGa1-xN films were deposited on 6H-SiC (0001) substrates at 950 degrees C by low pressure MOVPE using diborane, trimethylgallium, and ammonia as precursors. A single phase alloy with x=0.015 was successfully produced at a gas reactant B/Ga ratio of 0.005. Phase separation into pure GaN and BxGa1-xN alloy with x=0.30 was deposited for a B/Ga reactant ratio of 0.01. This is the highest B fraction of the wurtzite structure alloy ever reported. For B/Ga ratio greater than or equal to 0.02, no BxGa1-xN was formed, and the solid solution contained two phases: wurtzite GaN and BN based on the results of Auger and x-ray diffraction. The band edge emission of BxGa1-xN varied from 3.451 eV for x=0 with FWHM of 39.2 meV to 3.465 eV for x=0.015 with FWHM of 35.1 meV. The narrower FWHM indicated that the quality of GaN epilayer was improved with small amount of boron incorporation. C1 Kansas State Univ, Dept Chem Engn, Manhattan, KS 66506 USA. Kansas State Univ, Dept Phys, Manhattan, KS 66506 USA. Wichita State Univ, Dept Mech Engn, Wichita, KS 67260 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Wei, CH (reprint author), Kansas State Univ, Dept Chem Engn, Durland Hall, Manhattan, KS 66506 USA. RI Lin, Jingyu/A-7276-2011; Jiang, Hongxing/F-3635-2011; Chaudhuri, Jharna/E-8863-2013 OI Lin, Jingyu/0000-0003-1705-2635; Jiang, Hongxing/0000-0001-9892-4292; NR 6 TC 0 Z9 0 U1 0 U2 6 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 BP art. no. EP G3.79 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200067 ER PT J AU Cao, XA Pearton, SJ Singh, RK Abernathy, CR Han, J Shul, RJ Rieger, DJ Zolper, JC Wilson, RG Fu, M Sekhar, JA Guo, HJ Pennycook, SJ AF Cao, XA Pearton, SJ Singh, RK Abernathy, CR Han, J Shul, RJ Rieger, DJ Zolper, JC Wilson, RG Fu, M Sekhar, JA Guo, HJ Pennycook, SJ TI Rapid thermal processing of implanted GaN up to 1500 degrees C SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID ION-IMPLANTATION; SI-IMPLANTATION; TEMPERATURE; DEFECTS AB GaN implanted with donor(Si, S, Se, Te) or acceptor (Be, Mg, C) species was annealed at 900-1500 degrees C using AlN encapsulation. No redistribution was measured by SIMS for any of the dopants and effective diffusion coefficients are less than or equal to 2x10(-13) cm(2) . s(-1) at 1400 degrees C, except Be, which displays damage-enhanced diffusion at 900 degrees C and is immobile once the point defect concentration is removed. Activation efficiency of similar to 90% is obtained for Si at 1400 degrees C. TEM of the implanted material shows a strong reduction in lattice disorder at 1400-1500 degrees C compared to previous results at 1100 degrees C. There is minimal interaction of the sputtered AlN with GaN under our conditions, and it is readily removed selectively with KOH. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Off Naval Res, Arlington, VA 22217 USA. Micropyret Heaters Int Inc, Cincinnati, OH 45215 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Cao, XA (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 23 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 AR G6.33 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200106 ER PT J AU Cho, H Donovan, SM Abernathy, CR Pearton, SJ Ren, F Han, J Shul, RJ AF Cho, H Donovan, SM Abernathy, CR Pearton, SJ Ren, F Han, J Shul, RJ TI Photoelectrochemical etching of InxGa1-xN SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID III-V-SEMICONDUCTORS; N-TYPE GAN; GALLIUM NITRIDE; WET; ALN AB A comparison of KOH, NaOH and AZ400K solutions for UV photo-assisted etching of undoped and n(+) GaN is discussed. The etching is diffusion-limited (E-a < 6kCal.mol(-1)) under all conditions and is significantly faster with bias applied to the sample during light exposure. No etching of InN was observed, due to the very high n-type background doping (> 10(20)cm(-3)) in the material. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Cho, H (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 24 TC 1 Z9 1 U1 0 U2 5 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 AR G6.40 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200109 ER PT J AU Jiang, W Weber, WJ Thevuthasan, S Exarhos, GJ Bozlee, BJ AF Jiang, W Weber, WJ Thevuthasan, S Exarhos, GJ Bozlee, BJ TI Effect of oxygen ion implantation in gallium nitride SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID GAN; CA; ACCUMULATION; DAMAGE AB Epitaxial single crystal GaN films (2.0 mu m thick) were implanted 60 degrees off the <0001> surface normal with 600 keV O+ ions at 190 or 210 K over a range of ion fluences from 4.8x10(17) to 5.0x10(20) ions/m(2). The implantation damage, as determined by in-situ Rutherford Backscattering Spectrometry in a <0001> channeling geometry (RBS/C), ranged from dilute defects up to the formation of a disorder saturation state that was not fully amorphous. The relative disorder on the Ga sublattice exhibited a sigmoidal dependence on ion fluence. Results show that GaN crystals are extremely resistant to the ion implantation damage as compared to other ceramic materials like SiC. An asymmetric shape in the angular scan curve around the <0001> axis, which might be associated with the Ga lattice distortion in the crystal structure, was observed for the as-irradiated material to the highest ion fluence (5.0x10(20) O+/m(2)) at 210 K. Comparisons of Ga disorder depth-profiles from the experiment and SRIM97 simulations suggest that the damage peaks shift to greater depths at the low irradiation temperature (210 K). Significant recovery of these defects was not observed in the isochronal annealing steps (20-min) up to 970 K. C1 Pacific NW Lab, Richland, WA 99352 USA. Univ Great Falls, Great Falls, MT 59405 USA. RP Jiang, W (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. RI Weber, William/A-4177-2008 OI Weber, William/0000-0002-9017-7365 NR 16 TC 1 Z9 1 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 AR G6.15 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200098 ER PT J AU Liliental-Weber, Z Benamara, M Swider, W Washburn, J Park, J Grudowski, PA Eiting, CJ Dupuis, RD AF Liliental-Weber, Z Benamara, M Swider, W Washburn, J Park, J Grudowski, PA Eiting, CJ Dupuis, RD TI TEM study of defects in laterally overgrown GaN layers SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID EPITAXY AB Transmission electron microscopy was applied to study defects in laterally overgrown GaN layers, with initial growth on Al2O3 substrates followed by further growth over SiO2 masks. Dislocations found in the overgrown areas shaw changes in line direction. Most dislocations propagate alone c-planes. In the overgrown material planar defects (faulted loops) are present on c-planes and their presence is most probably related to segregation of excess point defects and impurities present in this material. They appear to be initiated by the fast lateral growth. Some dislocations with screw orientation become helical resulting from climb motion. Formation of voids and also a high dislocation density was observed at the boundaries where two overgrowing fronts meet. Tilt and twist components were observed for these boundaries that were different for different overgrown strips grown in the same crystallographic direction suggesting that the GaN subgrain orientations on the two sides of a SiO2 mask are responsible for the final tilt and twist value. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Texas, Microelect Res Ctr, Austin, TX 78712 USA. RP Liliental-Weber, Z (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 10 TC 2 Z9 2 U1 1 U2 7 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 AR G4.6 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200072 ER PT J AU Reboredo, FA Pantelides, ST AF Reboredo, FA Pantelides, ST TI Defect complexes and non-equilibrium processes underlying the P-type doping of GaN SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID NATIVE DEFECTS; GALLIUM NITRIDE; HYDROGEN AB It is well known that hydrogen plays a key role in p-type doping of GaN. It is believed that H passivates substitutional Me during growth by forming a Mg-s-N-H-i complex; in subsequent annealing, H is removed, resulting in p-type doping. Several open questions have remained, however, such as experimental evidence for other complexes involving Mg and H and difficulties in accounting for the relatively high-temperature anneal needed to remove H. We present first principles calculations in terms of which we show that the doping process is in fact significantly more complex. In particular, interstitial Mg plays a major role in limiting p-type doping. Overall, several substitutional/interstitial complexes form and can bind H, with vibrational frequencies that account for hitherto unidentified observed lines. We predict that these defects, which limit doping efficiency, can be eliminated by annealing in an atmosphere of H and N prior to the final anneal that removes H. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Reboredo, FA (reprint author), Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. EM pantelides@vanderbilt.edu RI Reboredo, Fernando/B-8391-2009 NR 16 TC 1 Z9 1 U1 1 U2 5 PU MATERIALS RESEARCH SOC PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 AR G5.3 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200079 ER PT J AU Sher, A van Schilfgaarde, M Berding, MA Krishnamurthy, S Chen, AB AF Sher, A van Schilfgaarde, M Berding, MA Krishnamurthy, S Chen, AB TI Computational materials science, an increasingly reliable engineering tool: Anomalous nitride band structures and device consequences SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; GALLIUM NITRIDE; ELECTRONIC-STRUCTURE; GAN; ALLOYS; PRESSURE; ZINCBLENDE; TRANSPORT; ALXGA1-XN; GAAS1-XNX AB Computational materials science has evolved in recent years into a reliable theory capable of predicting not only idealized materials and device performance properties, but also those that apply to practical engineering developments. The codes run on workstations and even now are fast enough to be useful design tools. A review will be presented of the current status of this rapidly advancing field. Examples of the accuracy of the codes are displayed by comparing the predicted atomic volumes, and cohesive and excess energies of several materials with experiment. As a further demonstration of the methods, the band structures of AIN, GaN, and InN in wurtzite and zinc blende structures will be presented. There are anomalies in the conduction and valence bands of these materials. Some consequences on light emitting and power devices made from these materials will be examined. C1 SRI Int, Menlo Pk, CA 94025 USA. Sandia Natl Labs, Livermore, CA 94551 USA. Auburn Univ, Dept Phys, Auburn, AL 36849 USA. RP Sher, A (reprint author), SRI Int, 333 Ravenswood Ave, Menlo Pk, CA 94025 USA. NR 43 TC 4 Z9 4 U1 0 U2 0 PU MATERIALS RESEARCH SOC PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 AR G5.1 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200077 ER PT J AU Wampler, WR Myers, SM AF Wampler, WR Myers, SM TI Ion channeling analysis of gallium nitride implanted with deuterium SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID GAN; HYDROGEN; CRYSTALS; DEFECTS; MG AB Ion channeling and transmission electron microscopy were used to examine the microstructure of GaN implanted with deuterium (D)) at high (>1 at. %) and low (< 0.1 at. %) D concentrations. At high concentrations, bubbles and basal-plane stacking faults were observed, Ton channeling showed the D was disordered relative to the GaN lattice, consistent with precipitation of D-2 into bubbles. At low D concentrations, bubbles and stacking faults are absent and ion channeling shows that a large fraction of the D occupies sites near the center of the c-axis channel. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wampler, WR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM wrwampl@sandia.gov NR 15 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOC PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1999 VL 4 SU 1 AR G3.73 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200062 ER PT S AU Chirayil, TG Paranthaman, M Beach, DB Morrell, JS Sun, EY Goyal, A Williams, RK Lee, DF Martin, PM Kroeger, DM Feenstra, R Verebelyi, DT Christen, DK AF Chirayil, TG Paranthaman, M Beach, DB Morrell, JS Sun, EY Goyal, A Williams, RK Lee, DF Martin, PM Kroeger, DM Feenstra, R Verebelyi, DT Christen, DK BE Hawley, ME Blank, DHA Eom, CB Schlom, DG Streiffer, SK TI Epitaxial growth of Yb2O3 buffer layers on biaxially textured-Ni (100) substrates by sol-gel process SO MULTICOMPONENT OXIDE FILMS FOR ELECTRONICS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium BB on Multicomponent Oxide Films for Electronics, at the 1999 MRS Spring Meeting CY APR 06-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Argonne Natl Lab, Los Alamos Natl Lab, Digital Instruments Inc ID CRITICAL-CURRENT DENSITY; SUPERCONDUCTING TAPES; ALUMINATE FILMS AB In order to develop an alternative buffer layer architecture using the sol-gel process to produce YBCO (YBa2CU3O7-delta) coated conductors, Yb2O3 has been chosen as the candidate material. Buffer layers of Yb2O3 were epitaxially grown on biaxially textured-Ni (100) substrates by the sol gel process for the first time. The Yb2O3 precursor solution was prepared from an alkoxide sol-gel route in 2-methoxyethanol and was deposited on textured-Ni (100) substrates by either spin coating or dip coating methods. The amorphous film was then processed at 1160 degrees C under flowing (96%)Ar/H-2(4%) gas mixture for one hour. The Yb2O3 film exhibited a strong c-axis orientation on the Ni (100) substrates. The phi and omega scans indicated good in plane and out of plane orientations. The X-ray (222) pole figure showed a cube-on-cube epitaxy. High current YBCO films were grown on the Yb2O3 sol-gel buffered-Ni substrates. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Chirayil, TG (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Paranthaman, Mariappan/N-3866-2015 OI Paranthaman, Mariappan/0000-0003-3009-8531 NR 15 TC 9 Z9 10 U1 0 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-481-5 J9 MATER RES SOC SYMP P PY 1999 VL 574 BP 51 EP 56 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BN91P UT WOS:000083461400008 ER PT S AU Wagner, AV Johnson, GW Barbee, TW AF Wagner, AV Johnson, GW Barbee, TW BE Hawley, ME Blank, DHA Eom, CB Schlom, DG Streiffer, SK TI High energy density capacitors fabricated by thin film technology SO MULTICOMPONENT OXIDE FILMS FOR ELECTRONICS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium BB on Multicomponent Oxide Films for Electronics, at the 1999 MRS Spring Meeting CY APR 06-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Argonne Natl Lab, Los Alamos Natl Lab, Digital Instruments Inc ID OXIDES AB Low energy density in conventional capacitors severely limits efforts to miniaturize power electronics and imposes design limitations on electronics in general. We have successfully applied physical vapor deposition technology to greatly increase capacitor energy density. The high dielectric breakdown strength we have achieved in alumina thin films allows high energy density tg be achieved with this moderately low dielectric constant material. The small temperature dependence of the dielectric constant, and the high reliability, high resistivity, and low dielectric loss of Al2O3, make it even more appealing. We have constructed single dielectric layer thin film capacitors and shown that they can be stacked to form multilayered structures with no loss in yield for a given capacitance. Control of film growth morphology is critical for achieving the smooth, high quality interfaces between metal and dielectric necessary for device operation at high electric fields. Most importantly, high rate deposition with extremely low particle generation is essential for achieving high energy storage at a reasonable cost. This has been achieved by reactive magnetron sputtering in which the reaction to form the dielectric oxide has been confined to the deposition surface. By this technique we have achieved a yield of over 50% for 1 cm(2) devices with an energy density of 14 J per cubic centimeter of Al2O3 dielectric material in 1.2 kV, 4 nF devices. By further reducing defect density and increasing the dielectric constant of the material, we will be able to increase capacitance and construct high energy density devices to meet the requirements of applications in power electronics. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. RP Wagner, AV (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, 7000 E Ave, Livermore, CA 94550 USA. NR 6 TC 10 Z9 10 U1 0 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-481-5 J9 MATER RES SOC SYMP P PY 1999 VL 574 BP 219 EP 224 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BN91P UT WOS:000083461400032 ER PT S AU Wereszczak, AA Breder, K Ferber, MK Bridge, RJ Riester, L Kirkland, TP AF Wereszczak, AA Breder, K Ferber, MK Bridge, RJ Riester, L Kirkland, TP BE Jean, JH Gupta, TK Nair, KM Niwa, K TI Failure probability prediction of dielectric ceramics in multilayer capacitors SO MULTILAYER ELECTRONIC CERAMIC DEVICES 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 MEASURING FRACTURE-TOUGHNESS; INDENTATION TECHNIQUES; STRENGTH AB Dielectric ceramics in multilayer capacitors are subjected to manufacturing or service thermomechanical stresses which, if severe enough, will cause mechanical failure and perhaps subsequent loss of electrical function. Strength of monolithic ceramics is probabilistic in nature; however, probabilistic design of such electronic ceramic components generally has not been used by manufacturers and end-users of these components. To illustrate how probabilistic design may be utilized for small components, the present study demonstrates the applicability of an existing probabilistic life design computer code in the prediction of failure probability of a dielectric ceramic in an arbitrary multilayer capacitor. Issues involving the generation of representative strength and fatigue data for specimens at this small scale and the ultimate failure probability prediction of dielectric ceramics in multilayer capacitors are presented. Additionally, alternative means to generate a strength distribution as input for the probabilistic life design computer codes which are under consideration by the authors are discussed. C1 Oak Ridge Natl Lab, High Temp Mat Lab, Mech Characterizat & Anal Grp, Oak Ridge, TN 37831 USA. RP Wereszczak, AA (reprint author), Oak Ridge Natl Lab, High Temp Mat Lab, Mech Characterizat & Anal Grp, Oak Ridge, TN 37831 USA. RI Wereszczak, Andrew/I-7310-2016 OI Wereszczak, Andrew/0000-0002-8344-092X NR 21 TC 2 Z9 2 U1 0 U2 4 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 1042-1122 BN 1-57498-064-5 J9 CERAM TRANS PY 1999 VL 97 BP 73 EP 83 PG 11 WC Engineering, Electrical & Electronic; Materials Science, Ceramics SC Engineering; Materials Science GA BN02U UT WOS:000080431700007 ER PT S AU Chen, N Bai, GR Foster, CM Auciello, OH Brukman, MJ Lanagan, MT AF Chen, N Bai, GR Foster, CM Auciello, OH Brukman, MJ Lanagan, MT BE Jean, JH Gupta, TK Nair, KM Niwa, K TI Low-temperature mocvd growth of oriented PbZr(x)Ti(1-x)O3 thin films on Si substrates SO MULTILAYER ELECTRONIC CERAMIC DEVICES 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 CHEMICAL-VAPOR-DEPOSITION; PBTIO3 AB Polycrystalline Pb(Zr0.6Ti0.4)O-3 (PZT) thin films, 3000-6000 Angstrom thick, have been grown by metal-organic chemical vapor deposition (MOCVD) on (111)Pt/Ti/SiO2/Si substrates at temperatures as low as 450-525 degrees C. Random and (Ill)-oriented, or occasionally (100)-oriented, PZT films can be deposited directly on (111)Pt/Ti/SiO2/Si. In addition, highly (100)-oriented films can be deposited consistently by using 150-250 Angstrom thick (100)-oriented PbTiO3 (PT) or TiO2 as a template. Films were characterized by X-ray diffraction, electron microscopy, and electrical measurements. The as-grown (100)-oriented films on (111)Pt/TiSiO2/Si substrates exhibited dielectric constants (epsilon(r)) of up to 600, remnant polarization (P-r) of 40 mu C/cm(2), coercive field of 55 kV/cm, and breakdown field of 2-6 x 10(7) V/m. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Chen, N (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 1042-1122 BN 1-57498-064-5 J9 CERAM TRANS PY 1999 VL 97 BP 367 EP 374 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Ceramics SC Engineering; Materials Science GA BN02U UT WOS:000080431700028 ER PT S AU Rasmussen, T AF Rasmussen, T BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Atomic scale simulation of cross slip and screw dislocation dipole annihilation SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID ENERGETICS; METALS; CRYSTALS AB Atomistic simulations are used to study cross slip of a single screw dislocation as well as screw dislocation dipole annihilation in Cu. A configuration space path technique is applied to determine, without presumptions about the saddle point, the minimum energy path of transition for cross slip. The cross slip process is that proposed by Friedel and Escaig, and the energy of the in-plane constriction initiating cross slip is determined. A minimum stable dipole height much smaller than previously inferred from experimental studies is found. Relaxed screw dislocation dipoles adopt a skew configuration due to the anisotropy of Cu. The path technique is applied to investigate annihilation of stable screw dislocation dipoles, and the energy barrier for annihilation as a function of dipole height is determined for both homogeneous and heterogeneous cross slip leading to the annihilation. The results might be used as quantitative input into meso-/macro-scopical modelling approaches which rely on parameters deduced from either simulation of experiment. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Rasmussen, T (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 31 TC 2 Z9 2 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 51 EP 62 PG 12 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000005 ER PT S AU El-Azab, A AF El-Azab, A BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Image forces on 3D dislocation structures in crystals of finite volume SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID BCC SINGLE-CRYSTALS AB The present work aims at studying the image stress and image Peach-Koehler force fields for three-dimensional dislocation configurations in a single crystal of finite volume. It is shown that the image stress field is significant within the entire crystal volume, and that the image Peach-Koehler force can be of the same order of magnitude as the direct interaction force calculated from the infinite domain solution. The results demonstrate that image stress gives rise to long-range interaction forces that are important in meso-scale dynamics of dislocation structures. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP El-Azab, A (reprint author), Pacific NW Natl Lab, MSIN K5-26,902 Battelle Blvd,POB 999, Richland, WA 99352 USA. NR 7 TC 1 Z9 1 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 107 EP 112 PG 6 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000012 ER PT S AU Miodownik, MA Holm, EA Godfrey, AW Hughes, DA Lesar, R AF Miodownik, MA Holm, EA Godfrey, AW Hughes, DA Lesar, R BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Multiscale modeling of recrystallization SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID COMPUTER-SIMULATION; GROWTH AB We propose a multi length scale approach to modeling recrystallization which links a dislocation model, a cell growth model and a macroscopic model. Although this methodology and linking framework will be applied to recrystallization, it is also applicable to other types of phase transformations in bulk and layered materials. Critical processes such as the dislocation structure evolution, nucleation, the evolution of crystal orientations into a preferred texture, and grain size evolution all operate at different length scales. In this paper we focus on incorporating experimental measurements of dislocation substructures, misorientation measurements of dislocation boundaries, and dislocation simulations into a mesoscopic model of cell growth. In particular, we show how feeding information from the dislocation model into the cell growth model can create realistic initial microstructures. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Miodownik, MA (reprint author), Sandia Natl Labs, Albuquerque, NM 87185 USA. RI LeSar, Richard/G-1609-2012; OI Holm, Elizabeth/0000-0003-3064-5769 NR 10 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 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 157 EP 162 PG 6 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000018 ER PT S AU Steinzig, M Harlow, FH AF Steinzig, M Harlow, FH BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Characterization of cast metals with probability distribution functions SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID MICROSTRUCTURE FORMATION; SOLIDIFICATION AB Characterization of microstructure using a probability distribution function (PDF) provides a means for extracting useful information about material properties. In the extension of classical PDF methods developed in our research, material characteristics are evolved by propagating an initial PDF through time, using growth laws derived from consideration of heat Bow and species diffusion, constrained by the Gibbs-Thomson law. A model is described here that allows for nucleation, followed by growth of nominally spherical grains according to a stable or unstable growth law. Results are presented for the final average grain size as a function of cooling rate for various nucleation parameters. In particular we show that the model describes linear variation of final grain size with the inverse cube root of cooling rate. Within a subset of casting parameters, the stable-to-unstable manifests itself as a bimodal distribution of final grain size. Calculations with the model are described for the liquid to epsilon phase transition in a plutonium 1 weight percent gallium alloy. C1 Univ Calif Los Alamos Natl Lab, Grp T3, Los Alamos, NM 87545 USA. RP Steinzig, M (reprint author), Univ Calif Los Alamos Natl Lab, Grp T3, Los Alamos, NM 87545 USA. NR 9 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 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 185 EP 190 PG 6 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000022 ER PT S AU Stoller, RE Greenwood, LR AF Stoller, RE Greenwood, LR BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI From molecular dynamics to kinetic rate theory: A simple example of multiscale modeling SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID PRIMARY DAMAGE FORMATION; DISPLACEMENT CASCADES; METALS; IRON AB Radiation damage formation in iron has been investigated using the method of molecular dynamics simulation. The MD simulations have been used to determine primary defect production parameters for cascade energies up to 50 keV at temperatures from 100 to 900K. The energy dependence of these parameters has been used to determine appropriate neutron-energy-spectrum averaged damage production cross sections for various irradiation environments. Two applications of these effective cross sections are discussed. The first is an evaluation of neutron energy spectrum effects in commercial fission reactor pressure vessels. The second example deals with the use of these cross sections in the source term of a kinetic model used to predict void swelling and microstructural evolution. The simulation of the primary damage event by MD involves times less than 100 ps and a size scale of a few tens of nm, while the kinetic simulation encompasses several years and macroscopic sizes. This use of the MD results to develop an improved source term for rate theory modeling provides a simple example of multiscale modeling. C1 Oak Ridge Natl Lab, Mat & Ceram Div, Oak Ridge, TN 37831 USA. RP Stoller, RE (reprint author), Oak Ridge Natl Lab, Mat & Ceram Div, POB 2008, Oak Ridge, TN 37831 USA. RI Stoller, Roger/H-4454-2011; Greenwood, Lawrence/H-9539-2016 OI Greenwood, Lawrence/0000-0001-6563-0650 NR 19 TC 1 Z9 1 U1 0 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 203 EP 210 PG 8 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000025 ER PT S AU Williford, RE Weber, WJ Devanathan, R Gale, JD AF Williford, RE Weber, WJ Devanathan, R Gale, JD BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Oxygen vacancy migration in disordered Gd-2(ZrxTi1-x)(2)O-7 SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc AB Oxygen vacancy formation and migration energies in the pyrochlores Gd-2(ZrxTi1-x)(2)O-7 were computed using atomistic energy minimization methods, with particular attention to the role of cation antisite disorder. The interatomic potentials recognize oxygens in distinct crystallographic sites (polarizations) as distinct species, and permit assessment of the directional anisotropy in vacancy migration energies. Oxygen vacancy migration is determined by O-48f - O-48f transitions along the shortest edges of the TiO6 octahedra, in agreement with previous results. Oxygen vacancies migrate towards disorder to reduce local stresses. In contrast to previous work, the V-O8a and V-O8a + I-O8b Frenkel defects are favored over the V-O48f and V-O48f + I-O8b Frenkel. The transition V-O8a -> V-O48f is energetically favored for the ordered structure, and activates the three dimensional O48f- O-48f vacancy migration network by filling empty 8a sites with 48f oxygens. Local regions of order and moderate disorder must both be present for optimum oxygen conductivity. High disorder retards vacancy migration. C1 Battelle Mem Inst, Pacific NW Labs, Dept Mat, Richland, WA 99352 USA. RP Williford, RE (reprint author), Battelle Mem Inst, Pacific NW Labs, Dept Mat, POB 999, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; Gale, Julian/B-7987-2009; OI Weber, William/0000-0002-9017-7365; Gale, Julian/0000-0001-9587-9457; Devanathan, Ram/0000-0001-8125-4237 NR 16 TC 3 Z9 3 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 235 EP 240 PG 6 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000030 ER PT S AU Hjalmarson, HP Schultz, PA Bowman, DJ Fleetwood, DM AF Hjalmarson, HP Schultz, PA Bowman, DJ Fleetwood, DM BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI A unified computational approach to oxide aging processes SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID BIPOLAR JUNCTION TRANSISTORS; 111 SI-SIO2 INTERFACE; IONIZING-RADIATION; ENHANCED DAMAGE; KINETICS; CIRCUITS; DEVICES AB In this paper we describe a unified, hierarchical computational approach to aging and reliability problems caused by materials changes in the oxide layers of Si-based microelectronic devices. We apply this method to a particular low-dose-rate radiation effects problem. C1 Sandia Natl Labs, Albuquerque, NM 87111 USA. RP Hjalmarson, HP (reprint author), Sandia Natl Labs, Albuquerque, NM 87111 USA. NR 21 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 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 257 EP 262 PG 6 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000034 ER PT S AU Battaile, CC Buchheit, TE Holm, EA Wellman, GW Neilsen, MK AF Battaile, CC Buchheit, TE Holm, EA Wellman, GW Neilsen, MK BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Coupled simulations of mechanical deformation and microstructural evolution using polycrystal plasticity and Monte Carlo Potts models SO MULTISCALE MODELLING OF MATERIALS SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID COMPUTER-SIMULATION; GRAIN-GROWTH AB The microstructural evolution of heavily deformed polycrystalline Cu is simulated by coupling a constitutive model for polycrystal plasticity with the Monte Carlo Potts model for grain growth. The effects of deformation on boundary topology and grain growth kinetics are presented. Heavy deformation leads to dramatic strain-induced boundary migration and subsequent grain fragmentation. Grain growth is accelerated in heavily deformed microstructures. The implications of these results for the thermomechanical fatigue failure of eutectic solder joints are discussed. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM ccbatta@sandia.gov OI Holm, Elizabeth/0000-0003-3064-5769 NR 8 TC 4 Z9 4 U1 1 U2 2 PU MATERIALS RESEARCH SOC PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 269 EP 273 PG 5 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000036 ER PT S AU Theiss, SK Caturla, MJ de la Rubia, TD Johnson, MC Ural, A Griffin, PB AF Theiss, SK Caturla, MJ de la Rubia, TD Johnson, MC Ural, A Griffin, PB BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Linking ab initio energetics to experiment: Kinetic Monte Carlo simulation of transient enhanced diffusion of B in Si SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID PSEUDOPOTENTIAL CALCULATIONS AB We have developed a kinetic Monte Carlo (kMC) simulator that links atomic migration and binding energies determined primarily from first principles calculations to macroscopic phenomena and laboratory time scales. Input for the kMC simulation is obtained from a combination of nb initio planewave pseudopotential calculations, molecular dynamics simulations, and experimental data. The simulator is validated against an extensive series of experimental studies of the diffusion of B spikes in self-implanted Si. The implant energy, dose, and dose rate, as well as the detailed thermal history of the sample, are included. Good agreement is obtained with the experimental data for temperatures between 750 and 950 degrees C and times from 15 to 255 s. At 1050 degrees C we predict too little diffusion after 105 s compared to experiment: apparently, some mechanism which is not adequately represented by our model becomes important at this temperature. Below 1050 degrees C, the kMC simulation produces a complete description over macroscopic time scales of the atomic level diffusion and defect reaction phenomena that operate during the anneals. This simulator provides a practical method for predicting technologically interesting phenomena, such as transient enhanced diffusion of B, over a wide range of conditions, using energetics determined from first-principles approaches. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Theiss, SK (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 10 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 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 291 EP 295 PG 5 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000039 ER PT S AU Corrales, LR Van Ginhoven, RM Song, J Jonsson, H AF Corrales, LR Van Ginhoven, RM Song, J Jonsson, H BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Vacancy migration barrier energetics and pathways in silica SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID ABINITIO CALCULATIONS; FORCE-FIELDS; ALUMINOPHOSPHATES; DEFECTS AB A study of vacancy defect migration pathways and energetics in alpha-quartz is carried out using an empirical simulation methodology that is coupled with the nudged elastic band method. Results from this study indicate that the migration pathway for migration is between adjacent sites. We anticipate the results will guide modifications to empirical potentials for use in the study of point defect formation of more complex systems. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Corrales, LR (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999, Richland, WA 99352 USA. RI Jonsson, Hannes/G-2267-2013 OI Jonsson, Hannes/0000-0001-8285-5421 NR 8 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 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 317 EP 321 PG 5 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000042 ER PT S AU Zapol, P Curtiss, LA Gruen, DM AF Zapol, P Curtiss, LA Gruen, DM BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI First-principles study of pi-bonded (100) planar defects in diamond SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID EXCHANGE-ENERGY; APPROXIMATION; FILMS AB A periodic density functional study of the high-energy pi-bonded (100) stacking fault in diamond that can serve as a prototype of a twist grain boundary has been carried out. Information on formation energies, geometries and the electronic structure has been obtained. A single point electronic structure calculation of a Sigma 5 twist grain boundary based on the geometry taken from a molecular dynamics simulation has also been performed. C1 Argonne Natl Lab, Div Sci Mat, Argonne, IL 60559 USA. RP Zapol, P (reprint author), Argonne Natl Lab, Div Sci Mat, Argonne, IL 60559 USA. RI Zapol, Peter/G-1810-2012 OI Zapol, Peter/0000-0003-0570-9169 NR 8 TC 2 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 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 371 EP 376 PG 6 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000050 ER PT S AU Xie, JJ Chen, SP AF Xie, JJ Chen, SP BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Ab initio calculations of point defects in silicon SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID MOLECULAR-DYNAMICS; DIFFUSION; VACANCY; SI; MECHANISM; PRESSURE; SYSTEMS; ENERGY AB We use the ab initio plane wave pseudopotential method and the density functional theory (DFT) to study the arsenic(bs)-vacancy interactions in silicon. The detailed lattice distortions surrounding the As-vacancy defect and the energetics of As-vacancy reaction around the six-fold ring are investigated. We find that the As displaces its neighboring silicon atoms outward while the vacancy attracts its neighboring atoms inward. The binding energy and the formation energy of an As-vacancy pair are 1.21 eV and 2.37 eV, respectively. Once the vacancy and As binds together, the highest migration barrier for the whole complex is 1.19 eV, which is in good agreement with the experimental measurement of 1.07 eV. The calculated activation energy for the vacancy mediated diffusion of the neutral As in silicon is 3.56 eV. The nature of the binding between As and vacancy is explained from the lattice distortions introduced by the As-vacancy complex. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Xie, JJ (reprint author), Univ Calif Los Alamos Natl Lab, T-11,MS-B262, Los Alamos, NM 87545 USA. NR 18 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 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 389 EP 394 PG 6 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000053 ER PT S AU Voter, AF Sorensen, MR AF Voter, AF Sorensen, MR BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Accelerating atomistic simulations of defect dynamics: Hyperdynamics, parallel replica dynamics, and temperature-accelerated dynamics SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID EMBEDDED-ATOM METHOD; INFREQUENT EVENTS; MOLECULAR-DYNAMICS; ADATOM AB Obtaining a good atomistic description of diffusion dynamics in materials remains a daunting task due to the time-scale limitations of the molecular dynamics method. We discuss new methods, derived from transition state theory, for accelerating molecular dynamics simulations of these infrequent-event processes. Two of these methods (hyperdynamics and parallel replica dynamics) have been presented previously, and are briefly reviewed here. The third, temperature-accelerated dynamics (TAD), is presented in detail. In TAD, the system temperature is raised to stimulate more rapid escape out of each potential basin, but attempted transitions are filtered to allow only those that would have occurred at the normal temperature. The characteristics of the methods are compared. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Voter, AF (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 14 TC 17 Z9 17 U1 0 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 427 EP 439 PG 13 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000059 ER PT S AU Swaminarayan, S Preston, DL AF Swaminarayan, S Preston, DL BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Quantitative calculation of dislocation mobility SO MULTISCALE MODELLING OF MATERIALS SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc AB We present a new method to calculate the response of dislocations to applied stress. This new method, called the dislocation treadmill, can be used to study the effect of vacancies, interstitials, stresses, strain rate, temperature etc., on the steady state velocity of the dislocation. We demonstrate the use of the method by calculating the response of a dislocation to a constant applied shear stress. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Swaminarayan, S (reprint author), Los Alamos Natl Lab, MS G-755, Los Alamos, NM 87545 USA. NR 14 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 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 497 EP 501 PG 5 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000067 ER PT S AU Kwiat, PG Schwindt, PDD Englert, BG AF Kwiat, PG Schwindt, PDD Englert, BG BE Bonifacio, R TI What does a quantum eraser really erase? SO MYSTERIES, PUZZLES, AND PARADOXES IN QUANTUM MECHANICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Mysteries, Puzzles, and Paradoxes in Quantum Mechanics CY AUG-SEP -, 1998 CL LAKE GARDA, ITALY ID INTERFERENCE EXPERIMENT; NEUTRON INTERFEROMETRY; COMPLEMENTARITY; INFORMATION; ABSORPTION; COHERENCE; LIGHT; WAVE AB Interference may occur whenever there are two or more paths or processes leading to the same final outcome, and these are in principle indistinguishable. If one of these paths becomes labeled, yielding "which-path" information, interference will vanish. However, an appropriate measurement that "erases" the distinguishability may recover interference. Remarkably,, it can be recovered even in situations where there was no which-path information to erase! Using single photons in a modified Mach-Zehnder interferometer, we have investigated the various conditions that allow, prevent, and recover interference, for a variety of pure, mixed, and partially-mixed input states. C1 Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. RP Kwiat, PG (reprint author), Univ Calif Los Alamos Natl Lab, Div Phys, P-23,MS-H803, Los Alamos, NM 87545 USA. RI Englert, Berthold-Georg/G-2286-2012 OI Englert, Berthold-Georg/0000-0002-0690-927X NR 30 TC 4 Z9 4 U1 1 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-852-5 J9 AIP CONF PROC PY 1999 VL 461 BP 69 EP 80 DI 10.1063/1.57889 PG 12 WC Physics, Multidisciplinary; Physics, Particles & Fields SC Physics GA BM77T UT WOS:000079745500006 ER PT S AU White, AG Kwiat, PG James, DFV AF White, AG Kwiat, PG James, DFV BE Bonifacio, R TI "Interaction-free" measurements of quantum objects SO MYSTERIES, PUZZLES, AND PARADOXES IN QUANTUM MECHANICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Mysteries, Puzzles, and Paradoxes in Quantum Mechanics CY AUG-SEP -, 1998 CL LAKE GARDA, ITALY AB It is now well established that the presence of an opaque classical object can be unambiguously determined by an "interaction-free" measurement (IFM), where the object and the probe never directly interact. For quantum objects, we examine "interaction-free" measurement (the object wavefunction is unchanged) and "interaction-free" preparation (the object wavefunction is changed without physical interaction) and find that, in general, neither is possible. We propose using high efficiency IFM's as a quantum information bus to connect disjoint quantum systems. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP White, AG (reprint author), Univ Calif Los Alamos Natl Lab, P-23,MS-H803, Los Alamos, NM 87545 USA. RI James, Daniel/B-9805-2009 OI James, Daniel/0000-0003-3981-4602 NR 6 TC 4 Z9 4 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 1-56396-852-5 J9 AIP CONF PROC PY 1999 VL 461 BP 268 EP 271 DI 10.1063/1.57858 PG 4 WC Physics, Multidisciplinary; Physics, Particles & Fields SC Physics GA BM77T UT WOS:000079745500027 ER PT S AU Burkert, VD AF Burkert, VD BE Simula, S Safhai, B Mukhopadhyay, NC Burkert, VD TI Electromagnetic excitation of baryon resonances and the CLAS N* program. SO N(STAR) PHYSICS AND NONPERTURBATIVE QUANTUM CHROMODYNAMICS SE FEW-BODY SYSTEMS SUPPLEMENTUM LA English DT Proceedings Paper CT Workshop N(Star) Physics and Non-Perturbance QCD CY MAY 18-29, 1998 CL EUROPEAN CTR THEORET STUDIES & RELATED AREAS, TRENT, ITALY SP ECT, Italy, Jefferson Lab, US, CEA, Saclay HO EUROPEAN CTR THEORET STUDIES & RELATED AREAS ID QUARK-MODEL; ELECTROPRODUCTION AB The status of N* physics with electromagnetic probes is discussed. The experimental program with CLAS and first preliminary data are presented. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Burkert, VD (reprint author), Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 16 TC 8 Z9 8 U1 0 U2 0 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, A-1201 VIENNA, AUSTRIA SN 0177-8811 BN 3-211-83299-8 J9 FEW BODY SY PY 1999 VL 11 BP 1 EP 9 PG 9 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BN03E UT WOS:000080454700001 ER PT S AU Sandorfi, AM Hoblit, S Tonnison, J AF Sandorfi, AM Hoblit, S Tonnison, J BE Simula, S Safhai, B Mukhopadhyay, NC Burkert, VD TI Multipole Analyses for p(gamma,pi) and p(gamma,gamma) in the region of the P-33 Delta resonance SO N(STAR) PHYSICS AND NONPERTURBATIVE QUANTUM CHROMODYNAMICS SE FEW-BODY SYSTEMS SUPPLEMENTUM LA English DT Proceedings Paper CT Workshop N(Star) Physics and Non-Perturbance QCD CY MAY 18-29, 1998 CL EUROPEAN CTR THEORET STUDIES & RELATED AREAS, TRENT, ITALY SP ECT, Italy, Jefferson Lab, US, CEA, Saclay HO EUROPEAN CTR THEORET STUDIES & RELATED AREAS ID COMPTON-SCATTERING; MAGNETIC POLARIZABILITIES; PION-PHOTOPRODUCTION; PROTON; NUCLEON; PHOTONS; RATIO; MODEL AB Multipole analyses of the p(gamma, pi(0)), p(gamma, pi(+)) and p(gamma, gamma) reactions are carried out using different data sets. With sufficient constraints from polarization observables, the ratio of E2/M1 transition amplitudes for N --> Delta (EMR) appears to be largely insensitive to differences between recent p(gamma, pi(0)) cross section measurements. We deduce a current best estimate of EMR = -(2.85 +/- 0.34 +/- 0.21)%. Back angle Compton cross sections require a value for the backward spin polarizability delta(pi) that is significantly lower than previous expectations, with a magnitude that is coupled to the (gamma, pi) cross sections. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Sandorfi, AM (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 42 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, A-1201 VIENNA, AUSTRIA SN 0177-8811 BN 3-211-83299-8 J9 FEW BODY SY PY 1999 VL 11 BP 144 EP 156 PG 13 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BN03E UT WOS:000080454700025 ER PT S AU Lee, TSH AF Lee, TSH BE Simula, S Safhai, B Mukhopadhyay, NC Burkert, VD TI Theories of electromagnetic productions of pions SO N(STAR) PHYSICS AND NONPERTURBATIVE QUANTUM CHROMODYNAMICS SE FEW-BODY SYSTEMS SUPPLEMENTUM LA English DT Proceedings Paper CT Workshop N(Star) Physics and Non-Perturbance QCD CY MAY 18-29, 1998 CL EUROPEAN CTR THEORET STUDIES & RELATED AREAS, TRENT, ITALY SP ECT, Italy, Jefferson Lab, US, CEA, Saclay HO EUROPEAN CTR THEORET STUDIES & RELATED AREAS ID CONSTITUENT QUARK-MODEL; PHOTOPRODUCTION; BARYONS AB The current theoretical approaches for investigating the gamma N --> pi N and N(e,e'pi) reactions are reviewed. It is shown that the dynamical approach can be used to test the predictions from hadron structure calculations. Some N* form factors calculated using various chiral constituent quark models are presented. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Lee, TSH (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, A-1201 VIENNA, AUSTRIA SN 0177-8811 BN 3-211-83299-8 J9 FEW BODY SY PY 1999 VL 11 BP 157 EP 164 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BN03E UT WOS:000080454700026 ER PT B AU Clement, P Johnson, CD Sun, YW Klecka, GM Bartlett, C AF Clement, P Johnson, CD Sun, YW Klecka, GM Bartlett, C BE Alleman, BC Leeson, A TI Modeling natural attenuation of chlorinated solvent plumes at the Dover Air Force Base Area-6 site SO NATURAL ATTENUATION OF CHLORINATED SOLVENTS, PETROLEUM HYDROCARBONS, AND OTHER ORGANIC COMPOUNDS LA English DT Proceedings Paper CT 5th International In Situ and On-Site Bioremediation Symposium CY APR 19-22, 1999 CL SAN DIEGO, CA SP Battelle Mem Inst, Gas Res Inst, IT Grp Inc, Celtic Technol, Parsons Engn Sci Inc, U S Microb Inc, U S Naval Fac Engn Command, Waste Management Inc AB A multi-dimensional, multi-species reactive transport code, RT3D, was used to aid in the analysis of natural attenuation design at the Dover AFB Area-6 site. The RT3D code is a general-purpose numerical solver that can be used to solve any type of reactive transport systems by specifying a system-specific reaction model (Clement, 1997; Clement et al., 1998). In this study, a detailed biochemical reaction model was developed to simulate all aerobic and anaerobic reactions that occur at the Dover AFB site. The reactions were integrated into RT3D and the resulting numerical code was used to simulate the bioreactive transport occurring at the site. Through a model calibration process, field-scale decay rates of PCE/TCE and their degradation products were estimated. The calibrated model successfully recreated the observed distribution of PCE, TCE, DCE, VC and chloride plumes. A detailed sensitivity analysis of the calibrated model was also performed to study the uncertainties associated with the model parameters. The simulation model developed in this work is a useful framework for analyzing chlorinated-solvent natural attenuation data. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Clement, P (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999, Richland, WA 99352 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-074-8 PY 1999 BP 29 EP 34 PG 6 WC Environmental Sciences SC Environmental Sciences & Ecology GA BN62X UT WOS:000082416000005 ER PT S AU Bish, DL AF Bish, DL BE Misaelides, P Macasek, F Pinnavaia, TJ Colella, C TI Natural zeolites and nuclear-waste management: The case of Yucca Mountain, Nevada, USA SO NATURAL MICROPOROUS MATERIALS IN ENVIRONMENTAL TECHNOLOGY SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES E, APPLIED SCIENCES LA English DT Proceedings Paper CT Conference of the NATO Advanced Research Workshop on the Application of Natural Microporous Materials in Environmental Technology CY OCT 26-30, 1998 CL SMOLENICE CASTLE, SLOVAKIA SP NATO ID CLINOPTILOLITE; TUFF; EQUILIBRIUM; MINERALS AB The most important radionuclide migration issues at Yucca Mountain concern not Cs-137 and Sr-90 but anionic species and long-lived actinides that often form large, complex aqueous species. Zeolites do not interact strongly with such species, illustrating their limitations in real-world applications. Emplacement of radioactive waste will heat large volumes of rock, and zeolites will be important sources and sinks of water and thermal energy during heating and cooling in the vadose zone. In addition, dehydration/hydration reactions are accompanied by volumetric changes. Longer-term reactions, e.g., of clinoptilolite to analcime, will give rise to larger volume reductions and production of water and silica. These studies of Yucca Mountain show that the importance of zeolites extends far beyond cation exchange by zeolites to phenomena affecting the entire thermohydrologic system. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Bish, DL (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop D469, Los Alamos, NM 87545 USA. NR 16 TC 2 Z9 2 U1 0 U2 2 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0168-132X BN 0-7923-5888-0 J9 NATO ADV SCI I E-APP PY 1999 VL 362 BP 177 EP 191 PG 15 WC Chemistry, Analytical; Chemistry, Physical; Environmental Sciences; Materials Science, Multidisciplinary; Mineralogy SC Chemistry; Environmental Sciences & Ecology; Materials Science; Mineralogy GA BP45S UT WOS:000085199600012 ER PT S AU Navratil, JD AF Navratil, JD BE Misaelides, P Macasek, F Pinnavaia, TJ Colella, C TI Wastewater treatment technology based on iron oxides SO NATURAL MICROPOROUS MATERIALS IN ENVIRONMENTAL TECHNOLOGY SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES E, APPLIED SCIENCES LA English DT Proceedings Paper CT Conference of the NATO Advanced Research Workshop on the Application of Natural Microporous Materials in Environmental Technology CY OCT 26-30, 1998 CL SMOLENICE CASTLE, SLOVAKIA SP NATO AB Iron oxides have been used in a variety of forms for wastewater treatment. In most precipitation processes ferric ions are used to treat basic aqueous solutions by forming a ferric hydroxide flee to scavenge radioactive and heavy metal contaminants. In adsorption processes, a variety of iron containing minerals have been utilised. Since 1970, we have utilised ferrites and the mineral magnetite, iron ferrite (FeO . Fe2O3), for actinide and heavy metal removal from wastewater. Natural magnetite and ferrites, prepared in a variety of ways, were used in the batch mode to treat wastewaters. Magnetite was also supported and used in a column mode. In the presence of an external magnetic field, enhanced capacity was observed in using supported magnetite for removal of plutonium and americium from wastewater. This paper will review previous work on the use of ferrites and work in progress on supported magnetite (in a magnetic field) for wastewater treatment. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Navratil, JD (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 19 TC 1 Z9 1 U1 1 U2 2 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0168-132X BN 0-7923-5888-0 J9 NATO ADV SCI I E-APP PY 1999 VL 362 BP 417 EP 424 PG 8 WC Chemistry, Analytical; Chemistry, Physical; Environmental Sciences; Materials Science, Multidisciplinary; Mineralogy SC Chemistry; Environmental Sciences & Ecology; Materials Science; Mineralogy GA BP45S UT WOS:000085199600031 ER PT J AU Shayesteh, L Lu, YL Kuo, WL Baldocchi, R Godfrey, T Collins, C Pinkel, D Powell, B Mills, GB Gray, JW AF Shayesteh, L Lu, YL Kuo, WL Baldocchi, R Godfrey, T Collins, C Pinkel, D Powell, B Mills, GB Gray, JW TI PIK3CA is implicated as an oncogene in ovarian cancer SO NATURE GENETICS LA English DT Article ID PHOSPHATIDYLINOSITOL 3-KINASE; CELLS; OVERREPRESENTATION; TRANSFORMATION; HYBRIDIZATION; CARCINOMAS; APOPTOSIS; ADHESION; SURVIVAL; PATHWAY AB Ovarian cancer is the leading cause of death from gynecological malignancy and the fourth leading cause of cancer death among American women(1), yet little is known about its molecular aetiology. Studies using comparative genomic: hybridization (CGH) have revealed several regions of recurrent, abnormal, DNA sequence copy number(2-4) that may encode genes involved in the genesis or progression of the disease. One region at 3q26 found to be increased in copy number in approximately 40% of ovarian(2) and other(5) cancers contains PIK3CA, which encodes the p110 alpha catalytic subunit of phosphatidylinositol 3-kinase (PI3-kinase). The association between PIK3CA copy number and PI3-kinase activity makes PIK3CA a candidate oncogene because a broad range of cancer-related functions have been associated with PI3-kinase mediated signalling(6). These include proliferation(7), glucose transport and catabotism(8), cell adhesion(9), apoptosis(10), RAS signalling6 and oncogenic transformation(11-14). In addition, downstream effecters of Pl3-kinase, AKT1 and AKR, have been found to be amplified(15,16) or activated(17) in human tumours, including ovarian cancer. We show here that PIK3CA is frequently increased in copy number in ovarian cancers, that the increased copy number is associated with increased PIK3CA transcription, p110 alpha protein expression and PO-kinase activity and that treatment with the PI3-kinase inhibitor LY294002 decreases proliferation and increases apoptosis. Our observations suggest PIK3CA is an oncogene that has an important role in ovarian cancer. C1 Univ Calif San Francisco, Ctr Canc, San Francisco, CA USA. Univ Texas, Md Anderson Canc Ctr, Houston, TX 77030 USA. Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94702 USA. RP Gray, JW (reprint author), Univ Calif San Francisco, Ctr Canc, San Francisco, CA USA. EM gray@cc.ucsf.edu RI Godfrey, Tony/A-5572-2013 OI Godfrey, Tony/0000-0002-3283-6983 FU NCI NIH HHS [CA09215, P01-CA64602] NR 34 TC 853 Z9 885 U1 3 U2 24 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1061-4036 J9 NAT GENET JI Nature Genet. PD JAN PY 1999 VL 21 IS 1 BP 99 EP 102 DI 10.1038/5042 PG 4 WC Genetics & Heredity SC Genetics & Heredity GA 155RT UT WOS:000077960700017 PM 9916799 ER PT J AU Bixby, KA Nanao, MH Shen, NV Kreusch, A Bellamy, H Pfaffinger, PJ Choe, S AF Bixby, KA Nanao, MH Shen, NV Kreusch, A Bellamy, H Pfaffinger, PJ Choe, S TI Zn2+-binding and molecular determinants of tetramerization in voltage-gated K+ channels SO NATURE STRUCTURAL BIOLOGY LA English DT Article ID POTASSIUM-CHANNEL; SHAKER; DROSOPHILA; PROTEINS; DIVERSITY; GENE; RECEPTOR; SUBUNITS; BINDING; DOMAIN AB The N-terminal, cytoplasmic tetramerization domain (T1) of voltage-gated K+ channels encodes molecular determinants for subfamily-specific assembly of a-subunits into functional tetrameric channels. Crystal structures of T1 tetramers from Shaw and Shaker subfamilies reveal a common four-layered scaffolding. Within layer 4, on the hypothetical membrane-facing side of the tetramer, the Shaw TI tetramer contains four zinc ions; each is coordinated by a histidine and two cysteines from one monomer and by one cysteine from an adjacent monomer. The amino acids involved in coordinating the Zn2+ ion occur in a HX5CX20CC sequence motif that is highly conserved among all Shah, Shaw and Shal subfamily members, but is not found in Shaker subfamily members. We demonstrate by coimmunoprecipitation that a few characteristic residues in the subunit interface are crucial for subfamily-specific tetramerization of the T1 domains. C1 Salk Inst Biol Studies, Struct Biol Lab, La Jolla, CA 92037 USA. Univ Calif San Diego, Dept Chem & Biochem, La Jolla, CA 92037 USA. Univ Calif San Diego, Dept Biol, La Jolla, CA 92037 USA. Baylor Coll Med, Div Neurosci, Houston, TX 77030 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Choe, S (reprint author), Salk Inst Biol Studies, Struct Biol Lab, 10010 N Torrey Pines Rd, La Jolla, CA 92037 USA. NR 39 TC 135 Z9 137 U1 0 U2 3 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1072-8368 J9 NAT STRUCT BIOL JI Nat. Struct. Biol. PD JAN PY 1999 VL 6 IS 1 BP 38 EP 43 PG 6 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 153FA UT WOS:000077821000012 PM 9886290 ER PT S AU Ramanathan, K Wiesner, H Asher, S Bhattacharya, RN Keane, J Contreras, MA Noufi, R AF Ramanathan, K Wiesner, H Asher, S Bhattacharya, RN Keane, J Contreras, MA Noufi, R BE AlJassim, M Thornton, JP TI Junction formation in CuInSe2-based thin-film devices SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID SOLAR-CELLS AB The nature of the interface between CuInSe2 (CLS) and the chemical bath deposited CdS layer has been investigated. We show that heat-treating the absorbers in Cd- or Zn-containing solutions in the presence of ammonium hydroxide sets up a chemical reaction which facilitates an extraction of Cu from the lattice and an in-diffusion of Cd. The characteristics of devices made in this manner suggest that the reaction generates a thin, n-doped region in the absorber. It is quite possible that the CdS/CuInSe2 device is a buried, shallow junction with a CdS window layer, rather than a heterojunction. We have used these ideas to develop methods for fabricating devices without CdS or Cd. A 14.2% efficiency ZnO/CIGS device was obtained through aqueous treatment in Zn solutions. C1 Natl Ctr Photovolta, Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Ramanathan, K (reprint author), Natl Ctr Photovolta, Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 12 TC 2 Z9 2 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 9 EP 16 PG 8 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900002 ER PT S AU Wu, X Sheldon, P Mahathongdy, Y Ribelin, R Mason, A Moutinho, HR Coutts, TJ AF Wu, X Sheldon, P Mahathongdy, Y Ribelin, R Mason, A Moutinho, HR Coutts, TJ BE AlJassim, M Thornton, JP TI CdS/CdTe thin-film solar cell with a zinc stannate buffer layer SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB This paper describes an improved CdS/CdTe polycrystalline thin-film solar-cell device structure that integrates st zinc stannate (Zn2SnO4 or ZTO) buffer layer between the transparent conductive oxide (TCO) layer and the CdS window layer. Zinc stannate films have a high bandgap, high transmittance, low absorptance, and low surface roughness. In addition, these films are chemically stable and exhibit higher resistivities that are roughly matched to that of the CdS window layer in the device structure. Preliminary device results have demonstrated that by integrating a ZTO buffer layer in both SnO2-based and Cd2SnO4 (CTO)-based CdS/CdTe devices, performance and reproducibility can be significantly enhanced. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wu, X (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 4 TC 5 Z9 5 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 37 EP 41 PG 5 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900006 ER PT S AU McMahon, TJ Jorgensen, GJ AF McMahon, TJ Jorgensen, GJ BE AlJassim, M Thornton, JP TI Progress toward a CdTe cell life prediction SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB In this paper, we review the progress made by the CdTe Thin Film Partnership Reliability Team in developing an accelerated environmental test (AET) methodology that Hill indicate the expected life of CdTe cells incorporated in a module operated in the field. The primary focus is on test design? cell reliability, and the correlation of indoor accelerated testing dth outdoor exposure. The team has emphasized cell-stability issues, and is not examining failure modes such as those involving module packaging. junction boxes, and mounting. The goal is to develop a CdTe cell technology with a 30 yr life, and verify that reliability through AETs. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP McMahon, TJ (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 12 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 54 EP 61 PG 8 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900009 ER PT S AU Zhang, SB Wei, SH Zunger, A AF Zhang, SB Wei, SH Zunger, A BE AlJassim, M Thornton, JP TI Elements of doping engineering in semiconductors SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID II-VI; ENERGIES; GAAS AB Using defect thermodynamics, we discuss physical factors that affect doping limits in semiconductors. The dependencies of the defect formation enthalpy on the atomic chemical potentials and on the electron Fermi energy are demonstrated. These dependencies, in particular on the Fermi energy, lead to spontaneous formation of charge-compensating defects that can limit doping. Experimental data compiled for III-V, II-VT, and I-III-VI2 compounds support this view and further provide insight into the connections among different host materials. We argue that what matters is not the magnitude of the band gap that determines the dopability of a material, but rather, the relative position of the conduction-band minimum (in the case of n-doping) and the valence-band maximum (in the case of p-doping) with respect to vacuum. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Zhang, SB (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Krausnick, Jennifer/D-6291-2013; Zhang, Shengbai/D-4885-2013 OI Zhang, Shengbai/0000-0003-0833-5860 NR 10 TC 1 Z9 1 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 62 EP 69 PG 8 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900010 ER PT S AU Branz, HM AF Branz, HM BE AlJassim, M Thornton, JP TI New microscopic model of the Staebler-Wronski effect in hydrogenated amorphous silicon SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID MECHANISM; DIFFUSION AB A new microscopic and kinetic model of light-induced metastability in hydrogenated amorphous silicon (a-Si:H) was recently proposed. Carrier recombination excites H from deep Si-H bonds into a mobile configuration, leaving a threefold-coordinate Si dangling bond (DB) defect at the site of excitation - a process long suspected to be an element of metastable DB production. Normally, mobile H are recaptured at DB defects and neither metastability nor net DB production results. However, when two mobile H collide, they form a metastable two-hydrogen complex and leave two spatially-uncorrelated Staebler-Wronski DBs. The model leads to differential equations describing the evolution of the mobile H and DB densities and a variety of new predictions. New directions for improving the stability of a-Si:H are discussed. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Branz, HM (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 10 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 79 EP 81 PG 3 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900012 ER PT S AU Asher, SE Ramanathan, K Niles, DW Wiesner, H Moutinho, H AF Asher, SE Ramanathan, K Niles, DW Wiesner, H Moutinho, H BE AlJassim, M Thornton, JP TI Surface analytical study of CuInSe2 treated in Cd-containing partial electrolyte solution SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB Junction formation in CuInSe2 (CIS) has been studied by exposing thin films and single-crystal samples to solutions containing NH4OH and CdSO4. The treated samples were analyzed by secondary ion mass spectrometry to determine the amount and distribution of Cd deposited on the surface of the films. Cadmium is found to react with the surface for all the solution exposure times and temperatures studied. The reaction rapidly approaches the endpoint and remains relatively unchanged for subsequent solution exposure. Cadmium in-diffusion, as measured by secondary ion mass spectrometry, is obscured by topography effects in the thin-film samples and by ion-beam mixing and topography in the single-crystal sample. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Asher, SE (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 4 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 126 EP 131 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900020 ER PT S AU Schulz, DL Ribelin, R Curtis, CJ Ginley, DS AF Schulz, DL Ribelin, R Curtis, CJ Ginley, DS BE AlJassim, M Thornton, JP TI Particulate contacts to Si and CdTe: Al, Ag, Hg-Cu-Te, and Sb-Te SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB Our team has been investigating the use of particle-based contacts in both Si and CdTe solar cell technologies. First, in the area of contacts to Si, powders of Al and Ag prepared by an electroexplosion process have been characterized by transmission electron microscopy (TEM), TEM elemental determination X-ray spectroscopy (TEM-EDS), and TEM electron diffraction (TEM-ED). These Al and Ag particles were slurried and tested as contacts to p- and n-type silicon wafers, respectively. Linear current-voltage (I-V) was observed for Ag on n-type Si, indicative of an ohmic contact, whereas the Al on p-type Si sample was non-ideal. A wet-chemical surface treatment was performed on one Al sample and TEM-EDS indicated a substantial decrease in the O contaminant level. The treated Al on P-type Si films exhibited linear I-V after annealing. Second, in the area of contacts to CdTe, particles of Hg-Cu-Te and Sb-Te have been applied as contacts to CdTe/CdS/SnO2 heterostructures prepared by the standard NREL protocol, First, Hs-Cu-Te and Sb-Te were prepared by a metathesis reaction. Alter CdCl2 treatment and NP etch of the CdTe layer, particle contacts were applied. The Hg-Cu-Te contacted cells exhibited good electrical characteristics, with V-oc > 810 mV and efficiencies > 11.5 % for most cells. Although V-oc > 800 mV were observed for the Sb-Te contacted cells, efficiencies in these devices were limited to 9.1%, presumably by it large series resistance (>20 Omega) observed in all samples. C1 Natl Renewable Energy Lab, Photovoltaic & Elect Mat Ctr, Golden, CO 80401 USA. RP Schulz, DL (reprint author), Natl Renewable Energy Lab, Photovoltaic & Elect Mat Ctr, Golden, CO 80401 USA. NR 3 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 206 EP 211 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900033 ER PT S AU Li, X Ribelin, R Mahathongdy, Y Albin, D Dhere, R Rose, D Asher, S Moutinho, H Sheldon, P AF Li, X Ribelin, R Mahathongdy, Y Albin, D Dhere, R Rose, D Asher, S Moutinho, H Sheldon, P BE AlJassim, M Thornton, JP TI The effect of high-resistance SnO(2) on CdS/CdTe device performance SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP Conference Proceedings LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB nIn this paper, we have studied the effect of high-resistance SnO(2) buffer layers, deposited by low-pressure chemical-vapor deposition on Cds/CdTe device performance. Our results indicate that when CdS/CdTe devices have a very thin layer of CdS or no CdS at all, the i-SnO(2) buffer layer helps to increase device effciency. When the CdS layer is thicker than 600 Angstrom, the device performance is dominated by CdS thickness, not the i-SnO(2) layer. If a very thin CdS layer is to be used to enhance device performance. we conclude that a better SnO(2) buffer layer is needed.In this paper, we have studied the effect of high-resistance SnO(2) buffer layers, deposited by low-pressure chemical-vapor deposition on Cds/CdTe device performance. Our results indicate that when CdS/CdTe devices have a very thin layer of CdS or no CdS at all, the i-SnO(2) buffer layer helps to increase device efficiency. When the CdS layer is thicker than 600 Angstrom, the device performance is dominated by CdS thickness, not the i-SnO(2) layer. If a very thin CdS layer is to be used to enhance device performance. we conclude that a better SnO(2) buffer layer is needed. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Li, X (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM xli@nrel.gov; rosine+ribelin@nrel.gov; ymahatho@nrel.gov; rahere@nrel.nrel.gov; solar.cells@accesstoledo.com; sally_asher@nrel.gov; helio_moutinho@nrel.gov; peter_sheldon@nrel.gov NR 3 TC 9 Z9 9 U1 2 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 230 EP 235 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900037 ER PT S AU Mahathongdy, Y Albin, DS Wolden, CA Baldwin, RM AF Mahathongdy, Y Albin, DS Wolden, CA Baldwin, RM BE AlJassim, M Thornton, JP TI Vapor CdCl2-optimization and screening experiments for an all dry chloride treatment of CdS/CdTe solar cells SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB A dry vapor treatment of CdCl2 is being developed as an alternative approach to the conventional solution CdCl2 treatment of CdS/CdTe devices. In this alternative process, the CdS/CdTe substrates are vapor treated in a close-spaced sublimation configuration. A 16-run Plackett-Burman screening experiment identified source temperature, substrate temperature, and treatment time as being the most significant parameters in the process, Subsequently, a 20-run Central Composite Design showed that a source temperature of 380-390 degrees C a temperature gradient (Delta T) of 5 degrees C, and a time of 10 minutes provides the most process tolerant combination, yielding a total-area efficiency of 12.6%. A strong interaction between Delta T and treatment time was also identified. The modal indicated that for a small Delta T. device performance improved with decreasing time, whereas at larger values of Delta T, performance increased with increasing time. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Mahathongdy, Y (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 12 TC 2 Z9 2 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 236 EP 241 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900038 ER PT S AU Dhere, RG Moutinho, HR Asher, S Young, D Li, X Ribelin, R Gessert, T AF Dhere, RG Moutinho, HR Asher, S Young, D Li, X Ribelin, R Gessert, T BE AlJassim, M Thornton, JP TI Characterization of SnO2 films prepared using tin tetrachloride and tetra methyl tin precursors SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB We have investigated the effect of deposition conditions of SnO2 films, deposited by chemical vapor deposition using tin tetrachloride and tetramethyltin precursors, on the film properties. The type of precursor and the deposition temperature affect the morphology of the films. The structure of the films is determined by the deposition temperature: films deposited at low temperatures show a mixed SnO and SnO2 phase. The processing temperature and type of substrate determine the impurity content in the films. Electrical properties (e.g, the carrier mobility) and optical properties of the films are affected by the structure and the impurity content in these layers. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Dhere, RG (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 1 TC 5 Z9 5 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 242 EP 247 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900039 ER PT S AU Narayanswamy, C Gessert, TA Asher, SE AF Narayanswamy, C Gessert, TA Asher, SE BE AlJassim, M Thornton, JP TI Analysis of Cu diffusion in ZnTe-based contacts for thin-film CdS/CdTe solar cells SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID BACK CONTACTS AB Ohmic contacts to thin-film CdS/CdTe phetovoltaic devices have been formed using a two-layer contact interface of undoped ZnTe (ZnTe) and Cu-doped ZnTe (ZnTe:Cu), followed by Ni or Ti as an outer metallization. Secondary ion mass spectroscopy(SIMS) is used to study Cu diffusion within this back-contact structure, and also, to monitor Cu diffusion from the contact into the CdTe. When Ni metallization is used, the ZnTe:Cu layer becomes increasingly depleted of Cu, and Ni diffusion into the ZnTe:Cu increases as the contact deposition temperature increases from 100 degrees C to 300 degrees C. Cu depletion is not observed when Ni is replaced with Ti. Diffusion of Cu from the ZnTe:Cu layer into the ZnTe layer also increases with contact deposition temperature, and produces a buildup of Cu at the ZnTe/CdTe interface. High-mass resolution SIMS indicates that. although Cu levels in the CdTe remain low, Cu diffusion from the contact proceeds into the CdTe layer and toward the CdTe/CdS junction region. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Narayanswamy, C (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 9 TC 7 Z9 7 U1 1 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 248 EP 253 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900040 ER PT S AU Mahan, AH Reedy, RC Iwaniczko, E Wang, Q Nelson, BP Xu, Y Gallagher, AC Branz, HM Crandall, RS Yang, J Guha, S AF Mahan, AH Reedy, RC Iwaniczko, E Wang, Q Nelson, BP Xu, Y Gallagher, AC Branz, HM Crandall, RS Yang, J Guha, S BE AlJassim, M Thornton, JP TI H out-diffusion and device performance in n-i-p solar cells using high temperature hot wire a-Si : H i-layers SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID HYDROGENATED AMORPHOUS-SILICON AB Hydrogen out-diffusion from the n/i interface region plays a major role in controlling the fill factor (FF) and resultant efficiency of n-i-p a-Si:H devices, with the i-layer deposited at high substrate temperatures by the hot wire technique. Modeling calculations have shown that a thin, highly defective layer at this interface, perhaps caused by significant a out-diffusion and incomplete lattice reconstruction, results in sharply lower device FFs due to the large voltage dropped across this defective layer We have therefore employed buffer layers designed to retard this out-diffusion. We find that an increased H content, either in the n-layer or a thin intrinsic low temperature buffer layer, does not significantly retard this out-diffusion, as observed by SIMS H profiles on devices. However, if this low temperature buffer layer is thick enough, the out-diffusion is minimized, yielding nearly flat H profiles and a much improved device performance. We discuss this behavior in the context of the H chemical potentials and H diffusion coefficients in the high temperature, buffer, n-, and stainless steel substrate layers. Finally, we report a 9.8% initial active area device, fabricated at 16.5 Angstrom/s, using the insights obtained in this study. Light soaking data are also reported. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Mahan, AH (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 16 TC 16 Z9 16 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 285 EP 290 DI 10.1117/12.357646 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900046 ER PT S AU Sopori, BL Madjdpour, J Chen, W Zhang, Y AF Sopori, BL Madjdpour, J Chen, W Zhang, Y BE AlJassim, M Thornton, JP TI Light-trapping in a-Si solar cells: A summary of the results from PV Optics SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB This paper describes major features of a new optical software package, PV Optics, and presents a brief summary of the results of applying this program to analyze amorphous silicon solar cells. Some examples are given, mainly to demonstrate the nature of calculations that can be performed with this program for a-Si cell design. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Sopori, BL (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 3 TC 2 Z9 2 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 291 EP 296 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900047 ER PT S AU McConnell, RD AF McConnell, RD BE AlJassim, M Thornton, JP TI Results from undergraduate PV projects at seven historically black colleges and universities SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB In 1995, the NREL/Department of Energy (DOE) National Photovoltaics Program funded seven Historically Black Colleges and Universities (HBCUs) in its HBCU Photovoltaic Research Associates Program for a period of three years. The program's purpose is to advance HBCU undergraduate knowledge of photovoltaics, primarily as a result of research investigations performed, and to encourage students to pursue careers in photovoltaics. This paper presents results from PV projects ranging from fundamental materials research on PV materials to field projects of PV systems. C1 Natl Renewable Energy Lab, Ctr Basic Sci, Golden, CO 80401 USA. RP McConnell, RD (reprint author), Natl Renewable Energy Lab, Ctr Basic Sci, Golden, CO 80401 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 325 EP 331 PG 7 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900053 ER PT S AU Fthenakis, VM Moskowitz, PD AF Fthenakis, VM Moskowitz, PD BE AlJassim, M Thornton, JP TI The value and feasibility of proactive recycling SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB Photovoltaics (PV) technology has definite environmental advantages over competing electricity generation technologies, and so far these advantages have driven market penetration. The PV industry follows a pro-active approach to present its safe and environmentally friendly nature. Industrial ecology considerations raise the issue of what to do with the PV modules at the end of their useful tife. One option is recycling. This paper discusses the value of proactive recycling and compares several alternatives. C1 Brookhaven Natl Lab, Environm & Waste Technol Ctr, Upton, NY 11973 USA. RP Fthenakis, VM (reprint author), Brookhaven Natl Lab, Environm & Waste Technol Ctr, Upton, NY 11973 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 332 EP 337 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900054 ER PT S AU Sopori, B Chen, W Tan, T Plekhanov, P AF Sopori, B Chen, W Tan, T Plekhanov, P BE AlJassim, M Thornton, JP TI Overcoming the efficiency-limiting mechanisms in commercial Si solar cells SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB A brief review of performance-limiting processes in a commercial solar cell fabricated on low-cost substrate is given. Higher efficiencies require effective gettering of precipitated impurities present at the defect clusters, and improved cell and process designs. Overcoming these limitations is expected to lead to 18%-20 % cell efficiencies. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Sopori, B (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 6 TC 1 Z9 2 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 341 EP 347 PG 7 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900055 ER PT S AU Gee, JM Smith, DD Garrett, SE Bode, MD Jimeno, JC AF Gee, JM Smith, DD Garrett, SE Bode, MD Jimeno, JC BE AlJassim, M Thornton, JP TI Back-contact crystalline-silicon solar cells and modules SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB This paper summarizes recent progress in the development of back-contact crystalline-silicon (c-Si) solar cells and modules at Sandia National Laboratories. Back-contact cells have potentially improved efficiencies through the elimination of grid obscuration and allow for significant simplifications in the module assembly process. Optimization of the process sequence has improved the efficiency of our back-contact cell ("emitter wrap through") from around 12% to near 17% in the past 12 months. In addition recent theoretical work has elucidated the device physics of emitter wrap-through cells. Finally, improvements in the assembly process using back-contact cells art described. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Gee, JM (reprint author), Sandia Natl Labs, POB 5800,MS-0752, Albuquerque, NM 87185 USA. NR 4 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 348 EP 353 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900056 ER PT S AU Geisz, JF Friedman, DJ Olson, JM Kramer, C Kibbler, A Kurtz, SR AF Geisz, JF Friedman, DJ Olson, JM Kramer, C Kibbler, A Kurtz, SR BE AlJassim, M Thornton, JP TI New materials for future generations of III-V solar cells SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID TANDEM AB Three- and four-junction III-V devices are proposed for ultrahigh-efficiency solar cells using a new 1-eV material lattice-matched to GaAs, namely, GaInNAs. We demonstrate working prototypes of a GaInNAs-based solar cell lattice-matched to GaAs with photoresponse down to I eV. Under the AM1.5 direct spectrum with ail the light higher in energy than the GaAs band gap filtered out, the prototypes grown with base doping of about 10(17) cm(-3) have open-circuit voltages ranging from 0.35 to 0.44 V, short-circuit current densities of 1.8 mA/cm(2), and fill factors from 61% to 66%. To improve on the current record-efficiency tandem GaInP/GaAs solar cell by adding a GaInNAs junction, the short-circuit current density elf this 1-eV cell must be significantly increased. Because there low short-circuit current densities are due to short diffusion lengths. we have demonstrated a depletion-width-enhanced variation of one of the prototype devices that trades off decreased voltage for increased photocurrent, with a short-circuit current density of 7.4 mA/cm(2) and an open-circuit voltage of 0.28 V. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Geisz, JF (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 8 TC 1 Z9 1 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 372 EP 377 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900059 ER PT S AU Kurtz, SR Friedman, DJ AF Kurtz, SR Friedman, DJ BE AlJassim, M Thornton, JP TI Concentrator and space applications of high-efficiency solar cells - Recent developments SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID SCARLET AB GaInP/GaAs cells invented and developed at NREL have achieved world-record efficiencies. We estimate that their production for space applications has grown to > $100 million/yr. Approximately 300 MW/yr of 1000X terrestrial concentrator cells could be fabricated with the existing manufacturing capacity at a cost of about 21 cent/Wp. A resurgence of interest in terrestrial PV concentrators, together with the strength of the m-V space-solar-cell industry, indicate that m-v cells are also attractive for terrestrial applications. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kurtz, SR (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 32 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 378 EP 384 PG 7 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900060 ER PT S AU Ward, JS Duda, A Coutts, TJ Kurtz, SR AF Ward, JS Duda, A Coutts, TJ Kurtz, SR BE AlJassim, M Thornton, JP TI New concepts for high-intensity PV modules for use with dish concentrator systems SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP Conference Proceedings LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB In this paper we report on our efforts to fabricate monolithically interconnected modules (MIMs) from GaAs device structures. The small size of the component cells comprising the MIM allows for operation at very high flux densities. This relaxes the requirement for a small spot-size to be generated by the optics. The devices are grown on semi-insulating substrates, allowing the incorporation of an extremely efficient back surface reflector (BSR). This BSR is an effective tool for thermal management of the array. The possibility of using this device configuration in conjuction with the large dish concentrators developed by the solar thermal community is examined. The advantages of using multijunction devices for this application is also discussed. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Ward, JS (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM scott_ward@nrel.gov; anna_duda@nrel.gov; tim_coutts@nrel.gov; sarah_kurtz@nrel.gov NR 9 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 385 EP 392 PG 8 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900061 ER PT S AU McMahon, WE Olson, JM AF McMahon, WE Olson, JM BE AlJassim, M Thornton, JP TI Surface science in an MOCVD environment: Arsenic on vicinal Ge(100) SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID ANTIPHASE DOMAINS; GROWTH; STEPS; EPITAXY; GAAS AB Scanning tunneling microscope (STM) images of arsine-exposed vicinal Ge(100) surfaces show that most As/Ge steps are reconstructed and that a variety of different step structures exist. The entire family of reconstructed As/Ge steps can be divided into two types, which we have chosen to call "single-row" steps and "double-row" steps. In this paper we propose a model for a double-row step created by annealing a vicinal Ge(100) substrate under an arsine flux in a metal-organic chemical vapor deposition (MOCVD) chamber. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP McMahon, WE (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 395 EP 400 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900062 ER PT S AU Friedman, DJ Kurtz, SR Kibbler, AE AF Friedman, DJ Kurtz, SR Kibbler, AE BE AlJassim, M Thornton, JP TI Exploration of GaInTlP and related Tl-containing III-V alloys for photovoltaics SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID MOLECULAR-BEAM EPITAXY; SOURCE MBE GROWTH; TLINGAP; DEVICES AB This paper discusses the results of an attempt to grow GaInTlP for application as a 1-eV material for the third junction of a GaInP/GaAs/3rd-junction high-efficiency solar cell. Although early indications from the literature were promising, we are unable to produce crystalline homogeneous material, and so we conclude that this material is not a promising candidate for such applications as photovoltaics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Friedman, DJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 13 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 401 EP 405 PG 5 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900063 ER PT S AU Ruby, DS Yang, P Zaidi, S Brueck, S Roy, M Narayanan, S AF Ruby, DS Yang, P Zaidi, S Brueck, S Roy, M Narayanan, S BE AlJassim, M Thornton, JP TI Plasma etching, texturing, and passivation of silicon solar cells SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB We improved a self-aligned emitter etchback technique that requires only a single emitter diffusion and no alignments to form self-aligned, patterned-emitter profiles. Standard commercial screen-printed gridlines mask a plasma-etchback of the emitter. A subsequent PECVD-nitride deposition provides good surface and bulk passivation and an antireflection coating. We used full-size multicrystalline silicon (mc-Si) cells processed in a commercial production line and performed a statistically designed multiparameter experiment to optimize the use of a hydrogenation treatment to increase performance. We obtained an improvement of almost a full percentage point in cell efficiency when the self-aligned emitter etchback was combined with an optimized 3-step PECVD-nitride surface passivation and hydrogenation treatment. We also investigated the inclusion of a plasma-etching process that results in a low-reflectance, textured surface on multicrystalline silicon cells. Preliminary results indicate reflectance can be significantly reduced without etching away the emitter diffusion. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ruby, DS (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 430 EP 436 PG 7 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900068 ER PT S AU Sopori, B Chen, W Zhang, Y AF Sopori, B Chen, W Zhang, Y BE AlJassim, M Thornton, JP TI Development of a thin-film crystalline-silicon solar cell SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID SI AB A new design for a single junction, thin film Si solar cell is presented. The cell design is compatible with low-temperature processing required for the use of a low-cost glass substrate, and includes effective light trapping and impurity gettering. Elements of essential process steps are discussed. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Sopori, B (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 16 TC 1 Z9 1 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 437 EP 442 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900069 ER PT S AU Wang, TH Ciszek, TF Landry, M Matthaus, A Mihalik, G AF Wang, TH Ciszek, TF Landry, M Matthaus, A Mihalik, G BE AlJassim, M Thornton, JP TI A silicon ingot lifetime tester for industrial use SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB A specially designed lifetime measurement instrument has been developed to characterize silicon ingots before they are subjected to expensive slicing and solar-cell processing, thereby saving needless processing costs of inferior materials in a solar-cell production line. The instrument uses the direct-current photoconductance decay (DC-PCD) method for linear detection of the transient photoconductance signal and localized probing / illumination for necessary sensitivity on low resistivity and large samples. The instrument also has a compact and high-power laser diode as the light source, data averaging capability, a pneumatic ingot transport and probe positioning mechanism, and a user-friendly graphical interface for data acquisition / lifetime calculation / data storage / hardcopy for factory-floor use with quick turnaround. A 3-dimensional finite-element analysis indicates that the as-cut surface finish is adequate for measuring the bulk lifetime on the order of 50 mu s or less. Measurement repeatability and clear distinction among different grades of feedstock materials have been demonstrated. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wang, TH (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 3 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 443 EP 452 PG 10 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900070 ER PT S AU Tsuo, YS Menna, P Wang, TH Ciszek, TF AF Tsuo, YS Menna, P Wang, TH Ciszek, TF BE AlJassim, M Thornton, JP TI New opportunities in crystalline silicon R&D SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB To support the expected growth of the silicon solar cell industry, we believe that research and development (R&D) activities should be carried out in the following areas: polysilicon feedstock for the PV industry; thin-layer silicon deposition methods, and more environmentally benign cell and module manufacturing processes. For each of these activities, we identify the main issues that needed to be addressed. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Tsuo, YS (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 5 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 453 EP 458 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900071 ER PT S AU Levi, DH Woods, LM Albin, DS Gessert, TA AF Levi, DH Woods, LM Albin, DS Gessert, TA BE AlJassim, M Thornton, JP TI Back contact effects on the electro-optical properties of CdTe/CdS solar cells SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB Studies of junction photoluminescence (PL) in CdTe/CdS solar cells reveal that back-contact application produces a dramatic qualitative change in the junction picosecond-PL spectrum. Prior to contact application, the spectrum has two peaks at energies of 1.501 eV and 1.457 eV, corresponding to recombination in regions of CdTeS alloy with 2% and 12% sulfur content, respectively. After contact application, the spectrum consists of a single broad peak at 1.48 eV. Previous studies have shown that the nitric-phosphoric (NP) etch used in the contact procedure produces a layer of elemental tellurium (Te) on the CdTe surface. We postulate that the change in the near-junction PL spectrum is caused by a grain-boundary field effect due to perturbations of the grain-boundary conductivity and Fermi level. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Levi, DH (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 8 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 461 EP 466 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900072 ER PT S AU Smith, S Cheong, HM Fluegel, BD Geisz, JF Olson, JM Dhere, R Kazmerski, LL Mascarenhas, A AF Smith, S Cheong, HM Fluegel, BD Geisz, JF Olson, JM Dhere, R Kazmerski, LL Mascarenhas, A BE AlJassim, M Thornton, JP TI Excitons and recombination in photovoltaic materials SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID ORDERED GAINP2; ALLOYS AB High spatial resolution (similar to 0.7 mu m) scanning confocal microscopy, combined with low-temperature (5 K) photoluminescence (PL) spectroscopy, can be used to probe the spatial variations in the spectral properties of photovoltaic materials with sub-micron spatial resolution (similar to 0.7 mu m). We report on the successful demonstration of this technique applied to two particular photovoltaic systems: a partially ordered GaInP2 epilayer, and a released (exposing the CdTe/CdS interface) polycrystalline CdTe film. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Smith, S (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Cheong, Hyeonsik/D-7424-2012 OI Cheong, Hyeonsik/0000-0002-2347-4044 NR 4 TC 0 Z9 0 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 467 EP 472 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900073 ER PT S AU Deb, SK Ellingson, R Ferrere, S Frank, AJ Gregg, BA Nozik, AJ Park, N Schlichthorl, G Zaban, A AF Deb, SK Ellingson, R Ferrere, S Frank, AJ Gregg, BA Nozik, AJ Park, N Schlichthorl, G Zaban, A BE AlJassim, M Thornton, JP TI Photochemical solar cells based on dye-sensitization of nanocrystalline TiO2 SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID TITANIUM-DIOXIDE FILMS; ARTIFICIAL PHOTOSYNTHESIS; ELECTRON INJECTION; CONVERSION; PHOTOSENSITIZATION; EFFICIENCIES; ELECTRICITY; SEPARATION; STATES; OUTPUT AB A photoelectrochemical solar cell that is based on the dye-sensitization of thin nanocrystalline films of TiO2 (anatase) nanoparticles in contact with a non-aqueous liquid electrolyte is described. The cell, fabricated at NREL, shows a conversion efficiency of similar to 9.2% at AM1.5, which approaches the best reported value of 10%-11% by Gratzel at EPFL in Lausanne, Switzerland. Femtosecond(fs) pump-probe spectroscopy has been used to time resolve the injection of electrons into the conduction band of nanocrystalline TiO2 films under ambient conditions following photoexcitation of the adsorbed Ru(II)-complex dye. The measurement indicates an instrument-limited -50 fs upper limit on the electron injection time. We also report the sensitization of nanocrystalline TiO2 by a novel iron-based dye, cis-[Fe-II(2,2'-bipyridine-4,4'-dicarboxylic acid)(2)(CN)(2)], a chromophore with an extremely short-lived, nonemissive excited state. The dye also exhibits a unique "band selective" sensitization through one of its two absorption bands. The operational principle of the device has been studied through the measurement of electric field distribution within the device structure and studies on the pH dependence of dye-redox potential. The incorporation of a WO3-based electrochromic layer into this device has led to a novel photoelectrochromic device structure for "smart window'' applications. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Deb, SK (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Ellingson, Randy/H-3424-2013 NR 27 TC 0 Z9 0 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 473 EP 480 PG 8 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900074 ER PT S AU Ahrenkiel, RK Johnston, SW AF Ahrenkiel, RK Johnston, SW BE AlJassim, M Thornton, JP TI Large-signal injection-level spectroscopy of impurities in silicon SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP Conference Proceedings LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID MINORITY-CARRIER LIFETIME; SEMICONDUCTORS AB Deep lever defects in silicon are identified by measuring the recombination lifetime as a function of the injection level. The basic models for recombination at deep and shallow centers is developed. The defect used for the theoretical model is the well-known interstitial Fe ion in silicon. Data are presented on silicon samples ranging in defect content from intentionally Fe-doped samples to an ultra-pure float-zone grown sample. These data are analyzed in terms of the injection-level spectroscopy model. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM richard_ahrenkiel@nrel.gov; steve_johnston@nrel.gov NR 18 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 483 EP 491 PG 9 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900075 ER PT S AU Abulfotuh, F Balcioglu, A Friedman, D Geisz, J Kurtz, S AF Abulfotuh, F Balcioglu, A Friedman, D Geisz, J Kurtz, S BE AlJassim, M Thornton, JP TI Investigation of deep levels in GaInNAs SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID TRAPS AB This paper presents and discusses the first Deep-Level transient spectroscopy (DLTS) data obtained from measurements carried out on both Schottky barriers and homojunction devices of GaInNAs. The effect of N and In doping on the electrical properties of the GaNInAs devices, which results in structural defects and interface states, has been investigated. Moreover, the location and densities of deep levels related to the presence of N, In, and N+In are identified and correlated with the device performance. The data confirmed that the presence of N alone creates a high density of shallow hole traps related to the N atom and structural defects in the device. Doping by In, if present alone, also creates low-density deep traps (related to the In atom and structural defects) and extremely deep interface states. On the other hand, the co-presence of In and N eliminates both the interface states and levels related to structural defects. However, the device still has a high density of the shallow and deep traps that are responsible for the photocurrent loss in the GaNInAs device, together with the possible short diffusion length. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Abulfotuh, F (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 5 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 492 EP 498 PG 7 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900076 ER PT S AU Woods, LM Levi, DH Kaydanov, V Robinson, GY Ahrenkiel, RK AF Woods, LM Levi, DH Kaydanov, V Robinson, GY Ahrenkiel, RK BE AlJassim, M Thornton, JP TI Electrical characterization of etched grain-boundary properties from As-processed px-CdTe-based solar cells SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB An ability to lift off or separate the thin-film polycrystalline CdTe from the CdS, without the use of chemical etches, has enabled direct electrical characterization of the as-processed CdTe near the CdTe/CdS heterointerface. We use this ability to understand how a back-contact, nitric-phosphoric (NP) etch affects the grain boundaries throughout the film. Quantitative determination of the grain-boundary barrier potentials and estimates of doping density near the grain perimeter are determined from theoretical fits to measurements of the current vs. temperature. Estimates of the bulk doping are determined from high-frequency resistivity measurements. Also, a variable doping density within the grains of non-etched material has been determined. These results allow a semi-quantitative grain-boundary band diagram to be drawn that should aid in determining more-accurate two-dimensional models for polycrystalline CdTe solar cells. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Woods, LM (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 15 TC 5 Z9 5 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 499 EP 504 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900077 ER PT S AU Johnston, SW Ahrenkiel, RK AF Johnston, SW Ahrenkiel, RK BE AlJassim, M Thornton, JP TI Measurement of the temperature-dependent recombination lifetimes in photovoltaic materials SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID MINORITY-CARRIER LIFETIME; P-TYPE SILICON; METALLIC IMPURITIES; WAFERS; CRYSTALS AB Lifetime spectroscopy is a valuable tool for the characterization of photovoltaic materials. Measured lifetime values are inherently dependent on the defect and impurity densities present in the material. Injection-level and temperature dependencies of the recombination rate further characterize the material and possibly provide information for the identification of specific impurities. Also, trapping levels may be determined by observing their temperature-dependent thermal emission. Measured examples include surface-passivated, float-zone silicon and high-quality, undoped GaAs. Excess-carrier-decay curves are recorded from 80 to 300 K using a lifetime-measurement technique called ultrahigh frequency photoconductive decay. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Johnston, SW (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 22 TC 1 Z9 1 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 505 EP 510 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900078 ER PT S AU Keyes, BM Geisz, JF Dippo, PC Reedy, R Kramer, C Friedman, DJ Kurtz, SR Olson, JM AF Keyes, BM Geisz, JF Dippo, PC Reedy, R Kramer, C Friedman, DJ Kurtz, SR Olson, JM BE AlJassim, M Thornton, JP TI Optical investigation of GaNAs SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP Conference Proceedings LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB A systematic study of the energy and time-resolved photolumienscence of GaInP/GaNxAs1-x double heterostructures has been performed for 0 less than or equal to x less than or equal to 1.3%. A large temperature-dependent optical-bowing coefficient (about 20-25 eV) is observed and the bandgap variation with temperature is found to depend on the nitrogen content. Finally, the minority-carrier lifetime is not simply related to the nitrogen content. Instead, the recombination rate is proportional to the majority-carrier concentration for x greater than or equal to 0.3% and the carbon concentration for x less than or equal to 0.3%. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM brian_keyes@nrel.gov; patricia_dippo@nrel.gov; bob_reedy@nrel.gov; charlene_kramer@nrel.gov; daniel_friedman@nrel.gov; sarah_kurtz@nrel.gov; jerry_olson@nrel.gov NR 11 TC 21 Z9 21 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 511 EP 516 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900079 ER PT S AU Moutinho, HR Dhere, RG Al-Jassim, MM Mayo, B Levi, DH Kazmerski, LL AF Moutinho, HR Dhere, RG Al-Jassim, MM Mayo, B Levi, DH Kazmerski, LL BE AlJassim, M Thornton, JP TI Induced recrystallization of CdTe thin films deposited by close-spaced sublimation SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID CDCL2 AB We have deposited CdTe thin films by close-spaced sublimation at two different temperature ranges. The films deposited at the lower temperature partially recrystallized after CdCl2 treatment at 350 degrees C and completely recrystallized after the same treatment at 400 degrees C. The films deposited at higher temperature did not recrystallize at these two temperatures. These results confirmed that the mechanisms responsible for changes in physical properties of CdTe films treated with CdCl2 are recrystallization and grain growth, and provided an alternative method to deposit CSS films using lower temperatures. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Moutinho, HR (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 8 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 517 EP 523 PG 7 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900080 ER PT S AU Webb, JD Keane, J Ribelin, R Gedvilas, L Swartzlander, A Ramanathan, K Albin, DS Noufi, R AF Webb, JD Keane, J Ribelin, R Gedvilas, L Swartzlander, A Ramanathan, K Albin, DS Noufi, R BE AlJassim, M Thornton, JP TI Spectroscopic analysis of impurity precipitates in CdS films SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID THIN-FILMS AB Impurities in cadmium sulfide (CdS) films are a concern in the fabrication of copper (indium, gallium) diselenide (CIGS) and cadmium telluride (CdTe) photovoltaic devices, Devices incorporating chemical-bath-deposited (CBD) CdS are comparable in quality to devices incorporating purer CdS films grown using vacuum deposition techniques, despite the higher impurity concentrations typically observed in the CBD CdS films. In this paper, we summarize and review the results of Fourier transform infrared (FTIR), Auger, electron microprobe, and X-photoelectron spectroscopic (XPS) analyses of the impurities in CBD CdS films. We show that these impurities differ as a function of substrate type and film deposition conditions. We also show that some of these impurities exist as 10(2) micron-scale precipitates. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Webb, JD (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 24 TC 0 Z9 0 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 524 EP 530 PG 7 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900081 ER PT S AU Jones, KM Al-Jassim, MM Hasoon, FS Venkatasubramanian, R AF Jones, KM Al-Jassim, MM Hasoon, FS Venkatasubramanian, R BE AlJassim, M Thornton, JP TI The morphology and microstructure of thin-film GaAs on Mo substrates SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID CELL AB The growth of GaAs thin films on Molybdenum foils was investigated in an attempt to find a low-cost substrate for GaAs. The films were grown by metalorganic chemical vapor deposition (MOCVD). The film thickness was in the 2-4 mu m range, while the deposition temperature was in the 650 degrees-825 degrees C range. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to investigate the film morphology and microstructure, respectively. The film morphology in general, and the grain size in particular, were found to be strongly dependent on the growth temperature. However, the defect structure observed in these films was relatively insensitive to the growth conditions. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Jones, KM (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 5 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 531 EP 536 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900082 ER PT S AU Reedy, RC Mason, AR Nelson, BP Xu, Y AF Reedy, RC Mason, AR Nelson, BP Xu, Y BE AlJassim, M Thornton, JP TI SIMS characterization of amorphous silicon germanium alloys grown by hot-wire deposition SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB In this paper, we present methods for the quantitative secondary ion mass spectrometry (SIMS) characterization of amorphous SiGe:H alloy materials. A set of samples was grown with germanium content ranging from 5% to 77% and was subsequently analyzed by electron probe X-ray microanalysis (EPMA) and nuclear reaction analysis (NRA). Calibration of the SIMS quantification was performed with respect to EPMA data for germanium and NRA data for hydrogen. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Reedy, RC (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 3 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 537 EP 541 PG 5 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900083 ER PT S AU Matson, RJ Granata, JE Asher, SE Young, MR AF Matson, RJ Granata, JE Asher, SE Young, MR BE AlJassim, M Thornton, JP TI Effects of substrate and Na concentration on device properties, junction formation, and film microstructure in CuInSe2 PV devices SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB Different concentrations of Na were systematically introduced into CuInSe2 (CIS) photovoltaic solar cell. absorber material on different substrates (SLG, SiO2/SLG, 7059, alumina) to: 1) determine the resultant effects on device properties, junction formation, and material microstructure; and 2) determine the optimal range of Na concentrations in the CIS films per specific substrate. In general, finished devices show improved V-oc, J(sc,) and device efficiency, improved charge-collection efficiency and, possibly, increased grain size as a result of the coevaportion of 1 to 100 mg of Na2Se during film deposition. However, a dramatic devolution set in with the addition of 235 mg of Na2Se, and ail the aforementioned parameters were either at, or worse than, their pre-Na-addition levels, Meanwhile, although the device microstructure improves with Na addition and, more importantly, the junction las characterized by electron-beam-induced current) has become much more uniform and closer to the heteroface, all that reverses with the "Na overdose." C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Matson, RJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 5 TC 6 Z9 6 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 542 EP 549 PG 8 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900084 ER PT S AU Rummel, S Emery, K Field, H Moriarty, T Anderberg, A Dunlavy, D Ottoson, L AF Rummel, S Emery, K Field, H Moriarty, T Anderberg, A Dunlavy, D Ottoson, L BE AlJassim, M Thornton, JP TI PV cell and module performance measurement capabilities at NREL SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID EFFICIENCY AB The Photovoltaic (PV) Cell and Module Performance Characterization team at NREL supports the entire photovoltaic community by providing: secondary calibrations of photovoltaic cells and modules; efficiency measurements with respect to a given set of standard reporting conditions; verification of contract efficiency milestones; and current versus voltage (I-V) measurements under various conditions of temperature, spectral irradiance, and total irradiance. Support is also provided to in-house programs in device fabrication, module stability, module reliability, PV systems evaluations, and alternative rating methods by performing baseline testing, specialized measurements and other assistance when required. The I-V and spectral responsivity equipment used to accomplish these tasks are described in this paper. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Rummel, S (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 553 EP 558 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900085 ER PT S AU Pern, FJ Glick, SH AF Pern, FJ Glick, SH BE AlJassim, M Thornton, JP TI Accelerated exposure tests of encapsulated Si solar cells and encapsulation materials SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB We have conducted a series of accelerated exposure test (AET) studies for various crystalline-Si (c-Si) and amorphous-Si (a-Si) cell samples that were encapsulated with different superstrates, pottants, and substrates. Nonuniform browning patterns of ethylene vinyl acetate (EVA) pottants were observed for glass/EVA/glass-encapsulated c-Si cell samples under solar simulator exposures at elevated temperatures. The polymer/polymer-configured laminates with Tedlar or Tefzel did not discolor because of photobleaching reactions, but yellowed with polyester or nylon top films. Delamination was observed for the polyester/EVA layers on a-Si minimodules and for a polyolefin-based thermoplastic pottant at high temperatures. For all tested c-Si cell samples, irregular changes in the current-voltage parameters were observed that could not be accounted for simply by the transmittance changes of the superstrate/pottant layers. Silicone-type adhesives used under UV-transmitting polymer top films were observed to cause greater cell current/efficiency loss than EVA or polyethylene pottants. C1 Natl Renewable Energy Lab, Natl Ctr Photovolta, Div Engn & Reliabil, Golden, CO 80401 USA. RP Pern, FJ (reprint author), Natl Renewable Energy Lab, Natl Ctr Photovolta, Div Engn & Reliabil, Golden, CO 80401 USA. NR 5 TC 1 Z9 1 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 559 EP 564 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900086 ER PT S AU King, DL Quintana, MA Kratochvil, JA Ellibee, DE Hansen, BR AF King, DL Quintana, MA Kratochvil, JA Ellibee, DE Hansen, BR BE AlJassim, M Thornton, JP TI Photovoltaic module performance and durability following long-term field exposure SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID PV MODULE; ENCAPSULATION; POTTANT AB This paper summarizes test procedures, results, and implications of in-depth investigations of the performance and durability characteristics of commercial photovoltaic modules after long-term field exposure. New diagnostic test procedures for module reliability research are discussed and illustrated. A collaborative effort with U.S. module manufacturers aimed at achieving 30-year module lifetimes is also described. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP King, DL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 10 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 565 EP 572 PG 8 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900087 ER PT S AU Osterwald, CR Basso, TS del Cueto, JA McMahon, TJ Pruett, J Trudell, D AF Osterwald, CR Basso, TS del Cueto, JA McMahon, TJ Pruett, J Trudell, D BE AlJassim, M Thornton, JP TI Accelerated and environmental module stress testing at NREL SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB This paper presents an overview of the Module Testing and Technology Validation task at the National Renewable Energy Laboratory. The extensive module testing capabilities at the Outdoor Test Facility are outlined, emphasizing the test facilities, equipment, and analytical services available. Highlights and results of several recent testing efforts are then presented, followed by a list of the external programs supported by the task. The paper concludes with a brief description of the new testing programs that are planned for the near future. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Osterwald, CR (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 573 EP 577 PG 5 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900088 ER PT S AU Bonn, RH Ginn, J Hund, T Gonzalez, S Ralph, M Strommen, R AF Bonn, RH Ginn, J Hund, T Gonzalez, S Ralph, M Strommen, R BE AlJassim, M Thornton, JP TI Sandia national laboratories photovoltaic balance of systems program SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB The Sandia National Laboratories photovoltaic balance of system (BOS) program is sponsored by the Department of Energy to increase the reliability and lower the cast of BOS components. Efforts for FY1998 are discussed. Principal efforts include a quality program for inverter manufacturers, a grid-tied anti-islanding program, development of a hybrid inverter, hardware benchmarking program, and a battery evaluation program. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Bonn, RH (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 578 EP 583 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900089 ER PT S AU DeBlasio, R AF DeBlasio, R BE AlJassim, M Thornton, JP TI PV system testing and standards SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB The U.S. Department of Energy (DOE) PV Program System Performance and Engineering Project is being conducted by The National Renewable Energy Laboratory (NREL), Sandia National Laboratories (SNL), Southwest Technology Development Institute (SWTDI), and Florida Solar Energy Center (FSEC), It provides PV system, subsystem, and component-level technology-performance characterization testing; test-method development and validation; national and international consensus standards and codes development test-facility product certification, and laboratory-accreditation program implementation; and information exchange and technical assistance to the PV community. Emphasis is placed on reducing technical and infrastructural barriers to system acceptance, reducing life-cycle cast of systems, providing systems-engineering best practices and guidelines, and leading the national effort in performance and reliability testing and consensus standards, codes, and certification program development and implementation - thereby ensuring that PV systems meet customers' needs and expectations. A summary of project activities, accomplishments, and future plans is provided and highlighted by an overview of PV system test-procedure and standards development. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP DeBlasio, R (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 2 TC 0 Z9 0 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 584 EP 589 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900090 ER PT S AU Pern, FJ Glick, SH Czanderna, AW AF Pern, FJ Glick, SH Czanderna, AW BE AlJassim, M Thornton, JP TI Review of the photothermal stability of EVA pottants: Effects of formulation on the discoloration rate and mitigation methods SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID PV MODULES AB Results from extensive studies of the commercial ethylene vinyl acetate (EVA) formulations show that the UV absorber and curing-generated UV-excitable, alpha,beta-unsaturated carbonyl chromophores facilitate the EVA discoloration, which is further enhanced by curing-generated acetic acid and probably residual peroxide curing agent also. Formation and concentration of the W-e?;citable chromophores are substantially promoted by the antioxidant Naugard P. The discoloration rate is greater under higher UV light intensity and temperatures. Heating in the dark at elevated temperatures (e.g., 85 degrees C) in the air for similar to 200 days only results in light yellowing. The discoloration reactions compete with photobleaching reactions, which destroy curing-generated chromophores and result in non-discoloring of EVA. By using better performance stabilizers to minimize the curing-generated W-excitable chromophores, a new fast curing agent, and no UV absorber, the NREL-developed EVA formulations show a superior photothermal stability against browning to the commercial counterparts. Alternatively, the discoloration rate of the commercial EVA pottants can be considerably reduced by using UV-filtering glass superstrates that largely inhibit the W-induced photooxidation reactions, or completely eliminated by using air-permeable polymer superstrate films that enable photobleaching reactions. C1 Natl Renewable Energy Lab, Natl Ctr Photovolta, Div Engn & Reliabil, Golden, CO 80401 USA. RP Pern, FJ (reprint author), Natl Renewable Energy Lab, Natl Ctr Photovolta, Div Engn & Reliabil, Golden, CO 80401 USA. NR 14 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 599 EP 604 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900092 ER PT S AU McNutt, P AF McNutt, P BE AlJassim, M Thornton, JP TI Comparison of time required to charge a battery in a stand-alone photovoltaic system using different charge-controller types SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB An experiment was conducted at the National Renewable Energy Laboratory (NREL) comparing the time required to charge a fully discharged valve-regulated lead-acid battery in a photovoltaic (PV) system using on/off-shunt and pulse-width-modulated (PWM) charge controllers. In one system configuration, an on/off-shunt charge controller was only able to charge the battery to 61% of its rated capacity after 16 days. In a subsequent test, a different on/off-shunt controller in a different PV system configuration readily charged its battery to 100% rated capacity in less than 6 days. It charged its battery as quickly as a couple different PWM charge controllers did in identical systems in a side-by-side comparison. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP McNutt, P (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 3 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 605 EP 610 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900093 ER PT S AU Kroposki, B Hansen, R AF Kroposki, B Hansen, R BE AlJassim, M Thornton, JP TI Improvements in the performance of a 1-kW copper indium diselenide array SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB A new copper indium diselenide (CIS) array installed at the National Renewable Energy Laboratory (NREL) shows a marked improvement over the previous generation in terms of power output and efficiency. The new array is part of NREL's technical validation, started in 1992, of small (1-2 kW) thin-film systems. The purpose of this testing is to evaluate the performance and reliability of thin-film modules in a system application. The first array had a rated power at 969 W and an average efficiency of 7.2% at standard test conditions(STC). The second array is rated at 1008 W, and the average efficiency is 9.0% at STC. The data in this paper shows that the new CIS modules have improved by about 37% in relative efficiency under actual operating conditions. The new array's results demonstrate that Siemens Solar Industries has made significant improvements in the performance of their large-area CIS modules. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kroposki, B (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 2 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 611 EP 616 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900094 ER PT S AU del Cueto, JA AF del Cueto, JA BE AlJassim, M Thornton, JP TI Guide to the field performance of c-Si PV modules SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB In-situ performance data taken from six crystalline silicon (c-Si) modules deployed in the field are analyzed. These data are summarized in terms of the temperature coefficients of the modules' current-voltage (I-V) parameters, dissected into four representative illumination levels (125, 250, 500 and 1000 W/m(2) irradiance). The average efficiency taken at 1000 W/m(2) irradiance and referenced to 25 degrees C span a range of values from 10.5% to 13.2%, for the six modules. Yet, the behavior of the temperature coefficients of the I-V curves exhibit similar functional dependence against irradiance for each of the I-V parameters. The data show the temperature coefficients vary substantially across the range of illumination levels examined. Hence, if extrapolation of module performance in the field is made from a single set of coefficients measured at one illumination level, it will likely result in inaccurate prediction of that performance. Furthermore, the data show that when measured under natural lighting, there is a fair amount of dispersion in coefficients and performance at the lower (about 250 W/m(2) or less) irradiance levels. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP del Cueto, JA (reprint author), Natl Renewable Energy Lab, M-S 3411,1617 Cole Blvd, Golden, CO 80401 USA. NR 6 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 617 EP 622 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900095 ER PT S AU Cannon, TW AF Cannon, TW BE AlJassim, M Thornton, JP TI Spectral measurements of pulse solar simulators SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB Spectral measurements of pulse solar simulators are used to quantify the wavelength-dependant characteristics of the light. Because every PV device has a unique spectral response, it is important to know the spectral irradiance and to periodically monitor the spectra for changes. Measurements are made at the National Renewable Energy Laboratory (NREL) using several different techniques including the NREL-developed Pulse Analysis Spectroradiometer System (PASS). C1 Natl Renewable Energy Lab, Ctr Renewable Energy Resources, Golden, CO 80401 USA. RP Cannon, TW (reprint author), Natl Renewable Energy Lab, Ctr Renewable Energy Resources, 1617 Cole Blvd,MS 3411, Golden, CO 80401 USA. NR 6 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 623 EP 628 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900096 ER PT S AU Field, H AF Field, H BE AlJassim, M Thornton, JP TI UV-VIS-IR spectral responsivity measurement system for solar cells SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB NREL's PV Cell and Module Performance Characterization group has built a new spectral responsivity measurement system for solar cells. It uses a xenon are lamp source, a single, grating monochrometer, and a fiber-optic bundle to couple the monochromatic light to the test device. The system has a spectral bandwidth of 2 nm, minimum spot diameter of 1.6 mm, a spectral range of 280-1330 nm, and uncertainty better than +/-3% over most of this range. It is capable of incorporating light bias with intensities exceeding one sun. This paper discusses the system's features, capabilities, calibration, and measurement uncertainties. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Field, H (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 3 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 629 EP 635 PG 7 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900097 ER PT S AU Pitts, JR King, DE Bingham, C Czanderna, AW AF Pitts, JR King, DE Bingham, C Czanderna, AW BE AlJassim, M Thornton, JP TI Ultra accelerated testing of PV module components SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta ID ETHYLENE AB Using concentrated natural sunlight at the NREL High Flux Solar Furnace, we have exposed several materials to acceleration factors of up to 400 times the normal outdoor UV exposure dose. This accelerated rate allows the exposure of materials such that a year of outdoor exposure can be simulated in about 5 hours. We have studied the solarization of cerium containing glass, the degradation of ethylene vinyl acetate laminated between borosilicate glass, and the yellowing of standard polystyrene test coupons. The first two candidates are of interest to the photovoltaics (PV) program, and the last candidate material is a widely used dosimeter for ultra violet (UV) exposure in accelerated weathering chambers. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Pitts, JR (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 636 EP 642 PG 7 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900098 ER PT S AU Basso, TS AF Basso, TS BE AlJassim, M Thornton, JP TI The NREL outdoor accelerated-weathering tracking system and photovoltaic module exposure results SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB This paper describes the Outdoor Accelerated-weathering Tracking System (OATS) and interim results for the first OATS study on photovoltaic (PV) modules. With two test planes measuring 1.52 x 1.83 m, OATS provides a unique solar-concentrating exposure capability. Test sample temperatures are moderated by air blowers. Water spray capability exists for wetting samples. The OATS two-axis tracker points to the sun using software calculations. Non-imaging aluminum reflectors give a nominal clear-sky optical concentration ratio of three. Field-qualification measurements in the test plane under reflector conditions showed its relative irradiance non-uniformity was +/- 15% for a clear-sky summer day with +/- 75 mm as the smallest distance for that non-uniformity. Exposure studies began in November 1997 on seven pairs of commercially available ribbon silicon, crystalline silicon and amorphous silicon PV modules kept at constant resistive load. The modules were periodically removed from OATS for visual inspection and solar simulator performance measurements. There were no module failures. This PV module study is ongoing and later results will be compared to other testing techniques. Through July 1998, the modules under reflector conditions received 392 MJ/m(2) of total ultraviolet (TUV) exposure. That was 2.07 times the TUV exposure compared to a south-facing fixed array tilted 40 degrees up from horizontal at NREL. Similarly, the modules in the test plane under the covered reflectors received 1.04 times the fixed array TUV exposure. For the test plane under the covered reflectors there was a loss of 13% TUV exposure attributed to the reflectors blocking some of the diffuse-sky UV light. Also through July 1998, the OATS sunlight availability measured 95% compared to the cumulative global normal exposure at the NREL Solar Radiation Research Laboratory (SRRL). The OATS sunlight availability losses included downtime when the PV modules were removed, and when there were OATS tracking problems, maintenance, and repair. For December 1997 through July 1998, the SRRL cumulative exposure was 99% compared to the respective monthly averages from years 1961 through 1990 at Boulder, Colorado. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Basso, TS (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 6 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 643 EP 648 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900099 ER PT S AU Myers, DR AF Myers, DR BE AlJassim, M Thornton, JP TI Module energy rating candidate reference days: Criteria and selection process SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB Presently the performance of flat-plate photovoltaic (PV) modules is based upon module power, open circuit voltage, short-circuit current, or peak power voltage and current with respect to fixed environmental conditions such as Standard Reporting Conditions, (SRC) or nominal operating cell temperature. These reporting conditions represent ideal conditions under which PV module performance (e.g., between manufacturers or technologies) may be compared They result in overly optimistic expectations of performance by PV industry customers. A recommended practice for PV module energy-rating methodologies to relate PV module performance to real world conditions is under development The methodologies will provide system designers and PV customers with an energy rating representative of real world conditions. The rating methodology reports energy production under 5 selected types of days representative of possible operational environments. The development and application of qualitative and quantitative criteria for identifying and selecting these representative days from the 30-year U.S. National Solar Radiation Data Base is described. C1 Natl Renewable Energy Lab, Ctr Renewable Energy Resources, Golden, CO 80401 USA. RP Myers, DR (reprint author), Natl Renewable Energy Lab, Ctr Renewable Energy Resources, 1617 Cole Blvd,MS 3411, Golden, CO 80401 USA. NR 11 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 649 EP 654 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900100 ER PT S AU Meier, A Glick, SH Pern, FJ AF Meier, A Glick, SH Pern, FJ BE AlJassim, M Thornton, JP TI Impedance spectroscopy as a non-invasive analytical method for monitoring solar cell degradation SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB Stationary impedance spectroscopic investigations in the dark have been used to monitor the degradation of silicon photovoltaic cells in long-term exposure-testing experiments. For approximately six months, a number of silicon cells were exposed to environmental stress factors such as elevated temperatures and UV light while the stationary current and impedance spectra (1 Hz to 100 kHz) were recorded under reverse and forward bias. The careful analysis of the current and impedance data according to an appropriate model reveals slight changes in the electrical characteristics of the cells. These alterations are attributed to changes in the trap density at the n(+)/p junction. C1 Natl Renewable Energy Lab, Div Basic Sci, Golden, CO 80401 USA. RP Meier, A (reprint author), Natl Renewable Energy Lab, Div Basic Sci, 1617 Cole Blvd, Golden, CO 80401 USA. NR 2 TC 1 Z9 1 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 661 EP 666 PG 6 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900102 ER PT S AU Mitchell, RL Symko-Davies, M Thomas, HP Witt, CE AF Mitchell, RL Symko-Davies, M Thomas, HP Witt, CE BE AlJassim, M Thornton, JP TI PVMaT 1998 overview SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB The Photovoltaic Manufacturing Technology (PVMaT) Project is a government/industry research and development (R&D) partnership between the U.S. federal government (through the U.S. Department of Energy [DOE]) and members of the U.S. PV industry. The goals of PVMaT are to assist the U.S. PV industry improve module manufacturing processes and equipment; accelerate manufacturing cost reductions for PV modules, balance-of-systems components, and integrated systems; increase commercial product performance and reliability; and enhance investment opportunities for substantial scale-ups of U.S.-based PV manufacturing plant capacities. The approach for PVMaT has been to cost-share the R&D risk as industry explores new manufacturing options and ideas far improved PV modules and components, advances system and product integration, and develops new system designs. These activities will lead to overall reduced system life-cycle costs for reliable PV end-products. The 1994 PVMaT Product-Driven BOS and Systems activities, as well as Product-Driven Module Manufacturing R&D activities, are just being completed. Fourteen new subcontracts have just been awarded in the areas of PV System and Component Technology and Module Manufacturing Technology. Government funding, subcontractor cost-sharing, and a comparison of the relative efforts by PV technology throughout the PVMaT project are also discussed. C1 Natl Ctr Photovolta, Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Mitchell, RL (reprint author), Natl Ctr Photovolta, Natl Renewable Energy Lab, MS-3221,1617 Cole Blvd, Golden, CO 80401 USA. NR 6 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 711 EP 715 PG 5 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900109 ER PT S AU Herig, C AF Herig, C BE AlJassim, M Thornton, JP TI Update on the million solar roofs initiative SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB The Million Solar Roofs Initiative, announced by the President in June of 1997, spans a period of twelve years and intends to increase domestic deployment of solar technologies. This paper presents an overview of the development of the initiative and significant activities to date. C1 Natl Ctr Photovolta, Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Herig, C (reprint author), Natl Ctr Photovolta, Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 1 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 761 EP 768 PG 8 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900118 ER PT S AU Hayter, SJ AF Hayter, SJ BE AlJassim, M Thornton, JP TI Photovoltaics for buildings: Key issues in pursuit of market readiness SO NCPV PHOTOVOLTAICS PROGRAM REVIEW: PROCEEDINGS OF THE 15TH CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th Program Review Meeting of the National-Center-for-Photovoltaics CY SEP 09-11, 1998 CL DENVER, CO SP Natl Ctr Photovolta AB The photovoltaic (PV) industry is rapidly beginning to recognize the market potential of the buildings sector. New PV-for-buildings products have recently become commercially available, and numerous products that are under development will be introduced within the nest 5 years. To ensure that these new products will be adopted and used in common building practices, the PV industry should recognize and address important buildings industry issues. These issues include building codes and standards, after-market servicing, education, and warranties and insurance policies. Photovoltaic systems are also still very expensive. The simplest method for increasing their value for a building is to decrease the building's electrical loads through energy efficiency and conservation. Meeting these goals can only be accomplished through partnerships with the U.S. Department of Energy (DOE), private industry, and public institutions. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Hayter, SJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 1 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 1-56396-836-3 J9 AIP CONF PROC PY 1999 VL 462 BP 769 EP 775 PG 7 WC Energy & Fuels; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Condensed Matter SC Energy & Fuels; Materials Science; Optics; Physics GA BM77U UT WOS:000079745900119 ER PT J AU Harper, RM Richard, CA Rector, DM AF Harper, RM Richard, CA Rector, DM TI Physiological and ventral medullary surface activity during hypovolemia SO NEUROSCIENCE LA English DT Article DE shock; sudden infant death syndrome; heart rate; blood pressure; optical imaging; autonomic nervous system ID FREELY BEHAVING ANIMALS; INFANT-DEATH-SYNDROME; ARCUATE NUCLEUS; STIMULATION; RESPONSES; PRESSURE; CHALLENGES; SIGNALS; CORTEX; SLICES AB The objective was to determine ventral medullary surface responses to blood loss sufficient to induce shock. We examined changes in scattered light from rostral and intermediate areas of the ventral medullary surface in four intact, drug-free cars during acute hypovolemia. Scattered light images, collected during 660 and 560 nm illumination to measure cellular activity and hemodynamic aspects, respectively, were digitized at 50 frames/s during baseline, and during withdrawal of 20-30% blood volume. Hypovolemia elicited a profound hypotension and eventual bradycardia. In all cats, a modest increase in ventral medullary surface reflectance (activity decline) accompanied initial blood loss; as hypovolemia continued, and blood pressure declined, reflectance switched to a decline (activity increase), with the lowest reflectance occurring at maximal blood loss. Hypovolemia elicited multiple transient physiologic behaviors, including tachycardia, tachypnea, intermittent isolated and sustained bursts of enhanced inspiratory efforts, and extensor activation of the somatic musculature. The phasic physiological behaviors during hypovolemia were accompanied by partial recovery of medullary surface reflectance and blood pressure towards baseline values; however, reflectance continued to decrease as blood pressure progressively fell after these recovery efforts. Patterns of reflectance were not uniform over areas examined; isolated regions of enhanced or diminished reflectance appeared upon the overall images, Optical signals indicating hemodynamic changes followed the neural activity patterns, but not precisely. Regions within the ventral surface are responsive to hypovolemia, and to transient behaviors associated with momentary restoration of blood pressure; these ventral surface areas may assume essential roles in the systemic response to hypovolemic induced shock. (C) 1999 IBRO. Published by Elsevier Science Ltd. C1 Univ Calif Los Angeles, Dept Neurobiol, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Brain Res Inst, Los Angeles, CA 90095 USA. Univ Calif Irvine, Irvine Med Ctr, Dept Neurol, Orange, CA 92868 USA. Univ Calif Los Alamos Natl Lab, Biophys Grp, Los Alamos, NM 87545 USA. RP Harper, RM (reprint author), Univ Calif Los Angeles, Dept Neurobiol, Los Angeles, CA 90095 USA. FU NICHD NIH HHS [HD-22506] NR 33 TC 18 Z9 19 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0306-4522 J9 NEUROSCIENCE JI Neuroscience PY 1999 VL 94 IS 2 BP 579 EP 586 DI 10.1016/S0306-4522(99)00347-4 PG 8 WC Neurosciences SC Neurosciences & Neurology GA 245YE UT WOS:000083135600021 PM 10579218 ER PT B AU White, DH AF White, DH CA LSND Collaboration BE Suzuki, Y Totsuka, Y TI Neutrino oscillation results from LSND SO NEUTRINO PHYSICS AND ASTROP HYSICS LA English DT Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan ID SEARCH; ISIS AB The LSND experiment at Los Alamos has conducted a search for <(nu)over bar>(mu) --> <(nu)over bar>(e) oscillations using <(nu)over bar>(mu) from mu(+) decay at rest. The <(nu)over bar>(e) are detected via the reaction <(nu)over bar>(e) p --> e(+) n, correlated with the 2.2 MeV gamma from np --> d gamma. The use of tight cuts to identify e(+) events with correlated gamma rays yielded 22 events with e(+) energy between 36 and 60 MeV and only 4.6 +/- 0.6 background events. The probability that this excess is due entirely to a statistical fluctuation is 4.1 x 10(-8). A chi(2) fit to the entire ef sample results in a total excess of 51.8(-16.9)(+18.7) +/- 8.0 events with e(+) energy between 20 and 60 MeV. If attributed to <(nu)over bar>(mu) --> <(nu)over bar>(e) oscillations, this corresponds to an oscillation probability (averaged over the experimental energy and spatial acceptance) of 0.31 +/- 0.12 +/- 0.05. C1 Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. RP White, DH (reprint author), Univ Calif Los Alamos Natl Lab, Div Phys, Mail Stop H846, Los Alamos, NM 87545 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-444-50289-0 PY 1999 BP 207 EP 211 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN70F UT WOS:000082637800029 ER PT B AU Spentzouris, P AF Spentzouris, P BE Suzuki, Y Totsuka, Y TI Neutrino physics with a muon collider SO NEUTRINO PHYSICS AND ASTROP HYSICS LA English DT Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan ID OSCILLATIONS; SEARCH AB In the last few years, the idea of a muon accelerator complex has been actively pursued as an option for the next generation lepton collider. The very intense muon source (similar to 10(21) / per year) required for the collider, could provide very intense neutrino beams from muon decay in flight. The neutrino sources could either be the straight sections of the accelerator and the collider ring or a dedicated muon storage ring. In this note I discuss the physics potential of such neutrino sources for neutrino oscillations and Deep Inelastic Scattering measurements. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Spentzouris, P (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 26 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-444-50289-0 PY 1999 BP 276 EP 284 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN70F UT WOS:000082637800038 ER PT B AU Sadoulet, B AF Sadoulet, B BE Suzuki, Y Totsuka, Y TI Direct searches for dark matter SO NEUTRINO PHYSICS AND ASTROP HYSICS LA English DT Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan ID COLD PLUS HOT; DOUBLE-BETA; COSMOLOGICAL PARAMETERS; CP INVARIANCE; GRAN-SASSO; LIMITS; UNIVERSE; OSCILLATIONS; CANDIDATES; DETECTOR AB After briefly recalling the evidence which suggests that the dark matter pervading the universe is nonbaryonic, we review the present searches for the best motivated particle candidates: axions, light neutrinos and Weakly Interacting Massive Particles (WIMPs). C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Particle Astrophys, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Particle Astrophys, Berkeley, CA 94720 USA. NR 85 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-444-50289-0 PY 1999 BP 389 EP 397 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN70F UT WOS:000082637800052 ER PT B AU Dalhed, HE Wilson, JR Mayle, RW AF Dalhed, HE Wilson, JR Mayle, RW BE Suzuki, Y Totsuka, Y TI Supernova neutrinos: Review SO NEUTRINO PHYSICS AND ASTROP HYSICS LA English DT Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan AB This review discusses the role of neutrinos in the dynamics of supernovae. Neutrinos not only provide an essential probe into the core collapse mechanism, but also probably play an active role in the explosion mechanism. The time history of the neutrino fluences and their spectral shapes are affected by such physics as the nuclear equation of state and convection modeling. In turn, neutrinos play an active role in depositing energy in the region behind the outgoing shock wave and in the potential formation of heavy nuclei via r-process nucleosynthesis. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Dalhed, HE (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave,Mail Stop L-015, Livermore, CA 94550 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-444-50289-0 PY 1999 BP 429 EP 434 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN70F UT WOS:000082637800056 ER PT S AU Daemen, LL Seeger, PA Thelliez, TG Hjelm, RP AF Daemen, LL Seeger, PA Thelliez, TG Hjelm, RP BE Johnson, MR Kearley, GJ Buttner, HG TI A Monte Carlo tool for simulations of neutron scattering instruments SO NEUTRONS AND NUMERICAL METHODS-N(2)M SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT N(2)M Workshop on Neutrons and Numerical Methods CY DEC, 1998 CL GRENOBLE, FRANCE SP Amer Inst Phys, Inst Laue Langevin, Molec Simulat Inc AB A brief description of the Neutron Instrument Simulation Package (NISP) is given, together with an example of its use to calculate the resolution function of an inelastic spectrometer. C1 Univ Calif Los Alamos Natl Lab, Neutron Scattering Ctr, Los Alamos, NM 87545 USA. RP Daemen, LL (reprint author), Univ Calif Los Alamos Natl Lab, Neutron Scattering Ctr, POB 1663, Los Alamos, NM 87545 USA. RI Lujan Center, LANL/G-4896-2012 NR 3 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-838-X J9 AIP CONF PROC PY 1999 VL 479 BP 41 EP 46 DI 10.1063/1.59486 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical; Physics, Mathematical SC Chemistry; Physics GA BN28L UT WOS:000081423400006 ER PT S AU Pratt, LR Garde, S Hummer, G AF Pratt, LR Garde, S Hummer, G BE Caccamo, C Hansen, JP Stell, G TI Theories of hydrophobic effects and the description of free volume in complex liquids SO NEW APPROACHES TO PROBLEMS IN LIQUID STATE THEORY: INHOMOGENEITIES AND PHASE SEPARATION IN SIMPLE, COMPLEX AND QUANTUM FLUIDS SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT Nato Advanced Study Institute on New Approaches to Old and New Problems in Liquid State Theory - Inhomogeneities and Phase Separation in Simple, Complex an Quantum fluids CY JUL 07-17, 1998 CL MESSINA, ITALY SP NATO-ASI, Sci Affairs Div Bruxelles, Univ Messina ID SOLVATION FREE-ENERGIES; HARD-CORE MIXTURES; SIZE DEPENDENCE; STATISTICAL-MECHANICS; PHASE-TRANSITIONS; MOLECULAR LIQUIDS; NONPOLAR SOLUTES; CAVITY FORMATION; ENTROPY; WATER AB Recent progress on molecular theories of hydration of nonpolar solutes in aqueous solution has led to new ways of thinking about the old issue of free, or "available", volume in liquids. This article surveys the principal new results with particular attention to general issues of packing in liquids. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Pratt, LR (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 76 TC 17 Z9 17 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-5670-5 J9 NATO ADV SCI I C-MAT PY 1999 VL 529 BP 407 EP 420 PG 14 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Fluids & Plasmas; Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter SC Thermodynamics; Chemistry; Mechanics; Physics GA BN11B UT WOS:000080737600024 ER PT S AU Brodsky, SJ AF Brodsky, SJ BE Ji, CR MIN, DP TI QCD technology: Light-cone quantization and commensurate scale relations SO NEW DIRECTIONS IN QUANTUM CHROMODYNAMICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 12th Nuclear Physics Summer School and Symposium/11th International Light Cone Workshop CY JUN 21-25, 1999 CL KYUNGJU, SOUTH KOREA SP Seoul Natl Univ, Ctr Theoret Phys, Daewoo Fdn, Korea Sci & Engn Fdn, Deutsch Forsch Gemeinschaft ID LARGE-MOMENTUM-TRANSFER; PERTURBATIVE QUANTUM CHROMODYNAMICS; TWIST PARTON DISTRIBUTIONS; VIRTUAL COMPTON-SCATTERING; TRANSITION FORM-FACTOR; ONE TIME DIMENSION; DRELL-YAN PROCESS; EXCLUSIVE PROCESSES; GAUGE-THEORIES; FIELD-THEORY AB I discuss several theoretical tools which are useful for analyzing perturbative and non-perturbative problems in quantum chromodynamics, including (a) the light-cone Fock expansion, (b) the effective charge alpha(V), (c) conformal symmetry, and (d) commensurate scale relations. Light-cone Fock-state wavefunctions encode the properties of a hadron in terms of its fundamental quark and gluon degrees of freedom. Given the proton's light-cone wavefunctions, one can compute not only the quark and gluon distributions measured in deep inelastic lepton-proton scattering, but also the multi-part;on correlations which control the distribution of particles in the proton fragmentation region and dynamical higher twist effects. Light-cone wavefunctions also provide a systematic framework for evaluating exclusive hadronic matrix elements, including timelike heavy hadron decay amplitudes and form factors. The alpha(V) coupling, defined from the QCD heavy quark potential, provides a physical expansion parameter for perturbative QCD with an analytic dependence on the fermion masses which is now known to two-loop order. Conformal symmetry provides a template for QCD predictions, including relations between observables which are present even in a theory which is not scale invariant. Commensurate scale relations are perturbative QCD predictions based on conformal symmetry relating observable to observable at fixed relative scale. Such relations have no renormalization scale or scheme ambiguity. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Brodsky, SJ (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 175 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-908-4 J9 AIP CONF PROC PY 1999 VL 494 BP 3 EP 44 PG 42 WC Physics, Particles & Fields SC Physics GA BP14H UT WOS:000084221500001 ER PT S AU Csaki, C Terning, J AF Csaki, C Terning, J BE Ji, CR MIN, DP TI Glueball mass spectrum from supergravity SO NEW DIRECTIONS IN QUANTUM CHROMODYNAMICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 12th Nuclear Physics Summer School and Symposium/11th International Light Cone Workshop CY JUN 21-25, 1999 CL KYUNGJU, SOUTH KOREA SP Seoul Natl Univ, Ctr Theoret Phys, Daewoo Fdn, Korea Sci & Engn Fdn, Deutsch Forsch Gemeinschaft AB We review the calculation of the spectrum of glueball masses in nonsupersymmetric Yang-Mills theory using the conjectured duality between supergravity and large N gauge theories. The glueball masses are obtained by solving the supergravity wave equations in a black hole geometry. The glueball masses found this way are in unexpected agreement with the available lattice data. We also show how to use a modified version of the duality based on rotating branes to calculate the glueball mass spectrum with some of the Kaluza-Klein states of the supergravity theory decoupled from the spectrum. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Csaki, C (reprint author), Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. NR 19 TC 6 Z9 6 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 1-56396-908-4 J9 AIP CONF PROC PY 1999 VL 494 BP 321 EP 328 PG 8 WC Physics, Particles & Fields SC Physics GA BP14H UT WOS:000084221500021 ER PT S AU Garvey, GT AF Garvey, GT BE Ji, CR MIN, DP TI Measurement and origin of the (u)over-bar,(d)over-bar asymmetry in the nucleon sea SO NEW DIRECTIONS IN QUANTUM CHROMODYNAMICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 12th Nuclear Physics Summer School and Symposium/11th International Light Cone Workshop CY JUN 21-25, 1999 CL KYUNGJU, SOUTH KOREA SP Seoul Natl Univ, Ctr Theoret Phys, Daewoo Fdn, Korea Sci & Engn Fdn, Deutsch Forsch Gemeinschaft ID LIGHT-QUARK SEA; DRELL-YAN PROCESS; FLAVOR ASYMMETRY; PARTON DISTRIBUTIONS; SYMMETRY-BREAKING; GOTTFRIED SUM; SPIN; MODEL; SCATTERING; PROTON 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, MS H846, Los Alamos, NM 87545 USA. NR 37 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 1-56396-908-4 J9 AIP CONF PROC PY 1999 VL 494 BP 477 EP 486 PG 10 WC Physics, Particles & Fields SC Physics GA BP14H UT WOS:000084221500040 ER PT S AU Peng, JC AF Peng, JC BE Ji, CR MIN, DP TI Dileptons from p-nucleus collisions SO NEW DIRECTIONS IN QUANTUM CHROMODYNAMICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 12th Nuclear Physics Summer School and Symposium/11th International Light Cone Workshop CY JUN 21-25, 1999 CL KYUNGJU, SOUTH KOREA SP Seoul Natl Univ, Ctr Theoret Phys, Daewoo Fdn, Korea Sci & Engn Fdn, Deutsch Forsch Gemeinschaft ID DRELL-YAN PROCESS; RADIATIVE ENERGY-LOSS; DEEP-INELASTIC-SCATTERING; LEPTON PAIR PRODUCTION; ANGULAR-DISTRIBUTION; 800 GEV/C; PARTON DISTRIBUTIONS; HADRON COLLISIONS; DIMUON PRODUCTION; PSI' PRODUCTION AB Recent results from fixed-target dimuon production experiments at Fermilab are presented. Various QCD tests using dilepton production data are discussed. We emphasize that clear evidence for scaling violation in the Drell-Yan process remains to be established. Further theoretical and experimental work are needed to understand the polarization of the Drell-Yan pairs. We also discuss the nuclear medium effects for dilepton productions. In particular, we discuss the use of Drell-Yan data to deduce the energy-loss of partons traversing nuclear medium. C1 Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. RP Peng, JC (reprint author), Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. NR 36 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 1-56396-908-4 J9 AIP CONF PROC PY 1999 VL 494 BP 503 EP 512 PG 10 WC Physics, Particles & Fields SC Physics GA BP14H UT WOS:000084221500043 ER PT J AU Rice, JE Fournier, KB Safronova, UI Goetz, JA Gutmann, S Hubbard, AE Irby, J LaBombard, B Marmar, ES Terry, JL AF Rice, J. E. Fournier, K. B. Safronova, U. I. Goetz, J. A. Gutmann, S. Hubbard, A. E. Irby, J. LaBombard, B. Marmar, E. S. Terry, J. L. TI The Rydberg series of helium-like Cl, Ar and S and their high-n satellites in tokamak plasmas SO NEW JOURNAL OF PHYSICS LA English DT Article AB The Rydberg series up to n = 14 of helium-like chlorine, argon and sulfur have been observed in Alcator C-Mod plasmas. High-n satellites to these lines of the form 1s(2)2s-1s2snp and 1s(2)2p-1s2pnp with 3 <= n <= 12 have also been seen for chlorine and argon. Accurate wavelengths of these satellites have been obtained, comparison has been made with the theoretical predictions from the atomic structure codes RELAC and MZ, and the agreement is good. Measured line intensities have also been compared with collisional radiative modelling that includes the contributions from dielectronic recombination and inner-shell excitation rates to each line's emission, again with good agreement. C1 [Rice, J. E.; Goetz, J. A.; Hubbard, A. E.; Irby, J.; LaBombard, B.; Marmar, E. S.; Terry, J. L.] MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. [Fournier, K. B.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. [Safronova, U. I.] Notre Dame Univ, Notre Dame, IN 46556 USA. [Gutmann, S.] Northeastern Univ, Boston, MA 02116 USA. RP Rice, JE (reprint author), MIT, Plasma Sci & Fus Ctr, 77 Massachusetts Ave, Cambridge, MA 02139 USA. FU MIT by DoE [DE-FC02-99ER54512]; LLNL by DoE [W-7405-ENG-48] FX The authors would like to thank the Alcator C-Mod operations group for expert running of the tokamak. Work supported at MIT by DoE contract no DE-FC02-99ER54512 and at LLNL by DoE contract no W-7405-ENG-48. NR 61 TC 7 Z9 7 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 1367-2630 J9 NEW J PHYS JI New J. Phys. PY 1999 VL 1 AR PII S1367-2630(99)05782-1 DI 10.1088/1367-2630/1/1/319 PG 27 WC Physics, Multidisciplinary SC Physics GA V25DU UT WOS:000208459500017 ER PT B AU Phillips, C Swiler, LP AF Phillips, C Swiler, LP GP ACM ACM TI A graph-based system for network-vulnerability analysis SO NEW SECURITY PARADIGMS WOEKSHOP, PROCEEDINGS LA English DT Proceedings Paper CT 7th New Security Paradigms Workshop CY SEP 22-25, 1998 CL CHARLOTTESVILLE, VA SP Assoc Comp Mach Special Interest Grp Security, Audit & Control DE computer security; network vulnerability; attack graph AB This paper presents a graph-based approach to network vulnerability analysis. The method is flexible, allowing analysis of attacks from both outside and inside the network. It can analyze risks to a specific network asset, or examine the universe of possible consequences following a successful attack. The graph-based tool can identify the set of attack paths that have a high probability of success (or a low "effort" cost) for the attacker. The system could be used to test the effectiveness of making configuration changes, implementing an intrusion detection system, etc. The analysis system requires as input a database of common attacks, broken into atomic steps, specific network configuration and topology information, and an attacker profile. The attack information is "matched" with the network configuration information and an attacker profile to create a superset attack graph. Nodes identify a stage of attack, for example the class of machines the attacker has accessed and the user privilege level he or she has compromised. The arcs in the attack graph represent attacks or stages of attacks. By assigning probabilities of success on the arcs or costs representing level-of-effort for the attacker, various graph algorithms such as shortest-path algorithms can identify the attack paths with the highest probability of success. C1 Sandia Natl Labs, Albuquerque, NM 87105 USA. RP Phillips, C (reprint author), Sandia Natl Labs, MS 1110, Albuquerque, NM 87105 USA. NR 18 TC 1 Z9 1 U1 1 U2 1 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036-9998 USA BN 1-58113-168-2 PY 1999 BP 71 EP 79 PG 9 WC Computer Science, Information Systems; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BN41S UT WOS:000081877800008 ER PT B AU Drell, SD Sofaer, AD Wilson, GD AF Drell, SD Sofaer, AD Wilson, GD BE Drell, SD Sofaer, AD Wilson, GD TI The new terror - Facing the threat of biological and chemical weapons - Overview SO NEW TERROR: FACING THE THREAT OF BIOLOGICAL AND CHEMICAL WEAPONS SE HOOVER NATIONAL SECURITY FORUM SERIES LA English DT Proceedings Paper CT Conference on Biological and Chemical Weapons CY NOV 16-18, 1998 CL STANFORD UNIV, HOOVER INST, STANFORD, CA SP Stanford Univ, Hoover Inst HO STANFORD UNIV, HOOVER INST C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU HOOVER INST PRESS PI STANFORD PA STANFORD UNIV, STANFORD, CA 94305-6010 USA BN 0-8179-9701-6 J9 HOOVER NATL SECUR FO PY 1999 BP XVII EP XXVII PG 11 WC International Relations SC International Relations GA BQ06U UT WOS:000087044700002 ER PT S AU Alves, DR Basu, A Cook, KH Welch, DL AF Alves, DR Basu, A Cook, KH Welch, DL CA MACHO Collaboration BE Chu, YH Suntzeff, NB Hesser, JE Bohlender, DA TI The MACHO project LMC variable star inventory: Classical cepheids, AGB variables, and the nine million star color-magnitude diagram SO NEW VIEWS OF THE MAGELLANIC CLOUDS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 190th Symposium of the International-Astronomical-Union CY JUL 12-17, 1998 CL VICTORIA, CANADA SP Int Astron Union, Canadian Inst Theoret Astrophys, Univ Victoria, Dept Phys & Astron, Herzberg Inst Astrophys, Natl Res Council ID CLUSTERS AB We measure the ratio of similar to 5M(circle dot) blue and red LMC supergiants (representative of classical Cepheids) using the MACHO Project's 9 million star color-magnitude diagram (9M CMD) of the LMC bar. We find b/r = 0.39, which favors the Z=0.008, 5M(circle dot) theoretical model of Schaerer et al. (1993) over that of Fagatto et al. (1994). Next, we examine the low mass (old) and low metallicity LMC field population (Pop. II). Features in the 9M CMD and properties of LMC field RRab variables are consistent with a mean iron abundance of [Fe/H] approximate to -1.5 dex for this population. Newly discovered post-HB/early-AGB Pop. II variables are identified in order to delineate the instability strip (IS). Good agreement with the theoretical IS of Bono et al. (1997) is found. We then compare the field RRab with newly identified RRab variables in the LMC clusters NGC 1898 and NGC 1835. We find the mean colors of these cluster RRab lie near the red and blue edges of the IS, respectively, which is similar to their respective (overall) red and blue HB morphologies. Since the field RRab lie on the red side of the IS, we infer the LMC field Pop. II is likely to have a red HB morphology. C1 Univ Calif Davis, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. McMaster Univ, Hamilton, ON L8S 4M1, Canada. RP Alves, DR (reprint author), Univ Calif Davis, Davis, CA 95616 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-021-8 J9 IAU SYMP PY 1999 IS 190 BP 517 EP 522 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU32Y UT WOS:000175704600146 ER PT B AU Huang, P Myer, LR Yang, G AF Huang, P Myer, LR Yang, G BE Vouille, G Berest, P TI Network modelling of multiphase flow processes in rock SO NINTH INTERNATIONAL CONGRESS ON ROCK MECHANICS, VOLS 1 & 2 LA English DT Proceedings Paper CT 9th International Congress on Rock Mechanics CY AUG 25-28, 1999 CL PARIS, FRANCE SP Bur Rech Geol & Min, Com Francais Mecan Sols, Com Francais Geol Ingn AB A pore level network simulator was developed and used to study the relationship between pore microstructure and macroscopic flow properties. The network is based on a regular 3D lattice which is populated by pores and pore throats based on pore space statistics. Graph theory is used to perform efficient path searches for modeling invasion/drainage processes. Absolute permeability was found to be sensitive to porosity, pore and throat size (and their ratio) and the variation in pore sizes. Relative permeability was found to be most sensitive to the distribution of pore sizes and the geometric shape of the pore throats. Good agreement was found between simulations and laboratory measurements on a range of sandstone rocks. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Huang, P (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 8 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 90-5809-070-1 PY 1999 BP 509 EP 513 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA BP03Z UT WOS:000083950400104 ER PT B AU Nakagawa, S Hopkins, D Gentier, S Riss, J AF Nakagawa, S Hopkins, D Gentier, S Riss, J BE Vouille, G Berest, P TI Hydromechanical behavior of fractures in shear: Implications for seismic imaging SO NINTH INTERNATIONAL CONGRESS ON ROCK MECHANICS, VOLS 1 & 2 LA English DT Proceedings Paper CT 9th International Congress on Rock Mechanics CY AUG 25-28, 1999 CL PARIS, FRANCE SP Bur Rech Geol & Min, Com Francais Mecan Sols, Com Francais Geol Ingn ID ROCK JOINTS; TRANSMISSION; WAVES AB A casting technique used to produce replicas of natural fractures allows measurements of the fractures' hydromechanical response during successive stages of shearing to be related to the topography of the fracture surfaces and the geometry of the void space between them. Casts capture the fracture topography at each stage; images of the casts are used to map damage on the fracture surfaces and to provide input to mechanical and flow models. The mechanical models are used to study redistribution of stress, changes in void space geometry, and failure at contact points, which helps interpret laboratory results showing the evolution of damage zones and flow paths during shearing. Theoretical and experimental results demonstrate the conversion of seismic waves that occurs at fractures under a shear stress. The characteristics of the converted waves depend on the magnitude and orientation of the shear stress, which, in turn, can be related to hydromechanical behavior. C1 EO Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Nakagawa, S (reprint author), EO Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 17 TC 0 Z9 0 U1 0 U2 2 PU A A BALKEMA PUBLISHERS PI LEIDEN PA SCHIPHOLWEG 107C, PO BOX 447, 2316 XC LEIDEN, NETHERLANDS BN 90-5809-070-1 PY 1999 BP 947 EP 951 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA BP03Z UT WOS:000083950400189 ER PT B AU Nakagawa, S Nihei, NT Myer, LR AF Nakagawa, S Nihei, NT Myer, LR BE Vouille, G Berest, P TI Frequency-dependent acoustic anisotropy in fractured rock SO NINTH INTERNATIONAL CONGRESS ON ROCK MECHANICS, VOLS 1 & 2 LA English DT Proceedings Paper CT 9th International Congress on Rock Mechanics CY AUG 25-28, 1999 CL PARIS, FRANCE SP Bur Rech Geol & Min, Com Francais Mecan Sols, Com Francais Geol Ingn ID MEDIA AB Frequency-dependent acoustic wave propagation in fractured rock is examined for a set of equally-spaced, parallel fractures. Exact solutions for the velocity of the waves are obtained as a function of wave frequency and fracture stiffness and spacing. Waves propagating obliquely to the fractures show strongly anisotropic velocities for low fracture stiffnesses and high frequencies. For high frequencies, propagation of the waves is sometimes prohibited due to the interference of multiply scattered waves (stop-pass behavior). For the waves propagating parallel to the fractures, multiple guided modes are shown to exist with velocities and particle motions that are dependent on fracture stiffness and frequency. C1 EO Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA USA. RP Nakagawa, S (reprint author), EO Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA USA. NR 22 TC 0 Z9 0 U1 0 U2 1 PU A A BALKEMA PUBLISHERS PI LEIDEN PA SCHIPHOLWEG 107C, PO BOX 447, 2316 XC LEIDEN, NETHERLANDS BN 90-5809-070-1 PY 1999 BP 953 EP 957 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA BP03Z UT WOS:000083950400190 ER PT B AU George, JT Finley, RE Riggins, M AF George, JT Finley, RE Riggins, M BE Vouille, G Berest, P TI Determination of rock mass modulus using the plate loading method SO NINTH INTERNATIONAL CONGRESS ON ROCK MECHANICS, VOLS 1 & 2 LA English DT Proceedings Paper CT 9th International Congress on Rock Mechanics CY AUG 25-28, 1999 CL PARIS, FRANCE SP Bur Rech Geol & Min, Com Francais Mecan Sols, Com Francais Geol Ingn AB A suite of plate loading tests has recently been conducted by Sandia National Laboratories at the Exploratory Studies Facility at Yucca Mountain, Nevada. Fielding of these in situ tests as well as other approaches undertaken for the determination of rock mass modulus are described. The various methodologies are evaluated and their data compared. Calculation by existing empirical methods and numerical modeling are compared to each other as well as to field data. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP George, JT (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 21 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 90-5809-070-1 PY 1999 BP 1367 EP 1371 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA BP03Z UT WOS:000083950400269 ER PT S AU Moore, KR Blain, P AF Moore, KR Blain, P BE Lindblad, T Padgett, ML Kinser, J TI Spectral recognition with a PCNN preprocessor SO NINTH WORKSHOP ON VIRTUAL INTELLIGENCE/DYNAMIC NEURAL NETWORKS: ACADEMIC/INDUSTRIAL/NASA/DEFENSE TECHNICAL INTERCHANGE AND TUTORIALS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 9th Workshop on Virtual Intelligence/Dynamic Neural Networks CY JUN 22-28, 1998 CL ROYAL INST TECHNOL, STOCKHOLM, SWEDEN SP NASA, SPIE - Int Soc Opt Engn, IEEE Ind Applicat Soc HO ROYAL INST TECHNOL DE pulse coded neural networks; spectral recognition AB This is a report on work in progress. Spectral recognition is central to many areas of science and technology. Classical spectral recognition analysis techniques (least squares, partial least squares, etc.) are sensitive to offset and gain drifts and errors. This sensitivity can cause excessive costs for spectrometer resources and calibrations. Neural techniques relieve some of this sensitivity but none approach human competence. It is desirable to mimic human spectral analysis not only to improve the results but to minimize detector constraints and costs. We suggest that the first step in human analysis is peak detection. We are exploring the one dimensional PCNN as a peak segmenter for spectral peak finding in the presence of noise and drifts in gain and offset. We present results of one dimensional pulse coded neural network peak detection with both simulated and actual static spectra. We also use the PCNN to form a scale and translation invariant feature vector that may be decomposed using classical techniques such as least squares. Finally, we propose using a PCNN to exploit the temporal aspects of spectral acquisition. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Moore, KR (reprint author), Univ Calif Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. NR 2 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 0-8194-3202-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3728 BP 328 EP 332 DI 10.1117/12.343051 PG 5 WC Engineering, Aerospace; Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Optics SC Engineering; Computer Science; Optics GA BM94V UT WOS:000080215800030 ER PT S AU del-Castillo-Negrete, D Finn, JM Barnes, DC AF del-Castillo-Negrete, D Finn, JM Barnes, DC BE Bollinger, JJ Spencer, RL Davidson, RC TI The modified drift-Poisson model: analogies with geophysical flows and Rossby waves SO NON-NEUTRAL PLASMA PHYSICS III SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Non-Neutral Plasma Physics CY AUG 02-05, 1999 CL PRINCETON UNIV, PRINCETON, NJ SP USN, Off Res, US DOE, Princeton Plasma Phys Lab, Princeton Univ HO PRINCETON UNIV ID ELECTRON AB We discuss an analogy between magnetically confined nonneutral plasmas and geophysical fluid dynamics. The analogy has its roots in the modified drift Poisson model, a recently proposed model that takes into account the plasma compression due to the variations of the plasma length [1]. The conservation of the line integrated density in the new model is analogous to the conservation of potential vorticity in the shallow water equations, and the variation of the plasma length is isomorphic to variations in the Coriolis parameter with latitude or to topography variations in the quasigeostrophic dynamics. We discuss a new class of linear and nonlinear waves that owe their existence to the variations of the plasma length. These modes are the analog of Rossby waves in geophysical flows. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP del-Castillo-Negrete, D (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 8 TC 2 Z9 2 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 1-56396-913-0 J9 AIP CONF PROC PY 1999 VL 498 BP 147 EP 152 PG 6 WC Physics, Fluids & Plasmas SC Physics GA BP30A UT WOS:000084618900021 ER PT S AU Finn, JM del-Castillo-Negrete, D Barnes, DC AF Finn, JM del-Castillo-Negrete, D Barnes, DC BE Bollinger, JJ Spencer, RL Davidson, RC TI The m=1 diocotron instability in single species plasmas SO NON-NEUTRAL PLASMA PHYSICS III SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Non-Neutral Plasma Physics CY AUG 02-05, 1999 CL PRINCETON UNIV, PRINCETON, NJ SP USN, Off Res, US DOE, Princeton Plasma Phys Lab, Princeton Univ HO PRINCETON UNIV ID HOLLOW ELECTRON COLUMNS; NONNEUTRAL PLASMA; EQUILIBRIA; LENGTH; MODEL AB According to conventional theory based on the drift-Poisson equations, the m = 1 diocotron mode is stable, even for hollow density profiles. However, experiments[C. F. Driscoll, Phys. Rev. Lett. 64, 645 (1990)] show instability for this mode. These results have remained unexplained since 1990. We have found two effects, related to compression parallel to the magnetic field, which lead to instability with growth rates and other properties in good agreement with the experiments. The first; is due to curvature of the sheaths at the ends of the trap. The second is the free boundary effect due to the linearized perturbation of the plasma length. These effects are described in terms of the modified drift-Poisson model, which states the conservation of the line integrated density. The modified drift-Poisson equations derived are analogous to the shallow water equations of geophysical fluid dynamics (GFD), with the line integrated density corresponding to the potential vorticity. This is explained in more detail in [del-Castillo-Negrete et al., this volume]. More recent experimental results[A. A. Kabantsev and C. F. Driscoll, this volume] show agreement over a wider range of parameters than the original experiments. We study the m = 2 mode and show that curvature and free boundary effects can increase the growth rate, but it is still small compared to that of the m = 1 mode for realistic parameters, and the critical hollowness far stability is much greater. Results are also shown for m = 1 modes in the analogous GFD system. It is shown that topography variation in cylindrical geometry and free surface effects both lead to instability with properties similar to those in the plasma models. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Finn, JM (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. NR 17 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 1-56396-913-0 J9 AIP CONF PROC PY 1999 VL 498 BP 198 EP 207 PG 10 WC Physics, Fluids & Plasmas SC Physics GA BP30A UT WOS:000084618900028 ER PT S AU Chao, EH Davidson, RC Paul, SF Morrison, KA AF Chao, EH Davidson, RC Paul, SF Morrison, KA BE Bollinger, JJ Spencer, RL Davidson, RC TI Effects of background gas pressure on pure electron plasma dynamics in the electron diffusion gauge experiment SO NON-NEUTRAL PLASMA PHYSICS III SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Non-Neutral Plasma Physics CY AUG 02-05, 1999 CL PRINCETON UNIV, PRINCETON, NJ SP USN, Off Res, US DOE, Princeton Plasma Phys Lab, Princeton Univ HO PRINCETON UNIV ID NEUTRAL GAS; ELASTIC COLLISIONS; EXPANSION; WAVES; TIME AB A pure electron plasma is confined in a Malmberg-Penning trap and its confinement and stability properties are studied. Of particular interest are the effects that collisions between plasma electrons and background neutral gas atoms have on the plasma expansion and on the evolution of the m = 1 diocotron mode. Essential features of the m = 1 diocotron mode dynamics in the absence of electron-neutral collisions have been verified to behave as expected. The mode frequency, the resistive growth rates, and the frequency shift at nonlinearly large amplitudes are all in good agreement with predictions. When background neutral gas is injected, the evolution of the mode amplitude is found to be sensitive to the gas pressure down to pressures of 5 x 10(-10) Torr, the lowest base pressure achieved in the EDG device. The evolution of the plasma density profile has also been monitored in order to examine the shape of the evolving density profile, and to measure the expansion rate. The density profile has been observed to expand radially while maintaining a. thermal equilibrium profile shape, as has been predicted theoretically. The plasma expansion rate is affected by the background neutral gas pressure, but the measured expansion rate is generally faster than the expansion rate predicted by considering only electron-neutral collisions. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Chao, EH (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 14 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-913-0 J9 AIP CONF PROC PY 1999 VL 498 BP 278 EP 289 PG 12 WC Physics, Fluids & Plasmas SC Physics GA BP30A UT WOS:000084618900038 ER PT S AU Davidson, RC Qin, H Shvets, G AF Davidson, RC Qin, H Shvets, G BE Bollinger, JJ Spencer, RL Davidson, RC TI Intense nonneutral beam propagation through a periodic focusing quadrupole field I - A compact Paul trap configuration to simulate beam propagation over large distances SO NON-NEUTRAL PLASMA PHYSICS III SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Non-Neutral Plasma Physics CY AUG 02-05, 1999 CL PRINCETON UNIV, PRINCETON, NJ SP USN, Off Res, US DOE, Princeton Plasma Phys Lab, Princeton Univ HO PRINCETON UNIV ID VLASOV-MAXWELL EQUATIONS; CHARGED-PARTICLE BEAMS; STABILITY THEOREM AB This paper considers an intense nonneutral charged particle beam propagating in the z-direction through a periodic focusing quadrupole magnetic field with transverse focusing force, -kappa(q)(s)[x (e) over cap(x) - y (e) over cap(y)] on the beam particles. Here, s = beta(b)ct is the axial coordinate, (gamma(b) - 1)m(b)c(2) is the directed axial kinetic energy of the beam particles, q(b) and m(b) are the charge and rest mass, respectively, of a beam particle, and the oscillatory lattice coefficient satisfies kappa(q)(s + S) = kappa(q)(S), where S is the axial periodicity length of the focusing field. The particle motion in the beam frame is assumed to be nonrelativistic, and the Vlasov-Maxwell equations are employed to describe the collisionless nonlinear evolution of the distribution function f(b) (x, y, x', y', s) and the (normalized) self field potential psi(x, y, s) = q(b)phi(x, y, s)/gamma(b)(3)m(b)beta(b)(2)c(2) in the transverse laboratory-frame phase space (x, y, x', y'), assuming a thin beam with characteristic radius r(b) much less than S. It is shown that collective processes and the nonlinear transverse beam dynamics can be fully simulated in a compact Paul trap configuration in which a long nonneutral plasma column (L much greater than rp) is confined axially by applied de voltages (V) over cap = const. on end cylinders at z = +/-L, and transverse confinement in the x - y plane is provided by segmented cylindrical electrodes (at radius r(w)) with applied oscillatory voltages +/-V-0(t) over 90 degrees segments. Here, V-0(t + T) = V-0(t), where T = const. is the oscillation period, and the oscillatory quadrupole focusing force on a particle with charge q and mass m near the cylinder axis is -m kappa(q)(t)[x (e) over cap(x) - y (e) over cap(y)](,) where kappa(q)(t) = 8qV(0)(t)/pi mr(w)(2). This configuration offers the possibility of simulating intense beam propagation over large distances in a compact configuration which is stationary in the laboratory frame. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Davidson, RC (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 32 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 1-56396-913-0 J9 AIP CONF PROC PY 1999 VL 498 BP 309 EP 319 PG 11 WC Physics, Fluids & Plasmas SC Physics GA BP30A UT WOS:000084618900041 ER PT S AU Davidson, RC Qin, H Shvets, G AF Davidson, RC Qin, H Shvets, G BE Bollinger, JJ Spencer, RL Davidson, RC TI Intense nonneutral beam propagation through a periodic focusing quadrupole field II - Hamiltonian averaging techniques in the smooth-focusing approximation SO NON-NEUTRAL PLASMA PHYSICS III SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Non-Neutral Plasma Physics CY AUG 02-05, 1999 CL PRINCETON UNIV, PRINCETON, NJ SP USN, Off Res, US DOE, Princeton Plasma Phys Lab, Princeton Univ HO PRINCETON UNIV ID VLASOV-MAXWELL EQUATIONS; CHARGED-PARTICLE BEAMS AB This paper considers a compact Paul trap configuration to model the transverse nonlinear dynamics of an intense charged particle beam propagating through a periodic focusing quadrupole magnetic field in the collisionless regime. A long nonneutral plasma column (L much greater than r(p)) is confined axially by applied de voltages (V) over cap = const. on end cylinders z = +/-L, and transverse confinement of the particles in the x - y plane is provided by segmented cylindrical electrodes (at radius r(w)) with applied oscillatory voltages +/-V-0(t) over 90 degrees segments. Here, V-0(t + T) = V-0(t), where T = const. is the oscillation period. Neglecting axial variations (partial derivative/partial derivative z = 0), the Hamiltonian describing the transverse motion (assumed nonrelativistic) of a particle with charge q and mass rn near the cylinder axis (r(p) much less than 1,) is given by H-perpendicular to(x, y, (x) over dot, (y) over dot, t) = (m/2) ((x) over dot (2) + (y) over dot (2)) + (m/2)kappa(q)(t)(x(2) - y(2)) + q phi(s)(x, y, t), where phi(s)(x, y, t) is the self-field electrostatic potential, and kappa(q)(t) = 8qV(0)(t)/pi mr(w)(2) is the (oscillatory) quadrupole focusing coefficient due to the applied held. Using a third-order Hamiltonian averaging technique [R. C. Davidson, H. Qin, and P. J. Channell, Physical Review Special Topics on Accelerators and Beams 2, 074401 (1999)], a canonical transformation is employed that utilizes an expanded generating function that transforms away the rapidly oscillating terms in the Hamiltonian H-perpendicular to(x, y, (x) over dot, (y) over dot, t). Formally, epsilon = \<(kappa)over cap>(q)\T-2/(2 pi)(2) < 1 is treated as a small dimensionless parameter, where <(kappa)over cap>(q) is the characteristic (maximum) amplitude of the applied quadrupole field, and the canonical transformation is carried out correct to order epsilon(3). This leads to a Hamiltonian, H-perpendicular to((X) over tilde, (Y) over tilde, (X) over tilde, (Y) over tilde, t) = (m/2)((X) over tilde(2) + (Y) over tilde(2)) + (m/2)(w) over cap(q)(2)((X) over tilde(2) + (Y) over tilde(2)) + phi(s)((X) over tilde, (Y) over tilde, t), correct to order epsilon(3) in the 'slow' transformed variables ((X) over tilde, (Y) over tilde, (X) over tilde, (Y) over tilde). Here, the transverse focusing coefficient in the transformed variables satisfies (w) over cap(q)(2) = const., leading to enormous simplification in the analysis of the nonlinear Vlasov-Poisson equations for F((X) over tilde, (Y) over tilde, (X) over tilde, (Y) over tilde, t) and phi(s)((X) over tilde, (Y) over tilde, t). C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Davidson, RC (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 13 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 1-56396-913-0 J9 AIP CONF PROC PY 1999 VL 498 BP 320 EP 328 PG 9 WC Physics, Fluids & Plasmas SC Physics GA BP30A UT WOS:000084618900042 ER PT S AU Murillo, MS AF Murillo, MS BE Bollinger, JJ Spencer, RL Davidson, RC TI Collective modes in strongly coupled dusty plasmas SO NON-NEUTRAL PLASMA PHYSICS III SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Non-Neutral Plasma Physics CY AUG 02-05, 1999 CL PRINCETON UNIV, PRINCETON, NJ SP USN, Off Res, US DOE, Princeton Plasma Phys Lab, Princeton Univ HO PRINCETON UNIV ID LOCAL-FIELD CORRECTION; WAVES AB Dusty plasmas offer a new setting for exploring dynamical phenomena in the strong coupling regime. In contrast to nonneutral plasmas, screening occurs in the dusty plasma and the effective interaction is approximately of a Yukawa form; this leads to acoustic-like modes rather than Langmuir-like modes. Dust acoustic waves thus have a dispersion relation that exists for vary low and very high frequencies and wavevectors. Here the interpolation ansatz method is used to construct a strong coupling theory that is valid over this range. In this method the correct hydrodynamic limit is recovered and the lowest-order sum rules are satisfied. C1 Univ Calif Los Alamos Natl Lab, Plasma Phys Applicat Grp, Los Alamos, NM 87545 USA. RP Murillo, MS (reprint author), Univ Calif Los Alamos Natl Lab, Plasma Phys Applicat Grp, MS B259, Los Alamos, NM 87545 USA. NR 9 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 1-56396-913-0 J9 AIP CONF PROC PY 1999 VL 498 BP 376 EP 382 PG 7 WC Physics, Fluids & Plasmas SC Physics GA BP30A UT WOS:000084618900048 ER PT S AU Schauer, MM Umstadter, KR Barnes, DC AF Schauer, MM Umstadter, KR Barnes, DC BE Bollinger, JJ Spencer, RL Davidson, RC TI The Penning fusion experiment - Ions SO NON-NEUTRAL PLASMA PHYSICS III SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Non-Neutral Plasma Physics CY AUG 02-05, 1999 CL PRINCETON UNIV, PRINCETON, NJ SP USN, Off Res, US DOE, Princeton Plasma Phys Lab, Princeton Univ HO PRINCETON UNIV ID TRAP AB The Penning fusion experiment (PFX) studies the feasibility of using a Penning trap as a fusion confinement device. Such use would require spatial and/or temporal compression of the plasma to overcome the Brillouin density limit imposed by the nonneutrality of Penning trap plasmas. In an earlier experiment, we achieved enhanced plasma density at the center of a pure, electron plasma confined in a hyperbolic, Penning trap by inducing spherically convergent flow in a nonthermal plasma(1,2,3). The goal of this work is to induce similar flow in a positive ion plasma confined in the virtual cathode provided by a spherical, uniform density electron plasma. This approach promises the greatest flexibility in operating with multi-species plasmas (e.g. D+/T+) or implementing temporal compression schemes such as the Periodically Oscillating Plasma Sphere of Nebel and Barnes(4,5). Here, we report on our work to produce and diagnose the necessary electron plasma. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Schauer, MM (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-913-0 J9 AIP CONF PROC PY 1999 VL 498 BP 425 EP 434 PG 10 WC Physics, Fluids & Plasmas SC Physics GA BP30A UT WOS:000084618900055 ER PT S AU Paul, SF Chao, EH Davidson, RC Phillips, CK AF Paul, SF Chao, EH Davidson, RC Phillips, CK BE Bollinger, JJ Spencer, RL Davidson, RC TI Confinement of pure ion plasma in a cylindrical current sheet SO NON-NEUTRAL PLASMA PHYSICS III SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Non-Neutral Plasma Physics CY AUG 02-05, 1999 CL PRINCETON UNIV, PRINCETON, NJ SP USN, Off Res, US DOE, Princeton Plasma Phys Lab, Princeton Univ HO PRINCETON UNIV ID FUSION AB A novel method for containing a pure ion plasma at thermonuclear densities and temperatures has been modeled. The method combines the confinement principles of a Penning-Malmberg trap and a pulsed theta-pinch. A conventional Penning trap can confine a uniform-density plasma of about 5x10(11)cm(-3) with a SO-Tesla magnetic field. However, if the axial field is ramped, a much higher local ion density can be obtained. Starting with a 10(7) cm(-3) trapped deuterium plasma at the Brillouin limit (B = 0.6 Tesla), the field is ramped to 30 Tesla. Because the plasma is comprised of particles of only one sign of charge, transport losses are very low, i.e., the conductivity is high. As a result, the ramped field does not penetrate the plasma and a diamagnetic surface current is generated, with the ions being accelerated to relativistic velocities. To counteract the inward j x B forces from this induced current, additional ions are injected into the plasma along the axis to increase the density (and mutual electrostatic repulsion) of the target plasma. In the absence of the higher magnetic field in the center, the ions drift outward until a balance is established between the outward driving forces (centrifugal, electrostatic, pressure gradient) and the inward j x B force. An equilibrium calculation using a relativistic, 1-D, cold-fluid model shows that a plasma can be trapped in a hollow, 49-cm diameter, 0.2-cm thick; cylinder with a density exceeding 4 x 10(14) cm(-3). C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Paul, SF (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 5 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 1-56396-913-0 J9 AIP CONF PROC PY 1999 VL 498 BP 435 EP 444 PG 10 WC Physics, Fluids & Plasmas SC Physics GA BP30A UT WOS:000084618900056 ER PT S AU Chao, EH Davidson, RC Paul, SF Fine, KS AF Chao, EH Davidson, RC Paul, SF Fine, KS BE Bollinger, JJ Spencer, RL Davidson, RC TI Self-consistent numerical solution to Poisson's equation in an axisymmetric Malmberg-Penning trap SO NON-NEUTRAL PLASMA PHYSICS III SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Non-Neutral Plasma Physics CY AUG 02-05, 1999 CL PRINCETON UNIV, PRINCETON, NJ SP USN, Off Res, US DOE, Princeton Plasma Phys Lab, Princeton Univ HO PRINCETON UNIV AB This paper summarizes a fast numerical technique for solving Poisson's equation in an axisymmetric Malmberg-Penning trap. The method assumes the charge density qn(r, z) and boundary potentials phi(r = R-w, z) are specified, and serves for the electrostatic potential phi(r, z) within the cylinder. The solution of Poisson's equation is often an important step in the numerical reconstruction of the nonneutral plasma density profile n(r, z) from the axially integrated measurements of the charge density profile, Q(r) = qA(h) integral dz n(r, z), where q is the charge and A(h) is the effective area of the collimator hole. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Chao, EH (reprint author), Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-913-0 J9 AIP CONF PROC PY 1999 VL 498 BP 461 EP 468 PG 8 WC Physics, Fluids & Plasmas SC Physics GA BP30A UT WOS:000084618900060 ER PT S AU Telschow, KL Deason, VA Schley, RS Watson, SM AF Telschow, KL Deason, VA Schley, RS Watson, SM BE Green, RE TI Direct imaging of anisotropic material properties using photorefractive laser ultrasound SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS IX SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Symposium on Nondestructive Characterization of Materials CY JUN 28-JUL 02, 1999 CL SYDNEY, AUSTRALIA SP Amer Soc Nondestruct Testing, NASA, Langley Res Ctr, Natl Sci Fdn, USN, Off Res, USA, Res Off Far E, USAF, Asian Off Aerosp R&D, USN, Off Res Int Field Off Asia AB Anisotropic properties of materials can be determined by measuring the propagation of elastic waves in different directions. A laser imaging approach is presented that utilizes the adaptive property of photorefractive materials to produce a real-time measurement of the antisymmetric Lamb or flexural traveling wave made displacement and phase. Continuous excitation is employed and the data is recorded and displayed in all directions simultaneously at video camera frame rates. Fourier transform of the data produces an image of the wave slowness in all planar directions. The results demonstrate imaging of microstructural isotropy and anisotropy and stress induced ansiotropy in plates. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Telschow, KL (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RI Schley, Robert/B-9124-2017 OI Schley, Robert/0000-0001-8907-6535 NR 7 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-911-4 J9 AIP CONF PROC PY 1999 VL 497 BP 162 EP 167 PG 6 WC Materials Science, Characterization & Testing; Physics, Applied SC Materials Science; Physics GA BP29Z UT WOS:000084618600024 ER PT S AU Thomas, G Chinn, D AF Thomas, G Chinn, D BE Green, RE TI Signal analysis approach to ultrasonic evaluation of diffusion bond quality SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS IX SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Symposium on Nondestructive Characterization of Materials CY JUN 28-JUL 02, 1999 CL SYDNEY, AUSTRALIA SP Amer Soc Nondestruct Testing, NASA, Langley Res Ctr, Natl Sci Fdn, USN, Off Res, USA, Res Off Far E, USAF, Asian Off Aerosp R&D, USN, Off Res Int Field Off Asia AB Solid state bonds like the diffusion bond are attractive techniques for joining dissimilar materials since they are not prone to the defects that occur with fusion welding. Ultrasonic methods can detect the presence of totally unbonded regions but have difficulty sensing poor bonded areas where the substrates are in intimate contact. Standard ultrasonic imaging is based on amplitude changes in the signal reflected from the bond interface. Unfortunately, amplitude alone is not sensitive to bond quality. We demonstrated that there is additional information in the ultrasonic signal that correlates with bond quality. In our approach, we interrogated a set of dissimilar diffusion bonded samples with broad band ultrasonic signals. The signals were digitally processed and the characteristics of the signals that corresponded to bond quality were determined. These characteristics or features were processed with pattern recognition algorithms to produce predictions of bond quality. The predicted bond quality was then compared with the destructive measurement to assess the classification capability of the ultrasonic technique. C1 Univ Calif Lawrence Livermore Natl Lab, Mfg & Mat Engn Dept, Livermore, CA 94550 USA. RP Thomas, G (reprint author), Univ Calif Lawrence Livermore Natl Lab, Mfg & Mat Engn Dept, Livermore, CA 94550 USA. NR 6 TC 2 Z9 2 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 1-56396-911-4 J9 AIP CONF PROC PY 1999 VL 497 BP 536 EP 542 PG 7 WC Materials Science, Characterization & Testing; Physics, Applied SC Materials Science; Physics GA BP29Z UT WOS:000084618600082 ER PT S AU Martz, HE Roberson, GP Hollerbach, K Logan, CM Ashby, E Bernardi, R AF Martz, HE Roberson, GP Hollerbach, K Logan, CM Ashby, E Bernardi, R BE Green, RE TI Computed tomography of human joints and radioactive waste drums SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS IX SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Symposium on Nondestructive Characterization of Materials CY JUN 28-JUL 02, 1999 CL SYDNEY, AUSTRALIA SP Amer Soc Nondestruct Testing, NASA, Langley Res Ctr, Natl Sci Fdn, USN, Off Res, USA, Res Off Far E, USAF, Asian Off Aerosp R&D, USN, Off Res Int Field Off Asia ID GAMMA AB X- and gamma-ray imaging techniques in nondestructive evaluation (NDE) and assay (NDA) have seen increasing use in an array of industrial, environmental, military, and medical applications. Much of this growth in recent years is attributed to the rapid development of computed tomography (CT) and the use of NDE throughout the life-cycle of a product. Two diverse examples of CT are discussed, 1.) Our computational approach to normal joint kinematics and prosthetic joint analysis offers an opportunity to evaluate and improve prosthetic human joint replacements before they are manufactured or surgically implanted. Computed tomography data from scanned joints are segmented, resulting in the identification of bone and other tissues of interest, with emphasis on the articular surfaces. 2.) We are developing NDE and NDA techniques to analyze closed waste drums accurately and quantitatively. Active and passive computed tomography (A&PCT) is a comprehensive and accurate gamma-ray NDA method that can identify all detectable radioisotopes present in a container and measure their radioactivity. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Martz, HE (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 21 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 1-56396-911-4 J9 AIP CONF PROC PY 1999 VL 497 BP 607 EP 615 PG 9 WC Materials Science, Characterization & Testing; Physics, Applied SC Materials Science; Physics GA BP29Z UT WOS:000084618600092 ER PT S AU Hall, J Dietrich, F Logan, C Schmid, G AF Hall, J Dietrich, F Logan, C Schmid, G BE Green, RE TI Development of high-energy neutron imaging for use in NDE applications SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS IX SE AIP Conference Proceedings LA English DT Proceedings Paper CT 9th International Symposium on Nondestructive Characterization of Materials CY JUN 28-JUL 02, 1999 CL SYDNEY, AUSTRALIA SP Amer Soc Nondestruct Testing, NASA, Langley Res Ctr, Natl Sci Fdn, USN, Off Res, USA, Res Off Far E, USAF, Asian Off Aerosp R&D, USN, Off Res Int Field Off Asia AB We are currently developing a high-energy (10 - 15 MeV) neutron imaging system for use in NDE applications. Our goal is to develop an imaging system capable of detecting cubic-mm-scale voids or other structural defects in heavily-shielded low-Z materials within thick sealed objects. The system will be relatively compact (suitable for use in a small laboratory) and capable of acquiring tomographic image data sets. The design of a prototype imaging detector and multi-axis staging system will be discussed and selected results from recent imaging experiments will be presented. The development of an intense, accelerator-driven neutron source suitable for use with the imaging system will also be discussed. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Hall, J (reprint author), Lawrence Livermore Natl Lab, POB 808,MS L050, Livermore, CA 94551 USA. NR 5 TC 3 Z9 3 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 1-56396-911-4 J9 AIP CONF PROC PY 1999 VL 497 BP 693 EP 698 PG 6 WC Materials Science, Characterization & Testing; Physics, Applied SC Materials Science; Physics GA BP29Z UT WOS:000084618600105 ER PT S AU Aufderheide, MB Park, HS Hartouni, EP Barnes, PD Wright, DM Bionta, RM Zumbro, JD Morris, CL AF Aufderheide, MB Park, HS Hartouni, EP Barnes, PD Wright, DM Bionta, RM Zumbro, JD Morris, CL BE Green, RE TI Proton radiography as a means of material characterization SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS IX SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Symposium on Nondestructive Characterization of Materials CY JUN 28-JUL 02, 1999 CL SYDNEY, AUSTRALIA SP Amer Soc Nondestruct Testing, NASA, Langley Res Ctr, Natl Sci Fdn, USN, Off Res, USA, Res Off Far E, USAF, Asian Off Aerosp R&D, USN, Off Res Int Field Off Asia AB We describe how protons with energies of 800 MeV or greater can be used as radiographic probes for material characterization. A feature which distinguishes protons from x-rays is their charge, which results in multiple Coulomb scattering effects in proton radiographs. Magnetic lensing can ameliorate these effects and even allow mixed substances to be disentangled. We illustrate some of these effects using 800 MeV protons radiographs of a composite step wedge composed of Aluminum, Foam, and Graphite. We discuss how proton radiographs must be manipulated in order to use standard tomographic reconstruction algorithms. We conclude with a brief description of an upcoming experiment, which will be performed at Brookhaven National Laboratory at 25 GeV. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Aufderheide, MB (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 7 TC 2 Z9 2 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 1-56396-911-4 J9 AIP CONF PROC PY 1999 VL 497 BP 706 EP 711 PG 6 WC Materials Science, Characterization & Testing; Physics, Applied SC Materials Science; Physics GA BP29Z UT WOS:000084618600107 ER PT B AU Clausen, B Bourke, MAM AF Clausen, B Bourke, MAM BE Liaw, PK Arsenault, RJ Green, RE Murty, KL Thompson, RB TI Microstructural stress strain inhomogeneity in MMCs SO NONDESTRUCTIVE EVALUATION (NDE) AND MATERIAL PROPERTIES IV LA English DT Proceedings Paper CT Symposium on Nondestructive Evaluation (NDE) and Material Properties IV, at the 1999 TMS Annual Meeting CY FEB 28-MAR 04, 1999 CL SAN DIEGO, CA SP Minerals Met & Mat Soc ID DIFFRACTION MEASUREMENTS; INTERNAL-STRESSES; DEFORMATION; COMPOSITE AB Even though most engineering materials are regarded isotropic on a macroscopic scale, the elastic and plastic anisotropy in the grains results in inhomogeneities on a microstructural level. Furthermore, the constraints provided by a composite tends to effect not only the overall trends, but also the microstructural anisotropy of the constituent phases. Even though neutron diffraction measurements have previously been used to verify finite element calculations of mean phase strains in composite materials, these continuum mechanic finite element models can not provide information at the microstructural level. By using a self-consistent polycrystal deformation model it is possible to calculate the elastic lattice strains in the grains of a polycrystal for direct comparison with the neutron diffraction measurements. Measured and predicted results for different MMC systems are presented. C1 Univ Calif Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. RP Clausen, B (reprint author), Univ Calif Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, POB 1663,Mail Stop H805, Los Alamos, NM 87545 USA. RI Clausen, Bjorn/B-3618-2015 OI Clausen, Bjorn/0000-0003-3906-846X NR 11 TC 0 Z9 0 U1 0 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-431-3 PY 1999 BP 15 EP 19 PG 5 WC Materials Science, Characterization & Testing SC Materials Science GA BM94Y UT WOS:000080237100003 ER PT S AU Del Grande, NK Durbin, PF AF Del Grande, NK Durbin, PF BE Chase, SB TI Delamination detection in reinforced concrete using thermal inertia SO NONDESTRUCTIVE EVALUATION OF BRIDGES AND HIGHWAYS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nondestructive Evaluation of Bridges and Highways III CY MAR 03-05, 1999 CL NEWPORT BEACH, CA SP Soc Photo Opt Instrumentat Engineers, Fed Highway Adm, Soc Exptl Mech Inc, Amer Soc Nondestruct Testing, Japanese Soc Nondestruct Testing DE pursed thermal imaging; thermal inertia; detection of concrete bridgedeck delaminations ID INFRARED COMPUTED-TOMOGRAPHY; STRUCTURAL DEFECTS; AIRCRAFT; DAMAGE AB We investigated the feasibility of thermal inertia mapping for bridge deck inspections, Using pulsed thermal imaging, we heat-stimulated surrogate delaminations in reinforced concrete and asphalt-concrete slabs. Using a dual-band infrared camera system, we measured thermal inertia responses of Styrofoam implants under 5 cm of asphalt, 5 cm of concrete, and 10 cm of asphalt rind concrete. We compared thermal maps from solar-heated concrete and asphalt-concrete slabs with thermal inertia maps from flash-heated concrete and asphalt-concrete slabs. Thermal inertia mapping is a toot for visualizing and quantifying subsurface defects. Physically, thermal inertia is a measure of the resistance of the bridge deck to temperature change. Experimentally, it is determined from the inverse slope of the surface temperature: versus the inverse square root of time. Mathematically, thermal inertia is the square root of the product of thermal conductivity, density, and heat capacity. Thermal inertia mapping distinguishes delaminated decks which have below-average thermal inertias from normal or shaded decks. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Del Grande, NK (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,MS L333, Livermore, CA 94550 USA. NR 32 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 0-8194-3057-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3587 BP 186 EP 197 DI 10.1117/12.339924 PG 12 WC Engineering, Civil; Materials Science, Characterization & Testing; Optics SC Engineering; Materials Science; Optics GA BM81Y UT WOS:000079833300019 ER PT S AU Morey, RM AF Morey, RM BE Chase, SB TI Innovative GPR for pavement inspection SO NONDESTRUCTIVE EVALUATION OF BRIDGES AND HIGHWAYS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nondestructive Evaluation of Bridges and Highways III CY MAR 03-05, 1999 CL NEWPORT BEACH, CA SP Soc Photo Opt Instrumentat Engineers, Fed Highway Adm, Soc Exptl Mech Inc, Amer Soc Nondestruct Testing, Japanese Soc Nondestruct Testing DE GPR; pavements; variable pulse-width; inspection; NDE AB A new ground penetrating radar system was built using a controllable variable pulse-width transmitter and a new antenna design. The transmitter generates monocycle pulses with pulse widths that are continuously variable from 0.5 to 2 nanoseconds; thus, the center frequency of the pulse spectrum is variable from 500 to 2000 MHz. The antenna is relatively small and light weight and operates in both the air-coupled and ground-coupled mode. The complete prototype system including radar control unit, antenna unit, lap-top computer, battery, and back-pack, weighs 65 pounds, is portable and easily usable by one person. The software developed for this new GPR includes a menu driven, user-friendly interface for selecting an operating frequency from 500 to 2000 MHz and an automatic data interpretation algorithm. Hardware and software development focused on a GPR system for evaluating pavement systems and to automatically measure pavement thickness. Other GPR applications are readily apparent. A Neural Network was trained to interpret the radar data in real-time and display pavement thickness as the operator is scanning the pavement. Field test results demonstrate that the prototype GPR can measure asphait pavement thinner than 4 cm (at 2000 MHz) and can penetrate sandy soils to depths greater than 5 meters (at 500 MHz). This GPR system replaces other radar pavement-evaluation systems that require multiple antenna/transmitter units to accomplish the same range of measurements. The design concepts embodied here are scalable to other extended frequency ranges, e.g., 50 to 200 MHz for geologic surveys with a single antenna/transmitter unit. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Morey, RM (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-395, Livermore, CA 94551 USA. NR 13 TC 1 Z9 1 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 0-8194-3057-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3587 BP 200 EP 209 DI 10.1117/12.339925 PG 10 WC Engineering, Civil; Materials Science, Characterization & Testing; Optics SC Engineering; Materials Science; Optics GA BM81Y UT WOS:000079833300020 ER PT S AU Bond, LJ AF Bond, LJ BE Reuter, WG TI Predictive engineering for aging infrastructure SO NONDESTRUCTIVE EVALUATION OF UTILITIES AND PIPELINES III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nondestructive Evaluation of Utilities and Pipelines III CY MAR 04, 1999 CL NEWPORT BEACH, CA SP Soc Photo Opt Instrumentat Engineers, Soc Exptl Mech Inc, Amer Soc Nondestruct Testing, Japanese Soc Nondestruct Inspect DE predictive engineering; NDE; aging; infrastructure; health monitoring ID DAMAGE AB This paper presents an overview of the emerging field of predictive engineering. This is an integrated approach to life-cycle analysis, system monitoring, and management and usable-life prediction that is built on life assessment methodologies, measurements, data analysis and the application of predictive models applied to critical structures and systems. The science and technology that is now becoming predictive engineering has been developing over a period of nearly 30 years. Research is currently in progress to develop predictive engineering for application to critical defense infrastructure and systems, including units in the national conventional munitions stockpile, and to extend its application to elements in the critical national infrastructure. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Bond, LJ (reprint author), Pacific NW Natl Lab, MS K5-25, Richland, WA 99352 USA. NR 53 TC 9 Z9 9 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 0-8194-3058-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3588 BP 2 EP 13 DI 10.1117/12.339938 PG 12 WC Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BM81Z UT WOS:000079833500001 ER PT S AU Nosochkov, Y Corbett, J AF Nosochkov, Y Corbett, J BE Chattopadhyay, S Cornacchia, M Pellegrini, C TI Dynamic aperture studies for SPEAR 3 SO NONLINEAR AND COLLECTIVE PHENOMENA IN BEAM PHYSICS 1998 WORKSHOP SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th ICFA Beam Dynamics Workshop on Nonlinear and Collective Phenomena in Beam Physics CY SEP 01-05, 1998 CL ARCIDOSSO, ITALY SP Int Comm Future Accelerators, US DOP, Univ California Los Angeles, Stanford Linear Accelerator Ctr, Frascati Natl Lab-INFN, Italy, Lawrence Berkeley Natl Lab, KEK Lab, Japan AB The Stanford Synchrotron Radiation Laboratory is investigating an accelerator upgrade project that would replace the present 130 nm . rad FODO lattice with an 18 nm . rad double bend achromat (DBA) lattice: SPEAR 3. The low emittance design yields a high brightness beam, but the stronger focusing in the DBA lattice increases chromaticity and beam sensitivity to machine errors. To ensure efficient injection and long Touschek lifetime, an optimization of the design lattice and dynamic aperture has been performed. In this paper, we review the methods used to maximize the SPEAR 3 dynamic aperture including necessary optics modifications, choice of tune and phase advance, optimization of sextupole and coupling correction, and modeling effects of machine errors, wigglers and lattice periodicity. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Nosochkov, Y (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 15 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 1-56396-862-2 J9 AIP CONF PROC PY 1999 VL 468 BP 25 EP 47 PG 23 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BM95E UT WOS:000080238200004 ER PT S AU Decking, W Robin, D AF Decking, W Robin, D BE Chattopadhyay, S Cornacchia, M Pellegrini, C TI Momentum aperture of the advanced light source SO NONLINEAR AND COLLECTIVE PHENOMENA IN BEAM PHYSICS 1998 WORKSHOP SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th ICFA Beam Dynamics Workshop on Nonlinear and Collective Phenomena in Beam Physics CY SEP 01-05, 1998 CL ARCIDOSSO, ITALY SP Int Comm Future Accelerators, US DOP, Univ California Los Angeles, Stanford Linear Accelerator Ctr, Frascati Natl Lab-INFN, Italy, Lawrence Berkeley Natl Lab, KEK Lab, Japan AB This paper shows measurements of the momentum aperture of the Advanced Light Source (ALS) based on Touschek lifetime measurements. The measured data is compared with tracking simulations and a simple model for the apertures will help to explain the observed effects. C1 LBNL, Berkeley, CA 94720 USA. RP Decking, W (reprint author), LBNL, Berkeley, CA 94720 USA. NR 6 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-862-2 J9 AIP CONF PROC PY 1999 VL 468 BP 119 EP 128 PG 10 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BM95E UT WOS:000080238200010 ER PT S AU Emma, P Helm, R Nosochkov, Y Pitthan, R Raubenheimer, T Thompson, K Zimmermann, F AF Emma, P Helm, R Nosochkov, Y Pitthan, R Raubenheimer, T Thompson, K Zimmermann, F BE Chattopadhyay, S Cornacchia, M Pellegrini, C TI Nonlinear resonant collimation for future linear colliders SO NONLINEAR AND COLLECTIVE PHENOMENA IN BEAM PHYSICS 1998 WORKSHOP SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th ICFA Beam Dynamics Workshop on Nonlinear and Collective Phenomena in Beam Physics CY SEP 01-05, 1998 CL ARCIDOSSO, ITALY SP Int Comm Future Accelerators, US DOP, Univ California Los Angeles, Stanford Linear Accelerator Ctr, Frascati Natl Lab-INFN, Italy, Lawrence Berkeley Natl Lab, KEK Lab, Japan AB We present a scheme for collimating large amplitude particles in the main linacs of a linear collider, by adding octupoles to the FODO lattice of the linac. With this scheme the requirements on downstream collimation can be greatly reduced or perhaps even eliminated. An analytic estimate of the amplitude at which particles are lost is made by calculating the separatrix of the fourth order resonance, and is in good agreement with the results of simulations. Simulations of particle distributions in the beam core and halo are presented, as well as alignment tolerances for the octupoles. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Emma, P (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, MS 26,POB 4349, Stanford, CA 94309 USA. NR 3 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 1-56396-862-2 J9 AIP CONF PROC PY 1999 VL 468 BP 143 EP 156 PG 14 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BM95E UT WOS:000080238200012 ER PT S AU Lebedev, VA AF Lebedev, VA BE Chattopadhyay, S Cornacchia, M Pellegrini, C TI Amplification of beam acceleration in a plasma by plasma instability SO NONLINEAR AND COLLECTIVE PHENOMENA IN BEAM PHYSICS 1998 WORKSHOP SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th ICFA Beam Dynamics Workshop on Nonlinear and Collective Phenomena in Beam Physics CY SEP 01-05, 1998 CL ARCIDOSSO, ITALY SP Int Comm Future Accelerators, US DOP, Univ California Los Angeles, Stanford Linear Accelerator Ctr, Frascati Natl Lab-INFN, Italy, Lawrence Berkeley Natl Lab, KEK Lab, Japan AB Although achieving of high accelerating field in a plasma has been demonstrated experimentally, a practical use of such a scheme for building a large accelerator is questionable. A novel scheme of beam acceleration by a plasma wave is considered in this article. The scheme is based on an initial excitation of a plasma wave by a probe beam with comparatively modest intensity. This seed excitation is then amplified by plasma instability, so that the test beam which follows the probe beam with a small delay will be accelerated by the plasma wave with an amplitude significantly exceeding the initial amplitude of the wave. Because of small interaction between the synchronization beam and the plasma, such a scheme allows one to excite a plasma over large length and, consequently, to build a large accelerator. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Lebedev, VA (reprint author), Jefferson Lab, 12000 Jefferson AVe, Newport News, VA 23606 USA. NR 5 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 1-56396-862-2 J9 AIP CONF PROC PY 1999 VL 468 BP 224 EP 236 PG 13 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BM95E UT WOS:000080238200018 ER PT S AU Ruggiero, AG AF Ruggiero, AG BE Chattopadhyay, S Cornacchia, M Pellegrini, C TI The circular RFQ storage ring SO NONLINEAR AND COLLECTIVE PHENOMENA IN BEAM PHYSICS 1998 WORKSHOP SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th ICFA Beam Dynamics Workshop on Nonlinear and Collective Phenomena in Beam Physics CY SEP 01-05, 1998 CL ARCIDOSSO, ITALY SP Int Comm Future Accelerators, US DOP, Univ California Los Angeles, Stanford Linear Accelerator Ctr, Frascati Natl Lab-INFN, Italy, Lawrence Berkeley Natl Lab, KEK Lab, Japan AB This paper presents a novel idea of storage ring for the accumulation of intense beams of light and heavy ions at low energy. The new concept is a natural development of the combined features used in a conventional storage ring and an ion trap, and is basically a linear RFQ bend on itself. In summary the advantages are: smaller beam dimensions, higher beam intensity, and a more compact storage device. C1 Brookhaven Natl Lab, AGS Dept, Upton, NY 11973 USA. RP Ruggiero, AG (reprint author), Brookhaven Natl Lab, AGS Dept, Upton, NY 11973 USA. NR 3 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 1-56396-862-2 J9 AIP CONF PROC PY 1999 VL 468 BP 244 EP 257 PG 14 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BM95E UT WOS:000080238200020 ER PT S AU Ng, KY Lee, SY AF Ng, KY Lee, SY BE Chattopadhyay, S Cornacchia, M Pellegrini, C TI Particle-beam approach to collective instabilities - Application to space-charge dominated beams SO NONLINEAR AND COLLECTIVE PHENOMENA IN BEAM PHYSICS 1998 WORKSHOP SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th ICFA Beam Dynamics Workshop on Nonlinear and Collective Phenomena in Beam Physics CY SEP 01-05, 1998 CL ARCIDOSSO, ITALY SP Int Comm Future Accelerators, US DOP, Univ California Los Angeles, Stanford Linear Accelerator Ctr, Frascati Natl Lab-INFN, Italy, Lawrence Berkeley Natl Lab, KEK Lab, Japan ID SYNCHROTRON MOTION; MODULATION; RESONANCE AB Nonlinear dynamics deals with parametric resonances and diffusion. The phenomena are usually beam-intensity independent and rely on a particle Hamiltonian. Collective instabilities deal with beam coherent motion, where the Vlasov equation is frequently used in conjunction with a beam-intensity dependent Hamiltonian. We address the questions: Are the two descriptions the same? Are collective instabilities the results of encountering parametric resonances whose driving force is intensity dependent? We study here the example of a space-charge dominated beam governed by the Kapchinskij-Vladimirskij (K-V) envelope equation [1]. The stability and instability regions as functions of tune depression and envelope mismatch are compared in the two approaches. The study has been restricted to the simple example of a uniformly focusing channel. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 19 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 1-56396-862-2 J9 AIP CONF PROC PY 1999 VL 468 BP 300 EP 320 PG 21 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BM95E UT WOS:000080238200025 ER PT S AU Stupakov, GV AF Stupakov, GV BE Chattopadhyay, S Cornacchia, M Pellegrini, C TI Effect of centrifugal transverse wakefield for microbunch in bend SO NONLINEAR AND COLLECTIVE PHENOMENA IN BEAM PHYSICS 1998 WORKSHOP SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th ICFA Beam Dynamics Workshop on Nonlinear and Collective Phenomena in Beam Physics CY SEP 01-05, 1998 CL ARCIDOSSO, ITALY SP Int Comm Future Accelerators, US DOP, Univ California Los Angeles, Stanford Linear Accelerator Ctr, Frascati Natl Lab-INFN, Italy, Lawrence Berkeley Natl Lab, KEK Lab, Japan AB We calculate centrifugal force for a short bunch in vacuum moving in a circular orbit and estimate the emittance growth of the beam in a bend due to this force. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Stupakov, GV (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 14 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 1-56396-862-2 J9 AIP CONF PROC PY 1999 VL 468 BP 334 EP 347 PG 14 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BM95E UT WOS:000080238200027 ER PT S AU Chemla, DS AF Chemla, DS BE Garmire, E Kost, A TI Ultrafast transient nonlinear optical processes in semiconductors SO NONLINEAR OPTICS IN SEMICONDUCTORS I: SEMICONDUCTORS AND SEMIMETALS, VOL. 58 SE Semiconductors and Semimetals LA English DT Review ID GAAS QUANTUM-WELLS; NONCANONICAL-TRANSFORMATION APPROACH; ONE-DIMENSIONAL MAGNETOEXCITONS; PULSE-EXCITED SEMICONDUCTOR; COULOMB BOLTZMANN KINETICS; FEMTOSECOND PHOTON-ECHOES; MONTE-CARLO SIMULATIONS; FERMI-EDGE SINGULARITY; LO-PHONON SCATTERING; ELECTRON-HOLE PLASMA C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA USA. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 190 TC 28 Z9 28 U1 1 U2 9 PU ELSEVIER ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 0080-8784 BN 0-12-752167-4 J9 SEMICONDUCT SEMIMET JI Semicond. Sdemimet. PY 1999 VL 58 BP 175 EP 256 PG 82 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BM59S UT WOS:000079198100003 ER PT B AU Huston, MA AF Huston, MA BE AguirreBravo, C Franco, CR TI Forest productivity and diversity: Using ecological theory and landscape models to guide sustainable forest management SO NORTH AMERICAN SCIENCE SYMPOSIUM: TOWARD A UNIFIED FRAMEWORK FOR INVENTORYING AND MONITORING FOREST ECOSYSTEM RESOURCES SE USDA FOREST SERVICE ROCKY MOUNTAIN RESEARCH STATION PROCEEDINGS LA English DT Proceedings Paper CT North American Science Symposium on Toward a Unified Framework for Inventorying and Monitoring Forest Ecosystem Resources CY NOV 01-06, 1998 CL GUADALAJARA, MEXICO SP USDA, Forest Serv, Inst Nacl Investigac Forestales & Agropecuarias, Natl Pk Serv, Univ Autonoma Guadalajara, Long Term Ecol Res, USDA, Gobierno Estado Jalisco, Canadian Forest Serv, Environm Canada, EMCO, Nat Resources Canada, US Dept Interior Geol Survey, SEMARNAP, SAGAR INIFAP ID SPECIES RICHNESS; COMPUTER-MODEL; BOREAL FORESTS; SOIL-MOISTURE; LIFE-HISTORY; SUCCESSION; DYNAMICS; VEGETATION; PATTERN; GROWTH AB Sustainable forest management requires maintaining or increasing ecosystem productivity, while preserving or restoring natural levels of biodiversity. Application of general concepts from ecological theory, along with use of mechanistic, landscape-based computer models, can contribute to the successful achievement of both of these objectives. Ecological theories based on the energetics and dynamics of populations can be used to predict the general distribution of individual species, the diversity of different types of species, ecosystem process rates and pool sizes, and patterns of spatial and temporal heterogeneity over a broad range of environmental conditions. This approach requires subdivision of total biodiversity into "functional types" of organisms, primarily because different types of organisms respond very differently to the spatial and temporal variation of environmental conditions on landscapes. The diversity of species of the same functional type (particularly among plants) tends to be highest at relatively low levels of net primary productivity, while the total number of different functional types (particularly among animals) tends to be highest at high levels of productivity (e.g., site index or potential net primary productivity). In general, the diversity of animals at higher trophic levels (e.g., predators) reaches its maximum at much higher levels of productivity than the diversity of lower trophic levels (e.g., plants). This means that a single environment cannot support high diversity of all types of organisms. Within the framework of the general patterns described above, the distributions, population dynamics, and diversity of organisms in specific regions can be predicted more precisely using a combination of computer simulation models and GIS data based on satellite information and ground surveys. Biophysical models that use information on soil properties, climate, and hydrology have been developed to predict how the abundance and spatial distribution of various plants and animals. These models can be used to predict the patterns of forest type and structure that develop in response to variation in productivity and disturbance across complex landscapes, as well as species diversity and the distribution and population fluctuations of threatened species in specific regions. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Huston, MA (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. EM mhu@ornl.gov RI Huston, Michael/B-1434-2009 OI Huston, Michael/0000-0001-9513-1166 NR 87 TC 6 Z9 6 U1 0 U2 2 PU US DEPT AGR, FOREST SERV ROCKY MT FOREST & RANGE EXPTL STN PI FT COLLINS PA FT COLLINS, CO 80526 USA J9 US FOR SERV RMRS-P JI USDA For. Ser. Rocky Mt. Res. Stat. Proc. PY 1999 IS 12 BP 329 EP 341 PG 13 WC Ecology; Environmental Sciences; Forestry SC Environmental Sciences & Ecology; Forestry GA BP77R UT WOS:000086142400057 ER PT S AU Kitayama, M Glaeser, AM AF Kitayama, M Glaeser, AM BE Suzuki, H Komeya, K Uematsu, K TI The energetics and kinetics of pore shape changes in alumina SO NOVEL SYNTHESIS AND PROCESSING OF CERAMICS SE KEY ENGINEERING MATERIALS LA English DT Article; Proceedings Paper CT International Symposium on Novel Synthesis and Processing of Ceramics CY OCT 26-29, 1997 CL KURUME, JAPAN SP JSPS 124th Comm High Tempuratur Ceram Mat, Organizing Comm, Japan Soc Promot Sci, Ceram Soc Japan, Chem Soc Japan, Kyushu Bur Int Trade & Ind, Kyushu Natl Ind Res Ind, Fukuoka Prefecture, Saga Prefecture, Kurume City, Kurume Inst Technol, Kurume Chamber Commerce & Ind, Fdn Kyushu Ind Technol Ctr, Fukuoka Ind Sci & Technol Fdn, Technopolis Fdn Kurume Tosu, Kurume Res Park Co Ltd, Asahi Glass Fdn, Nippon Sheet Glass Fdn Mat Sci & Engn, Ishikawa Fdn Carbon Sci & Technol, Kurume Ind Technol Adv Fdn, Kurume City Tourism & Convent Bur, Kurume Int Exchange Assoc, Kyushu Fine Ceram Technoforum DE alumina; surface energy; Wulff shape; surface diffusion; surface attachment limited kinetics (SALK) ID PERIODIC SURFACE PROFILES; ION-IMPLANTED SAPPHIRE; CRACK-LIKE FLAWS; MORPHOLOGICAL EVOLUTION; VICINAL SURFACES; FREE-ENERGY; DIFFUSION; PARTICLES; DECAY AB Microlithography and ion beam etching were used to introduce controlled size cavities into the surfaces of undoped sapphire substrates of controlled (and varied) surface orientation. These cavities were converted into internal intragranular pores by diffusion bonding of the etched substrate to an unetched substrate. Two studies were performed. In the first, arrays of cavities as small as approximate to 2 mu m x 2 mu m wide and approximate to 0.37 mu m deep were introduced, annealed for prolonged periods at 1600 degrees and 1800 degrees C, and the equilibrium cavity shape was determined using scanning electron and atomic force microscopy. By measuring the pore shape precisely, and indexing the facets that form, the relative surface energies of different low index surfaces were determined using the Wulff construction. In the second study, wider (approximate to 20 mu m x 20 mu m) but similarly shallow (approximate to 0.5 mu m) intragranular pores were produced, and pore shape changes during high temperature annealing (1900 degrees C) were examined. A model based on surface diffusion controlled evolution was developed, and the predictions of the model were compared to the experimentally observed pore morphology changes. Evolution rates were found to vary widely among the substrates, despite an initially identical pore geometry. The most dramatic differences appear to reflect the stability of the surface into which the pores are etched, i.e., the substrate orientation. A more detailed assessment of the results suggests that surface attachment limited kinetics (SALK) play an important role in determining the rate of surface mass transport on the examined low index surfaces of alumina. C1 Fine Ceram Res Assoc, Synergy Ceram Lab, Kita Ku, Nagoya, Aichi 462, Japan. 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 Kitayama, M (reprint author), Fine Ceram Res Assoc, Synergy Ceram Lab, Kita Ku, 1-1 Hirate Cho, Nagoya, Aichi 462, Japan. NR 37 TC 6 Z9 6 U1 0 U2 3 PU TRANS TECH PUBLICATIONS PI CLAUSTHAL ZELLERFE PA EINERSBERGER BLICK 28, PO BOX 266, W-3392 CLAUSTHAL ZELLERFE, GERMANY SN 1013-9826 BN 0-87849-814-1 J9 KEY ENG MAT PY 1999 VL 159-1 BP 193 EP 204 PG 12 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BN11G UT WOS:000080750000029 ER PT S AU Thomas, G Gopal, M AF Thomas, G Gopal, M BE Suzuki, H Komeya, K Uematsu, K TI Electron microscopy and microanalysis of advanced ceramics SO NOVEL SYNTHESIS AND PROCESSING OF CERAMICS SE KEY ENGINEERING MATERIALS LA English DT Article; Proceedings Paper CT International Symposium on Novel Synthesis and Processing of Ceramics CY OCT 26-29, 1997 CL KURUME, JAPAN SP JSPS 124th Comm High Tempuratur Ceram Mat, Organizing Comm, Japan Soc Promot Sci, Ceram Soc Japan, Chem Soc Japan, Kyushu Bur Int Trade & Ind, Kyushu Natl Ind Res Ind, Fukuoka Prefecture, Saga Prefecture, Kurume City, Kurume Inst Technol, Kurume Chamber Commerce & Ind, Fdn Kyushu Ind Technol Ctr, Fukuoka Ind Sci & Technol Fdn, Technopolis Fdn Kurume Tosu, Kurume Res Park Co Ltd, Asahi Glass Fdn, Nippon Sheet Glass Fdn Mat Sci & Engn, Ishikawa Fdn Carbon Sci & Technol, Kurume Ind Technol Adv Fdn, Kurume City Tourism & Convent Bur, Kurume Int Exchange Assoc, Kyushu Fine Ceram Technoforum DE ceramics; interface; joining; composite; electron microscopy ID SILICON-NITRIDE CERAMICS; RARE-EARTH-OXIDES; FRACTURE-TOUGHNESS; OXIDATION; BEHAVIOR; KINETICS; CREEP; MICROSTRUCTURE; COMPOSITES; STRENGTH AB In order to successfully achieve microstructural tailoring of materials for desired properties, it is necessary to understand processing-structure-property linkages in great detail. This requires the characterization of advanced materials by sophisticated techniques, especially those of advanced electron microscopy, diffraction and microanalysis. Microstructurally, grain boundaries and interfaces play dominant roles in the performance of ceramics, but their characterization poses particularly difficult problems. However, progress in high resolution imaging and microanalytical techniques, especially energy loss spectroscopy, are proving to be essential to understand many problems, including defects introduced in processing. This paper summarizes examples from our research dealing with refractory ceramics based on Si3N4, including joining, and BN-coated SiC-fiber reinforced SIC composites. 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 Thomas, G (reprint author), Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. NR 34 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 0-87849-814-1 J9 KEY ENG MAT PY 1999 VL 159-1 BP 235 EP 243 PG 9 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BN11G UT WOS:000080750000035 ER PT S AU Nakashima, K Makino, T Mori, K Glaeser, AM AF Nakashima, K Makino, T Mori, K Glaeser, AM BE Suzuki, H Komeya, K Uematsu, K TI Wettability and interfacial reaction between Si3N4 and Cu-based alloys SO NOVEL SYNTHESIS AND PROCESSING OF CERAMICS SE KEY ENGINEERING MATERIALS LA English DT Article; Proceedings Paper CT International Symposium on Novel Synthesis and Processing of Ceramics CY OCT 26-29, 1997 CL KURUME, JAPAN SP JSPS 124th Comm High Tempuratur Ceram Mat, Organizing Comm, Japan Soc Promot Sci, Ceram Soc Japan, Chem Soc Japan, Kyushu Bur Int Trade & Ind, Kyushu Natl Ind Res Ind, Fukuoka Prefecture, Saga Prefecture, Kurume City, Kurume Inst Technol, Kurume Chamber Commerce & Ind, Fdn Kyushu Ind Technol Ctr, Fukuoka Ind Sci & Technol Fdn, Technopolis Fdn Kurume Tosu, Kurume Res Park Co Ltd, Asahi Glass Fdn, Nippon Sheet Glass Fdn Mat Sci & Engn, Ishikawa Fdn Carbon Sci & Technol, Kurume Ind Technol Adv Fdn, Kurume City Tourism & Convent Bur, Kurume Int Exchange Assoc, Kyushu Fine Ceram Technoforum DE wettability; interfacial reaction; Si3N4; Cu-based alloy; joining ID CERAMICS AB The effect of additions on the wetting characteristics of liquid Cu on a Si3N4 substrate has been studied in parallel with the study of joining of Si3N4 using Cu/80Ni . 20Cr/Cu interlayers. The addition of 80Ni . 20Cr alloy and Cr reduced the contact angle of liquid Cu on a Si3N4 substrate. The contact angle reduction depended upon the Cr content of the sessile drop and anneal time. A multiphase reaction layer developed at the interface between the Cu-rich solidified droplet and Si3N4 when Cr or 80Ni . 20Cr was added. The failure of Cu/80Ni . 20Cr/Cu interlayer bonded Si3N4 occurred along the Si3N4/interlayer interface. At near the Si3N4/interlayer interface, a multiphase reaction layer has also developed. The strengths of bonded Si3N4 are strongly affected by the interfacial reaction products. C1 Kyushu Univ, Fac Engn, Dept Mat Sci & Engn, Fukuoka 812, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. RP Nakashima, K (reprint author), Kyushu Univ, Fac Engn, Dept Mat Sci & Engn, Fukuoka 812, Japan. NR 8 TC 1 Z9 1 U1 1 U2 2 PU TRANS TECH PUBLICATIONS PI CLAUSTHAL ZELLERFE PA EINERSBERGER BLICK 28, PO BOX 266, W-3392 CLAUSTHAL ZELLERFE, GERMANY SN 1013-9826 BN 0-87849-814-1 J9 KEY ENG MAT PY 1999 VL 159-1 BP 287 EP 292 PG 6 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BN11G UT WOS:000080750000043 ER PT J AU Giruzzi, G Zabiego, M Gianakon, TA Garbet, X Cardinali, A Bernabei, S AF Giruzzi, G Zabiego, M Gianakon, TA Garbet, X Cardinali, A Bernabei, S TI Dynamical modelling of tearing mode stabilization by RF current drive SO NUCLEAR FUSION LA English DT Article ID ELECTRON-CYCLOTRON WAVES; NONLINEAR DYNAMICS; MAGNETIC ISLANDS; ASDEX UPGRADE; TOKAMAK; PLASMAS; MHD; PERTURBATIONS; CONFINEMENT; SUPPRESSION AB The theory of tearing mode stabilization in toroidal plasmas by RF driven currents that are modulated in phase with the island rotation is investigated, A time-scale analysis of the phenomena involved indicates that transient effects, such as finite time response of the driven currents, island rotation during the power pulses and the inductive response of the plasma, are intrinsically important. A dynamical model of such effects is developed, based on a 3-D Fokker-Planck code coupled to both the electric field diffusion equation and the island evolution equation. Extensive applications to both ECCD and LHCD in ITER are presented. C1 CEA Cadarache, EURATOM Assoc, CEA Fus, Dept Rech Fus Controlee, St Paul Les Durance, France. EURATOM, ENEA Fus, Ctr Ric Energia Frascati, Frascati, Italy. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Giruzzi, G (reprint author), CEA Cadarache, EURATOM Assoc, CEA Fus, Dept Rech Fus Controlee, St Paul Les Durance, France. NR 52 TC 67 Z9 67 U1 3 U2 19 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD JAN PY 1999 VL 39 IS 1 BP 107 EP 125 DI 10.1088/0029-5515/39/1/307 PG 19 WC Physics, Fluids & Plasmas SC Physics GA 192TP UT WOS:000080095700007 ER PT J AU Zhang, SY Weng, WT AF Zhang, SY Weng, WT TI Beam loading effect in bunch leakage at the PSR SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE beam loading; storage rings; bunch leakage; space charge; instability AB In this article, the effects of longitudinal space charge and beam loading are discussed for the PSR bunch leakage, which can be an important factor in the e-p instability encountered there. It is shown that for the parameters we use for the PSR operations, the beam loading effect without compensation can result in significant beam leakage, in presence of the space charge effect. Increasing the RF voltage, or reducing the Linac beam chopping rate, call reduce the leakage. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, AGS Dept, Upton, NY 11973 USA. RP Zhang, SY (reprint author), Brookhaven Natl Lab, AGS Dept, 911B, Upton, NY 11973 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 1 PY 1999 VL 420 IS 1-2 BP 12 EP 19 DI 10.1016/S0168-9002(98)00907-3 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 149WP UT WOS:000077629500003 ER PT J AU Thevuthasan, S Peden, CHF Engelhard, MH Baer, DR Herman, GS Jiang, W Liang, Y Weber, WJ AF Thevuthasan, S Peden, CHF Engelhard, MH Baer, DR Herman, GS Jiang, W Liang, Y Weber, WJ TI The ion beam materials analysis laboratory at the environmental molecular sciences laboratory SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE ion beam materials; environmental molecular sciences laboratory (EMSL); Rutherford backscattering spectrometry (RBS) AB The Environmental Molecular Sciences Laboratory (EMSL), a Department of Energy (DOE) collaborative scientific user facility located at Pacific Northwest National Laboratory (PNNL), is completing an accelerator facility dedicated to ion beam modification and analysis of materials. This facility consists of a new 3.4 MV tandem accelerator from National Electrostatic Corporation (NEC), two ion sources including an Alphatross source and a SNICS sputter source, and three beam lines. One of the beam lines ( + 30 degrees beam line) is dedicated to ultrahigh vacuum (UHV) materials analysis. The end station at this beam line has high-energy ion scattering capabilities including Rutherford backscattering spectrometry (RBS), channeling, nuclear reaction analysis (NRA), and elastic recoil detection analysis (ERDA), as well as electron spectroscopies such as low-energy electron diffraction (LEED) and Auger electron spectroscopy (AES). This end station is interfaced with the EMSL sample transfer capability which allows a sample to be synthesized, processed, and characterized in different surface science instruments at EMSL without exposing the sample to air. A commercial high vacuum RC43 end station from NEC has capabilities for RES, NRA, ERDA, particle induced X-ray and gamma emission (PIXE and PIGE), and is located at the end of the -15 degrees beam line. A custom high vacuum end station is connected to the +15 degrees beam line and is dedicated to ion implantation. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Thevuthasan, S (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999,MSIN K2-12, Richland, WA 99352 USA. RI Engelhard, Mark/F-1317-2010; Weber, William/A-4177-2008; Baer, Donald/J-6191-2013; OI Weber, William/0000-0002-9017-7365; Baer, Donald/0000-0003-0875-5961; Peden, Charles/0000-0001-6754-9928; Jiang, Weilin/0000-0001-8302-8313; Engelhard, Mark/0000-0002-5543-0812 NR 13 TC 59 Z9 60 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 1 PY 1999 VL 420 IS 1-2 BP 81 EP 89 DI 10.1016/S0168-9002(98)00908-5 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 149WP UT WOS:000077629500009 ER PT J AU Barlow, RJ Bernet, R Bowdery, CK Brose, J Champion, T Dahlinger, G Dauncey, P Eckstein, P Eigen, G Freytag, D Fry, J Geddes, NI Hertzbach, SS Ivanchenko, V Jessop, C Johnson, D King, M Lorenz, E Marsiske, H McMahon, S Nicholson, H Reidy, J Schindler, R Schubert, KR Schwierz, R Scott, I Seitz, R Silagadze, Z Spaan, B Stoker, DP Tetteh-Lartey, E Waldi, R Wisniewski, WJ Wuest, CR AF Barlow, RJ Bernet, R Bowdery, CK Brose, J Champion, T Dahlinger, G Dauncey, P Eckstein, P Eigen, G Freytag, D Fry, J Geddes, NI Hertzbach, SS Ivanchenko, V Jessop, C Johnson, D King, M Lorenz, E Marsiske, H McMahon, S Nicholson, H Reidy, J Schindler, R Schubert, KR Schwierz, R Scott, I Seitz, R Silagadze, Z Spaan, B Stoker, DP Tetteh-Lartey, E Waldi, R Wisniewski, WJ Wuest, CR TI Results from the BABAR electromagnetic calorimeter beam test SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE BABAR; electrons; pions AB We present results from the PSI test beam run for the electromagnetic calorimeter of the BABAR experiment. A system of 25 CsI(T1) crystals was tested with electrons and pions in the momentum range from 100 to 405 MeV/c. Results are presented on crystal light output, on coherent and incoherent noise, on energy resolution and on spatial resolution. The design energy resolutions of the Technical Design Report of BABAR were achieved. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Tech Univ Dresden, D-8027 Dresden, Germany. Univ Manchester, Manchester, Lancs, England. Univ Edinburgh, Edinburgh, Midlothian, Scotland. Univ Lancaster, Lancaster, England. Brunel Univ, London, England. Univ Liverpool, Liverpool L69 3BX, Merseyside, England. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Bergen, Bergen, Norway. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA USA. Univ Massachusetts, Amherst, MA 01003 USA. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Univ London Royal Holloway & Bedford New Coll, Surrey, England. Max Planck Inst Phys, D-80805 Munich, Germany. Mt Holyoke Coll, S Hadley, MA 01075 USA. Univ Mississippi, Oxford, MS USA. Univ Calif Irvine, Irvine, CA 92717 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Waldi, R (reprint author), Tech Univ Dresden, D-8027 Dresden, Germany. RI Silagadze, Zurab/K-8970-2013; OI Barlow, Roger/0000-0002-8295-8612 NR 16 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 1 PY 1999 VL 420 IS 1-2 BP 162 EP 180 DI 10.1016/S0168-9002(98)01167-X PG 19 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 149WP UT WOS:000077629500016 ER PT J AU Ringo, MC Huhta, MS Shea-McCarthy, G Penner-Hahn, JE Evans, CE AF Ringo, MC Huhta, MS Shea-McCarthy, G Penner-Hahn, JE Evans, CE TI On-line X-ray fluorescence detection for capillary electrophoresis separations SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article AB In these investigations, capillary electrophoresis with on-line X-ray fluorescence detection (CE-XRF) has been demonstrated for the first time. The insertion of a polyethylene sample cell between fused-silica capillary segments enabled continuous XRF detection during electrophoresis with minimal additional band broadening. Detection limits in the 10(-4) M range are currently feasible for the CE-XRF separation of metal complexes, and design advances will enhance detectability to the 10(-5)-10(-6) M range, permitting studies of important environmental and biological samples. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Michigan, Dept Chem, Ann Arbor, MI 48109 USA. Brookhaven Natl Lab, Univ Chicago, Consortium Adv Radiat Sources, Upton, NY 11973 USA. RP Evans, CE (reprint author), Univ Michigan, Dept Chem, 930 N Univ Av, Ann Arbor, MI 48109 USA. NR 10 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 149 IS 1-2 BP 177 EP 181 DI 10.1016/S0168-583X(98)00889-1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166HT UT WOS:000078570700024 ER PT J AU Marrs, RE AF Marrs, RE TI Self-cooling of highly charged ions during extraction from electron beam ion sources and traps SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE ion source; ion trap; evaporative cooling; EBIT; EBIS ID URANIUM IONS; LOSSES AB Evaporative self-cooling can produce a dramatic reduction in the temperature and emittance of ions extracted from electron beam ion sources and traps for favorable values of ion density and charge if the trapping potential is removed slowly. For existing electron beam ion traps, calculations predict that 20% of trapped Ar18+ ions can be extracted with an average emittance 30 times lower than the uncooled emittance. It may be possible to construct sources of very-highly charged ions with an absolute brightness of order 2x10(10) ions/mm(2) mrad(2) s, a value more than four orders of magnitude larger than that of existing highly charged ion sources. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Marrs, RE (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808-050, Livermore, CA 94551 USA. NR 25 TC 23 Z9 23 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 149 IS 1-2 BP 182 EP 194 DI 10.1016/S0168-583X(98)00624-7 PG 13 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166HT UT WOS:000078570700025 ER PT J AU Monteiro, OR AF Monteiro, OR TI Plasma synthesis of hard materials with energetic ions SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE filtered cathodic arc deposition; diamondlike carbon films; plasma deposition ID IMPLANTATION; DEPOSITION AB Recent developments in plasma synthesis of hard materials using metal plasma immersion ion implantation and deposition are described. We have produced and characterized a variety of films including doped and undoped DLC (diamond-like carbon) and metal carbides. By using multiple plasma sources operated either synchronously or asynchronously. different metal plasma species can be either blended or linked so as to form mixed-composition films or multilayer structures, and by control of the depositing ion energy, interfaces can be made sharp or graded and the film morphology and microstructure can be widely tailored. Plasma compositional uniformity is important to produce homogeneous films. and therefore effective mixing of plasma streams produced by the filtered cathodic vacuum arcs is very important. Specific systems described here include amorphic diamond, and TIG. We outline the deposition technique employed in this investigation, and summarize the results of the characterization of the films. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Monteiro, OR (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Mail Stop 53-0004, Berkeley, CA 94720 USA. NR 18 TC 27 Z9 27 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 12 EP 16 DI 10.1016/S0168-583X(98)00685-5 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700003 ER PT J AU Mitsuishi, K Song, M Furuya, K Birtcher, RC Allen, CW Donnelly, SE AF Mitsuishi, K Song, M Furuya, K Birtcher, RC Allen, CW Donnelly, SE TI Observation of atomic processes in Xe nanocrystals embedded in Al under 1 MeV electron irradiation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE HRTEM; Xe; precipitate; dislocation; stacking fault ID ALUMINUM; BUBBLES AB Defect introduction processes in two differently sized Xe nanocrystals embedded in Al were observed with in situ high-resolution electron microscopy. The imaging conditions made it possible to follow the apparent movement of Xe atom columns within a nanocrystal. The positions of individual atom columns were measured on captured video images, before and after defect introduction, from intensity traces along the rows of atom columns. For each of these precipitates, a planar defect appears on {1 1 1 }. The observed displacement of Xe atom columns approximately corresponds to the projected displacement produced by a Shockley partial dislocation, bounding an intrinsic stacking fault. Comparison of the displacements of atoms in the two nanocrystals shows that the displacements are reduced at the precipitate/matrix interfaces. This implies that there will be a displacement at interfaces that represents some compromise between the strain field of the partial dislocation and the interface compatibility requirement. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Natl Res Inst Met, Tsukuba, Ibaraki 3050003, Japan. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Salford, Dept Phys, Salford M5 4WT, Lancs, England. RP Mitsuishi, K (reprint author), Natl Res Inst Met, 3-13 Sakura, Tsukuba, Ibaraki 3050003, Japan. NR 8 TC 11 Z9 13 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 184 EP 188 DI 10.1016/S0168-583X(98)00705-8 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700033 ER PT J AU Birtcher, RC Donnelly, SE AF Birtcher, RC Donnelly, SE TI Plastic flow produced by single ion impacts on metals SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST ID GOLD AB Single ion impacts have been observed using in situ transmission electron microscopy and video recording with a time resolution of 33 ms. Gold was irradiated at 50 K and room temperature. Single ion impacts produce holes, modify existing holes, and extrude material into the initial specimen hole and holes formed by other ion impacts. The same behavior is observed at both temperatures. At both temperatures, ion impacts result in craters and ejected material. Ion impacts produce more small craters than large ones for all ion masses, while heavier mass ions produce more and larger craters than lighter mass ions. This comparison is affected by the ion energy. As the energy of an ion is increased, the probability for deposition near the surface decreases and fewer craters are formed. For a given ion mass, crater production depends on the probability for displacement cascade production in the near surface region. Craters and holes are stable at room temperature, however, ion impacts near an existing crater may cause flow of material into the crater either reshaping or annihilating it, Holes and craters result from the explosive outflow of material from the molten zone of near-surface cascades. The outflow may take the form of molten material. a solid lid or an ejected particle. The surface is a major perturbation on displacement cascades resulting from ion impacts. Published by Elsevier Science B.V. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Salford, Joule Phys Lab, Salford M5 4WT, Lancs, England. RP Birtcher, RC (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Donnelly, Stephen/0000-0002-9749-5550 NR 8 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 194 EP 199 DI 10.1016/S0168-583X(98)00822-2 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700035 ER PT J AU Misra, A Fayeulle, S Kung, H Mitchell, TE Nastasi, M AF Misra, A Fayeulle, S Kung, H Mitchell, TE Nastasi, M TI Residual stresses and ion implantation effects in Cr thin films SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE residual stress; Cr thin films; ion irradiation ID IRRADIATION; RELAXATION AB The evolution of intrinsic residual stresses in sputtered Cr thin films with substrate bias and post-deposition ion irradiation is investigated. The relaxation of tensile stresses and build up of compressive stresses with increasing ion irradiation dose is studied using ions of different masses and energies such as 110 keV Ar, 33 keV C and 330 keV Xe. The stress evolution is related to the corresponding microstructural changes in the films. The changes in the residual stress during ion irradiation are explained by considering the manner in which the interatomic distances and forces change during irradiation, and the generation of defects during irradiation. (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 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 16 TC 42 Z9 43 U1 1 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 211 EP 215 DI 10.1016/S0168-583X(98)00780-0 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700037 ER PT J AU Lee, DH Fayeulle, S Walter, KC Nastasi, M AF Lee, DH Fayeulle, S Walter, KC Nastasi, M TI Internal stress reduction in diamond like carbon thin films by ion irradiation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE diamondlike carbon; plasma processing; ion irradiation; stress ID TETRAHEDRAL AMORPHOUS-CARBON; PLASTIC-FLOW; SILICON AB The stress-state of diamond like carbon (DLC) film was monitored in situ during Xe. Ar, Ne, and C irradiation. All irradiations were observed to produce a reduction in the as-deposited compressive stress. We have modeled the irradiation induced stress reduction in DLC by considering the different bond states of carbon that are possible in these materials, i.e. sp(2) and sp(3). An Avrami-Johnson-Mehl analysis of irradiation induced transformation indicates that at low doses the transformation occurs in one-dimensional-like volumes associated with non-overlapping collision cascades. As the irradiation dose increases, a full transformation occurs at the peak in the irradiation damage profile. With further increasing dose, the transformation product spreads out from the peak damage region. The rate of stress change is well correlated with the displacement damage produced in the collision cascade at a low dose linear region of sigma-phi curves. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Lee, DH (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS K762, Los Alamos, NM 87545 USA. NR 22 TC 21 Z9 21 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 216 EP 220 DI 10.1016/S0168-583X(98)00739-3 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700038 ER PT J AU Fayeulle, S Misra, A Kung, H Nastasi, M AF Fayeulle, S Misra, A Kung, H Nastasi, M TI Thermal annealing, irradiation, and stress in multilayers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE thermal annealing; irradiation; stress; multilayers ID C-N MULTILAYERS; ION IRRADIATION; FILMS; INTERDIFFUSION; BOMBARDMENT; RELAXATION; REDUCTION AB The evolution of the microstructure of a TiN/B-C-N multilayered thin film during thermal annealing and irradiation has been studied by low angle X-ray diffraction and transmission electron microscopy, Stress has been determined by curvature measurements. After deposition, TIN is crystalline while B-C-N is amorphous. Thermal anneals in vacuum at 600-1000 degrees C lead to an increase of the bilayer repeat length and to a phase separation at the interfaces. After the 600 degrees C annealing, ion irradiation (Ar ions: 300 keV 1x10(15) ions/cm(2)?) causes an additional increase of the bilayer repeat length but a decrease of the quality of the interface. After annealing at 800 degrees C or 1000 degrees C, the irradiation causes a major decrease of the bilayer repeat length (more than 20% after annealing at 1000 degrees C and irradiation). The stress is highly compressive after deposition (sigma = -2000 MPa). After the 600 degrees C annealing, the stress is totally relaxed (sigma = 0) and becomes tensile after annealing at higher temperatures (sigma = + 1200 MPa after 800 degrees C annealing, sigma = + 1500 MPa after 1000 degrees C annealing), TEM confirms the decrease of the bilayer repeat length after an irradiation of the samples subjected to high temperature anneal and reveal an increase of the roughness of the interfaces. These phenomena are discussed in terms of stress driven diffusion during irradiation. (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 Nastasi, M (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RI Misra, Amit/H-1087-2012 NR 23 TC 5 Z9 5 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 227 EP 231 DI 10.1016/S0168-583X(98)00774-5 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700040 ER PT J AU Ishimaru, M Tsunemori, T Harada, S Arita, M Motooka, T AF Ishimaru, M Tsunemori, T Harada, S Arita, M Motooka, T TI Microstructural evolution of oxygen implanted silicon during annealing processes SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE silicon-on-insulator structure; EELS; TEM; XPS ID BURIED OXIDE; LAYERS AB Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and electron energy loss spectroscopy (EELS) have been employed to characterize the microstructures, oxygen distributions, and chemical bonding states of SIMOX (Separation by IMplanted OXygen) wafers. Silicon substrates were implanted at 550 degrees C with 2x10(17) and 4x10(17) cm(-2) 180 keV oxygen ions, followed by annealing at various temperatures. EELS spectra indicated that the chemical bonding state between Si and oxygen changed at 1000 degrees C anneal, though there was no appreciable change in the microstructures observed by TEM below 1000 degrees C anneal. Above 1100 degrees C, oxygen precipitates were preferentially formed around the peak positions of the detect and oxygen concentrations in the as-implanted samples. These precipitates aggregated to reduce the surface energy, and their size increased with temperature. After 1350 degrees C anneal. a continuous buried oxide layer was formed in the higher-dose specimen, while the upper- and lower-precipitates remained separately in the lower-dose one. The XPS profiles did not change at the later stage of annealing processes in the 2x10(17) cm(-2) sample, though the precipitates became larger in size. This suggests that the oxygen diffusion mostly occurs along the lateral direction but does not along the vertical one in this sample (C) 1999 Elsevier Science B.V. All rights reserved. C1 Kyushu Univ, Dept Mat Sci & Engn, Fukuoka 8128581, Japan. RP Los Alamos Natl Lab, Div Mat Sci & Technol, Mail Stop G755, Los Alamos, NM 87545 USA. EM ishimaru@zaiko.kyushu-u.ac.jp NR 8 TC 15 Z9 15 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X EI 1872-9584 J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 311 EP 316 DI 10.1016/S0168-583X(98)00773-3 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700056 ER PT J AU Myers, SM Han, J Headley, TJ Hills, CR Petersen, GA Seager, CH Wampler, WR AF Myers, SM Han, J Headley, TJ Hills, CR Petersen, GA Seager, CH Wampler, WR TI Ion-implanted hydrogen in gallium nitride SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE gallium nitride; hydrogen; ion implantation; bubbles; defects ID POLARITY; GAN AB Hydrogen was ion-implanted into wurtzite-phase GaN, and its transport, bound states, and microstructural effects during annealing up to 980 degrees C were investigated by nuclear-reaction profiling, ion-channeling analysis, transmission electron microscopy, and infrared (IR) spectroscopy. At implanted concentrations greater than or similar to 1 at.%, faceted H-2 bubbles formed enabling identification of preferred surfaces, examination of passivating N-H states on these surfaces, and determination of the diffusivity-solubility product of the H. At concentrations below the threshold of bubble formation. H states characterized by N-H bonding and coherence with the host lattice were observed by IR spectroscopy and ion channeling. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Dept 1112, Albuquerque, NM 87185 USA. RP Myers, SM (reprint author), Sandia Natl Labs, Dept 1112, Mailstop 1056,POB 5800, Albuquerque, NM 87185 USA. NR 8 TC 3 Z9 3 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 386 EP 390 DI 10.1016/S0168-583X(98)00695-8 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700070 ER PT J AU Ridgway, MC Glover, CJ Bezakova, E Byrne, AP Foran, GJ Yu, KM AF Ridgway, MC Glover, CJ Bezakova, E Byrne, AP Foran, GJ Yu, KM TI Atomic-level characterisation of ion-induced amorphisation in compound semiconductors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE GaAs; InP; extended X-ray absorption fine structure; perturbed angular correlation; ion implantation; defect characterisation ID ELECTRIC-FIELD GRADIENT; DEFECTS; GALLIUM AB Two microscopic analytical techniques, extended X-ray absorption fine structure (EXAFS) and perturbed angular correlation (PAC), have been utilised to characterise ion-induced amorphisation in compound semiconductors at the atomic scale. The structural parameters of stoichiometric, amorphised GaAs were determined from EXAFS measurements. Relative to a crystalline sample, the nearest-neighbor bond length and Debye-Waller factor both increased for amorphous material. In contrast, the coordination numbers about both Ga and As constituent atoms in the amorphous phase decreased to similar to 3.85 atoms from the crystalline value of 4. All measured parameters were independent of implant conditions and were thus considered indicative of the intrinsic, amorphous phase as opposed to an extrinsic, implantation-induced structure. Furthermore, the heterogeneous amorphisation of InP was quantified with PAC measurements. Dose-dependent crystalline, disordered and amorphous environments of the In-111 probes were established and a direct amorphisation process was identified. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Australian Natl Univ, Res Sch Phys Sci & Engn, Canberra, ACT, Australia. Australian Nucl Sci & Technol Org, Canberra, ACT, Australia. Lawrence Livermore Natl Lab, Div Sci Mat, Livermore, CA USA. RP Ridgway, MC (reprint author), Univ Paris 11, CNRS, CSNSM, IN2P3,Bat 108,Orsay Campus, F-91405 Orsay, France. EM mcr109@rsphysse.anu.edu.au RI Ridgway, Mark/D-9626-2011; Yu, Kin Man/J-1399-2012; OI Ridgway, Mark/0000-0002-0642-0108; Yu, Kin Man/0000-0003-1350-9642; Byrne, Aidan/0000-0002-7096-6455 NR 10 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 391 EP 395 DI 10.1016/S0168-583X(98)00766-6 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700071 ER PT J AU Gerlach, JW Schrupp, D Volz, K Zeitler, M Rauschenbach, B Anders, A AF Gerlach, JW Schrupp, D Volz, K Zeitler, M Rauschenbach, B Anders, A TI Low-energy ion assisted deposition of epitaxial gallium nitride films SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE gallium nitride; ion assisted deposition; constricted glow discharge plasma source; X-ray dole figures; channeling-RBS ID GROWTH; GAN; MBE AB Epitaxial gallium nitride thin films were grown on c-plane and r-plane sapphire: by low-energy ion assisted deposition in high vacuum using a constricted glow discharge plasma sourer for the supply of nitrogen. Instead of preparing a conventional low-temperature buffer layer, a single-temperature process with initial growth rate ramp was performed. The crystallographic structure and texture, defect distribution, morphology and topography of the grown films were investigated with X-ray diffraction techniques, channeling-RBS, TEM and AFM, respectively. The ion assisted growth procedure results in well-oriented, epitaxial, single crystalline, wurtzitic GaN films with low defect densities. The film surfaces are generally smooth, but show either holes or clusters indicating unbalanced gallium and nitrogen fluxes during growth. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Augsburg, Inst Phys, Lehrstuhl Expt Phys 4, D-86135 Augsburg, Germany. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Gerlach, JW (reprint author), Univ Augsburg, Inst Phys, Lehrstuhl Expt Phys 4, D-86135 Augsburg, Germany. RI Anders, Andre/B-8580-2009 OI Anders, Andre/0000-0002-5313-6505 NR 10 TC 8 Z9 8 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 406 EP 410 DI 10.1016/S0168-583X(98)00681-8 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700074 ER PT J AU Papanicolaou, N Rao, MV Molnar, B Tucker, J Edwards, A Holland, OW Ridgway, MC AF Papanicolaou, N Rao, MV Molnar, B Tucker, J Edwards, A Holland, OW Ridgway, MC TI Ion-implantation in SiC and GaN SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE SiC; GaN; implantation; annealing; activation ID PHOSPHORUS AB The electrical activation behavior of N- and Al-implantations in bulk V-doped semi-insulating 4H-SiC is similar to that in 4H-SiC epitaxial layers. The As- and Sb-implantations in p-type 6H-SiC epitaxial layers showed out-diffusion behavior with room-temperature sheet carrier concentrations of <20% of the implanted dose. In n-type GaN, compensating levels introduced by the high-dose implantation damage are thermally stable even at 1150 degrees C annealing. (C) 1999 Elsevier Science B.V. All rights reserved. C1 George Mason Univ, Dept Elect & Comp Engn, Fairfax, VA 22030 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Australian Natl Univ, Dept Elect Mat Engn, Canberra, ACT, Australia. USN, Res Lab, Washington, DC 20375 USA. RP Papanicolaou, N (reprint author), George Mason Univ, Dept Elect & Comp Engn, Fairfax, VA 22030 USA. RI Ridgway, Mark/D-9626-2011 OI Ridgway, Mark/0000-0002-0642-0108 NR 15 TC 4 Z9 4 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 416 EP 420 DI 10.1016/S0168-583X(98)00880-5 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700076 ER PT J AU Jiang, W Weber, WJ Thevuthasan, S McCready, DE AF Jiang, W Weber, WJ Thevuthasan, S McCready, DE TI Displacement energy measurements for ion-irradiated 6H-SiC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE 6H-SiC; ion irradiation; displacement energy; RBS/channeling AB Single crystal 6H-SiC wafers were separately irradiated at 180 or 190 K with energetic He+, C+ and Si+ ion beams to doses ranging from 0.008 to 0.42 dpa, with corresponding damage levels ranging from isolated point defects to complete amorphization. The accumulation of disorder on the Si sublattice has been followed using in-situ RES measurements along the (0 0 0 1)-axial channeling direction. In conjunction with SRIM-97 simulations and the Kinchin-Pease approximation, the average displacement energy for the Si sublattice at each dose has been estimated from the damage profile and integrated disorder concentration. At low defect concentrations, these energies approach the threshold displacement energy for perfect crystals. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Jiang, W (reprint author), Pacific NW Lab, POB 999,MS K8-93,902 Battelle Blvd, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 14 TC 20 Z9 20 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 557 EP 561 DI 10.1016/S0168-583X(98)00717-4 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700104 ER PT J AU Jiang, W Weber, WJ Thevuthasan, S McCready, DE AF Jiang, W Weber, WJ Thevuthasan, S McCready, DE TI Damage formation and recovery in C+-irradiated 6H-SIC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE 6H-SiC; ion irradiation; defect annealing; RBS/channeling ID INDUCED AMORPHIZATION; ION IRRADIATION; SILICON-CARBIDE; RECRYSTALLIZATION; TEMPERATURE; CRYSTALLINE; CERAMICS AB Single crystals of 6H-SiC were irradiated with 550 keV C+ ions over a range of temperatures (180 -870 K) and ion fluences (1 x 10(18) to 5 x 10(19) C+/m(2)). The damage induced by the irradiation ranged from dilute defect concentrations up to buried amorphous layers. Damage recovery in the samples irradiated at 180 K; has been followed by isochronal annealing (20 min) at 300, 370, 670 and 870 K(. The accumulation and recovery of atomic disorder on the Si sublattice has been studied using in situ Rutherford Backscattering Spectrometry in combination with ion channeling methods (RBS/C). The disordering rate shows a sigmoidal dependence on dose at each irradiation temperature. Simultaneous defect recovery processes occur during irradiation at room temperature, and post-irradiation thermal defect recovery is also observed at room temperature. Published by Elsevier Science B.V. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Jiang, W (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 15 TC 13 Z9 13 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 562 EP 566 DI 10.1016/S0168-583X(98)00716-2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700105 ER PT J AU Afanasyev-Charkin, IV Gritsyna, VT Cooke, DW Bennett, BL Evans, CR Hollander, MG Sickafus, KE AF Afanasyev-Charkin, IV Gritsyna, VT Cooke, DW Bennett, BL Evans, CR Hollander, MG Sickafus, KE TI Optical absorption and thermoluminescence of MgAl2O4 spinel crystals implanted with Xe++ ions SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE spinel; MgAl2O4; F-centers; amorphization; optical absorption; thermoluminescence ID ALUMINATE SPINEL; AL2O3 AB We have studied changes in optical absorption of MgAl2O4 spinel crystals implanted with 340 keV Xe++ ions at about 120 K, to fluences ranging from 10(15)-10(21) ions/m(2). With increasing ion fluence, we observe an increase in optical absorption, especially in the vicinity of two absorption bands: one centered at 5.3 eV. the other at 6.9 eV. The absorption band at 5.3 eV, caused by F-centers, saturates at a fluence between 1.10(18) and 1.10(19) ions/m(2). This is the same dose range in which formation of a metastable phase of spinel has been reported previously. The band at 6.9 eV grows with increasing dose and saturates at 1.10(20) -3.10(20) ions/m(2). Previous studies have shown that spinel is amorphized by Xe ion irradiation in this dose range. Annealing studies were also conducted on the Xe ion implanted spinel crystals. By optical absorption, F-centers were found to anneal at 500 degrees C. Thermoluminescence measurements revealed a temperature dependence of luminescence that correlates well with the optical absorption. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Kharkov State Univ, UA-310077 Kharkov, Ukraine. Univ Calif Los Alamos Natl Lab, Div MST 8, Los Alamos, NM 87545 USA. RP Afanasyev-Charkin, IV (reprint author), Kharkov State Univ, UA-310077 Kharkov, Ukraine. NR 12 TC 12 Z9 15 U1 3 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 787 EP 792 DI 10.1016/S0168-583X(98)00854-4 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700148 ER PT J AU Meldrum, A White, CW Boatner, LA Anderson, IM Zuhr, RA Sonder, E Budai, JD Henderson, DO AF Meldrum, A White, CW Boatner, LA Anderson, IM Zuhr, RA Sonder, E Budai, JD Henderson, DO TI Microstructure of sulfide nanocrystals formed by ion-implantation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE nanocrystals; sulfides; ion implantation; ZnS; CdS; PbS AB Ion implantation is a versatile tool for the formation of compound semiconductor nanocrystal precipitates in a host medium with the ultimate goal of producing a uniform size distribution of quantum dots for use in optical devices. Ion implantation was used to form ZnS, CdS, and PbS nanocrystals in both glass and crystalline hosts, and the precipitate microstructures and size distributions were investigated by TEM techniques. The size distributions were found to be significantly different for the three compounds, and several unusual microstructures were observed. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Fisk Univ, Dept Phys, Nashville, TN 37203 USA. RP Meldrum, A (reprint author), Oak Ridge Natl Lab, Div Solid State, MS-6057, Oak Ridge, TN 37831 USA. RI Boatner, Lynn/I-6428-2013; Budai, John/R-9276-2016 OI Boatner, Lynn/0000-0002-0235-7594; Budai, John/0000-0002-7444-1306 NR 6 TC 42 Z9 42 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 957 EP 963 DI 10.1016/S0168-583X(98)00727-7 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700179 ER PT J AU White, CW Meldrum, A Budai, JD Withrow, SP Sonder, E Zuhr, RA Hembree, DM Wu, M Henderson, DO AF White, CW Meldrum, A Budai, JD Withrow, SP Sonder, E Zuhr, RA Hembree, DM Wu, M Henderson, DO TI Formation of CdS and CdSe nanocrystals by sequential implantation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE CdS nanocrystals; CdSe nanocrystals; sequential ion implantation ID OPTICAL-PROPERTIES; SIZE; GLASS; GROWTH AB Nanocrystals of CdS and CdSe have been formed in SiO2, Al2O3, and Si by sequential ion implantation and annealing. In SiO2, the nanocrystals have the hexagonal wurtzite structure and are randomly oriented. In Al2O3 and Si, nanocrystals are three dimensionally oriented. They have the cubic zincblende structure in Si and can be produced with either structure in Al2O3 by controlling the implantation conditions. In SiO2 and Al2O3 nanocrystals exhibit strong optical absorption and photoluminescence (PL). Evidence for quantum confinement is observed, and the PL results for CdSe are strongly temperature dependent. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Oak Ridge Y12 Plant, Oak Ridge, TN USA. Fisk Univ, Nashville, TN 37203 USA. RP White, CW (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 14 TC 27 Z9 27 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 991 EP 996 DI 10.1016/S0168-583X(98)00683-1 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700185 ER PT J AU Ila, D Williams, EK Smith, CC Poker, DB Hensley, DK Klatt, C Kalbitzer, S AF Ila, D Williams, EK Smith, CC Poker, DB Hensley, DK Klatt, C Kalbitzer, S TI Post-implantation bombardment assisted formation of colloidal Au in silica SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE ion implantation; silica; nanocluster; radiation effects; optical properties ID MEV ION-IMPLANTATION; FUSED-SILICA; GLASS AB In this work. we demonstrate that by post-implantation bombardment of 2.0 MeV Au-implanted suprasil by MeV heavy ions such as silicon, one can assist the formation of Au nanoclusters. We will also demonstrate the relationship between the energy deposited in electronic excitations by the MeV Si ions in the Au-implanted layer with the size of these nanoclusters as well as with the optical absorption band due to formation of Au nanoclusters. The optical absorption band characteristic of the Au-implanted suprasil as well as the TEM results were used to monitor the formation of the metallic clusters before and after post-implantation bombardment. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Alabama A&M Univ, Dept Phys, Ctr Irradiat Mat, Normal, AL 35762 USA. Oak Ridge Natl Lab, Div Solid State, Redstone Arsenal, AL 35898 USA. Max Planck Inst Kernphys, D-69029 Heidelberg, Germany. RP Ila, D (reprint author), Alabama A&M Univ, Dept Phys, Ctr Irradiat Mat, POB 1447, Normal, AL 35762 USA. RI Hensley, Dale/A-6282-2016 OI Hensley, Dale/0000-0001-8763-7765 NR 10 TC 9 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 1012 EP 1016 DI 10.1016/S0168-583X(98)00759-9 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700189 ER PT J AU Johnson, E Johansen, A Sarholt, L Dahmen, U AF Johnson, E Johansen, A Sarholt, L Dahmen, U TI Nanosized lead inclusions in silicon produced by ion implantation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE lead nanoinclusions; silicon; ion implantation; channeling AB Silicon single crystals have been implanted with 80 keV lead ions to a concentration of about 3 at.%. TEM and RBS/channeling analysis showed that implantations at 300 and 625 K induced amorphization of the implanted layer with nanoscale lead inclusions embedded in the amorphous matrix. At 300 K; the lead inclusions had sizes around 1-2 nm and showed no clear signs of crystallinity. At 625 K the inclusions with size around 5 nm had a distinct fee structure and were oriented randomly in the amorphous matrix. Implantations at 925 K retained the crystalline nature of the matrix and the implanted layer contained faceted fee lead inclusions about 10 nm in size growing in parallel-cube alignment with the matrix. Annealing of the samples implanted at 300 and 625 K, respectively, for one hour at 1175 K led to recrystallization of the amorphous matrix with simultaneous loss of nearly all the implanted lead, while about 80% of the implanted lead was retained after annealing of samples implanted at 925 K. (C) 1999 Elsevier Science B.V. All rights reserved. C1 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), Niels Bohr Inst, Orsted Lab, Univ Pk 5, DK-2100 Copenhagen O, Denmark. NR 15 TC 20 Z9 21 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 1034 EP 1038 DI 10.1016/S0168-583X(98)00821-0 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700193 ER PT J AU Zimmerman, RL Ila, D Williams, EK Poker, DB Hensley, DK Klatt, C Kalbitzer, S AF Zimmerman, RL Ila, D Williams, EK Poker, DB Hensley, DK Klatt, C Kalbitzer, S TI Ion beam synthesis of Au and Cu nanoclusters in MgO SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE nanoclusters; implantation; optical materials ID SILVER AB Implantation of 2 MeV ions of An or Cu into single crystals of MgO (100) at room temperature results in the spontaneous formation of metallic nanoclusters for implantation fluences above a threshold value. The formation and growth of these clusters may be induced by post implantation bombardment with silicon ions which stop beyond the implantation layer, as well as by thermal annealing. We have compared spontaneous nanocluster formation, ion bombardment induced cluster formation and post thermal annealing. The size and number of nanoclusters were studied by optical absorption spectroscopy and using the Mie and Doyle theories which relate the optical absorption bands to the formation of nanoclusters. The post bombardment of the gold implanted samples was made with 1.2, 2.0 and 5.0 MeV silicon ions. The depth and distribution of the gold and silicon were observed using RES. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Alabama A&M Univ, Ctr Irradiat Mat, Normal, AL 35762 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Max Planck Inst Kernphys, D-69029 Heidelberg, Germany. RP Zimmerman, RL (reprint author), Alabama A&M Univ, Ctr Irradiat Mat, POB 1447, Normal, AL 35762 USA. EM rlzimm@cim.aamu.edu RI Hensley, Dale/A-6282-2016 OI Hensley, Dale/0000-0001-8763-7765 NR 11 TC 23 Z9 25 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 1064 EP 1068 DI 10.1016/S0168-583X(98)00741-1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700199 ER PT J AU Williams, EK Ila, D Darwish, A Poker, DB Sarkisov, SS Curley, MJ Wang, JC Svetchnikov, VL Zandbergen, HW AF Williams, EK Ila, D Darwish, A Poker, DB Sarkisov, SS Curley, MJ Wang, JC Svetchnikov, VL Zandbergen, HW TI Characterization of silver colloids formed in LiBbO(3) by Ag and O implantation at room and elevated temperatures SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE ion implantation; nanocluster; nonlinear refractive index; z-scan; lithium niobate ID OPTICAL-PROPERTIES; SILICA; GLASS AB To address the issue of dispersion of Ag colloids in LiNbO3 at heat treatment temperatures of 400-500 degrees C, Ap,and O were implanted at energies of 160 and 35 keV, respectively, at room temperature (RT) and at 500 degrees C. Fluences were 4x 10(16) and 8x 10(16)/cm(2) and the order of the Ag and O implants was varied. Electron paramagnetic resonance spectra indicated that only O followed by Ag implantation of 500 degrees C produced silver oxide. Optical absorption spectrometry and RES showed significant differences in the dispersion of the colloids with implant temperature and implant order. Implantation of Ag at 1.5 MeV to a fluence of 2x10(16)/cm(2) followed by heat treatment at 500 degrees C for 1 h produced nonlinear optical waveguides with a nonlinear index of the order of 10(-10) cm(2)/W at 532 nm. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Alabama A&M Univ, Ctr Irradiat Mat, Normal, AL 35762 USA. Alabama A&M Univ, Dept Nat & Phys Sci Phys, Normal, AL 35762 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Delft Univ Technol, Mat Sci Lab, Natl Ctr HREM, NL-2628 AL Delft, Netherlands. Ukrainian Acad Sci, Inst Met Phys, Dept Supercond, UA-252142 Kiev, Ukraine. RP Williams, EK (reprint author), Alabama A&M Univ, Ctr Irradiat Mat, POB 1447, Normal, AL 35762 USA. NR 14 TC 16 Z9 16 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 1074 EP 1078 DI 10.1016/S0168-583X(98)00758-7 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700201 ER PT J AU Iskanderova, ZA Kleiman, JI Gudimenko, Y Tkachenko, A Tennyson, RC Brown, IG Monteiro, OR AF Iskanderova, ZA Kleiman, JI Gudimenko, Y Tkachenko, A Tennyson, RC Brown, IG Monteiro, OR TI Metal ion implantation and dynamic ion mixing for the protection of high-performance polymers from severe oxidative environment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE plasma immersion ion implantation; polymers; oxidation resistance AB Low energy high-dose Plasma Immersion Ion Implantation. combining both ion and recoil implantation (dynamic ion mixing). was used to enrich thin surface layers of high-performance polymers with an appropriate amount of specially selected reactive metal element such as Al. Both oxygen plasma and fast (E similar to 2-3 eV) atomic oxygen (FAO) beam have been used as aggressive environments for testing the implanted polymers. The modified materials successfully survived these test environments, including FAG, which is the main danger for carbon-based materials in space, in low Earth orbit. The retained doses of implanted and recoil implanted elements were controlled by RES. The content, structure and morphology of the modified protective surface layers were examined by XPS and scanning electron microscopy (SEM). It was shown that protective oxide(s)-based surface structures were formed. Implantation and conversion conditions were found for which the appearance and important thermo-optical properties of treated polymer films, such as solar absorptance and thermal emittance. were practically unchanged. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Integr Testing Lab, Toronto, ON M3H 5T6, Canada. Univ Toronto, Inst Aerosp Studies, Toronto, ON M3H 5T6, Canada. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Iskanderova, ZA (reprint author), Integr Testing Lab, 4925 Dufferin St, Toronto, ON M3H 5T6, Canada. EM ziskand@utias.utoronto.ca NR 22 TC 20 Z9 20 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 1090 EP 1096 DI 10.1016/S0168-583X(98)00797-6 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700204 ER PT J AU Evelyn, AL Ila, D Zimmerman, RL Bhat, K Poker, DB Hensley, DK Klatt, C Kalbitzer, S Just, N Drevet, C AF Evelyn, AL Ila, D Zimmerman, RL Bhat, K Poker, DB Hensley, DK Klatt, C Kalbitzer, S Just, N Drevet, C TI Ion beam modification of PES, PS and PVC polymers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 11th International Conference on Ion Beam Modification of Materials (IBMM98) CY AUG 31-SEP 04, 1998 CL ROYAL TROP INST, AMSTERDAM, NETHERLANDS HO ROYAL TROP INST DE polymers; ion beams; thin films; cross linking ID PHENOLFORMALDEHYDE; RESIN AB MeV ions passing through polymer films modify their electrical and optical properties and these changes are related to changes in the chemical structures of the polymers. The effects of certain cross linking enhancers, such as sulfur and other pendant molecules, on the ion beam modification process were investigated. Stacked, thin films of polyethersulfone, polyvinyl chloride and polystyrene were bombarded with MeV helium ions and the induced changes in the chemical structure of the polymers were studied with Raman microprobe analysis and RES combined with in situ residual gas analysis. FTIR spectroscopy was used to categorize the changes in the optical properties. The results were then compared with those from previously studied polyethylene and polyvinylidene chloride polymers. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Alabama A&M Univ, Dept Nat & Phys Sci, Ctr Irradiat Mat, Normal, AL 35762 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN USA. Max Planck Inst Kernphys, D-69029 Heidelberg, Germany. Univ Lyon 1, F-69622 Villeurbanne, France. RP Evelyn, AL (reprint author), Alabama A&M Univ, Dept Nat & Phys Sci, Ctr Irradiat Mat, POB 1447, Normal, AL 35762 USA. RI Hensley, Dale/A-6282-2016 OI Hensley, Dale/0000-0001-8763-7765 NR 10 TC 25 Z9 25 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 148 IS 1-4 BP 1141 EP 1145 DI 10.1016/S0168-583X(98)00858-1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 166KT UT WOS:000078575700214 ER PT J AU Ridgway, MC Glover, CJ Foran, GJ Yu, KM AF Ridgway, MC Glover, CJ Foran, GJ Yu, KM TI Atomic-level characterisation of the structure of amorphised GaAs utilising EXAFS measurements SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT Symposium J on Ion Implantation into Semiconductors, Oxides and Ceramics, at the Spring Meeting of the European-Materials-Research-Society CY JUN 16-19, 1998 CL STRASBOURG, FRANCE SP European Mat Res Soc DE GaAs; amorphous GaAs; extended X-ray absorption fine structure; EXAFS; ion implantation ID AMORPHOUS GALLIUM-ARSENIDE; BINDING MOLECULAR-DYNAMICS; ABSORPTION FINE-STRUCTURE; SEMICONDUCTORS; DEFECTS AB Extended X-ray absorption fine structure (EXAFS) analysis has been used to determine the structural parameters of stoichiometric, amorphised GaAs. Relative to a crystalline sample, the nearest-neighbor bond length and Debye-Waller factor both increased for amorphous material. In contrast, the coordination numbers about both Ga and As atoms in the amorphous phase decreased to similar to 3.85 atoms from the crystalline value of four. Similar trends were evident for amorphised Ge excluding the coordination number which did not deviate from the crystalline value. The structural parameters of amorphised GaAs and Ge have been discussed in terms of the multi- and mono-elemental nature, respectively, of the two materials. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Australian Natl Univ, Res Sch Phys Sci & Engn, Dept Elect Mat Engn, Canberra, ACT, Australia. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Ridgway, MC (reprint author), Ctr Spectrometrie Nucl & Spectrometrie Masse, CNRS, IN2P3, Bat 108 Orsay Campus, F-91405 Orsay, France. EM mcr109@rsphysse.anu.edu.au RI Yu, Kin Man/J-1399-2012; Ridgway, Mark/D-9626-2011 OI Yu, Kin Man/0000-0003-1350-9642; Ridgway, Mark/0000-0002-0642-0108 NR 14 TC 4 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 147 IS 1-4 BP 148 EP 154 DI 10.1016/S0168-583X(98)00588-6 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 153RK UT WOS:000077846200027 ER PT J AU Pearton, SJ Abernathy, CR Wilson, RG Zavada, JM Song, CY Weinstein, MG Stavola, M Han, J Shul, RJ AF Pearton, SJ Abernathy, CR Wilson, RG Zavada, JM Song, CY Weinstein, MG Stavola, M Han, J Shul, RJ TI Effects of hydrogen implantation into GaN SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT Symposium J on Ion Implantation into Semiconductors, Oxides and Ceramics, at the Spring Meeting of the European-Materials-Research-Society CY JUN 16-19, 1998 CL STRASBOURG, FRANCE SP European Mat Res Soc DE hydrogen; GaN; compensation; device isolation; defects ID MG; REACTIVATION; PASSIVATION; ACCEPTORS; COMPLEX; FILMS AB Proton implantation in GaN is found to reduce the free carrier density through two mechanisms - first, by creating electron and hole traps at around E-C - 0.8 eV and E-V + 0.9 eV that lead to compensation in both n- and p-type material, and second, by leading to formation of (AH)degrees complexes, where A is any acceptor (Mg, Ca, Zn, Be, Cd). The former mechanism is useful in creating high resistivity regions for device isolation, whereas the latter produces unintentional acceptor passivation that is detrimental to device performance. The strong affinity of hydrogen for accepters leads to markedly different redistribution behavior for implanted H+ in n- and p-GaN due to the chemical reaction to form neutral complexes in the latter. The accepters may be reactivated by simple annealing at greater than or equal to 600 degrees C, or by electron injection at 25-150 degrees C that produces debonding of the (AH)degrees centers. Implanted hydrogen is also strongly attracted to regions of strain in heterostructure samples during annealing, leading to pile-up at epi-epi and epi-substrate interfaces. IR spectroscopy shows that implanted hydrogen also decorates V-Ga defects in undoped and n-GaN, (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. USA, Res Off, Res Triangle Pk, NC 27709 USA. Lehigh Univ, Dept Phys, Bethlehem, PA 18015 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Pearton, SJ (reprint author), Univ Florida, Dept Mat Sci & Engn, Rhines Hall,POB 116400, Gainesville, FL 32611 USA. NR 29 TC 13 Z9 14 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 147 IS 1-4 BP 171 EP 174 DI 10.1016/S0168-583X(98)90561-4 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 153RK UT WOS:000077846200030 ER PT J AU Strobel, M Heinig, KH Moller, W Meldrum, A Zhou, DS White, CW Zuhr, RA AF Strobel, M Heinig, KH Moller, W Meldrum, A Zhou, DS White, CW Zuhr, RA TI Ion beam synthesis of gold nanoclusters in SiO2: Computer simulations versus experiments SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT Symposium J on Ion Implantation into Semiconductors, Oxides and Ceramics, at the Spring Meeting of the European-Materials-Research-Society CY JUN 16-19, 1998 CL STRASBOURG, FRANCE SP European Mat Res Soc DE ion beam synthesis; metallic nanoclusters; homogeneous nucleation; kinetic lattice Monte-Carlo method ID FUSED-SILICA; IMPLANTATION AB A kinetic 3D lattice Monte-Carlo (KLMC) method is applied to describe nucleation and growth of nanoclusters from a space- and time-dependent supersaturated solid solution of impurity atoms formed by high-dose ion implantation. Within the framework of homogeneous nucleation, the dependence of the nanocluster size distribution on implantation temperature T-imp and ion current j is shown. The simulation results are consistent with size and depth distributions of gold nanoclusters in SiO2 observed after implantation at different T-imp. The influence of changes of T-imp or j during implantation on the size distribution is simulated and the results are discussed with respect to corresponding implantations. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Rossendorf Inc, Res Ctr, Inst Ion Beam Phys, D-01314 Dresden, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Strobel, M (reprint author), Rossendorf Inc, Res Ctr, Inst Ion Beam Phys, POB 510 119, D-01314 Dresden, Germany. EM strobel@fz-rossendorf.de NR 14 TC 47 Z9 47 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 147 IS 1-4 BP 343 EP 349 DI 10.1016/S0168-583X(98)00541-2 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 153RK UT WOS:000077846200060 ER PT J AU Guha, S Wall, M Chase, LL AF Guha, S Wall, M Chase, LL TI Growth and characterization of Ge nanocrystals SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT Symposium J on Ion Implantation into Semiconductors, Oxides and Ceramics, at the Spring Meeting of the European-Materials-Research-Society CY JUN 16-19, 1998 CL STRASBOURG, FRANCE SP European Mat Res Soc DE Ge nanocrystals; Raman spectroscopy; X-ray; TEM ID POROUS SILICON; LUMINESCENCE; RAMAN; PHOTOLUMINESCENCE; DEFECTS; SIZE AB We have synthesized Ge nanocrystals of mean sizes 4, 8, and 12 nm by ion-implanting Ge+ ions into thermally grown SiO2 films and subsequent annealing of the films at 830 degrees C for 30 min in nitrogen. These films were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Raman spectroscopy. A distribution of particle size was identified by TEM in a 100 nm band below the surface. Particle sizes were estimated by these three techniques. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Condensed Matter & Radiat Sci, Washington, DC 20375 USA. Univ Calif Lawrence Livermore Natl Lab, Div Mat & Chem Sci, Livermore, CA 94550 USA. RP Guha, S (reprint author), USN, Res Lab, Div Condensed Matter & Radiat Sci, Washington, DC 20375 USA. NR 11 TC 21 Z9 22 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JAN PY 1999 VL 147 IS 1-4 BP 367 EP 372 DI 10.1016/S0168-583X(98)00578-3 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 153RK UT WOS:000077846200064 ER PT B AU Jardine, LJ AF Jardine, LJ BE Jardine, LJ Moshkov, MM TI Nuclear materials safety management volume II - Opening remarks SO NUCLEAR MATERIALS SAFETY MANAGEMENT VOL II SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Materials Safety Management CY JUN 08-10, 1998 CL ST PETERSBURG, RUSSIA SP US DOE, Minist Russian Federat Atom Energy, Amarillo Natl Resource Ctr Plutomium C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Jardine, LJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5890-2 J9 NATO SCI S 1 DISARM PY 1999 VL 27 BP 1 EP 2 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BR41E UT WOS:000166321800001 ER PT B AU Lash, TR AF Lash, TR BE Jardine, LJ Moshkov, MM TI US perspectives on nuclear materials safety SO NUCLEAR MATERIALS SAFETY MANAGEMENT VOL II SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Materials Safety Management CY JUN 08-10, 1998 CL ST PETERSBURG, RUSSIA SP US DOE, Minist Russian Federat Atom Energy, Amarillo Natl Resource Ctr Plutomium C1 US DOE, Off Nonproliferat & Natl Secur, Washington, DC 20585 USA. RP Lash, TR (reprint author), US DOE, Off Nonproliferat & Natl Secur, 1000 Independence Ave SW,4B-179, Washington, DC 20585 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5890-2 J9 NATO SCI S 1 DISARM PY 1999 VL 27 BP 9 EP 15 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BR41E UT WOS:000166321800003 ER PT B AU Dodd, LR AF Dodd, LR BE Jardine, LJ Moshkov, MM TI Cooperative efforts to improve the safety of Soviet-designed nuclear power plants SO NUCLEAR MATERIALS SAFETY MANAGEMENT VOL II SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Materials Safety Management CY JUN 08-10, 1998 CL ST PETERSBURG, RUSSIA SP US DOE, Minist Russian Federat Atom Energy, Amarillo Natl Resource Ctr Plutomium C1 Pacific NW Natl Labs, Richland, WA 99352 USA. RP Dodd, LR (reprint author), Pacific NW Natl Labs, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5890-2 J9 NATO SCI S 1 DISARM PY 1999 VL 27 BP 31 EP 42 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BR41E UT WOS:000166321800007 ER PT B AU Ma, CW Jardine, LJ Armantrout, GA AF Ma, CW Jardine, LJ Armantrout, GA BE Jardine, LJ Moshkov, MM TI Safety issues of U. S. ceramic process for excess plutonium immobilization SO NUCLEAR MATERIALS SAFETY MANAGEMENT VOL II SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Materials Safety Management CY JUN 08-10, 1998 CL ST PETERSBURG, RUSSIA SP US DOE, Minist Russian Federat Atom Energy, Amarillo Natl Resource Ctr Plutomium C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Ma, CW (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5890-2 J9 NATO SCI S 1 DISARM PY 1999 VL 27 BP 137 EP 147 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BR41E UT WOS:000166321800019 ER PT B AU Witmer, FE AF Witmer, FE BE Jardine, LJ Moshkov, MM TI US DOE safety knowledge base: Its integration and utilization SO NUCLEAR MATERIALS SAFETY MANAGEMENT VOL II SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Materials Safety Management CY JUN 08-10, 1998 CL ST PETERSBURG, RUSSIA SP US DOE, Minist Russian Federat Atom Energy, Amarillo Natl Resource Ctr Plutomium AB The evolution of the U.S. Department of Energy (DOE) Environmental, Safety and Health (ES&H) information database has tracked the development and growth of personal computers and intra/inter-net capabilities. The scope and applicability of this database, which is primarily electronic, includes DOE's nuclear materials operations and is extremely broad, ranging from ES&H policy/safety initiatives/requirements (Orders) /standards and guides to the recording and analysis of events/accidents and sharing of lessons learned. Much of this information is available to the world via the Internet. Where pertinent, special effort has been made to link to other U.S. government agency ES&H databases. Certain DOE databases (typically preliminary and /or classified) are retained on intranets for appropriate timely access by DOE employees, contractors and/or oversight organizations. Select access to this ES&H database by Minatom could accelerate and enhance the mutual understanding of U.S. and Russian Federation safety cultures. The sharing of lessons learned through the exchange of ES&H databases could result in improvements to both safety cultures. Representative DOE ES&H search engines, database, and build-in analysis capabilities have been surveyed to provide limited "examples" to establish an appreciation for the capabilities and limitations inherent in DOE's major ES&H databases: the Occurrence Reporting and Processing System (ORPS), along with Defense Program's derivative binned information trending tool (DP/ORBITT); the Computerized Accident Incident Reporting System (CAIRS); the Medical Surveillance Program; Performance Measures (PM); and the Lessons Learned (LL) Program. These and other DOE ES&H databases (along with built-in analytical aids) can be overwhelming to the first time user. Each database is specially structured/indexed to facilitate tailored applications, i.e., searching and manipulation within the database proper. Such features present compatibility problems in the consolidation of databases and/or during cross-cut comparisons. Some databases have a "life of their own" because of organizational "stove piping." Typically, time-based trending analysis of types of adverse events/causative factors is too general to identify cause and effect relationships. Without the development of normalized measurements, changes in mission and/or work load affect safety performance far more than do changes associated with the quality of safety management. The use of advanced search engines for unstructured databases to address these deficiencies and to provide the requisite flexibility in dealing with different and changing applications across DOE's ES&H database is under development. C1 US DOE, Germantown, MD 20874 USA. RP Witmer, FE (reprint author), US DOE, DP-21,19901 Germantown Rd, Germantown, MD 20874 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5890-2 J9 NATO SCI S 1 DISARM PY 1999 VL 27 BP 175 EP 188 PG 14 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BR41E UT WOS:000166321800023 ER PT B AU Krumpe, PF AF Krumpe, PF BE Jardine, LJ Moshkov, MM TI Establishing a basis for a United States-Russian Federation multi-year program in nuclear materials safety SO NUCLEAR MATERIALS SAFETY MANAGEMENT VOL II SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Materials Safety Management CY JUN 08-10, 1998 CL ST PETERSBURG, RUSSIA SP US DOE, Minist Russian Federat Atom Energy, Amarillo Natl Resource Ctr Plutomium C1 US DOE, DP, Germantown, MD 20874 USA. RP Krumpe, PF (reprint author), US DOE, DP, 19901 Germantown Rd, Germantown, MD 20874 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5890-2 J9 NATO SCI S 1 DISARM PY 1999 VL 27 BP 189 EP 195 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BR41E UT WOS:000166321800024 ER PT B AU Jardine, LJ AF Jardine, LJ BE Jardine, LJ Moshkov, MM TI The lab-to-institute components - US view SO NUCLEAR MATERIALS SAFETY MANAGEMENT VOL II SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Materials Safety Management CY JUN 08-10, 1998 CL ST PETERSBURG, RUSSIA SP US DOE, Minist Russian Federat Atom Energy, Amarillo Natl Resource Ctr Plutomium C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Jardine, LJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5890-2 J9 NATO SCI S 1 DISARM PY 1999 VL 27 BP 227 EP 231 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BR41E UT WOS:000166321800029 ER PT B AU Ma, CW Jardine, LJ AF Ma, CW Jardine, LJ BE Jardine, LJ Moshkov, MM TI Possible approaches for a Lab-to-Lab program plan SO NUCLEAR MATERIALS SAFETY MANAGEMENT VOL II SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Materials Safety Management CY JUN 08-10, 1998 CL ST PETERSBURG, RUSSIA SP US DOE, Minist Russian Federat Atom Energy, Amarillo Natl Resource Ctr Plutomium C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Ma, CW (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5890-2 J9 NATO SCI S 1 DISARM PY 1999 VL 27 BP 233 EP 238 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BR41E UT WOS:000166321800030 ER PT B AU Young, M Carlson, D AF Young, M Carlson, D BE Jardine, LJ Moshkov, MM TI Approaches to prioritizing the lab-to-lab program SO NUCLEAR MATERIALS SAFETY MANAGEMENT VOL II SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Materials Safety Management CY JUN 08-10, 1998 CL ST PETERSBURG, RUSSIA SP US DOE, Minist Russian Federat Atom Energy, Amarillo Natl Resource Ctr Plutomium C1 Sandia Natl Labs, Albuquerque, NM 87110 USA. RP Young, M (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87110 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5890-2 J9 NATO SCI S 1 DISARM PY 1999 VL 27 BP 239 EP 242 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BR41E UT WOS:000166321800031 ER PT B AU Jardine, LJ Peddicord, KL Moshkov, M Lazarev, LN AF Jardine, LJ Peddicord, KL Moshkov, M Lazarev, LN BE Jardine, LJ Moshkov, MM TI Workshop summary and wrap-up: Panel and participant discussions SO NUCLEAR MATERIALS SAFETY MANAGEMENT VOL II SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Materials Safety Management CY JUN 08-10, 1998 CL ST PETERSBURG, RUSSIA SP US DOE, Minist Russian Federat Atom Energy, Amarillo Natl Resource Ctr Plutomium C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Jardine, LJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5890-2 J9 NATO SCI S 1 DISARM PY 1999 VL 27 BP 243 EP 245 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BR41E UT WOS:000166321800032 ER PT B AU Moretto, LG Beaulieu, L Phair, L Wozniak, GJ AF Moretto, LG Beaulieu, L Phair, L Wozniak, GJ BE Blaizot, JP Campi, X Ploszajczak, M TI The role of statistics and thermodynamics in nuclear multifragmentation SO NUCLEAR MATTER IN DIFFERENT PHASES AND TRANSITIONS SE FUNDAMENTAL THEORIES OF PHYSICS LA English DT Proceedings Paper CT Workshop on Nuclear Matter in Different Phases and Transitions CY MAR 31-APR 10, 1998 CL LES HOUCHES, FRANCE SP Inst Natl Phys Nucl & Phys Particles, CEA, Dept Sci Mat, Delegat Gen Armement, Direct Syst Forces & Prospect, Serv Rech & Etud Armont, Lab SUBATECH, Grand Accelerateur Natl Ions Lourds ID ELEMENTARY BINARY EMISSION; MASS FRAGMENT PRODUCTION; HEAVY-ION COLLISIONS; ARRHENIUS-TYPE PLOTS; TIME-SCALES; REDUCIBILITY; MEV/NUCLEON; DECAY AB The natural limit of binomial reducibility in nuclear multifragmentation is observed in excitation functions for intermediate mass fragments (IMF) of a given element Z. The multiplicity distributions for each window of transverse energy are Poissonian. Thermal scaling is observed in the linear Arrhenius plots constructed from the average multiplicity of each element. "Emission barriers" are extracted from the slopes of the Arrhenius plots and their possible origin is discussed. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Moretto, LG (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 20 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5660-8 J9 FUND THEOR PY 1999 VL 95 BP 43 EP 51 PG 9 WC Physics, Fluids & Plasmas; Physics, Multidisciplinary; Physics, Nuclear; Physics, Particles & Fields SC Physics GA BN99R UT WOS:000083807700004 ER PT B AU Randrup, J AF Randrup, J BE Blaizot, JP Campi, X Ploszajczak, M TI Dynamics of the chiral phase transition SO NUCLEAR MATTER IN DIFFERENT PHASES AND TRANSITIONS SE FUNDAMENTAL THEORIES OF PHYSICS LA English DT Proceedings Paper CT Workshop on Nuclear Matter in Different Phases and Transitions CY MAR 31-APR 10, 1998 CL LES HOUCHES, FRANCE SP Inst Natl Phys Nucl & Phys Particles, CEA, Dept Sci Mat, Delegat Gen Armement, Direct Syst Forces & Prospect, Serv Rech & Etud Armont, Lab SUBATECH, Grand Accelerateur Natl Ions Lourds ID LINEAR SIGMA-MODEL; FINITE-TEMPERATURE; CONDENSATE FORMATION; DCC; BEHAVIOR; DOMAINS; PLASMA C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Randrup, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 34 TC 1 Z9 1 U1 1 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5660-8 J9 FUND THEOR PY 1999 VL 95 BP 107 EP 118 PG 12 WC Physics, Fluids & Plasmas; Physics, Multidisciplinary; Physics, Nuclear; Physics, Particles & Fields SC Physics GA BN99R UT WOS:000083807700009 ER PT J AU Ding, YS Molina, PE Fowler, JS Logan, J Volkow, ND Kuhar, MJ Carroll, FI AF Ding, YS Molina, PE Fowler, JS Logan, J Volkow, ND Kuhar, MJ Carroll, FI TI Comparative studies of epibatidine derivatives [F-18]NFEP and [F-18]N-methyl-NFEP: Kinetics, nicotine effect, and toxicity SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE nicotinic acetylcholine receptors; epibatidine; fluorine-18; PET; nicotine; toxicity ID ACETYLCHOLINE-RECEPTORS; BABOON BRAIN; BINDING; (+/-)-EPIBATIDINE; INHIBITION; INFUSION; INVIVO; PET AB We have previously shown that [F-18]norchlorofluoroepibatidine ([F-18]NFEP) would be an ideal radiotracer for positron emission tomography (PET) imaging of nicotinic acetylcholine receptors (nAChR); however, its high toxicity is a limiting factor for human studies. We, therefore, synthesized its N-methyl derivative ([F-18]N-Me-NFEP) and carried out comparative studies. The distribution volumes for different brain regions were higher for [F-18]N-Me-NFEP than those for [F-18]NFEP (average: 52.5 +/- 0.9 vs. 36.4 +/- 0.7 for thalamus), though the distribution volume (DV) ratios were similar (3.93 +/- 0.27 vs. 3.65 +/- 0.19 for thalamus to cerebellum). Treatment with nicotine reduced the binding of both radiotracers. Toxicology studies in awake rats showed that N-methyl-NFEP has a lower mortality (0 vs. 30%) and smaller effect on plasma catecholamines than NFEP at a dose of 1.5 mu g/kg, However, marked alterations in cardiorespiratory parameters were observed after injection of N-methyl-NFEP (0.5 mu g/kg, IV) to an awake dog, Our results suggest that although the binding characteristics of [F-18]NFEP and [F-18]N-Me-NFEP appear to be ideally suited for PET imaging studies of the human brain, their relatively small safety margin will limit their use in humans. NUCL MED BIOL 26;1:139-148, 1999. (C) 1999 Elsevier Science Inc. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Emory Univ, Atlanta, GA 30322 USA. Res Triangle Inst, Res Triangle Pk, NC 27709 USA. RP Ding, YS (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. EM ding@bnl.gov FU NIDA NIH HHS [DA-06278]; NINDS NIH HHS [NS-15380] NR 38 TC 48 Z9 52 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD JAN PY 1999 VL 26 IS 1 BP 139 EP 148 DI 10.1016/S0969-8051(98)00070-5 PG 10 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 151ZR UT WOS:000077751100021 PM 10096514 ER PT J AU Kennel, SJ Stabin, M Yoriyaz, H Brechbiel, M Mirzadeh, S AF Kennel, SJ Stabin, M Yoriyaz, H Brechbiel, M Mirzadeh, S TI Treatment of lung tumor colonies with Y-90 targeted to blood vessels: Comparison with the alpha-particle emitter Bi-213 SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE lung; tumor; beta-particle emitter; Y-90; Yttrium-90 ID NUDE-MICE; CANCER XENOGRAFTS; BONE-MARROW; RADIOIMMUNOTHERAPY; INVIVO; MODEL; CELLS AB An in vivo lung tumor model system for radioimmunotherapy of lung metastases was used to test the relative effectiveness of the vascular-targeted beta-particle emitter Y-90, and alpha-particle emitter, Bi-213. Yttrium-90 was shown to be stably bound by CHXa" DTPA-MAb 201B conjugates and delivered efficiently to lung tumor blood vessels. Dosimetry calculations indicated that the lung received 16.2 Gy/MBq from treatment with Y-90 MAb 201B, which was a sevenfold greater absorbed dose than any other organ examined. Therapy was optimal for Y-90 with 3 MBq injected. Bismuth-213 MAb 201B also delivered a similar absorbed dose (15Gy/MBq) to the lung. Yttrium-90 was found to be slightly more effective against larger tumors than Bi-213, consistent with the larger range of 2 MeV beta particles from Y-90 than the 8 MeV alpha particles from Bi-213. Treatment of EMT-6 tumors growing in immunodeficient SCID mice with Y-90 or Bi-213 MAb 201 resulted in significant destruction of tumor colonies; however, Y-90 MAb 201B was toxic for the SCID mice, inflicting acute lung damage. In another tumor model, IC-12 rat tracheal carcinoma growing in SCID mouse lungs, Y-90 therapy was more effective than 213Bi at destroying lung tumors. However, Y-90 MAb 201B toxicity for the lung limited any therapeutic effect. We conclude that, although vascular-targeted Y-90 MAb can be an effective therapeutic agent, particularly for larger tumors, in this model system, acute damage to the lung may limit its application. NUCL MED BIOL 26;1:149-157, 1999. (C) 1998 Elsevier Science Inc. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. Oak Ridge Inst Sci & Educ, Div Med Sci, Oak Ridge, TN 37831 USA. IPEN, CN EN SP, Sao Paulo, Brazil. NCI, NIH, DCS, Bethesda, MD 20892 USA. RP Kennel, SJ (reprint author), Oak Ridge Natl Lab, Div Life Sci, Bldg 4500S,MS-6101, Oak Ridge, TN 37831 USA. EM sj9@ornl.gov FU NIAAA NIH HHS [IAA NO. 97-053] NR 32 TC 25 Z9 26 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD JAN PY 1999 VL 26 IS 1 BP 149 EP 157 DI 10.1016/S0969-8051(98)00069-9 PG 9 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 151ZR UT WOS:000077751100022 PM 10096515 ER PT J AU Gattone, AO Abriola, D Avignone, FT Brodzinski, RL Collar, JI Creswick, RJ Di Gregorio, DE Farach, HA Guerard, CK Hasenbalg, F Huck, H Miley, HS Morales, A Morales, J Nussinov, S de Solorzano, AO Reeves, JH Villar, JA Zioutas, K AF Gattone, AO Abriola, D Avignone, FT Brodzinski, RL Collar, JI Creswick, RJ Di Gregorio, DE Farach, HA Guerard, CK Hasenbalg, F Huck, H Miley, HS Morales, A Morales, J Nussinov, S de Solorzano, AO Reeves, JH Villar, JA Zioutas, K CA SOLAX Collaboration TI Experimental search for solar axions. SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 5th International Workshop on Topics in Astroparticle and Underground Physics (TAUP 97) CY SEP 07-11, 1997 CL LAQUILA, ITALY SP Inst Nazl Fisica Nucleare (INFN) ID BRAGG SCATTERING; CP CONSERVATION; PARTICLES AB A new technique has been used to search for solar axions using a single crystal germanium detector. It exploits the coherent conversion of axions into photons when their angle of incidence satisfies a Bragg condition with a crystalline plane. The analysis of approximately 1.94 kg.yr of data from the 1 kg DEMOS detector in Sierra Grande, Argentina, yields anew laboratory bound on axion-photon coupling of g(a gamma gamma) < 2.7 x 10(-9) GeV-1, independent of axion mass up to similar to 1 keV. C1 CNEA, TANDAR Lab, Dept Phys, Buenos Aires, DF, Argentina. Univ S Carolina, Dept Phys, Columbia, SC 29208 USA. Pacific NW Lab, Richland, WA 99352 USA. CERN, CH-1211 Geneva 23, Switzerland. Univ Zaragoza, Lab Fis Nucl & Altas Energias, Zaragoza, Spain. Tel Aviv Univ, Dept Phys, IL-69978 Tel Aviv, Israel. Univ Thessaloniki, Dept Phys, GR-54006 Thessaloniki, Greece. RP CNEA, TANDAR Lab, Dept Phys, Buenos Aires, DF, Argentina. RI Villar, Jose Angel/K-6630-2014 OI Villar, Jose Angel/0000-0003-0228-7589 NR 11 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 70 BP 59 EP 63 DI 10.1016/S0920-5632(98)00388-0 PG 5 WC Physics, Particles & Fields SC Physics GA 122EQ UT WOS:000076059300007 ER PT J AU Akerib, DS Barnes, PD Bauer, DA Brink, PL Cabrera, B Caldwell, DO Clarke, RM Da Silva, A Davies, AK Dougherty, BL Irwin, KD Gaitskell, RJ Golwala, SR Haller, EE Jochum, J Knowlton, WB Kuzminov, V Nam, SW Novikov, V Penn, MJ Perera, TA Ross, RR Sadoulet, B Schnee, RW Shutt, T Smith, A Sonnenschein, AH Spadafora, AL Stockwell, WK Yellin, S Young, BA AF Akerib, DS Barnes, PD Bauer, DA Brink, PL Cabrera, B Caldwell, DO Clarke, RM Da Silva, A Davies, AK Dougherty, BL Irwin, KD Gaitskell, RJ Golwala, SR Haller, EE Jochum, J Knowlton, WB Kuzminov, V Nam, SW Novikov, V Penn, MJ Perera, TA Ross, RR Sadoulet, B Schnee, RW Shutt, T Smith, A Sonnenschein, AH Spadafora, AL Stockwell, WK Yellin, S Young, BA TI Preliminary limits on the WIMP-nucleon cross section from the Cryogenic Dark Matter Search (CDMS) SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 5th International Workshop on Topics in Astroparticle and Underground Physics (TAUP 97) CY SEP 07-11, 1997 CL LAQUILA, ITALY SP Inst Nazl Fisica Nucleare (INFN) ID DETECTORS AB We are conducting an experiment to search for WIMPs. or weakly-interacting massive particles, in the galactic halo using terrestrial detectors. This generic class of hypothetical particles, whose properties are similar to those predicted by extensions of the standard model of particle physics, could comprise the cold component of non-baryonic dark matter. We describe our experiment. which is based on cooled germanium and silicon detectors in a shielded low-background cryostat. The detectors achieve a high degree of background rejection through the simultaneous measurement of the energy in phonons and ionization, Using exposures on the order of one kilogram day from initial runs of our experiment, we have achieved (preliminar) upper limits on the WIMP-nucleon cross section that are comparable to much longer runs of other experiments. C1 Case Western Reserve Univ, Dept Phys, Cleveland, OH 44106 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Russian Acad Sci, Baksan Neutrino Observ, Inst Nucl Res, Moscow 117901, Russia. Santa Clara Univ, Dept Phys, Santa Clara, CA 95053 USA. RP Akerib, DS (reprint author), Case Western Reserve Univ, Dept Phys, Cleveland, OH 44106 USA. NR 14 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 70 BP 64 EP 68 DI 10.1016/S0920-5632(98)00389-2 PG 5 WC Physics, Particles & Fields SC Physics GA 122EQ UT WOS:000076059300008 ER PT J AU Aalseth, CE Avignone, FT Brodzinski, RL Collar, JI Gonzales, D Garcia, E Hasenbalg, F Hensley, WK Kirpichnikov, IV Klimenko, AA Miley, HS Morales, A Morales, J Ortiz de Solorzano, AO Osetrov, SB Pogosov, VS Puimedon, J Reeves, JH Salinas, A Sarsa, ML Smolnikov, AA Starostin, AS Tamanyan, AG Vasenko, AA Vasiliev, SI Villar, JA AF Aalseth, CE Avignone, FT Brodzinski, RL Collar, JI Gonzales, D Garcia, E Hasenbalg, F Hensley, WK Kirpichnikov, IV Klimenko, AA Miley, HS Morales, A Morales, J Ortiz de Solorzano, AO Osetrov, SB Pogosov, VS Puimedon, J Reeves, JH Salinas, A Sarsa, ML Smolnikov, AA Starostin, AS Tamanyan, AG Vasenko, AA Vasiliev, SI Villar, JA TI The Status of the IGEX Ge-76 Double-Beta decay experiment in 1997 SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 5th International Workshop on Topics in Astroparticle and Underground Physics (TAUP 97) CY SEP 07-11, 1997 CL LAQUILA, ITALY SP Inst Nazl Fisica Nucleare (INFN) ID SHELL-MODEL; SUPPRESSION; SE-82 AB The International Germanium Experiment (IGEX) has six detectors containing similar to 90 fiducial moles of Ge-76. Data from 74.84 fiducial mole years yield a lower bound T-1/2(0 nu), > 0.8 x 10(25) y for neutrinoless double-beta decay of Ge-76. C1 Univ S Carolina, Columbia, SC 29208 USA. Pacific NW Lab, Richland, WA 99352 USA. Univ Zaragoza, E-50009 Zaragoza, Spain. Inst Theoret & Expt Phys, Moscow 117259, Russia. Yerevan Phys Inst, Yerevan 375036, Armenia. CERN, Div PPE, Geneva 23, Switzerland. CNEA, Tandar Lab, Dept Phys, Buenos Aires, DF, Argentina. RP Aalseth, CE (reprint author), Univ S Carolina, Columbia, SC 29208 USA. RI Sarsa Sarsa, Maria Luisa/K-6108-2014; Villar, Jose Angel/K-6630-2014; OI Sarsa Sarsa, Maria Luisa/0000-0002-7552-1228; Villar, Jose Angel/0000-0003-0228-7589; Garcia Abancens, Eduardo/0000-0002-9827-2332 NR 14 TC 10 Z9 10 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 70 BP 236 EP 238 DI 10.1016/S0920-5632(98)00426-5 PG 3 WC Physics, Particles & Fields SC Physics GA 122EQ UT WOS:000076059300045 ER PT J AU Kafka, T AF Kafka, T CA Soudan 2 Collaboration TI Atmospheric neutrino interactions in Soudan-2 SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 5th International Workshop on Topics in Astroparticle and Underground Physics (TAUP 97) CY SEP 07-11, 1997 CL LAQUILA, ITALY SP Inst Nazl Fisica Nucleare (INFN) ID TRACKING CALORIMETER MODULES; DETECTOR AB A new measurement of the atmospheric nu(mu)/nu(e) ratio-of-ratios, 0.61 +/- 0.15 +/- 0.05, has been obtained using a 3.2-kty exposure of the Soudan-2 underground detector. This measurement, based upon neutrino reactions in an iron tracking calorimeter of honeycomb-lattice geometry, is in agreement with the anomalously low value reported by the underground water detectors. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Minnesota, Minneapolis, MN 55455 USA. Tufts Univ, Medford, MA 02155 USA. Univ Oxford, Oxford OX1 2JD, England. Rutherford Appleton Lab, Chilton, England. Tufts Univ, Medford, MA 02155 USA. RP Kafka, T (reprint author), Tufts Univ, 4 Colby St, Medford, MA 02155 USA. NR 5 TC 12 Z9 12 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 70 BP 340 EP 344 DI 10.1016/S0920-5632(98)00446-0 PG 5 WC Physics, Particles & Fields SC Physics GA 122EQ UT WOS:000076059300065 ER PT J AU Andres, E Askebjer, P Barwick, SW Bay, R Bergstrom, L Bouchta, A Biron, A Carius, S Costa, C Cowen, D Dalberg, E Ekstrom, P Goobar, A Gray, L Hallgren, A Halzen, F Hart, S He, Y Hill, G Hulth, PO Hundertmark, S Jacobsen, J Jones, A Kandahai, V Karle, A Lindahl, P Liubarsky, I Lowder, DM Marciniewski, P Mikolajski, T Miller, T Mock, P Morse, R Niessen, P Nygren, D de los Heros, CP Porrata, R Potter, D Price, PB Richards, A Rubinstein, H Schneider, E Schwarz, R Spiering, C Streicher, O Thon, T Tilav, S Walck, C Wiebusch, C Wischnewski, R Woschnagg, K Yodh, G AF Andres, E Askebjer, P Barwick, SW Bay, R Bergstrom, L Bouchta, A Biron, A Carius, S Costa, C Cowen, D Dalberg, E Ekstrom, P Goobar, A Gray, L Hallgren, A Halzen, F Hart, S He, Y Hill, G Hulth, PO Hundertmark, S Jacobsen, J Jones, A Kandahai, V Karle, A Lindahl, P Liubarsky, I Lowder, DM Marciniewski, P Mikolajski, T Miller, T Mock, P Morse, R Niessen, P Nygren, D de los Heros, CP Porrata, R Potter, D Price, PB Richards, A Rubinstein, H Schneider, E Schwarz, R Spiering, C Streicher, O Thon, T Tilav, S Walck, C Wiebusch, C Wischnewski, R Woschnagg, K Yodh, G CA AMANDA Collaboration TI Status of the AMANDA experiment SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 5th International Workshop on Topics in Astroparticle and Underground Physics (TAUP 97) CY SEP 07-11, 1997 CL LAQUILA, ITALY SP Inst Nazl Fisica Nucleare (INFN) ID SOUTH-POLE; TRANSMISSION; ICE AB The AMANDA high energy neutrino telescope has successfully been increased in size from four detector strings to ten detector strings during the 1996/1997 season. The first upward going muon-neutrino candidates have been reconstructed from the 1996 year's four-string data. Three new detector strings will be deployed during 1997/1998 to 2350 metres depth. C1 Stockholm Univ, SE-11385 Stockholm, Sweden. Univ Calif Irvine, Dept Phys, Irvine, CA 92717 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. DESY, D-15735 Zeuthen, Germany. Kalmar Univ, Dept Technol, SE-39129 Kalmar, Sweden. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. Univ Uppsala, Dept Radiat Sci, SE-75121 Uppsala, Sweden. Univ Delaware, Bartol Res Inst, Newark, DE 19716 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys, Berkeley, CA 94720 USA. RP Andres, E (reprint author), Stockholm Univ, Box 6703, SE-11385 Stockholm, Sweden. RI Wiebusch, Christopher/G-6490-2012; Hundertmark, Stephan/A-6592-2010; Hallgren, Allan/A-8963-2013; OI Wiebusch, Christopher/0000-0002-6418-3008; Streicher, Ole/0000-0001-7751-1843; Perez de los Heros, Carlos/0000-0002-2084-5866 NR 7 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 70 BP 448 EP 452 DI 10.1016/S0920-5632(98)00468-X PG 5 WC Physics, Particles & Fields SC Physics GA 122EQ UT WOS:000076059300087 ER PT J AU Bugg, W Cohn, H Efremenko, Y Fazely, A Gabriel, T Kamyshkov, Y Plasil, F Svoboda, R AF Bugg, W Cohn, H Efremenko, Y Fazely, A Gabriel, T Kamyshkov, Y Plasil, F Svoboda, R TI ORLANDO - Oak Ridge Large Neutrino Detector SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 5th International Workshop on Topics in Astroparticle and Underground Physics (TAUP 97) CY SEP 07-11, 1997 CL LAQUILA, ITALY SP Inst Nazl Fisica Nucleare (INFN) ID OSCILLATIONS; PHYSICS; SEARCH; KARMEN; BEAM AB We discuss a proposal for construction of an Oak Ridge LArge Neutrino DetectOr (ORLANDO) to search for neutrino oscillations at the Spallation Neutron Source (SNS). A 4 MW SNS is proposed to be built at the Oak Ridge National Laboratory with the first stage to be operative around 2006. It will have two target stations, which makes it possible with a single detector to perform a neutrino oscillation search at two different distances. Initial plans for the placement of the detector and the discovery potential of such a detector are discussed. C1 Univ Tennessee, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Southern Univ, Baton Rouge, LA 70813 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. RP Bugg, W (reprint author), Univ Tennessee, Knoxville, TN 37996 USA. RI Kamyshkov, Yuri/J-7999-2016 OI Kamyshkov, Yuri/0000-0002-3789-7152 NR 14 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 70 BP 472 EP 474 DI 10.1016/S0920-5632(98)00474-5 PG 3 WC Physics, Particles & Fields SC Physics GA 122EQ UT WOS:000076059300093 ER PT J AU Fenimore, EE AF Fenimore, EE TI Gamma-ray burst spectra and time histories from 2 to 400 keV SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT Symposium on the Active X-ray Sky CY OCT 21-24, 1996 CL ROME, ITALY ID GINGA AB The Gamma-Ray burst detector on Ginga consisted of a proportional counter to observe the x-rays and a scintillation counter to observe the gamma-rays. It was ideally suited to study the x-rays associated with gamma-ray bursts (GRBs). Ginga detected similar to 120 GRBs and 22 of them had sufficient statistics to determine spectra from 2 to 400 keV. Although the Ginga and BATSE trigger criteria were very similar, the distribution of spectral parameters was different. Ginga observed bend energies in the spectra down to 2 keV and had a larger fraction of bursts with low energy power law indexes greater than zero. The average ratio of energy in the x-ray band (2 to 10 keV) compared to the gamma-ray band (50 to 300 keV) was 24%. Some events had more energy in the x-ray band than in the gamma-ray band. One Ginga event had a period of time preceding the gamma rays that was effectively pure x-ray emission. This x-ray "preactivity" might be due to the penchant for the GRB time structure to be broader at lower energy rather than a different physical process. The x-rays tend to rise and fall slower than the gamma rays but they both tend to peak at about the same time. This argues against models involving the injection of relativistic electrons that cool by synchrotron radiation. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Fenimore, EE (reprint author), Univ Calif Los Alamos Natl Lab, MS D436, Los Alamos, NM 87544 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 69 IS 1-3 BP 635 EP 639 DI 10.1016/S0920-5632(98)00313-2 PG 5 WC Physics, Particles & Fields SC Physics GA 121WM UT WOS:000076038800124 ER PT J AU Prokofiev, AV Mashnik, SG Sierk, AJ AF Prokofiev, AV Mashnik, SG Sierk, AJ TI Cascade-exciton model analysis of nucleon-induced fission cross sections of lead and bismuth at 45- to 500-MeV energies SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID INTERMEDIATE AB An extended version of the cascade-exciton model (CEM) of nuclear reactions is applied to analyze nucleon-induced fission cross sections for Bi-209 and Pb-208 nuclei in the 45- to 500-MeV energy range. The available data on linear momentum transfer are analyzed as well. The results are compared with analytical approximations resulting from a comparative critical analysis of all available experimental data. Systematic discrepancies between calculations and experimental data are revealed. A modification of the CEM is proposed, which significantly improves the model predictions for projectile energies above 100 MeV. C1 VG Khlopin Radium Inst, St Petersburg 194021, Russia. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Prokofiev, AV (reprint author), VG Khlopin Radium Inst, 2nd Murinsky Av 28, St Petersburg 194021, Russia. OI Prokofiev, Alexander/0000-0002-4225-8910 NR 84 TC 18 Z9 20 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD JAN PY 1999 VL 131 IS 1 BP 78 EP 95 PG 18 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 151ZC UT WOS:000077749800005 ER PT J AU Titarenko, YE Shvedov, OV Igumnov, MM Karpikhin, EI Batyaev, VF Volk, VI Vakhrushin, AY Shepelkov, SV Lopatkin, AV Mashnik, SG Gabriel, TA AF Titarenko, YE Shvedov, OV Igumnov, MM Karpikhin, EI Batyaev, VF Volk, VI Vakhrushin, AY Shepelkov, SV Lopatkin, AV Mashnik, SG Gabriel, TA TI Experimental determination of the resonance integral for Np-237 in a heavy water solution SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article AB Experimental determination of the resonance neutron absorption in a heavy water solution of 2.57 g/l Np-237 is presented. Experimental samples were irradiated in the MAKET critical plant. Prior to irradiation, Np-237 was radiochemically purified to remove Pa-233. The experimental samples were prepared by evaporating two aliquot samples taken from the irradiated solution. The nuclide composition of the samples was analyzed using a GC-2518 Ge detector a 1510 module, and an S-100 plate to emulate a multichannel analyzer in an IBM personal computer: The spectrometric resolution was 1.8 keV at the 1332-keV line. The gamma spectra were processed by the ASPRO code. The neutron flux was measured by two methods using Al + Mn-55 + Cu-nat + Au-197 + Lu-nat alloy foils. C1 Inst Theoret & Expt Phys, State Sci Ctr Russian Federat, Moscow 117259, Russia. All Union Inorgan Mat Res Inst, State Sci Ctr Russian Federat, Moscow 123060, Russia. Res & Dev Inst Power Engn, Dubna 101000, Russia. Joint Inst Nucl Res, Bogoliubov Lab Theoret Phys, Dubna 141980, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Titarenko, YE (reprint author), Inst Theoret & Expt Phys, State Sci Ctr Russian Federat, Moscow 117259, Russia. NR 9 TC 1 Z9 1 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD JAN PY 1999 VL 131 IS 1 BP 96 EP 106 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 151ZC UT WOS:000077749800006 ER PT S AU Dean, DJ White, JA AF Dean, DJ White, JA BE Baktash, C TI Monte Carlo methods and applications for the nuclear shell model SO NUCLEAR STRUCTURE 98 SE AIP Conference Proceedings LA English DT Proceedings Paper CT Conference on Nuclear Structure 98 CY AUG 10-15, 1998 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Phys Div, Lockheed Martin Energy Res Corp, Joint Inst Heavy Ion Res, EG&G ORTEC, EURISYS MESURES Inc, LeCroy, SCIONIX, WIENER US ID NEUTRON-RICH NUCLEI; N = 20; ISOTOPES; REGION; DEFORMATION; RB-74 AB The shell-model Monte Carlo (SMMC) technique transforms the traditional nuclear shell-model problem into a path-integral over auxiliary fields. We describe below the method and its applications to four physics issues: calculations of sd-pf- shell nuclei, a discussion of electron-capture rates in pf-shell nuclei, exploration of pairing correlations in unstable nuclei, and lever densities in rare earth systems. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. EM deandj@ornl.gov; jody@krl.caltech.edu NR 42 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 1-56396-858-4 J9 AIP CONF PROC PY 1999 VL 481 BP 28 EP 40 PG 13 WC Physics, Nuclear SC Physics GA BN89B UT WOS:000083360400003 ER PT S AU Reiter, P Khoo, TL Lister, CJ Seweryniak, D Ahmad, I Alcorta, M Carpenter, MP Cizewski, JA Davids, CN Gervais, G Greene, JP Henning, WF Janssens, RVF Lauritsen, T Siem, S Sonzogni, AA Sullivan, D Uusitalo, J Wiedenhover, I Amzal, N Butler, PA Chewter, AJ Ding, KY Fotiades, N Fox, JD Greenlees, PT Herzberg, RD Jones, GD Korten, W Leino, M Vetter, K AF Reiter, P Khoo, TL Lister, CJ Seweryniak, D Ahmad, I Alcorta, M Carpenter, MP Cizewski, JA Davids, CN Gervais, G Greene, JP Henning, WF Janssens, RVF Lauritsen, T Siem, S Sonzogni, AA Sullivan, D Uusitalo, J Wiedenhover, I Amzal, N Butler, PA Chewter, AJ Ding, KY Fotiades, N Fox, JD Greenlees, PT Herzberg, RD Jones, GD Korten, W Leino, M Vetter, K BE Baktash, C TI Structure and formation mechanism of the transfermium isotope No-254 SO NUCLEAR STRUCTURE 98 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on Nuclear Structure 98 CY AUG 10-15, 1998 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Phys Div, Lockheed Martin Energy Res Corp, Joint Inst Heavy Ion Res, EG&G ORTEC, EURISYS MESURES Inc, LeCroy, SCIONIX, WIENER US ID SUPERHEAVY NUCLEI; SHELL STRUCTURE; ELEMENTS; SPINS; BANDS AB The ground-state band of the Z=102 isotope No-254 has, been identified up to spin 14, indicating that the nucleus is deformed. The deduced quadrupole deformation, beta = 0.27, is in agreement with theoretical predictions. These observations confirm that the shell-correction energy responsible for the stability of transfermium nuclei is partly derived from deformation. The survival of No up to spin 14 means that its fission barrier persists at least up to that spin. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Reiter, P (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Alcorta, Martin/G-7107-2011; Herzberg, Rolf-Dietmar/E-1558-2011; Carpenter, Michael/E-4287-2015; KORTEN, Wolfram/H-3043-2013 OI Alcorta, Martin/0000-0002-6217-5004; Carpenter, Michael/0000-0002-3237-5734; NR 18 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 1-56396-858-4 J9 AIP CONF PROC PY 1999 VL 481 BP 121 EP 126 PG 6 WC Physics, Nuclear SC Physics GA BN89B UT WOS:000083360400011 ER PT S AU Paul, SD Baktash, C Satula, W Gross, CJ Birriel, I Clark, RM Cunningham, RA Devlin, M Fallon, P Galindo-Uribarri, A Ginter, T Lafosse, DR Kay, J Lerma, F Lee, IY Leyland, C Macchiavelli, AO MacDonald, BD Metcalfe, SJ Piechaczek, A Radford, DC Reviol, W Riedinger, LL Rudolph, D Rykaczewski, K Sarantites, DG Saladin, JX Shapira, D Sylvan, GN Tabor, SL Toth, KS Weintraub, W Winchell, DF Wood, VQ Wyss, R Yu, CH AF Paul, SD Baktash, C Satula, W Gross, CJ Birriel, I Clark, RM Cunningham, RA Devlin, M Fallon, P Galindo-Uribarri, A Ginter, T Lafosse, DR Kay, J Lerma, F Lee, IY Leyland, C Macchiavelli, AO MacDonald, BD Metcalfe, SJ Piechaczek, A Radford, DC Reviol, W Riedinger, LL Rudolph, D Rykaczewski, K Sarantites, DG Saladin, JX Shapira, D Sylvan, GN Tabor, SL Toth, KS Weintraub, W Winchell, DF Wood, VQ Wyss, R Yu, CH BE Baktash, C TI Band structure in Y-79 and the question of T=0 pairing SO NUCLEAR STRUCTURE 98 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on Nuclear Structure 98 CY AUG 10-15, 1998 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Phys Div, Lockheed Martin Energy Res Corp, Joint Inst Heavy Ion Res, EG&G ORTEC, EURISYS MESURES Inc, LeCroy, SCIONIX, WIENER US ID SHAPE TRANSITION; EXCITED-STATES; NUCLEI; IDENTIFICATION; ISOTOPES; REGION; RB-74 AB Excited states in the N = Z+1 nucleus Y-79 Were identified using the reaction Si-28(Fe-54, p2n)Y-79 at a 200 MeV beam energy and an experimental set up consisting of an array of Ge detectors and the Recoil Mass Spectrometer at Oak Ridge National Laboratory. With the help of additional gamma-gamma coincidence data obtained with Gammasphere, these gamma-rays were found to form a strongly-coupled rotational band with rigid-rotor-like behavior. Results of conventional Nilsson-Strutinsky cranked shell model calculations, which predict a deformation of beta(2)similar to 0.4, are in excellent agreement with the properties of this band. Similar calculations for the neighboring N = Z and N = Z + 1 nuclei are also in good agreement with experimental data. This suggests that the presence of the putative T = 0 neutron-proton pairing does not significantly affect such simple observables as the moments of inertia of these bands at low spins. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Paul, SD (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RI radford, David/A-3928-2015; Devlin, Matthew/B-5089-2013 OI Devlin, Matthew/0000-0002-6948-2154 NR 28 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 1-56396-858-4 J9 AIP CONF PROC PY 1999 VL 481 BP 168 EP 176 PG 9 WC Physics, Nuclear SC Physics GA BN89B UT WOS:000083360400016 ER PT S AU Batchelder, JC Bingham, CR Gross, CJ Grzywacz, R Rykaczewski, K Toth, KS Zganjar, EF Akovali, Y Davinson, T Ginter, TN Hamilton, JH Janas, Z Karny, M Kim, SH MacDonald, BD Mas, JF McConnell, JW Piechaczek, A Ressler, JJ Slinger, RC Szerypo, J Weintraub, W Woods, PJ Yu, CH AF Batchelder, JC Bingham, CR Gross, CJ Grzywacz, R Rykaczewski, K Toth, KS Zganjar, EF Akovali, Y Davinson, T Ginter, TN Hamilton, JH Janas, Z Karny, M Kim, SH MacDonald, BD Mas, JF McConnell, JW Piechaczek, A Ressler, JJ Slinger, RC Szerypo, J Weintraub, W Woods, PJ Yu, CH BE Baktash, C TI Proton decay studies of the light Lu, Tm and Ho isotopes SO NUCLEAR STRUCTURE 98 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on Nuclear Structure 98 CY AUG 10-15, 1998 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Phys Div, Lockheed Martin Energy Res Corp, Joint Inst Heavy Ion Res, EG&G ORTEC, EURISYS MESURES Inc, LeCroy, SCIONIX, WIENER US ID DEFORMED-NUCLEI; RADIOACTIVITY; EMITTERS; DEFORMATIONS; ENERGIES; TM-147 AB A double-sided Si-strip detector system has been installed and commissioned at the focal plane of the Recoil Mass Spectrometer at the Holifield Radioactive Ion Beam Facility. The system can be used for heavy charged particle emission studies with half-lives as low as a few mu sec. In this paper we present identification and study of the decay properties of the five new proton emitters: Ho-140, Ho-141m, Tm-145, Lu-150m and Lu-151m. C1 Oak Ridge Associated Univ, Oak Ridge, TN 37831 USA. RP Batchelder, JC (reprint author), Oak Ridge Associated Univ, Oak Ridge, TN 37831 USA. RI Ressler, Jennifer Jo/F-2279-2010 NR 27 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 1-56396-858-4 J9 AIP CONF PROC PY 1999 VL 481 BP 216 EP 225 PG 10 WC Physics, Nuclear SC Physics GA BN89B UT WOS:000083360400021 ER PT S AU Lane, GJ Dracoulis, GD Byrne, AP McGoram, TR Poletti, AR AF Lane, GJ Dracoulis, GD Byrne, AP McGoram, TR Poletti, AR BE Baktash, C TI Incomplete-fusion reactions for gamma-ray spectroscopy: application to the study of high-spin states in U-234 SO NUCLEAR STRUCTURE 98 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on Nuclear Structure 98 CY AUG 10-15, 1998 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Phys Div, Lockheed Martin Energy Res Corp, Joint Inst Heavy Ion Res, EG&G ORTEC, EURISYS MESURES Inc, LeCroy, SCIONIX, WIENER US ID PO-211; ISOMER AB Incomplete-fusion reactions occur when breakup of the projectile results in only part of the beam particle fusing with the target, the remnant being emitted with an energy equivalent to the beam velocity. Such reactions have been demonstrated to populate slightly neutron-rich nuclei compared to conventional fusion-evaporation reactions, opening possibilities for the study of nuclei along the neutron-rich side of the line of stability. Results from a study of Po-211 are presented to illustrate the use of incomplete-fusion reactions for gamma-ray spectroscopy. New results from a test-run which populated high-spin states in U-234 via the Th-232(Be-9,alpha 3n) reaction are also presented. An interesting feature of the latter reaction is that the high fission probabilities for the compound nuclei which follow complete fusion, results in the residues from incomplete fusion forming the dominant residue channels. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Lane, GJ (reprint author), Lawrence Berkeley Lab, 1 Cyclotron Rd,MS-88, Berkeley, CA 94720 USA. NR 21 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 1-56396-858-4 J9 AIP CONF PROC PY 1999 VL 481 BP 304 EP 311 PG 8 WC Physics, Nuclear SC Physics GA BN89B UT WOS:000083360400031 ER PT S AU Carpenter, MP Janssens, RVF AF Carpenter, MP Janssens, RVF BE Baktash, C TI Superdeformation in the A=150 and A=190 regions SO NUCLEAR STRUCTURE 98 SE AIP Conference Proceedings LA English DT Proceedings Paper CT Conference on Nuclear Structure 98 CY AUG 10-15, 1998 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Phys Div, Lockheed Martin Energy Res Corp, Joint Inst Heavy Ion Res, EG&G ORTEC, EURISYS MESURES Inc, LeCroy, SCIONIX, WIENER US ID DIFFERENTIAL LIFETIME MEASUREMENTS; IDENTICAL BANDS; DELTA-I=4 BIFURCATION; PSEUDOSPIN SYMMETRY; QUADRUPOLE-MOMENTS; OCTUPOLE CORRELATIONS; LINKING TRANSITIONS; EXTREME CONDITIONS; ROTATIONAL BANDS; QUASI-PARTICLE AB Superdeformation has been established for over a decade in the mass 150 region and nearly as long in the A = 190 region. The first measurements directed at nuclei in these regions concentrated on mapping out the superdeformed (SD) islands by identifying SD rotational bands in gamma-ray coincidence data. These early studies provided new insights into the physics of superdeformation, but also raised unexpected issues. The new gamma-ray arrays (Gammasphere, Eurogam/Euroball and Gasp) have provided a wealth of new data on properties of SD states in these two mass regions. This paper highlights some of the more recent results from the large arrays which have addressed the outstanding issues in the field, namely, Delta I = 4 staggering, identical bands, SD vibrational bands, and questions about the feeding into and the decay out of the SD well. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Carpenter, Michael/E-4287-2015 OI Carpenter, Michael/0000-0002-3237-5734 NR 78 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 1-56396-858-4 J9 AIP CONF PROC PY 1999 VL 481 BP 393 EP 406 PG 14 WC Physics, Nuclear SC Physics GA BN89B UT WOS:000083360400040 ER PT S AU Younes, W Archer, DE Becker, JA Bernstein, LA Garrett, PE Warr, N Kadi, M Martin, A Yates, SW Johns, GD Nelson, RO Wilburn, WS AF Younes, W Archer, DE Becker, JA Bernstein, LA Garrett, PE Warr, N Kadi, M Martin, A Yates, SW Johns, GD Nelson, RO Wilburn, WS BE Baktash, C TI Two-phonon excitations in Er-170 SO NUCLEAR STRUCTURE 98 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on Nuclear Structure 98 CY AUG 10-15, 1998 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Phys Div, Lockheed Martin Energy Res Corp, Joint Inst Heavy Ion Res, EG&G ORTEC, EURISYS MESURES Inc, LeCroy, SCIONIX, WIENER US ID GAMMA-VIBRATIONAL STATES; EVEN-EVEN NUCLEI; DEFORMED-NUCLEI; 2-QUASI-PARTICLE STATES; TRANSITIONS; QUADRUPOLE; DY-164 AB Recent experiments at the GEANIE/WNR facility and the University of Kentucky accelerator have yielded strong evidence for a two-gamma excitation in Er-170. This new case can be added to a handful of previously identified examples of two-gamma vibrations, all of them discovered in this decade. in this paper the experimental evidence for a two-phonon excitation Er-170 is presented and the current state of understanding of these structures is reviewed in the context of this and other recent findings. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Younes, W (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Kadi, Mohammad/H-6114-2012 OI Kadi, Mohammad/0000-0002-5010-9536 NR 37 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 1-56396-858-4 J9 AIP CONF PROC PY 1999 VL 481 BP 464 EP 472 PG 9 WC Physics, Nuclear SC Physics GA BN89B UT WOS:000083360400047 ER PT S AU Macchiavelli, AO Clark, RM Deleplanque, MA Diamond, RT Fallon, P Lee, IY Stephens, FS Vetter, K AF Macchiavelli, AO Clark, RM Deleplanque, MA Diamond, RT Fallon, P Lee, IY Stephens, FS Vetter, K BE Baktash, C TI Semi-classical shears and effective forces SO NUCLEAR STRUCTURE 98 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on Nuclear Structure 98 CY AUG 10-15, 1998 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Phys Div, Lockheed Martin Energy Res Corp, Joint Inst Heavy Ion Res, EG&G ORTEC, EURISYS MESURES Inc, LeCroy, SCIONIX, WIENER US ID ROTATIONAL BAND; MECHANISM AB We present a semi-classical analysis of the B(M1) and B(E2) transition probabilities in the shears bands in (193-199) Pb as a function of the shears angle. This provides a semi-empirical confirmation of the shears mechanism proposed by S. Frauendorf using the Tilted-Axis-Cranking model. We interpret this as a consequence of a residual interaction between the proton and neutron blades, and it is shown that the main ingredient of this effective force can be described by a P-2(theta) term with a strength of 400 - 600 keV. Such an interaction can be mediated through the core by particle-vibration coupling. The competition between the shears and the rotation of the core is investigated within the framework of a classical solution of two particles-plus-rotor model. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Macchiavelli, AO (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. NR 19 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 1-56396-858-4 J9 AIP CONF PROC PY 1999 VL 481 BP 517 EP 526 PG 10 WC Physics, Nuclear SC Physics GA BN89B UT WOS:000083360400052 ER PT S AU Wiedenhover, I Janssens, RVF Hackman, G Ahmad, I Greene, JP Amro, H Carpenter, MP Nisius, DT Reiter, P Lauritsen, T Lister, CJ Khoo, TL Siem, S Cizewski, J Seweryniak, D Uusitalo, J Macchiavelli, AO Chowdhury, P Seabury, EH Cline, D Wu, CY AF Wiedenhover, I Janssens, RVF Hackman, G Ahmad, I Greene, JP Amro, H Carpenter, MP Nisius, DT Reiter, P Lauritsen, T Lister, CJ Khoo, TL Siem, S Cizewski, J Seweryniak, D Uusitalo, J Macchiavelli, AO Chowdhury, P Seabury, EH Cline, D Wu, CY BE Baktash, C TI Unsafe Coulomb excitation of Pu240-244 SO NUCLEAR STRUCTURE 98 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on Nuclear Structure 98 CY AUG 10-15, 1998 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Phys Div, Lockheed Martin Energy Res Corp, Joint Inst Heavy Ion Res, EG&G ORTEC, EURISYS MESURES Inc, LeCroy, SCIONIX, WIENER US ID NUCLEI AB The high spin states of Pu-240 and Pu-244 have been investigated with GAMMASPHERE at ATLAS, using Coulomb excitation with a Pb-208 beam at energies above the Coulomb barrier. Data on a transfer channel leading to Pu-242 were obtained as well. In the case of Pu-244, the yrast band was extended to 34 (h) over bar, revealing the completed pi i(13/2) alignment, a "first" for actinide nuclei. The yrast sequence of Pu-242 was also extended to higher spin and a similar backbend was delineated. In contrast, white the ground state band of Pu-240 was measured up to the highest rotational frequencies ever reported in the actinide region (similar to 300 keV), no sign of particle alignment was observed. In this case, several observables such as the large B(E1)/B(E2) branching ratios in the negative parity band, and the vanishing energy staggering between the negative and positive parity bands suggest that the strength of octupole correlations increases with rotational frequency. These stronger correlations may well be responsible for delaying or suppressing the pi i(13/2) particle alignment. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Wiedenhover, I (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Carpenter, Michael/E-4287-2015 OI Carpenter, Michael/0000-0002-3237-5734 NR 12 TC 1 Z9 1 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-858-4 J9 AIP CONF PROC PY 1999 VL 481 BP 527 EP 533 PG 7 WC Physics, Nuclear SC Physics GA BN89B UT WOS:000083360400053 ER PT S AU Lee, IY AF Lee, IY BE Baktash, C TI GRETA: Status and physics potentials SO NUCLEAR STRUCTURE 98 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on Nuclear Structure 98 CY AUG 10-15, 1998 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Phys Div, Lockheed Martin Energy Res Corp, Joint Inst Heavy Ion Res, EG&G ORTEC, EURISYS MESURES Inc, LeCroy, SCIONIX, WIENER US AB A gamma-ray tracking detector is a new concept for a detector array composed of highly segmented Ge detector elements. The detector would give the energy and the position of all the interaction points and by using the angle-energy relation of the Compton scattering, the scattering sequence of the gamma rays can be reconstructed. Such a detector will have a high efficiency and a good peak-to-background ratio. Research and development are being carried out in the production of highly segmented Ge detectors, understanding the signal, and development of tracking algorithms. Recent progress indicated that this type of detector system appears to be feasible and would have a large impact on a wide variety of physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Lee, IY (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-858-4 J9 AIP CONF PROC PY 1999 VL 481 BP 563 EP 569 PG 7 WC Physics, Nuclear SC Physics GA BN89B UT WOS:000083360400057 ER PT S AU Radford, DC Cromaz, M Beyer, CJ AF Radford, DC Cromaz, M Beyer, CJ BE Baktash, C TI Analysis of high-fold gamma data SO NUCLEAR STRUCTURE 98 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on Nuclear Structure 98 CY AUG 10-15, 1998 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Phys Div, Lockheed Martin Energy Res Corp, Joint Inst Heavy Ion Res, EG&G ORTEC, EURISYS MESURES Inc, LeCroy, SCIONIX, WIENER US ID COINCIDENCE DATA SETS AB Historically, gamma-gamma and gamma-gamma-gamma coincidence spectra were utilized to build nuclear level schemes. With the development of large detector arrays, it has became possible to analyze higher fold coincidence data sets. This paper briefly reports on software to analyze I-ford coincidence data sets that allows creation of 4-fold histograms (hypercubes) of at least 1024 channels per side (corresponding to a 43 gigachannel data space) that will fit onto a few gigabytes of disk space, and extraction of triple-gated spectra in a few seconds. Future detector arrays may have even much higher efficiencies, and detect as many as 15 or 20 gamma rays simultaneously; such data will require very different algorithms for storage and analysis. Difficulties inherent in the analysis of such data are discussed, and two possible new solutions are presented, namely adaptive list-mode systems and "list-list-mode" storage. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Radford, DC (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RI radford, David/A-3928-2015 NR 6 TC 6 Z9 6 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 1-56396-858-4 J9 AIP CONF PROC PY 1999 VL 481 BP 570 EP 580 PG 11 WC Physics, Nuclear SC Physics GA BN89B UT WOS:000083360400058 ER PT J AU Gougar, MLD Scheetz, BE Siemer, DD AF Gougar, MLD Scheetz, BE Siemer, DD TI A novel waste form for disposal of spent-nuclear-fuel reprocessing waste: A vitrifiable cement SO NUCLEAR TECHNOLOGY LA English DT Article DE radioactive waste; form; hydroceramic; hot isostatically pressed-style vitrification AB A cement capable of being hot isostatically pressed into a glass ceramic has been proposed as the waste form for spent-nuclear-fuel reprocessing wastes at the Idaho National Engineering and Environmental Laboratory (INEEL). This intermediate cement, with a composition based on that of common glasses, has been designed and tested. The cement formulations included mixed INEEL wastes, blast furnace slag, reactive silica, and INEEL soil or vermiculite, which were activated with potassium or sodium hydroxide. Following autoclave processing, the cements were characterized. X-ray diffraction analysis revealed three notable crystalline phases, quartz, calcite, and fluorite. Results of compressive strength testing ranged from 1452 to 4163 psi, exceeding the U.S. Nuclear Regulatory Commission (NRC)-suggested standard of >500 psi. From American National Standards Institute/American Nuclear Society 16.1-1986 leach testing, effective diffusivities for Cs were determined to be on the order of 10(-11) to 10(-10) cm(2)/s and for Sr were 10(-12) cm(2)/s, which are four orders of magnitude less than diffusivities in some other radwaste materials. Average leach indices (LI) were 9.6 and 11.9 for Cs and Sr respectively, meeting the NRC standard of LI > 6. The 28-day Materials Characterization Center-1 leach testing resulted in normalized elemental mass losses between 0.63 and 28 g/(m(2).day) for Cs and between 0.34 and 0.70 g/(m(2).day) for Sr. Strontium mass losses meet the <1 g/(m(2).day) industry-accepted standard while Cs losses indicate a process sensitive parameter. C1 Penn State Univ, Intercoll Mat Res Lab, University Pk, PA 16802 USA. Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Gougar, MLD (reprint author), Penn State Univ, Intercoll Mat Res Lab, University Pk, PA 16802 USA. NR 25 TC 3 Z9 4 U1 1 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD JAN PY 1999 VL 125 IS 1 BP 93 EP 103 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 151NE UT WOS:000077726000008 ER PT J AU Powell, JR Ludewig, H Todosow, M Reich, M AF Powell, JR Ludewig, H Todosow, M Reich, M TI Target and filter concepts for accelerator-driven boron neutron capture therapy applications SO NUCLEAR TECHNOLOGY LA English DT Article DE target/filter; boron capture therapy; neutron source AB Two new accelerator target and neutron filter concepts are proposed for boron neutron capture therapy (BNCT) to enable production efficiencies for epithermal neutrons (i.e., neutrons leaving the treatment port and neutrons generated in the target) of similar to 5 to 10%. These efficiencies are much greater than In previous designs and allow BNCT facilities to use near-term, low-current (similar to 5 mA) proton accelerators. Two target/filter designs are described and their neutronic performance analyzed. Irt NIFTI-1, epithermal neutrons (maximum energy of similar to 100 keV) are generated by a proton beam that is maintained slightly above the 1.889-MeV threshold for the Li-7(p,n)Be-7 reaction. As the proton beam passes through the DISCOS target, which consists of a sequential series (e.g., total of 80) of very thin (several microns) liquid-lithium films on ultrathin rotating beryllium metal foils, the protons are reaccelerated by art applied direct-current field between the foils. This reacceleration enables a high total neutron yield, similar to 10(-4) neutrons/proton. The NIFTI-1 neutron filter a highly scattering cross-section layer of iron-magnesium, located between the target and the treatment port impedes neutron transmission for energies >24 keV, but it has a deep window in the scattering cross section at 24 keV. Scattering in the filter and an accompanying thin (similar to 1 cm) hydrogenous neutron "downshifter" yield a neutron output beam with an average energy of similar to 10 to 20 keV. In the NIFTI-2 design, a single thick lithium target is used, with a proton beam energy (similar to 2.5 MeV) well above the (p,n) thresh old. Although the neutron yield from the target is high, similar to 10(-4) neutrons/proton, their energy is much greater (maximum of similar to 800 keV) than in NIFTI-1. The high-energy neutrons inelastically scatter in a fluorine-containing material (BeF2/PbF2) placed between the target and the NIFTI filter. The neutron beam out of the treatment port has an average energy of similar to 30 keV. The effectiveness of the two designs for BNCT treatment is analyzed. Both exhibit good penetration in tissue (advantage depth) and tumor/healthy tissue dose (relative biological effectiveness advantage ratio) performance. C1 Brookhaven Natl Lab, Dept Adv Technol, Upton, NY 11973 USA. RP Powell, JR (reprint author), Brookhaven Natl Lab, Dept Adv Technol, Bldg 701,POB 5000, Upton, NY 11973 USA. NR 16 TC 5 Z9 5 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD JAN PY 1999 VL 125 IS 1 BP 104 EP 115 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 151NE UT WOS:000077726000009 ER PT S AU Arnone, GL Foster, LA Foxx, CL Hagan, RC Martin, ER Myers, SC Parker, JL AF Arnone, GL Foster, LA Foxx, CL Hagan, RC Martin, ER Myers, SC Parker, JL BE Robertson, DE TI Status of the waste assay for nonradioactive disposal (WAND) project SO NUCLEAR WASTE INSTRUMENTATION ENGINEERING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nuclear Waste Instrumentation Engineering CY NOV 04-05, 1998 CL BOSTON, MA SP SPIE-Int Soc Opt Engn DE minimum detectable activity; Poisson; phoswich; multiplexer; waste screening; radioactive contamination; radiation shielding AB The WAND (Waste Assay for Nonradioactive Disposal) system scans thought-to-be-clean low-density waste (mostly paper and plastics) to verify the absence of radioactive contaminants at very low-levels. Much of the low-density waste generated in radiologically controlled areas, formally considered "suspect" radioactive, is now disposed more cheaply at the Los Alamos County Landfill as opposed to the LANL Radioactive Waste Landfill. The WAND System consists of a well-shielded army of six 5-in. diameter phoswich scintillation detectors; a conveyor belt that carries the low-density waste beneath the detectors; the electronics needed to process the outputs of the detectors; and a desktop computer to control the system and perform data analysis. WAND system minimum detectable activities (MDAs) range from 22 Bq (0.6 nCi) for Am-241 to 296 Bq (8.0 nCi) for Pu-239. MDAs for other important radionuclides (e.g., Pu-240, Pu-238, U-235, U-238) range from 0.4 to 4.4 nCi depending upon the emission probabilities of the photons emitted (gamma-rays and/or x-rays). The system can also detect beta particles of moderate-to-high energy. The only radionuclides not detectable are pure alpha-emitters and very-low-energy beta emitters (e.g., H-3). C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Arnone, GL (reprint author), Univ Calif Los Alamos Natl Lab, MS J562, Los Alamos, NM 87545 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 0-8194-2997-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3536 BP 12 EP 23 DI 10.1117/12.339065 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology SC Instruments & Instrumentation; Nuclear Science & Technology GA BM50T UT WOS:000078921700002 ER PT S AU Stanley, CJ East, LV Twedell, GW Killian, EW Harker, YD AF Stanley, CJ East, LV Twedell, GW Killian, EW Harker, YD BE Robertson, DE TI Instrumentation applications for radioassay of transuranic waste at the Idaho National Engineering and Environmental Laboratory SO NUCLEAR WASTE INSTRUMENTATION ENGINEERING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nuclear Waste Instrumentation Engineering CY NOV 04-05, 1998 CL BOSTON, MA SP SPIE-Int Soc Opt Engn DE neutron assay; transuranic waste; gamma ray spectroscopy; WIPP; radioactive waste; TRU; radioassay; waste assay; nondestructive assay; waste characterization AB The Radioactive Waste Management Complex (RWMC) located within the Idaho National Engineering and Environmental Laboratory (INEEL) contains facilities and equipment to manage and characterize transuranic (TRU) radioactive waste currently stored at the INEEL. This waste was generated primarily at the Department of Energy (DOE) Rocky Flats Plant. A facility referred to as the Stored Waste Examination Pilot Plant (SWEPP) provides space for the systems that characterize and certify the various TRU waste forms for shipping and disposal. This paper describes the processes and instrumentation used to perform nondestructive radioassay on the TRU waste. The equipment includes a passive-active neutron (PAN) assay system used to interrogate the waste container for the presence of fissile materials and a gamma-ray spectrometer (GRS) system used for the identification of the gamma-ray emitting isotopes in the waste containers. The PAN assay system consists of a Zetatron-type pulsed neutron generator; active, passive, and interrogation flux neutron detectors and instrumentation packages, safety interlocks, and various assay chamber signal acquisition instrumentation and processing electronics. The GRS system uses high-resolution, high-purity germanium detectors, amplifiers, high-voltage power supplies, analog-to-digital converters, signal acquisition and interface modules, and the gamma spectra calibration pulsers. The data from these two systems are combined to calculate radionuclide quantities required for the TRU waste characterization, certification, shipping, and disposal at a centralized DOE disposal facility, such as the proposed Waste Isolation Pilot Plant facility in New Mexico. The wide variety of waste matrix types and isotopic distributions has posed a real. challenge to both our radioassay system hardware/software and the technical support personnel assigned to the project. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Radioactive Waste Management Complex, Idaho Falls, ID 83415 USA. RP Stanley, CJ (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Radioactive Waste Management Complex, POB 1625, Idaho Falls, ID 83415 USA. NR 8 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 0-8194-2997-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3536 BP 33 EP 44 DI 10.1117/12.339073 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology SC Instruments & Instrumentation; Nuclear Science & Technology GA BM50T UT WOS:000078921700004 ER PT S AU Blackwood, LG Harker, YD AF Blackwood, LG Harker, YD BE Robertson, DE TI Uncertainty analysis of nondestructive assay measurements of nuclear waste SO NUCLEAR WASTE INSTRUMENTATION ENGINEERING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nuclear Waste Instrumentation Engineering CY NOV 04-05, 1998 CL BOSTON, MA SP SPIE-Int Soc Opt Engn DE uncertainty; non-destructive assay; nuclear waste; statistics AB Regulatory agencies governing the disposal of nuclear waste require that the waste be appropriately characterized prior to disposition. The most important aspect of the characterization process, establishing radionuclide content, is often achieved by nondestructive assay (NDA). For NDA systems to be approved for use in these applications, measurement uncertainty must be established. Standard "propagation of errors" methods provide a good starting point for considering the uncertainty analysis of NDA systems for nuclear waste. However, as compared with other applications (e.g., nuclear material accountability), using NDA systems for nuclear waste measurements presents some unique challenges. These challenges, stemming primarily from the diverse nature of the waste materials encountered, carry over into the uncertainty analysis as well. This paper reviews performance measures appropriate for the assessment of NDA uncertainty, describes characteristics of nuclear waste measurements that contribute to difficulties in assessing uncertainty, and outlines some statistics based methods for incorporating variability in waste characteristics in an uncertainty analysis. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Blackwood, LG (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 5 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 0-8194-2997-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3536 BP 46 EP 57 DI 10.1117/12.339074 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology SC Instruments & Instrumentation; Nuclear Science & Technology GA BM50T UT WOS:000078921700005 ER PT S AU Whitney, PD Chen, G AF Whitney, PD Chen, G BE Robertson, DE TI Statistical analyses of nuclear waste level measurements to estimate retained gas volumes SO NUCLEAR WASTE INSTRUMENTATION ENGINEERING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nuclear Waste Instrumentation Engineering CY NOV 04-05, 1998 CL BOSTON, MA SP SPIE-Int Soc Opt Engn DE nuclear waste; monitoring; statistics AB The Hanford site is home to 177 large, underground nuclear waste storage tanks. Numerous safety and environmental concerns surround these tanks and their contents. One such concern is the propensity for the waste in these tanks to generate and retain flammable gases. The surface level of the waste in these tanks is routinely monitored to assess whether the tanks are leaking. For some of the tanks, the waste surface level measurements synchronously fluctuate with atmospheric pressure changes. The current best explanation for these synchronous fluctuations is that the waste contains gas-phase material that changes volume in response to the atmospheric pressure changes. This paper describes The exploratory data analysis that led to the discovery of the phenomena A physical mode based on the ideal gas law that explains the phenomena. Additionally, the model allows one to obtain estimates of the retained gas volume in the tank waste. A statistical procedure for detecting retained gas based on the physical model and tank surface level measurements A Kalman filter model for analyzing the dynamics of retained gas. It's also shown how the filter can be used to detect abrupt changes in the system. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Whitney, PD (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 12 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 0-8194-2997-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3536 BP 58 EP 68 DI 10.1117/12.339075 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology SC Instruments & Instrumentation; Nuclear Science & Technology GA BM50T UT WOS:000078921700006 ER PT S AU Ferryman, TA Chen, G Amidan, BG Hartley, SA LoPresti, CA Hill, JG DeForest, TJ Gao, F Remund, KM Simpson, BC AF Ferryman, TA Chen, G Amidan, BG Hartley, SA LoPresti, CA Hill, JG DeForest, TJ Gao, F Remund, KM Simpson, BC BE Robertson, DE TI Uncertainty estimation of Hanford tank chemical and radionuclide inventories and concentrations SO NUCLEAR WASTE INSTRUMENTATION ENGINEERING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nuclear Waste Instrumentation Engineering CY NOV 04-05, 1998 CL BOSTON, MA SP SPIE-Int Soc Opt Engn DE waste management; statistics; environmental cleanup; characterization AB The exact physical and chemical nature of 55 million gallons of radioactive toxic waste held in 177 underground waste tanks at the Hanford Site is not known with sufficient detail to support the safety, retrieval, and immobilization missions presented to Hanford. The purpose of this study is to estimate probability distributions for the inventory of each of 72 analytes in each of 177 tanks. This will enable uncertainty intervals to be calculated for inventories and should facilitate the safety, retrieval, and immobilization missions. The methodology presented in this paper is based on scientific principles, sound technical knowledge of the realities associated with the Hanford waste tanks, chemical analysis of samples from the tanks, historical data and other Hanford research. As a result of the processing histories, waste storage practices and historical records, some of the waste can be partitioned into more homogeneous subsets that can be identified to tanks and locations within tanks. Therefore, by using this we can maximize the information extracted from the relatively few samples we have for each tank, combining sample data information from similar tanks to generate a sample based estimate of the chemical and radionuclide concentrations of each of the many waste subsets. Then by multiplying the concentrations for a specific analyte (micrograms of the analyte per gram of waste, or microCuries of the analyte per gram of waste) by the density (grams per liter) by the volume in a tank (liters), we can get an estimate of the mass of a particular analyte (or radionuclide contribution) in each tank. This methodology does this in a probabilistic framework; thus using and generating probability distributions instead of single point estimate numbers. C1 PNNL, Richland, WA 99352 USA. RP Ferryman, TA (reprint author), PNNL, POB 999, Richland, WA 99352 USA. NR 8 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 0-8194-2997-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3536 BP 69 EP 79 DI 10.1117/12.339059 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology SC Instruments & Instrumentation; Nuclear Science & Technology GA BM50T UT WOS:000078921700007 ER PT S AU Daymo, EA Hylton, TD May, TH AF Daymo, EA Hylton, TD May, TH BE Robertson, DE TI Acceptance testing of the Lasentec focused beam reflectance measurement (FBRM) monitor for slurry transfer applications at Hanford and Oak Ridge SO NUCLEAR WASTE INSTRUMENTATION ENGINEERING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nuclear Waste Instrumentation Engineering CY NOV 04-05, 1998 CL BOSTON, MA SP SPIE-Int Soc Opt Engn AB The Lasentec M600F FBRM particle size and population monitor (Lasentec, Redmond, WA) was selected for deployment on radioactive slurry transfer systems at Oak Ridge National Laboratory and Hanford after extensive testing with "physical simulants." These tests indicated that the monitor is able to measure the change in particle size distribution of concentrated (up to 35 vol. %) slurries at flow rates greater than 2 m/sec. As well, the monitor provided relatively stable mean particle size values when air bubbles were introduced to the slurry pipe test loop and when the color of the slurry was altered. Slurry samples taken during each test were analyzed with a laboratory particle size monitor. For kaolin slurry samples (length-cubed weighted mean of around 55 mu m), the Lasentec M600F FBRM in-line monitor measured length-cubed weighted mean particle sizes within 25% of those measured by a laboratory Lasentec M500LF monitor. This difference is thought primarily to be the result of sample handling issues. Regardless, this accuracy is acceptable for radioactive slurry transfer applications. Once deployed, the in-line Lasentec monitor is expected to yield significant cost savings at Hanford and Oak Ridge through the possible reduction in risk of pipeline blockage. In addtion, fewer samples of radioactive slurries will need to be measured in the laboratory, further reducing costs and increasing safety. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Daymo, EA (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 14 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 0-8194-2997-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3536 BP 82 EP 92 DI 10.1117/12.339060 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology SC Instruments & Instrumentation; Nuclear Science & Technology GA BM50T UT WOS:000078921700008 ER PT S AU Hurd, JR AF Hurd, JR BE Robertson, DE TI In-plant measurement and analysis of mixtures of uranium and plutonium TRU-waste using a Cf-252 shuffler instrument SO NUCLEAR WASTE INSTRUMENTATION ENGINEERING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nuclear Waste Instrumentation Engineering CY NOV 04-05, 1998 CL BOSTON, MA SP SPIE-Int Soc Opt Engn DE Cf-252 shuffler; transuranic (TRU)-waste; 55-gallon drums; uranium-plutonium mixtures; matrix calibrations; background radiation; enrichment calculations AB The active-passive Cf-252 shuffler instrument, installed and certified several years ago in Los Alamos National Laboratory's plutonium facility, has now been calibrated for different matrices to measure Waste Isolation Pilot Plant (WIPP)-destined transuranic (TRU)-waste. Little or no data currently exist for these types of measurements in plant environments where sudden large changes in the neutron background radiation can significantly distort the results. Measurements and analyses of twenty-two 55-gallon drums, consisting of mixtures of varying quantities of uranium and plutonium in mostly noncombustible matrices, have been recently completed at the plutonium facility. The calibration and measurement techniques, including the method used to separate out the plutonium component, will be presented and discussed. Calculations used to adjust for differences in uranium enrichment from that of the calibration standards will be shown. Methods used to determine various sources of both random and systematic error will be indicated. Particular attention will be directed to those problems identified as arising from the plant environment. The results of studies to quantify the aforementioned distortion effects in the data will be presented. Various solution scenarios will be outlined, along with those adopted here. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hurd, JR (reprint author), Univ Calif Los Alamos Natl Lab, MS E 513, Los Alamos, NM 87545 USA. NR 11 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 0-8194-2997-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3536 BP 93 EP 103 DI 10.1117/12.339061 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology SC Instruments & Instrumentation; Nuclear Science & Technology GA BM50T UT WOS:000078921700009 ER PT S AU Rodgers, JC Wasiolek, PT Schery, SD Alcantara, RE AF Rodgers, JC Wasiolek, PT Schery, SD Alcantara, RE BE Robertson, DE TI High resolution, real-time optical studies of radiological air sample filtration processes in an environmental continuous air monitor SO NUCLEAR WASTE INSTRUMENTATION ENGINEERING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nuclear Waste Instrumentation Engineering CY NOV 04-05, 1998 CL BOSTON, MA SP SPIE-Int Soc Opt Engn DE continuous air monitor; aerosol particles deposition; dendrite formation; digital microscopy ID ALPHA AB The need for a continuous air monitor capable of quick and accurate measurements of airborne radioactivity in close proximity to the work environment during waste management, site restoration, and D&D operations led to the Los Alamos National Laboratory development of an environmental continuous air monitor (ECAM). Monitoring the hostile work environment of waste recovery, for example, presents unique challenges for detector design for detectors previously used for the clean room conditions of the typical plutonium laboratory. The environmental and atmospheric conditions (dust, high wind, etc.) influence aerosol particle penetration into the ECAM sampling head as well as the build-up of deposits on the ECAM filter. Dust deposits cause complex microstructures to form, onto which incoming plutonium bearing aerosols deposit. This leads to potential degradation in alpha spectroscopy used to detect the relatively few aerosol particles that would be expected to be collected in the early temporal stages of a significant airborne plutonium release incident. From the worker protection perspective, it is the early detection performance that counts, not the ability to ultimately determine the true average concentration during a release episode. Average concentration can be measured more accurately using simple high volume air sampler for collection and retrospective laboratory analysis of the filters. For realistic studies of particulate deposit structure formation on ECAM filters and their impact on alpha spectroscopy, a modified ECAM sampling head equipped with optical microscopy system feeding data to a high resolution video data capture and logging instrument was constructed. The combination of the internally focused microscope with the high-resolution digital camera and image analysis software allows for digital recording and analysis of the filter surface in near real time as aerosol structures evolve during sampling. The mounting of the optical system in the ECAM, in the same geometry as the radiation detector, is critical for realistic aerosol particle penetration and deposition analysis. Collection of alpha spectra using a second ECAM provides data for parallel assessment of the influence of micro-structural features of the filter surface deposits simultaneously with the degradation of the ability of the ECAM system to distinguish isotopes based on their alpha energy. Different types of particulate and atmospheric influences will be brought to bear on determining ECAM operational parameters and selection of filter media that will compensate for the deleterious effects of aerosol microstructure formations during monitoring under adverse conditions. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Rodgers, JC (reprint author), Univ Calif Los Alamos Natl Lab, ESH-4,MS G761, Los Alamos, NM 87545 USA. NR 5 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 0-8194-2997-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3536 BP 138 EP 145 DI 10.1117/12.339066 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology SC Instruments & Instrumentation; Nuclear Science & Technology GA BM50T UT WOS:000078921700013 ER PT S AU Bliss, M Craig, RA Arthur, RJ Winterrose, MD AF Bliss, M Craig, RA Arthur, RJ Winterrose, MD BE Robertson, DE TI Human intrusion monitor for special nuclear material storage facilities SO NUCLEAR WASTE INSTRUMENTATION ENGINEERING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nuclear Waste Instrumentation Engineering CY NOV 04-05, 1998 CL BOSTON, MA SP SPIE-Int Soc Opt Engn AB A radiation detector has been assembled that monitors human intrusion in rooms containing kilogram quantities of special nuclear material (SNM). The detector is fabricated from scintillating glass fibers that contain Li-6 as the neutron absorber. The detector is designed to consume a minimum of power and to be placed in a standing position, thereby presenting a minimum profile and allowing placement in existing facilities. A small footprint is achieved by using intrinsically-thin fiber optics and by undermoderating the system. The detector operates by alarming on a rapid change in the thermal neutron count sate, which corresponds to albedo neutrons that are thermalized or absorbed in the hydrogen and carbon of human body tissues when someone enters the existing neutron flux found in SNM storage rooms. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Bliss, M (reprint author), Pacific NW Natl Lab, Box 999, Richland, WA 99352 USA. RI Bliss, Mary/G-2240-2012 OI Bliss, Mary/0000-0002-7565-4813 NR 1 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 0-8194-2997-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3536 BP 156 EP 158 DI 10.1117/12.339068 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology SC Instruments & Instrumentation; Nuclear Science & Technology GA BM50T UT WOS:000078921700015 ER PT S AU Haggard, DL Tanner, JE Mapili, GM Mozhayev, A Savlov, A AF Haggard, DL Tanner, JE Mapili, GM Mozhayev, A Savlov, A BE Robertson, DE TI Neutron coincidence counting of plutonium or is it high-energy muon-induced time-correlated events in lead SO NUCLEAR WASTE INSTRUMENTATION ENGINEERING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nuclear Waste Instrumentation Engineering CY NOV 04-05, 1998 CL BOSTON, MA SP SPIE-Int Soc Opt Engn AB Coincidence counting of time-correlated spontaneous fission neutrons from even-atomic-numbered Pu isotopes has been a well documented methodology for determining quantitatively the amount of Pu present in a waste container. Recently, a number of 55-gallon radioactive mixed waste drums were assayed on Pacific Northwest National Laboratory's (PNNL) segmented gamma scan neutron assay system (SGSNAS). The drums weighed 680, 750, and 529 pounds, respectively. A large portion of the drum weight consisted of "potentially contaminated Pb bricks." The Pb brick waste was originally used as radiological shielding. The Pb brick shielding was loaded into 55-gallon drums during decontamination and hot cell clean out operations. The drums were then sent to PNNL's nondestructive assay facility for counting. In each case, the results were TRANSURANIC. No gamma ray lines were present to support a TRU result. However, the neutron coincidence "reals" were detected in numbers well above background levels. The third drum, weighing 529 pounds, was not part of a contaminated area clean out and therefore raised some serious questions. How could this possibly be TRU waste? The counting system was operating perfectly having recently passed the fourth cycle of the Waste Isolation Pilot Plant (WIPP) performance demonstration program. The SGSNAS system was rechecked using (AmLi)-Am-241 and Cf-252 standards to test the system's singles and doubles (reals) response functions and gate timing. Having passed these tests, another test was implemented. Twenty clean, Pb bricks (500 pounds) were loaded into a new 55-gallon drum. Each Pb brick was 2 " high by 4 " wide by 8 " long and weighed approximately 25 pounds. The Pb stack consisted of 2 bricks per layer - ten layers (20 ") high. The first 2000-second neutron count gave a Pu gram equivalent "reals" rate of 1.87 g. This paper will show the results of subsequent measurements, the Pu gram equivalents, and coincidences of the presumed muon-initiated events versus the amount of Pb present. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Haggard, DL (reprint author), Pacific NW Natl Lab, POB 999,MSIN P7-27, Richland, WA 99352 USA. NR 1 TC 4 Z9 4 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 0-8194-2997-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3536 BP 159 EP 167 DI 10.1117/12.339069 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology SC Instruments & Instrumentation; Nuclear Science & Technology GA BM50T UT WOS:000078921700016 ER PT S AU Foster, LA AF Foster, LA BE Robertson, DE TI Non-destructive assay of curium contaminated transuranic waste drums SO NUCLEAR WASTE INSTRUMENTATION ENGINEERING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nuclear Waste Instrumentation Engineering CY NOV 04-05, 1998 CL BOSTON, MA SP SPIE-Int Soc Opt Engn DE plutonium; curium; nondestructive assay; shuffler; neutron; transuranic waste AB At the Plutonium Facility at Los Alamos National Laboratory, a series of non-destructive assays were performed on five transuranic (TRU) waste drums containing non-actinide scrap metal that was potentially contaminated with weapons grade plutonium and trace quantities of curium. Typically, waste drums containing metal matrices are assayed for plutonium content using passive neutron coincidence counting techniques. The presence of trace quantities of Cm-244 prevents this type of analysis because of the strong coincidence signal created by spontaneous fission of 244Cm. To discriminate between the plutonium and curium materials in the matrix, an active neutron measurement technique was used. A californium shuffler designed for measurement of uranium bearing materials was calibrated for plutonium in the active mode. The waste drums were then assayed for plutonium content in the shuffler using the active-mode calibration, which is relatively insensitive to the 244Cm contamination. The curium contamination levels were estimated from the difference between the active-mode measurement in the shuffler and a passive assay in a neutron coincidence counter. Far field gamma-ray measurements were made to identify additional radioactive contaminants and to corroborate the plutonium measurement results obtained from the active-mode assay. This report describes in detail the measurement process used for characterization of these waste drums. The measurement results and the estimated uncertainty will be presented. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Foster, LA (reprint author), Univ Calif Los Alamos Natl Lab, NMT-4, Los Alamos, NM 87544 USA. NR 7 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 0-8194-2997-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3536 BP 168 EP 175 DI 10.1117/12.339070 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology SC Instruments & Instrumentation; Nuclear Science & Technology GA BM50T UT WOS:000078921700017 ER PT J AU Maidak, BL Cole, JR Parker, CT Garrity, GM Larsen, N Li, B Lilburn, TG McCaughey, MJ Olsen, GJ Overbeek, R Pramanik, S Schmidt, TM Tiedje, JM Woese, CR AF Maidak, BL Cole, JR Parker, CT Garrity, GM Larsen, N Li, B Lilburn, TG McCaughey, MJ Olsen, GJ Overbeek, R Pramanik, S Schmidt, TM Tiedje, JM Woese, CR TI A new version of the RDP (Ribosomal Database Project) SO NUCLEIC ACIDS RESEARCH LA English DT Article ID MAXIMUM-LIKELIHOOD; DNA-SEQUENCES; TREES AB The Ribosomal Database Project (RDP-II), previously described by Maidak ef al. [Nucleic Acids Res. (1997), 25, 109-111], is now hosted by the Center for Microbial Ecology at Michigan State University. RDP-II is a curated database that offers ribosomal RNA (rRNA) nucleotide sequence data in aligned and unaligned forms, analysis services, and associated computer programs. During the past two years, data alignments have been updated and now include >9700 small subunit rRNA sequences. The recent development of an ObjectStore database will provide more rapid updating of data, better data accuracy and increased user access. RDP-II includes phylogenetically ordered alignments of rRMA sequences, derived phylogenetic trees, rRNA secondary structure diagrams, and various software programs for handling, analyzing and displaying alignments and trees. The data are available via anonymous ftp (ftp.cme.msu.edu) and WWW (http ://www.cme.msu.edu/RDP). The WWW server provides ribosomal probe checking, approximate phylogenetic placement of user-submitted sequences, screening for possible chimeric rRNA sequences, automated alignment, and a suggested placement of an unknown sequence on an existing phylogenetic tree. Additional utilities also exist at RDP-II, including distance matrix, T-RFLP, and a Java-based viewer of the phylogenetic trees that can be used to create subtrees. C1 Michigan State Univ, Dept Microbiol, E Lansing, MI 48824 USA. Michigan State Univ, Ctr Microbial Ecol, E Lansing, MI 48824 USA. Univ Illinois, Dept Microbiol, Urbana, IL 61801 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Michigan State Univ, Dept Comp Sci & Engn, E Lansing, MI 48824 USA. RP Maidak, BL (reprint author), Michigan State Univ, Dept Microbiol, 294 Giltner Hall, E Lansing, MI 48824 USA. RI Garrity, George/F-7551-2013; OI Garrity, George/0000-0002-4465-7034; Schmidt, Thomas/0000-0002-8209-6055 NR 6 TC 781 Z9 797 U1 2 U2 32 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD JAN 1 PY 1999 VL 27 IS 1 BP 171 EP 173 DI 10.1093/nar/27.1.171 PG 3 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 156CC UT WOS:000077983000042 PM 9847171 ER PT J AU Gelfand, MS Dubchak, I Dralyuk, I Zorn, M AF Gelfand, MS Dubchak, I Dralyuk, I Zorn, M TI ASDB: database of alternatively spliced genes SO NUCLEIC ACIDS RESEARCH LA English DT Article AB A database of alternatively spliced genes (ASDB) has been constructed based on (i) the results of the analysis of Swiss-Prot entries containing products of these genes and (ii) clustering procedure joining proteins that could arise by alternative splicing of the same gene. ASDB incorporates information about alternatively spliced genes, their products and expression patterns. It can be searched in order to find all products of alternative splicing produced in a particular tissue or a given organism, or all variants generated by a particular transcript. ASDB currently contains about 1700 protein sequences and can be accessed via the Internet at URL http://cbcg.nersc.gov/asdb. C1 Russian Acad Sci, Inst Prot Res, Pushchino 142292, Russia. Lawrence Berkeley Lab, Natl Energy Res Sci Comp Ctr, Berkeley, CA 94720 USA. RP Dubchak, I (reprint author), Russian Acad Sci, Inst Prot Res, Pushchino 142292, Russia. EM ildubchak@lbl.gov RI Gelfand, Mikhail/F-3425-2012 NR 8 TC 16 Z9 18 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD JAN 1 PY 1999 VL 27 IS 1 BP 301 EP 302 DI 10.1093/nar/27.1.301 PG 2 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 156CC UT WOS:000077983000080 PM 9847209 ER PT J AU Guo, DX AF Guo, DX TI A second order scheme for the Navier-Stokes equations: Stability and convergence SO NUMERICAL FUNCTIONAL ANALYSIS AND OPTIMIZATION LA English DT Article DE projection method; full discretization; Navier-Stokes equations; stability; convergence ID PROJECTION AB In this paper, a fully discretized projection method is introduced. It contains a parameter operator. Depending on this operator, we can obtain a first-order scheme, which is appropriate for theoretical analysis, and a second-order scheme, which is more suitable for actual computations. In this method, the boundary conditions of the intermediate velocity field and pressure are not needed. We give the proof of the stability and convergence for the first-order case. For the higher order cases, the proof were different, and we will present it elsewhere. In a forthcoming article [7], we apply this scheme to the driven-cavity problem and compare it with other schemes. C1 Oak Ridge Natl Lab, POB 2008,Bldg 6012,MS6367, Oak Ridge, TN 37831 USA. Indiana Univ, Dept Math, Bloomington, IN 47405 USA. Indiana Univ, Inst Sci Comp & Appl Engn, Bloomington, IN 47405 USA. NR 22 TC 3 Z9 3 U1 0 U2 0 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0163-0563 J9 NUMER FUNC ANAL OPT JI Numer. Funct. Anal. Optim. PY 1999 VL 20 IS 9-10 BP 881 EP 900 DI 10.1080/01630569908816929 PG 20 WC Mathematics, Applied SC Mathematics GA 263HR UT WOS:000084119700005 ER PT B AU Gropp, W AF Gropp, W BE Henderson, ME Anderson, CR Lyons, SL TI Exploiting existing software in libraries: Successes, failures, and reasons why SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn ID LINEAR ALGEBRA SUBPROGRAMS; SET AB The PETSc (Portable Extensible Tools for Scientific computing) library arose from research into domain decomposition methods which require combining many different solutions in a single application. The initial efforts tried to use existing numerical software but had limited success. The problems include everything from faulty assumptions about the computing environment (e.g., how many processes there are) to implicit (yet deadly) global state. More recently, PETSc and PVODE have found a way to cooperate, and new techniques that exploit dynamically linked libraries offer a more general approach to interoperable components. The paper highlights some of the issues in building sharable component software and discussing mistakes still often made in designing, maintaining, documenting, and testing components. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Gropp, W (reprint author), Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. NR 18 TC 1 Z9 1 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 21 EP 29 PG 9 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600004 ER PT B AU Cleary, A Kohn, S Smith, SG Smolinski, B AF Cleary, A Kohn, S Smith, SG Smolinski, B BE Henderson, ME Anderson, CR Lyons, SL TI Language interoperability mechanisms for high-performance scientific applications SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn AB Language interoperability is a difficult problem facing the developers and users of large numerical software packages. Language choices often hamper the reuse and sharing of numerical libraries, especially in a scientific computing environment that uses C, C++, Java, various Fortran dialects. and scripting languages such as Python. In this paper, we propose a new approach to language interoperability for high-performance scientific applications based on Interface Definition Language (IDL) techniques, We investigate the modifications necessary to adopt traditional IDL approaches for use by the scientific community, including IDL extensions for numerical computing and issues involved in mapping IDLs to Fortran 77 and Fortran 90. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. RP Cleary, A (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 30 EP 39 PG 10 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600005 ER PT B AU Balay, S Gropp, B McInnes, LC Smith, B AF Balay, S Gropp, B McInnes, LC Smith, B BE Henderson, ME Anderson, CR Lyons, SL TI A microkernel design for component-based parallel numerical software systems SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn AB What is the minimal software infrastructure and what type of conventions are needed to simplify development of sophisticated parallel numerical application codes using a variety of software components that are not necessarily available as source code? We propose an opaque object-based model where the objects are dynamically loadable from the file system of network. The microkernel required to manage such a system needs to include, at most a few basic services, namely, a mechanism for loading objects at run time via dynamic link libraries, and consistent schemes for error handling and memory management; and selected methods that all objects share, to deal with object life (destruction, reference counting, relationships), and object observation (viewing, profiling, tracing). We are experimenting with these ideas in the context of extensible numerical software within the ALICE (Advanced Large-scale Integrated Computational Environment) project, where se are building the microkernel to manage the interoperability among various tools for large-scale scientific simulations. This paper presents some preliminary observations and conclusions from our work with microkernel design. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Balay, S (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM balay@mcs.anl.gov; gropp@mcs.anl.gov; curfmann@mcs.anl.gov; bsmith@mcs.anl.gov NR 25 TC 0 Z9 0 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 58 EP 67 PG 10 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600008 ER PT B AU Hornung, RD Woodward, CS AF Hornung, RD Woodward, CS BE Henderson, ME Anderson, CR Lyons, SL TI An object-oriented approach for development and testing of parallel solution algorithms for nonlinear PDEs SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn ID SYSTEMS AB A flexible, object-oriented approach to the development of solution methods for nonlinear partial differential equations is presented. Flexibility is important in simulation codes because it allows application developers freedom to easily change key parts of solution algorithms and discretization schemes. New solver capabilities can also be added in the future. To achieve flexibility, careful attention is paid to the separation of algorithms, data, and problem description far ease in changing these components independently. Data structures are chosen so that each component works with data in a form best suited to its needs. Lastly, we discuss some consequences of the design. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Hornung, RD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 88 EP 96 PG 9 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600011 ER PT B AU Chow, E Cleary, AJ Falgout, RD AF Chow, E Cleary, AJ Falgout, RD BE Henderson, ME Anderson, CR Lyons, SL TI Design of the hypre preconditioner library SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn AB We discuss the design of hypre, an object-oriented library for the solution of large sparse linear systems on parallel computers. The mathematical emphasis of hypre is on modern powerful and scalable preconditioners. The design of hypre allows it to be used as both a solver package and a framework for algorithm development. The object model used for hypre is more general and flexible than the current generation of solver libraries. The design of hypre is proceeding in parallel with the standardization efforts of the DOE/academia Linear Equation Solver Interface forum. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Chow, E (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, POB 808,L-561, Livermore, CA 94551 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 106 EP 116 PG 11 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600013 ER PT B AU Hovland, P Norris, B Roh, L Smith, B AF Hovland, P Norris, B Roh, L Smith, B BE Henderson, ME Anderson, CR Lyons, SL TI Developing a derivative-enhanced object-oriented toolkit for scientific computations SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn ID AUTOMATIC DIFFERENTIATION AB We describe the development of a differentiated version of PETSc, an object-oriented toolkit for the parallel solution of scientific problems modeled by partial differential equations. Traditionally, automatic differentiation tools are applied to scientific applications to produce derivative-augmented code, which can then be used for sensitivity analysis, optimization, or parameter estimation. Scientific toolkits play an increasingly important role in developing large-scale scientific applications. By differentiating PETSc, we provide accurate derivative computations in applications implemented using the toolkit. In addition to using automatic differentiation to generate a derivative enhanced version of PETSc, we exploit the component-based organization of the toolkit, applying high-level mathematical insight to increase the accuracy and efficiency of derivative computations. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Hovland, P (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 129 EP 137 PG 9 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600015 ER PT B AU Freitag, L Jones, M Plassmann, P AF Freitag, L Jones, M Plassmann, P BE Henderson, ME Anderson, CR Lyons, SL TI Mesh component design and software integration within SUMAA3d SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn AB The requirements of distributed-memory applications that use mesh management software tools are diverse, and building software that meets these requirements represents a considerable challenge. In this paper we discuss design requirements for a general, component approach for mesh management for use within the context of solving PDE applications on parallel computers. We describe recent efforts with the SUMAAS3d package motived by a component-based approach and show how these efforts have considerably improved both the flexibility and the usability of this software. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Freitag, L (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 215 EP 224 PG 10 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600024 ER PT B AU Long, K Van Straalen, B AF Long, K Van Straalen, B BE Henderson, ME Anderson, CR Lyons, SL TI PDESolve: An object-oriented PDE analysis environment SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn AB PDESOLVE is a powerful C++ class library for rapidly and reliably setting up and solving advanced partial differential equations problems. PDESOLVE provides high-level objects for efficiently representing all the components of a numerical approximation to a PDE system, such as the equation itself, domain geometry, boundary conditions, discretisation method, and solution method. The design philosophy behind PDESOLVE is to provide a user syntax that mimics the mathematical description of a continuous PDE problem, allowing rapid translation of high-level mathematical problem descriptions into PDESOLVE programs. C1 Sandia Natl Labs, Livermore, CA 87185 USA. RP Long, K (reprint author), Sandia Natl Labs, Livermore, CA 87185 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 225 EP 234 PG 10 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600025 ER PT B AU Hornung, RD Kohn, SR AF Hornung, RD Kohn, SR BE Henderson, ME Anderson, CR Lyons, SL TI The use of object-oriented design patterns in the SAMRAI structured AMR framework SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn ID ADAPTIVE MESH REFINEMENT AB We describe the use of object-oriented design patterns in the implementation of a flexible framework for structured adaptive mesh refinement. We present five common patterns-Smart Pointers, Singleton, Abstract Factory, Strategy, and Chain of Responsibility-that have greatly simplified software development. These design patterns have enabled the decomposition of complex algorithms into smaller, more manageable, decoupled components that may be reused across a variety of applications. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Hornung, RD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. NR 15 TC 1 Z9 1 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 235 EP 244 PG 10 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600026 ER PT B AU Brown, DL Henshaw, WD Quinlan, DJ AF Brown, DL Henshaw, WD Quinlan, DJ BE Henderson, ME Anderson, CR Lyons, SL TI Overture: An object-oriented framework for serving partial differential equations on overlapping grids SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn AB The Overture framework is an object-oriented environment for solving partial differential equations in two and three space dimensions. It is a collection of C++ libraries that enables the use of finite difference and finite volume methods at a level that hides the details of the associated data structures. Overture can be used to solve problems in complicated, moving geometries using the method of overlapping grids. It merges geometry, grid generation, difference operators, boundary conditions, data-base access and graphics into an easy to use high level interface. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. RP Brown, DL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. NR 22 TC 6 Z9 6 U1 0 U2 1 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 245 EP 255 PG 11 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600027 ER PT B AU Cummings, JC Crotinger, JA Haney, SW Humphrey, WF Karmesin, SR Reynders, JVW Smith, SA Williams, TJ AF Cummings, JC Crotinger, JA Haney, SW Humphrey, WF Karmesin, SR Reynders, JVW Smith, SA Williams, TJ BE Henderson, ME Anderson, CR Lyons, SL TI Rapid application development and enhanced code interoperability using the POOMA framework SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn AB The Parallel Object-Oriented Methods and Applications (POOMA) Framework, written in ANSI/ISO C++, has demonstrated both great expressiveness and efficient code performance for large-scale scientific applications on computing platforms ranging from workstations to massively parallel supercomputers. The POOMA Framework provides high-level abstractions for multi-dimensional arrays, computational meshes, physical field quantities and collections of particles. POOMA also exploits advanced C++ programming techniques, such as expression templates and compile-time polymorphism, to optimise serial performance while encapsulating the details of parallel computation within a simple data-parallel array syntax. Consequently, scientists can quickly assemble parallel simulation codes without being bothered with the technical difficulties of parallel programming. The POOMA Framework is currently being used to develop application codes targeting several of the Department of Energy's Grand Challenge research areas. In addition, POOMA is providing infrastructure for one of the main code projects of the Accelerated Strategic Computing Initiative (ASCI) at Los Alamos National Laboratory. Work is now in progress on POOMA II, a complete rewrite of the POOMA Framework intended to increase expressiveness and code performance. In this presentation, we illustrate some of the successes of the POOMA approach in real-world scientific applications and highlight anticipated improvements in POOMA II. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cummings, JC (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 276 EP 285 PG 10 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600030 ER PT B AU Bassetti, F Davis, K Quinlan, D AF Bassetti, F Davis, K Quinlan, D BE Henderson, ME Anderson, CR Lyons, SL TI Optimizations for parallel object-oriented frameworks SO OBJECT ORIENTED METHODS FOR INTEROPERABLE SCIENTIFIC AND ENGINEERING COMPUTING, PROCEEDINGS SE SIAM PROCEEDINGS SERIES LA English DT Proceedings Paper CT SIAM Interdisciplinary Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing CY OCT 21-23, 1998 CL YORKTOWN HTS, NY SP SIAM, Natl Sci Fdn AB Application codes increasingly fail to realize the potential performance of modern parallel architectures; compilers have only limited mechanisms with which to effect sophisticated transformations to arrest this trend. Compilers must must perform optimizations in the context of the semantics of a complete language specification and thus cannot perform more sophisticated transformations. Object-oriented frameworks provide a level of tailoring of the C++ language to specific restricted contexts, but compilers are still relied upon for most performance optimization. No mechanism exists to express the restricted semantics of a class library such that a compiler could perform more sophisticated optimizations. In this paper we explore a family of optimizing transformations appropriate to object-oriented frameworks for scientific computing, and present a preprocessing mechanism, ROSE, which delivers the more Sophisticated transformations automatically from the use of abstractions represented within high level object-oriented frameworks. We have found that these optimizations permit improved performance over FORTRAN 77 by factors of three to four, sufficiently interesting to suggest that higher level abstractions can contain greater semantics and that the greater semantics can be used to drive more sophisticated optimizations than are possible with lower level languages. C1 Univ Calif Los Alamos Natl Lab, Sci Comp Grp CIC19, Los Alamos, NM 87544 USA. RP Bassetti, F (reprint author), Univ Calif Los Alamos Natl Lab, Sci Comp Grp CIC19, POB 1663, Los Alamos, NM 87544 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 0-89871-445-1 J9 SIAM PROC S PY 1999 BP 303 EP 312 PG 10 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN93H UT WOS:000083575600033 ER PT S AU Mohr, B Bassetti, F Davis, K Huttemann, S Launay, P Marinescu, DC Miller, DJ Vanderwart, RL Muller, M Prodan, A AF Mohr, B Bassetti, F Davis, K Huttemann, S Launay, P Marinescu, DC Miller, DJ Vanderwart, RL Muller, M Prodan, A BE Moreira, A Demeyer, S TI Parallel/high-performance object-oriented scientific computing SO OBJECT-ORIENTED TECHNOLOGY SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 13th European Conference on Object-Oriented Programming (ECOOP 99) CY JUN 14-18, 1999 CL LISBON, PORTUGAL SP Assoc Int Technol Objets, Air Portugal, IBM Corp, Univ Lisbon, Dept Comp Sci ID JAVA AB This chapter contains a summary of the presentations given at the Workshop on Parallei/High-Performance Object-Oriented Scientific Computing (POOSC'99) at the European Conference on Object-Oriented Programming (ECOOP'99) which was held in Lisbon, Portugal on June 15, 1999. The workshop was organized jointly by the Special Interest Group on Object-Oriented Technologies of the Esprit Working Group EuroTools and Los Alamos National Laboratory. C1 Forschungszentrum Julich, ZAM, Julich, Germany. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Tubingen, D-72074 Tubingen, Germany. IRISA, Rennes, France. Purdue Univ, Dept Comp Sci, W Lafayette, IN 47907 USA. Sandia Natl Labs, Livermore, CA 94550 USA. Ctr High Performance Comp, Stuttgart, Germany. Iuliu Hatieganu Univ, Cluj Napoca, Romania. RP Mohr, B (reprint author), Forschungszentrum Julich, ZAM, Julich, Germany. EM b.mohr@fz-juelich.de; fede@lanl.gov; kei@lanl.gv; hutteman@informatik.uni-tuebingen.de; Pascale.Launay@irisa.fr; dcm@cs.purdue.edu; djmille@sandia.gov; rlvande@sandia.gov; mueller@hlrs.de; aprodan@umfcluj.ro NR 18 TC 0 Z9 0 U1 1 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-66954-X J9 LECT NOTES COMPUT SC PY 1999 VL 1743 BP 222 EP 239 PG 18 WC Computer Science, Theory & Methods SC Computer Science GA BR07X UT WOS:000165599700013 ER PT S AU Tuch, DS Wedeen, VJ Dale, AM George, JS Belliveau, JW AF Tuch, DS Wedeen, VJ Dale, AM George, JS Belliveau, JW BE Chen, CT Lee, RC Shih, JX Zhong, MH TI Conductivity mapping of biological tissue using diffusion MRI SO OCCUPATIONAL ELECTRICAL INJURY: AN INTERNATIONAL SYMPOSIUM SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Article; Proceedings Paper CT 3rd International Conference on Electrical Injury and Safety CY OCT 26-28, 1998 CL SHANGHAI, PEOPLES R CHINA SP Univ Chicago, Elect Trauma Res Program, Shanghai Elect Power Hosp, China Burn Assoc, China Hydro Elect Power Med Sci Assoc, Cooper Bussmann, EI Dupont DeNemours & Co, US Electr Power Res Inst, Integra Lifesci, China Med Assoc, Shanghai Branch, Soc Phys regulat Biol & Med, US Natl Sci Fdn, Univ Chicago, Off Continuing Med Educ, Westaim Biomed Corp C1 Massachusetts Gen Hosp, Nucl Magnet Resonance Ctr, Charlestown, MA 02129 USA. MIT, Harvard Mit Div Hlth Sci & Technol, Cambridge, MA 02139 USA. MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Univ Calif Los Alamos Natl Lab, Biophys Grp, Los Alamos, NM USA. RP Tuch, DS (reprint author), Massachusetts Gen Hosp, Nucl Magnet Resonance Ctr, Charlestown, MA 02129 USA. RI Dale, Anders/A-5180-2010 NR 6 TC 51 Z9 54 U1 0 U2 4 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 EAST 63RD ST, NEW YORK, NY 10021 USA SN 0077-8923 BN 1-57331-232-0 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 1999 VL 888 BP 314 EP 316 DI 10.1111/j.1749-6632.1999.tb07965.x PG 3 WC Emergency Medicine; Public, Environmental & Occupational Health; Multidisciplinary Sciences; Rehabilitation SC Emergency Medicine; Public, Environmental & Occupational Health; Science & Technology - Other Topics; Rehabilitation GA BP20J UT WOS:000084392200031 PM 10842642 ER PT J AU Tittiranonda, P Burastero, S Rempel, D AF Tittiranonda, P Burastero, S Rempel, D TI Risk factors for musculoskeletal disorders among computer users SO OCCUPATIONAL MEDICINE-STATE OF THE ART REVIEWS LA English DT Article ID CARPAL-TUNNEL SYNDROME; CUMULATIVE TRAUMA DISORDERS; VIDEO DISPLAY TERMINALS; UPPER-EXTREMITY; CONSTRAINED POSTURES; OCCUPATIONAL FACTORS; OPERATING POSTURE; WORK POSTURE; SYMPTOMS; DISCOMFORT C1 Univ Calif Lawrence Livermore Natl Lab, Interdisciplinary Ergonom Res Program, Livermore, CA 94551 USA. Univ Calif San Francisco, Dept Med, Div Environm & Occupat Med, San Francisco, CA USA. RP Tittiranonda, P (reprint author), Univ Calif Lawrence Livermore Natl Lab, Interdisciplinary Ergonom Res Program, 7000 E Ave,L-723, Livermore, CA 94551 USA. RI Rempel, David/E-8424-2013 NR 73 TC 97 Z9 98 U1 2 U2 12 PU HANLEY & BELFUS INC PI PHILADELPHIA PA 210 S 13TH ST, PHILADELPHIA, PA 19107 USA SN 0885-114X J9 OCCUP MED JI Occup. Med.-State Art Rev. PD JAN-MAR PY 1999 VL 14 IS 1 BP 17 EP 38 PG 22 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 156ZT UT WOS:000078033900003 PM 9950008 ER PT B AU Crecelius, EA Lefkovitz, LF Cullinan, VI AF Crecelius, EA Lefkovitz, LF Cullinan, VI GP MTS MTS TI The sound is cleaner: A century of contaminant trends observed from dated cores SO OCEANS '99 MTS/IEEE : RIDING THE CREST INTO THE 21ST CENTURY, VOLS 1-3 LA English DT Proceedings Paper CT MTS/IEEE Conference on Riding the Crest Into the 21st Century (OCEANS 99) CY SEP 13-16, 1999 CL SEATTLE, WA SP Marine Technol Soc, Ocean Engn Soc, Inst Elect & Electr Engn ID CENTRAL PUGET SOUND; SEDIMENTS; PB-210; ACCUMULATION; MERCURY; RATES C1 Battelle Marine Sci Lab, Sequim, WA 98382 USA. RP Crecelius, EA (reprint author), Battelle Marine Sci Lab, 1529 W Sequim Bay Rd, Sequim, WA 98382 USA. NR 22 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC PI WASHINGTON PA 1828 L ST NW,SUITE 906, WASHINGTON, DC 20035 USA BN 0-933957-24-6 PY 1999 BP 1381 EP 1394 PG 4 WC Engineering, Marine; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA BP25F UT WOS:000084482300221 ER PT B AU Allen, BP Sharitz, RR AF Allen, BP Sharitz, RR BE Harmon, D TI Post-hurricane vegetation dynamics in old-growth forests of Congaree Swamp National Monument SO ON THE FRONTIERS OF CONSERVATION: PROCEEDINGS OF THE TENTH CONFERENCE ON RESEARCH AND RESOURCE MANAGEMENT IN PARKS AND ON PUBLIC LANDS LA English DT Proceedings Paper CT 10th Conference on Research and Resource Management in Parks and on Public Lands/George-Wright-Society Biennial Conference CY MAR 22-26, 1999 CL ASHEVILLE, NC SP George Wright Soc, US Natl Pk Serv, US Geol Survey, Biol Resources Div ID STANDS C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. NR 20 TC 3 Z9 3 U1 0 U2 1 PU GEORGE WRIGHT SOCIETY, INC. PI HANCOCK PA PO BOX 65, HANCOCK, MI 49930-0065 USA PY 1999 BP 306 EP 312 PG 7 WC Environmental Studies; Public Administration SC Environmental Sciences & Ecology; Public Administration GA BP35H UT WOS:000084811100053 ER PT J AU Kallio, M Rosa, CH AF Kallio, M Rosa, CH TI Large-scale convex optimization via saddle point computation SO OPERATIONS RESEARCH LA English DT Article AB This article proposes large-scale convex optimization problems to be solved via saddle points of the standard Lagrangian. A recent approach for saddle point computation is specialized, by way of a specific perturbation technique and unique scaling method, to convex optimization problems with differentiable objective and constraint functions. In each iteration the update directions for primal and dual variables are determined by gradients of the Lagrangian. These gradients are evaluated at perturbed points that are generated from current points via auxiliary mappings. The resulting algorithm suits massively parallel computing, though in this article we consider only a serial implementation. We test a version of our code embedded within GAMS on 16 nonlinear problems, which are mainly large. These models arise from multistage optimization of economic systems. For larger problems with adequate precision requirements, our implementation appears faster than MINOS. C1 Int Inst Appl Syst Anal, Laxenburg, Austria. Helsinki Sch Econ, Helsinki, Finland. Int Inst Appl Syst Anal, Laxenburg, Austria. Argonne Natl Lab, Argonne, IL 60439 USA. RP Kallio, M (reprint author), Int Inst Appl Syst Anal, Laxenburg, Austria. RI Kallio, Markku/G-2276-2013 NR 23 TC 5 Z9 5 U1 0 U2 4 PU INST OPERATIONS RESEARCH MANAGEMENT SCIENCES PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2909 USA SN 0030-364X J9 OPER RES JI Oper. Res. PD JAN-FEB PY 1999 VL 47 IS 1 BP 93 EP 101 DI 10.1287/opre.47.1.93 PG 9 WC Management; Operations Research & Management Science SC Business & Economics; Operations Research & Management Science GA 231QD UT WOS:000082320600010 ER PT S AU Bigio, IJ Mourant, JR Los, G AF Bigio, IJ Mourant, JR Los, G BE Bigio, IJ Schneckenburger, H Slavik, J Svanberg, K Viallet, PM Katzir, A TI Elastic-scattering spectroscopy for quantitative measurement of chemotherapy and PDT drug concentrations in vivo SO OPTICAL BIOPSIES AND MICROSCOPIC TECHNIQUES III, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Biopsies and Microscopic Techniques III CY SEP 09-11, 1998 CL STOCKHOLM, SWEDEN SP European Opt Soc, Soc Photo Opt Instrumentat Engineers, European Laser Assoc, Scandinavian Soc Laser Therapy, Int Biomed Opt Soc, Swedish Opt Soc, Commiss European Communities, Directorate Gen Sci Res & Dev DE optical diagnostics; noninvasive pharmacokinetics; elastic scattering; tissue spectroscopy; tissue optics; chemometrics; turbid media ID ABSORPTION AB We have applied elastic-scattering spectroscopy (ESS) for noninvasive, real-time in vivo measurement of the concentrations of certain drugs in tissue, utilizing a simple fiber-optic-probe spectroscopic system. The system uses a broadband light source, enabling the detection of compounds with absorption bands in most regions of the visible, as well as the NIR to 1700 nm. Subcutaneous tumors were grown in 4 Nude mice; the mice were treated with one of two chemotherapy agents, and the ESS system was used to perform pharmacokinetic measurements on the tumors following drug administration. Time histories of the drug concentrations in the tumors agreed with the known pharmacokinetics of the two drugs, and HPLC assays following sacrifice showed good correlation with the ESS values. Most photodynamic therapy agents and many chemotherapy drugs, including any that are not fluorescent, are ideal candidates for the ESS system. The measurement can be calibrated absolutely, and is not susceptible to problems associated with fluorescence assay methods. C1 Univ Calif Los Alamos Natl Lab, Biosci & Biotechnol Grp, Los Alamos, NM 87545 USA. RP Bigio, IJ (reprint author), Univ Calif Los Alamos Natl Lab, Biosci & Biotechnol Grp, MS-E535, Los Alamos, NM 87545 USA. NR 5 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 0-8194-3030-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3568 BP 26 EP 30 DI 10.1117/12.336840 PG 5 WC Engineering, Biomedical; Medicine, Research & Experimental; Optics SC Engineering; Research & Experimental Medicine; Optics GA BM51N UT WOS:000078935200004 ER PT S AU Steinkamp, JA Keij, JF AF Steinkamp, JA Keij, JF BE Farkas, DL Leif, RC Tromberg, BJ TI Elimination of light scatter interference in dual-laser flow cytometry by synchronous detection of emitted fluorescence: theory and demonstration using simulated signals SO OPTICAL DIAGNOSTICS AND LIVING CELLS II, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Diagnostics of Living Cells II CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE flow cytometry; synchronous detection; light scatter; background interference; phase-sensitive detection ID CELLS; RESOLUTION; PARTICLES AB Light scatter is often a source of interference in dual-laser excitation experiments by flow cytometry. If the two laser beams are not adequately separated or optical masking is not used, and if gated sequential fluorescence signal detection is not employed, light scatter from particles/cells as they pass across one beam can interfere in the fluorescence measurement channel of the other laser excitation beam. In this study we discuss the problem and present the theory for improving fluorescence measurements in dual-laser flow cytometry by use of modulated laser excitation and synchronous (phase-sensitive) detection of the resulting fluorescence emission to eliminate light scatter interference from particles/cells. fluorescence emission from particles/cells generated by the first laser beam (unmodulated cw) is measured using conventional means (detection channel no. 1). Light scatter interference from particles/cells as they pass across the first laser excitation beam, whose wavelength lies in the fluorescence measurement region of detection channel no. 2, is rejected by the synchronously tuned phase-sensitive channel no. 2 detector, whereas the fluorescence emission corresponding to laser no. 2 excitation is detected and measured. The efficacy of the technology in relation to analytical cytology measurements is demonstrated using simulated fluorescence and light scatter signals. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Steinkamp, JA (reprint author), Univ Calif Los Alamos Natl Lab, MS M888, Los Alamos, NM 87545 USA. NR 15 TC 1 Z9 1 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 0-8194-3074-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3604 BP 170 EP 176 DI 10.1117/12.349198 PG 7 WC Engineering, Biomedical; Medical Laboratory Technology; Microscopy; Optics SC Engineering; Medical Laboratory Technology; Microscopy; Optics GA BN19V UT WOS:000081053900018 ER PT S AU Weier, HUG Munne, S Lersch, RA Marquez, C Wu, J Pedersen, RA Fung, J AF Weier, HUG Munne, S Lersch, RA Marquez, C Wu, J Pedersen, RA Fung, J BE Farkas, DL Leif, RC Tromberg, BJ TI High performance analysis of single interphase cells with custom DNA probes spanning translocation breakpoints. SO OPTICAL DIAGNOSTICS AND LIVING CELLS II, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Diagnostics of Living Cells II CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE cytogenetics; DNA probes; translocations; domains; interphase cells; yeast artificial chromosomes; fluorescence in situ hybridization ID IN-SITU HYBRIDIZATION; INSITU HYBRIDIZATION; CHROMOSOME-ABNORMALITIES; HUMAN SPERM; EMBRYOS; FISH; ANEUPLOIDIES; DIAGNOSIS; CHILDREN AB The chromatin organization of interphase cell nuclei, albeit an object of intense investigation, is only poorly understood. In the past, this has hampered the cytogenetic analysis of tissues derived from specimens where only few cells were actively proliferating or a significant number of metaphase cells could be obtained by induction of growth. Typical examples of such hard to analyze cell systems are solid tumors, germ cells and, to a certain extent, fetal cells such as amniocytes, blastomeres or cytotrophoblasts. Balanced reciprocal translocations that do not disrupt essential genes and thus do not lead to disease symptoms exist in less than one percent of the general population. Since the presence of translocations interferes with homologue pairing in meiosis, many of these individuals experience problems in their reproduction, such as reduced fertility, infertility or a history of spontaneous abortions. The majority of translocation carriers enrolled in our in vitro fertilization (IVF) programs carry simple translocations involving only two autosomes. While most translocations are relatively easy to spot in metaphase cells, the majority of cells biopsied from embryos produced by IVF are in interphase and thus unsuitable for analysis by chromosome banding or FISH-painting. We therefore set out to analyze single interphase cells for presence or absence of specific translocations. Our assay, based on fluorescence in situ hybridization (FISH) of breakpoint-spanning DNA probes, detects translocations in interphase by visual microscopic inspection of hybridization domains. Probes are prepared so that they span a breakpoint and cover several hundred kb of DNA adjacent to the breakpoint. On normal chromosomes, such probes label a contiguous stretch of DNA and produce a single hybridization domain per chromosome in interphase cells. The translocation disrupts the hybridization domain and the resulting two fragments appear as physically separated hybridization domains in the nucleus. To facilitate the detection, DNA probes for breakpoints on different chromosomes are labeled in different colors, so the translocation event can be detected as a fusion of red and green hybridization domains. We applied this scheme successfully for the analysis of somatic and germ cells from more than 20 translocation patients, each with individual breakpoints, and provide summaries of our experience as well as strategies, cost and time frames to prepare case-specific translocation probes. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Subcellular Struct, Life Sci Div 74 157, Berkeley, CA 94720 USA. RP Weier, HUG (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Subcellular Struct, Life Sci Div 74 157, 1 Cyclotron Rd, Berkeley, CA 94720 USA. OI Munne, Santiago/0000-0002-1088-5565 NR 33 TC 1 Z9 1 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 0-8194-3074-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3604 BP 227 EP 236 DI 10.1117/12.349204 PG 10 WC Engineering, Biomedical; Medical Laboratory Technology; Microscopy; Optics SC Engineering; Medical Laboratory Technology; Microscopy; Optics GA BN19V UT WOS:000081053900024 ER PT S AU Deason, VA Telschow, KL Lassahn, GD Watson, SM Schley, RS AF Deason, VA Telschow, KL Lassahn, GD Watson, SM Schley, RS BE Cha, SS BryanstonCross, PJ Mercer, CR TI Real time imaging using the INEEL laser ultrasonic camera SO OPTICAL DIAGNOSTICS FOR FLUIDS/HEAT/COMBUSTION AND PHOTOMECHANICS FOR SOLIDS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Diagnostics for Fluids Heat Combustion and Photomechanics for Solids CY JUL 21-23, 1999 CL DENVER, CO SP SPIE DE ultrasonic; imaging; photorefractive; real-time; camera; lock-in AB A new approach to the measurement of ultrasonic vibrations has been developed at the INEEL. This system utilizes heterodyne interferometric detection in a photorefractive material to provide real time, full field images of ultrasonic vibration amplitude and phase without scanning. The INEEL Laser Ultrasonic Camera has linear response for ultrasonic displacements xi < lambda/4 pi or similar to 45 nm displacements at a laser wavelength of 532 nm. In addition, the system exhibits flat response and narrow band detection for a broad range of vibration frequencies (Hz to GHz). The system is very robust, and has the potential for operation even in noisy industrial settings. A description of the system, representative data and several potential applications will be presented. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Deason, VA (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RI Schley, Robert/B-9124-2017 OI Schley, Robert/0000-0001-8907-6535 NR 8 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 0-8194-3269-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3783 BP 144 EP 152 DI 10.1117/12.365769 PG 9 WC Instruments & Instrumentation; Mechanics; Materials Science, Characterization & Testing; Optics SC Instruments & Instrumentation; Mechanics; Materials Science; Optics GA BN97Z UT WOS:000083741900015 ER PT S AU Chow, R Ault, L Taylor, JR Jedlovec, D AF Chow, R Ault, L Taylor, JR Jedlovec, D BE Stahl, HP TI Thermally-induced distortion of a high average power laser system by an optical transport system SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE high power laser; absorptance; thermal lensing AB The atomic vapor laser isotope separation process uses high-average power lasers that have the commercial potential to enrich uranium for the electric power utilities. The transport of the laser beam through the laser system to the separation chambers requires high performance optical components, mast of which have either fused silica or Zerodur as the substrate material. One of the requirements of the optical components is to preserve the wavefront quality of the laser beam that propagate over long distances. Full aperture tests with the high power process lasers and finite element analysis (FEA) have been performed on the transport optics. The wavefront distortions of the various sections of the transport path were measured with diagnostic Hartmann sensor packages. The FEA results were derived from an in-house thermal-structural-optical code which is linked to the commercially available CodeV program. In comparing the measured and predicted results, the bulk absorptance of fused silica was estimated to about 50 ppm/cm in the visible wavelength regime. Wavefront distortions will be reported on optics made from fused silica and Zerodur substrate materials. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Chow, R (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 11 TC 1 Z9 1 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 246 EP 254 DI 10.1117/12.369190 PG 3 WC Optics SC Optics GA BP26G UT WOS:000084509400024 ER PT S AU Taylor, JR Chow, R Doss, FW Wong, JN AF Taylor, JR Chow, R Doss, FW Wong, JN BE Stahl, HP TI Performance and production requirements for the optical components in a high-average-power laser system SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE high-average-power laser; coating efficiency; absorption; optical components AB Optical components needed for high-average-power lasers, such as those developed for Atomic Vapor Laser Isotope Separation (AVLIS), require high levels of performance and reliability. Over the past two decades, optical component requirements for this purpose have been optimized, and performance and reliability have been demonstrated. Many of the optical components that are exposed to the high-power laser light affect the quality of the beam as it is transported through the system. The specifications for these optics, including a few parameters not previously reported and some component manufacturing and testing experience, are described. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Taylor, JR (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 12 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 255 EP 263 DI 10.1117/12.369191 PG 5 WC Optics SC Optics GA BP26G UT WOS:000084509400025 ER PT S AU Takacs, PZ Qian, SN Kester, T Li, HZ AF Takacs, PZ Qian, SN Kester, T Li, HZ BE Stahl, HP TI Large-mirror figure measurement by optical profilometry techniques SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE metrology; profilometry; large optics; x-ray mirrors; error sources; accuracy; repeatability ID LONG-TRACE-PROFILER; HEAT-LOAD MIRROR; DISTORTION PROFILE; PENTA-PRISM; LTP AB In most cases, conventional interferometric methods can be used to test the figure of large spherical and fat optical components. There are, however, certain types of unconventional surfaces, such as those used in grazing incidence x-ray applications, that are nearly impossible to test by conventional means. These cylindrical aspheres are usually tested by some type of scanning optical profiler. We discuss the use of a versatile slope measuring scanning interferometer system, the Long Trace Profiler (LTP), in measuring the figure error of large surfaces, particularly those that have extremely long radii of curvature in the tangential direction. Use of this instrument in different configurations has permitted measurements to be made on cylindrical asphere segments that are over one meter long, on water-cooled high beat load mirrors in ultra high vacuum synchrotron beam lines under actual operating conditions, and on complete x-ray telescope mirror shells and mandrels that are mounted in a vertical configuration to minimize gravity sag errors. Each of these different configurations has its own particular advantages and shortcomings. The ultimate performance of the LTP depends upon the thermal stability of the local environment. We illustrate the effects that temperature variations on the order of +/-0.1 degrees C have on the errors in the measurement of a long radius sphere. C1 Brookhaven Natl Lab, Instrumentat Div 535B, Upton, NY 11973 USA. RP Takacs, PZ (reprint author), Brookhaven Natl Lab, Instrumentat Div 535B, Upton, NY 11973 USA. NR 19 TC 9 Z9 9 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 266 EP 274 DI 10.1117/12.369192 PG 3 WC Optics SC Optics GA BP26G UT WOS:000084509400026 ER PT S AU Irick, S AF Irick, S BE Stahl, HP TI Long trace profiler survey results SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE Long Trace Profiler; LTP; round robin survey; mirror measurement AB Today the Long Trace Profiler (LTP) is widely accepted as a viable way to measure X-ray mirrors, and at some institutions is the only instrument available for measuring long, high-curvature aspheres. Although some questions of absolute accuracy over the entire LTP measurement range remain unanswered, a comparison of LTPs can still be made to assess measurement variation. Recently a round robin survey of some LTPs within the United States has been made using a single set of mirrors. These mirrors were used to characterize the performance of an LTP over its advertised range of operation. The results of this survey are presented here. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. RP Irick, S (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 9 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 275 EP 282 DI 10.1117/12.369237 PG 4 WC Optics SC Optics GA BP26G UT WOS:000084509400027 ER PT S AU Gaughan, R AF Gaughan, R BE Stahl, HP TI Visible light interferometer for EUVL system alignment SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE AB A visible wavelength interferometer has been developed for the alignment of an extreme ultraviolet lithography (EUVL) camera. Although the EUVL camera will operate at 13.4 nm, the alignment is far more conveniently done at visible wavelengths, at ambient pressure. Traditional visible interferometers are not capable of reaching the better than I nm accuracy required for EUVL camera alignment; so a phase shifting diffraction-limited interferometer was constructed and used to align and quantify the EUVL wavefront to an accuracy better than lambda visible/2000. The interferometer and alignment process are described, and camera wavefront measurements presented. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Gaughan, R (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-054,7000 East Ave, Livermore, CA 94550 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 390 EP 398 DI 10.1117/12.369216 PG 3 WC Optics SC Optics GA BP26G UT WOS:000084509400039 ER PT S AU Aikens, DM Bissinger, HD AF Aikens, DM Bissinger, HD BE Stahl, HP TI Overview of small optics for the national ignition facility SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE NIF; small optics; overview; components AB LLNL's project to construct the National Ignition Facility (NIF), a 192 beam laser system capable of generating enough Light energy necessary to achieve fusion ignition, will require 26,641 small optics, many of which will be supplied in the form of cleaned, tested and aligned assemblies. These assemblies will be built to print, cleaned to specifications, and tested to performance specifications, ready to be installed in the laser system. A wide range of potential suppliers will participate in the manufacture of these sophisticated opto-mechanical systems. The injection laser system requires 7,440 precision optical components manufactured to state of the art performance specifications. In addition to 550 aspheric lenses, almost 2,000 precision spherical elements are required. Wave-fronts are specified in terms of P-V, RMS and RMS Gradient wave-front error, with strict requirements on the filtering and resolution which is required. Precision polarizers, high reflectors, Leaking mirrors, high damage threshold coatings and cleanliness levels of 50 to 100 are also specified for this section of the NIF laser. The alignment and diagnostics systems for the NIF require 19,201 optics, many of which have requirements that exceed those of the injection laser system. All of these optics will be purchased using the ISO 10110 drawing notations. Other sections of the laser system will utilize commercial, off the shelf components to control cost. This paper will give an overview of the project and its objectives, with specific attention to the small optics required for the NIF. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Aikens, DM (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-495, Livermore, CA 94550 USA. NR 9 TC 1 Z9 1 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 476 EP 487 DI 10.1117/12.369227 PG 2 WC Optics SC Optics GA BP26G UT WOS:000084509400049 ER PT S AU Laumann, CW Korniski, RJ AF Laumann, CW Korniski, RJ BE Stahl, HP TI NIF optical systems design, preamplifier beam transport system opto-mechanical design SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE NIF; relay telescope; pupil relay; beam timing AB The Injection Laser System (ILS) optical design of the National Ignition Facility (NLF) laser system is described, covering design functions, requirements and constraints, various approaches and options, and the resultant configuration. The front end compromises approximately 70 optical elements per beamline, and 8300 elements total, whose characteristic dimensions are from two to six inches. Individual beamlines span a distance of approximately 15 meters. A variety of optical element types are used: spherical and aspheric lenses, mirrors, polarizers, multi-order waveplates, Faraday rotators, and laser rods. The front end performs multiple functions, namely to: image the pupil of the NIF laser system; amplify the beam's energy with a gain of approximately 10(4); magnify the beam size by 30x; split the beam four-fold; provide back-reflection isolation; and adjust the pupil location, along with arrival time of the pulse, on a beam-by-beam basis. Due to the high-energy nature of the beam, particular attention is paid to minimizing peak fluence throughout the system, thus reducing the likelihood of optical damage. The front end must deliver a wavefront with no more than approximately a wave of P-V aberration (at 1.053 um). This demanding wavefront requirement requires optics' surfaces and transmitted wavefronts to be of relatively high quality, typically 1/10 wave P-V (at 0.633um). C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Laumann, CW (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-490, Livermore, CA 94550 USA. NR 3 TC 3 Z9 3 U1 1 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 488 EP 495 DI 10.1117/12.369228 PG 2 WC Optics SC Optics GA BP26G UT WOS:000084509400050 ER PT S AU Boyd, RD Bliss, ES Boege, SJ Demaret, RD Feldman, M Gates, AJ Holdener, FR Hollis, J Knopp, CF McCarville, TJ Miller-Kamm, VJ Rivera, WE Salmon, JT Severyn, JR Thompson, CE Wang, DY Zacharias, RA AF Boyd, RD Bliss, ES Boege, SJ Demaret, RD Feldman, M Gates, AJ Holdener, FR Hollis, J Knopp, CF McCarville, TJ Miller-Kamm, VJ Rivera, WE Salmon, JT Severyn, JR Thompson, CE Wang, DY Zacharias, RA BE Stahl, HP TI Alignment and diagnostics on the National Ignition Facility laser system SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE AB The NIF laser system will be capable of delivering 1.8MJ of 351nm energy in 192 beams. Diagnostics instruments must measure beam energy, power vs. time, wavefront quality, and beam intensity profile to characterize laser performance. Alignment and beam diagnostics are also used to set the laser up for the high power shots and to isolate problems when performance is less than expected. Alignment and beam diagnostics are multiplexed to keep the costs under control. At the front-end the beam is aligned and diagnosed in an input sensor package. The output 1053nm beam is sampled by collecting a 0.1% reflection fi-om an output beam sampler and directing it to the output sensor package (OSP). The OSP also gets samples from final focus lens reflection and samples from the transport spatial filter pinhole plane. The output 351nm energy is measured by a calorimeter collecting the signal from an off-axis diffractive beam-sampler. Detailed information on the focused beam in the high-energy target focal plane region is gathered in the precision diagnostics. This paper describes the design of the alignment and diagnostics on the NIF laser system. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Boyd, RD (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-495, 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 496 EP 501 DI 10.1117/12.369229 PG 2 WC Optics SC Optics GA BP26G UT WOS:000084509400051 ER PT S AU Wang, DY English, RE Aikens, DM AF Wang, DY English, RE Aikens, DM BE Stahl, HP TI Implementation of ISO 10110 optics drawing standards for the National Ignition Facility SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE optics drawings; ISO 10110; National Ignition Facility (NIF) AB The National Ignition Facility (NIF) project elected to implement ISO 10110 standard for the specifications of NIF optics drawings in 1996. More than 7,000 NIF large optics and 20,000 NIF small optics will be manufactured based on ISO 10110 indications. ISO 10110 standard meets many of the needs of the NIF optics specifications. It allows the optical engineer to quantify and clearly communicate the desired optical specifications. While no single drawing standard specifies all the requirements of high energy laser system, a combination of ISO 10110 standard with detailed notes make it possible to apply international drawing standards to the NIF laser system. This paper will briefly describe LLNL's interpretation and implementation of the ISO 10110 drawing standard, present some examples of NIF optics drawings, and discuss pros and cons of the indications from the perspective of this application. Emphasis will be given to the surface imperfection specifications, known as 5/, for the NIF optics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Wang, DY (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-495, Livermore, CA 94551 USA. NR 8 TC 2 Z9 3 U1 4 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 502 EP 508 DI 10.1117/12.369230 PG 3 WC Optics SC Optics GA BP26G UT WOS:000084509400052 ER PT S AU Lawson, JK Aikens, DM English, RE Whistler, WT House, W Nichols, MA AF Lawson, JK Aikens, DM English, RE Whistler, WT House, W Nichols, MA BE Stahl, HP TI Surface figure and roughness tolerances for NIF optics and the interpretation of the gradient, P-V wavefront and RMS specifications SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE P-V wavefront; RMS measurements; gradient NIF optics; ISO 10110; specifications; surface figure; RMS; gradient; wavefront AB In a high energy laser system such as the National Ignition Facility (NIF), the ability to focus light into as small a spot as possible at the highest possible fluence is highly dependent on the quality of the optics used in the system. Typically, surface form errors and transmitted and reflected wavefront errors are specified in terms of a peak-to-valley wavefront error (P-V), or occasionally in terms of an RMS wavefront error (RMS)(1). It has been shown, however, that the parameter that most closely correlates with beam focusability is neither of these, but the RMS of the gradients of the wavefront error (RMS Gradient)(2). Further, the spatial frequency of the wavefront error plays a significant role in the way that a given error effects the performance of the laser system, so careful attention must be paid to how the spatial filtering is both specified and accomplished. Since ISO 10110 has no specific provisions for a gradient specification, LLNL has developed its own notation and procedures for these critical specifications. In evaluating surface figure errors as specified by the NIF drawings, modern phase modulating interferometers (PMI) will be used. In addition to performing QA testing of the optics, LLNL intends to utilize the software capabilities of the instruments to obtain the information to model the wavefront of the 131 passes through various optical elements comprising the NIF "front end"(3). A typical transmitted wavefront error call-out for an optic in the front end is: lambda/8 P-V, lambda/40 RMS, lambda/30/ cm RMS gradient, with these values evaluated for spatial periods >2mm only. Tests will be performed and documented after coating and as installed in the specified mechanical mounts. This paper describes the evaluation of the wavefront error for NIF small optics including specifications over a given spatial period call-out, the proper low pass filtering of the data and the allowable filtering and settings that can be applied to obtain proper wavefront data. This paper also describes the origin and evolution of other NIF wavefront and roughness specifications, and gives examples. Since the wavefront requirements and hence the specifications vary for the different systems in the NIF, we will focus on one system, the injection laser system (ILS) or "front end". Also discussed will be the metrology and data manipulation requirements for the large aperture optics. Finally, clarification will be given to the differences between various versions of the RMS wavefront and roughness specifications allowed in ISO 10110, and how they contrast to the RMS roughness specifications used in ANSI-Y14.5. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Lawson, JK (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 7 TC 17 Z9 18 U1 0 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 510 EP 517 DI 10.1117/12.369231 PG 6 WC Optics SC Optics GA BP26G UT WOS:000084509400053 ER PT S AU Sheehan, L Hendrix, JL Battersby, C Oberhelman, S AF Sheehan, L Hendrix, JL Battersby, C Oberhelman, S BE Stahl, HP TI National Ignition Facility small optics laser-induced damage and photometry measurements program SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE optical coatings; qualification; specifications; laser-induced damage; photometry; ratio reflectometry AB The National Ignition Facility will require upwards of 25,000 small optical components in its various beam conditioning and diagnostic packages. A quality control program designed to ensure that the elements meet the required specifications will test these optical elements. For many of the components, damage performance is one of the critical specifications, which will require state-of-the-art performance from the industry participants. A program was initiated to understand the current performance level of such optics. The results of this study as it pertains to laser-induced damage is shown. The use of ratio reflectometry is also addressed as the method of choice for photometry measurements on these industry supplied optics. 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 3 TC 4 Z9 4 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 518 EP 524 DI 10.1117/12.369232 PG 3 WC Optics SC Optics GA BP26G UT WOS:000084509400054 ER PT S AU Stowers, IF AF Stowers, IF BE Stahl, HP TI Optical cleanliness specifications and cleanliness verification SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE cleanliness; aerosols; cleanroom; particulate settling; light scattering; beam obscuration AB Optical cleanliness is important to NIF because it results in beam obscuration and scatter losses which occur in the front-end (containing over 20,000 small optics) and the large-aperture portions of the laser (containing approximate to 7,300 optics in 192 beamlines). The level of particulate cleanliness necessary for MF, is similar to the scatter loss due to surface roughness. That is, the scatter loss should not exceed less than or equal to 2.5x10(-5) per surface. Establishing requirements for optical and structural surface cleanliness needs consideration of both particulate and organic thin-film cleanliness. Both forms of cleanliness may be specified using guidelines specified in Military Standard 1246C and are referred to as cleanliness Levels. This Military Standard is described briefly and displayed in tables and charts. The presence of organic thin-films on structural surfaces is of particular concern if the contaminated surface is near solgel coated optics (solgel coatings provide an antireflection (AR) quality); or the optic is in a vacuum. In a vacuum, organic contaminant molecules have a much high probability of transporting from their source to a solgel-coated optic and thereby result in the rapid change in the transmission of the antireflection coating. Optical surface cleanliness can be rapidly degraded if a clean optic is exposed to any atmosphere containing an aerosol of small particles. The use of cleanrooms, as described in Federal Standard 209C, minimizes the settling of particulate contaminants and is described using charts and tables. These charts assist in determining the obscuration and scatter loss that can be expected when a clean surface is exposed to various Classes of cleanrooms due to particulate settling. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Stowers, IF (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,MS L-495, Livermore, CA 94550 USA. NR 5 TC 3 Z9 4 U1 0 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 525 EP 530 DI 10.1117/12.369233 PG 4 WC Optics SC Optics GA BP26G UT WOS:000084509400055 ER PT S AU McCarville, TJ AF McCarville, TJ BE Stahl, HP TI NIF small mirror mounts SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP McCarville, TJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-490, Livermore, CA 94550 USA. NR 0 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 531 EP 536 DI 10.1117/12.369235 PG 4 WC Optics SC Optics GA BP26G UT WOS:000084509400056 ER PT S AU Simon, T House, W AF Simon, T House, W BE Stahl, HP TI Opto-mechanical assembly procurement for the national ignition facility SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE opto-mechanical; assembly; NIF; packaging; shipping; specifications; procurement; MIL-STD-1246C; surface cleanliness AB A large number of the small optics procurements for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) will be in the form of completely assembled, tested, and cleaned subsystems. These subsystems will be integrated into the NIF at LLNL. To accomplish this task, the procurement packages will include, optical and mechanical drawings, acceptance test and cleanliness requirements. In January 1999, the first such integrated opto-mechanical assembly was received and evaluated at LLNL. With the successful completion of this important trial procurement, we were able to establish the viability of purchasing clean, ready to install, opto-mechanical assemblies from vendors within the optics industry. 32 vendors were chosen from our supplier database for quote, then five were chosen to purchase from. These five vendors represented a cross section of the optics industry. From a "value" catalog supplier (that did the whole job internally) to a partnership between three specialty companies, these vendors demonstrated they have the ingenuity and capability to deliver cost competitive, MF-ready, optomechanical assemblies. This paper describes the vendor selection for this procurement, technical requirements including packaging, fabrication, coating, and cleanliness specifications, then testing and verification. It also gives real test results gathered from inspections performed at LLNL that show how our vendors scored on the various requirements. C1 Univ Calif Lawrence Livermore Natl Lab, Natl Ignit Facil Project, Livermore, CA 94550 USA. RP Simon, T (reprint author), Univ Calif Lawrence Livermore Natl Lab, Natl Ignit Facil Project, MS-487, Livermore, CA 94550 USA. NR 9 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 537 EP 543 DI 10.1117/12.369236 PG 3 WC Optics SC Optics GA BP26G UT WOS:000084509400057 ER PT S AU Qian, SA Sostero, G Takacs, PZ AF Qian, SA Sostero, G Takacs, PZ BE Stahl, HP TI Precision calibration and systematic error reduction in the Long Trace Profiler SO OPTICAL MANUFACTURING AND TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optical Manufacturing and Testing III CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE Long Trace Profiler; LTP; calibration; angle calibration; accuracy; system error; focal error ID HEAT-LOAD MIRROR; DISTORTION PROFILE; PENTA-PRISM; LTP AB The Long Trace Profiler has become the instrument of choice for minor surface figure test and slope error measurement of synchrotron radiation and x-ray astronomy optics. In order to achieve highly accurate measurements with the LTP, systematic errors need to be reduced by precise angle calibration and accurate focal plane position adjustment. A self-scanning method is presented to adjust the focal plane position of the detector with high precision by use of a pentaprism scanning technique. The focal plane position can be set to better than 0.25 mm for a 1250 mm focal length FT lens using this technique. The use of a 0.03 are second resolution theodolite coupled with the sensitivity of the LTP detector system can be used to calibrate angular linearity error very precisely. Some suggestions are introduced for reducing the system error. With these precision calibration techniques, accuracy in the measurement of figure and slope error on meter-long mirrors is now at a level of about 1 mu rad rms within whole testing range of the LTP. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Qian, SA (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 23 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 0-8194-3268-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3782 BP 627 EP 636 DI 10.1117/12.369239 PG 4 WC Optics SC Optics GA BP26G UT WOS:000084509400068 ER PT S AU Demos, SG Radousky, HB Alfano, RR AF Demos, SG Radousky, HB Alfano, RR BE Chance, B Alfano, RR Tromberg, BJ Katzir, A TI Subsurface imaging using the spectral polarization difference technique and NIR illumination SO OPTICAL TOMOGRAPHY AND SPECTROSCOPY OF TISSUE III, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Tomography and Spectroscopy of Tissue III CY JAN 24-28, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE polarization; tissues; light scattering; imaging ID FLUORESCENCE MICROSCOPY; TISSUE AB A subsurface imaging system is utilized to test the ability of the spectral polarization difference imaging technique for deep subsurface imaging in tissues. The illumination of the system is derived from compact class In lasers in the red and NIR spectral region and, alternatively, from a white light source and selection of the appropriate illumination wavelength using band-pass optical filters. The experimental results demonstrate detection and imaging of a high-scattering object located up to 1.5 cm underneath the surface of a host chicken tissue. 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 8 TC 1 Z9 1 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 0-8194-3067-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3597 BP 406 EP 410 DI 10.1117/12.356824 PG 5 WC Engineering, Biomedical; Optics SC Engineering; Optics GA BN68N UT WOS:000082585500045 ER PT S AU Guo, Y Savage, HE Liu, F Schantz, SP Ho, PP Alfano, RR AF Guo, Y Savage, HE Liu, F Schantz, SP Ho, PP Alfano, RR BE Chance, B Alfano, RR Tromberg, BJ Katzir, A TI Subsurface structure of tissues investigated by noninvasive optical second harmonic tomography SO OPTICAL TOMOGRAPHY AND SPECTROSCOPY OF TISSUE III, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Tomography and Spectroscopy of Tissue III CY JAN 24-28, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE second harmonic generation; optical tomography; histology AB Second harmonic imaging was used to evaluate the subsurface layer structure of hamster cheek pouch mucosal tissues using femtosecond laser technology. Two dimensional images of hamster cheek pouch mucosa were obtained by scanning the second harmonic signal at various lateral and axial positions. The spatial mapping of the second harmonic signals showed depth differentiation between different tissue lavers. C1 CUNY City Coll, Dept Elect Engn, DOE Ctr Excellence Laser Imaging & Canc Diagnost, Inst Ultrafast Spect & Lasers, New York, NY 10031 USA. RP Guo, Y (reprint author), CUNY City Coll, Dept Elect Engn, DOE Ctr Excellence Laser Imaging & Canc Diagnost, Inst Ultrafast Spect & Lasers, New York, NY 10031 USA. NR 4 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 0-8194-3067-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3597 BP 480 EP 482 DI 10.1117/12.356846 PG 3 WC Engineering, Biomedical; Optics SC Engineering; Optics GA BN68N UT WOS:000082585500055 ER PT J AU Banks, PS Feit, MD Perry, MD AF Banks, PS Feit, MD Perry, MD TI High-intensity third-harmonic generation in beta barium borate through second-order and third-order susceptibilities SO OPTICS LETTERS LA English DT Article ID BETA-BAB2O4; PULSES AB The azimuthal dependence of third-order and cascaded second-order nonlinear coupling was used to measure the relative contributions of each to direct third-harmonic generation in beta-barium borate. This permitted the measurement of the values of tensor elements chi(10)((3)), chi(11)((3)), and chi(16)((3)) relative to the known chi(ij)((2)). Finally, conversion efficiencies to 3 omega of up to 6% were achieved with a femtosecond chirped-pulse amplification laser with 200 GW/cm(2) in collimated beams. (C) 1999 Optical Society of America. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Banks, PS (reprint author), Lawrence Livermore Natl Lab, L-477,POB 808, Livermore, CA 94550 USA. EM pbanks@llnl.gov RI Feit, Michael/A-4480-2009 NR 13 TC 40 Z9 40 U1 2 U2 13 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD JAN 1 PY 1999 VL 24 IS 1 BP 4 EP 6 DI 10.1364/OL.24.000004 PG 3 WC Optics SC Optics GA 155MZ UT WOS:000077952100002 PM 18071389 ER PT J AU Wagner, GJ Carrig, TJ Page, RH Schaffers, KI Ndap, JO Ma, XY Burger, A AF Wagner, GJ Carrig, TJ Page, RH Schaffers, KI Ndap, JO Ma, XY Burger, A TI Continuous-wave broadly tunable Cr2+: ZnSe laser SO OPTICS LETTERS LA English DT Article ID ZINC CHALCOGENIDES; MU-M; EFFICIENT AB We report room-temperature operation of an all-solid-state broadly tunable continuous-wave Cr2+:ZnSe laser. Output power of 250 mW, an absorbed power slope efficiency of 63%, and continuous tunability from 2138 to 2760 nm are demonstrated. (C) 1999 Optical Society of America. C1 Coherent Technol Inc, Lafayette, CO 80026 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Fisk Univ, Ctr Photon Mat & Devices, Nashville, TN 37208 USA. RP Wagner, GJ (reprint author), Coherent Technol Inc, 655 Aspen Ridge Dr, Lafayette, CO 80026 USA. RI Wagner, Gregory/I-4377-2015 NR 12 TC 145 Z9 147 U1 2 U2 29 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD JAN 1 PY 1999 VL 24 IS 1 BP 19 EP 21 DI 10.1364/OL.24.000019 PG 3 WC Optics SC Optics GA 155MZ UT WOS:000077952100007 PM 18071394 ER PT J AU Fleming, JG Lin, SY AF Fleming, JG Lin, SY TI Three-dimensional photonic crystal with a stop band from 1.35 to 1.95 mu m SO OPTICS LETTERS LA English DT Article ID GAP; MICROSTRUCTURES AB A combination of advanced silicon-processing techniques was used to create three-dimensional (3D) photonic crystals with a 180-nm minimum feature size. The resulting 3D crystal displayed a strong stop band at optical wavelengths from lambda = 1.35 mu m to lambda = 1.95 mu m. This is believed to be the smallest 3D crystal with a complete 3D photonic bandgap ever created. (C) 1999 Optical Society of America. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Fleming, JG (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 14 TC 255 Z9 261 U1 1 U2 15 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD JAN 1 PY 1999 VL 24 IS 1 BP 49 EP 51 DI 10.1364/OL.24.000049 PG 3 WC Optics SC Optics GA 155MZ UT WOS:000077952100017 PM 18071404 ER PT J AU Czyzyk, J Mehrotra, S Wagner, M Wright, SJ AF Czyzyk, J Mehrotra, S Wagner, M Wright, SJ TI PCx: An interior-point code for linear programming SO OPTIMIZATION METHODS & SOFTWARE LA English DT Article DE linear programming; interior-point methods; software ID FACTORIZATION; ELIMINATION; ALGORITHM AB We describe the code PCx, a primal-dual interior-point code for linear programming. Information is given about problem formulation and the underlying algorithm, along with instructions for installing, invoking, and using the code. Computational results on standard test problems are reported. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Wroclawska Szkola Jezykowa, PL-54217 Wroclaw, Poland. Northwestern Univ, Dept Ind Engn & Management Sci, Evanston, IL 60208 USA. Cornell Univ, Sch Ind Res & Ind Engn, Ithaca, NY 14850 USA. RI Mehrotra, Sanjay/B-7477-2009; Wagner, Michael/A-4649-2011; Wagner, Michael/E-6273-2016 OI Wagner, Michael/0000-0003-3421-4763 NR 18 TC 33 Z9 36 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 1055-6788 J9 OPTIM METHOD SOFTW JI Optim. Method Softw. PY 1999 VL 11-2 IS 1-4 SI SI BP 397 EP 430 DI 10.1080/10556789908805757 PG 34 WC Computer Science, Software Engineering; Operations Research & Management Science; Mathematics, Applied SC Computer Science; Operations Research & Management Science; Mathematics GA 296NZ UT WOS:000086031600014 ER PT S AU Barraza, J Shu, DM Kuzay, T Royston, TJ AF Barraza, J Shu, DM Kuzay, T Royston, TJ BE Derby, EA Gordon, CG Vukobratovich, D Yoder, PR Zweben, C TI Vibratory response modeling and verification of a high-precision optical positioning system SO OPTOMECHANICAL ENGINEERING AND VIBRATION CONTROL SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optomechanical Engineering and Vibration Control CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE vibration isolation; positioning stability; vibratory-response modeling ID ADVANCED PHOTON SOURCE AB A generic vibratory-response modeling program has been developed as a tool for designing high-precision optical positioning systems. Based on multibody dynamics theory, the system is modeled as rigid-body structures connected by linear elastic elements, such as complex actuators and bearings. The full dynamic properties of each element are determined experimentally or theoretically, then integrated into the program as inertial and stiffness matrices. Utilizing this program, the theoretical and experimental verification of the vibratory behavior of a double-multilayer monochromator support and positioning system is presented Results of parametric design studies that investigate the influence of support floor dynamics and highlight important design issues are also presented. Overall, good matches between theory and experiment demonstrate the effectiveness of the program as a dynamic modeling tool. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Barraza, J (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 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 0-8194-3272-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3786 BP 86 EP 97 PG 12 WC Acoustics; Engineering, Mechanical; Instruments & Instrumentation; Materials Science, Composites; Optics SC Acoustics; Engineering; Instruments & Instrumentation; Materials Science; Optics GA BN92H UT WOS:000083488000009 ER PT J AU Clifford, DJ Hatcher, PG Botto, RE Muntean, JV Anderson, KB AF Clifford, DJ Hatcher, PG Botto, RE Muntean, JV Anderson, KB TI The nature and fate of natural resins in the geosphere. IX Structure and maturation similarities of soluble and insoluble polylabdanoids isolated from Tertiary Class I resinites SO ORGANIC GEOCHEMISTRY LA English DT Article ID NMR-SPECTROSCOPY; C-13 NMR; PYROLYSIS; CLASSIFICATION; SEQUENCE; WALTZ-16; AMBERS AB Soluble polylabdanoids were isolated from five Tertiary Class I resinites by sequential extraction and were characterized by C-13 and H-1 NMR spectroscopy and Py-GC-MS. The structure and maturation characteristics of soluble extracts were strikingly similar to those observed for polylabdanoids in the native resinite. Soluble and insoluble materials undergo parallel geotransformation processes similar to those observed previously, including (i) exomethylene and total olefinic carbon depletion, (ii) double bond redistribution as indicated by Sigma C-14/Sigma C-15 pyrolysis product ratios and (iii) A-ring defunctionalization. Resonances at 138 and 127 ppm in C-13 NMR spectra were shown to be those of aromatic and olefinic structures in mature samples, indicating that double bond content had been overestimated in the past. Proton NMR analyses have revealed several structural features previously unobserved, Resonances at 5.3 ppm of mature polymers were assigned to trisubstituted olefins in cyclized/cross-linked polylabdanoids. Further evidence in support of this pathway is derived from C-13 NMR spectra, from which an increase in aliphatic carbon content paralleling the loss of olefinic structures was observed. (C) 1999 Published by Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Penn State Univ, Fuel Sci Program, University Pk, PA 16802 USA. RP Clifford, DJ (reprint author), Energy Inst, Acad Projects, University Pk, PA 16802 USA. NR 29 TC 16 Z9 17 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0146-6380 J9 ORG GEOCHEM JI Org. Geochem. PY 1999 VL 30 IS 7 BP 635 EP 650 DI 10.1016/S0146-6380(99)00018-2 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 223JY UT WOS:000081839000012 ER PT J AU Dayan, H Abrajano, T Sturchio, NC Winsor, L AF Dayan, H Abrajano, T Sturchio, NC Winsor, L TI Carbon isotopic fractionation during reductive dehalogenation of chlorinated ethenes by metallic iron SO ORGANIC GEOCHEMISTRY LA English DT Article DE halogenated solvents; chlorinated ethenes; stable carbon isotopes; compound-specific isotope analysis; gas chromatography : combustion : isotope ratio mass spectrometry ID DEGRADATION AB Highly chlorinated ethenes are resilient under aerobic conditions, but are known to degrade in reducing systems through biotic and abiotic reductive dehalogenation. Reductive dehalogenation of chlorinated ethenes by zero valent iron was recently shown to occur in both natural and engineered systems. The study reported in this paper was aimed at determining the magnitude and direction of the carbon isotopic fractionation of chlorinated ethenes during reductive dehalogenation by metallic iron. Large isotopic shifts were observed during the reaction duration for each of the solvents, where delta(13)C values of PCE, TCE and c-DCE shifted by 24 parts per thousand, 12 parts per thousand and 24 parts per thousand, respectively, after 80-90% consumption. The fact that these large changes in isotopic composition can occur during reductive dehalogenation has significant implications for monitoring the progress of zero valent iron remediation, and perhaps other remediation technologies. If chlorinated ethenes from contaminated sites can be analyzed for carbon isotope composition at any given point of an engineered remediation program, our results indicate that the efficacy of remediation can be assessed quantitatively. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Rensselaer Polytech Inst, Dept Earth & Environm Sci, Troy, NY 12180 USA. Mem Univ Newfoundland, Dept Earth Sci, St Johns, NF A1B 3X5, Canada. Mem Univ Newfoundland, Environm Sci Programme, St Johns, NF A1B 3X5, Canada. Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. RP Abrajano, T (reprint author), Rensselaer Polytech Inst, Dept Earth & Environm Sci, Troy, NY 12180 USA. NR 12 TC 57 Z9 61 U1 3 U2 17 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0146-6380 J9 ORG GEOCHEM JI Org. Geochem. PY 1999 VL 30 IS 8A BP 755 EP 763 DI 10.1016/S0146-6380(99)00058-3 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 238NC UT WOS:000082715500004 ER PT J AU Huang, L Sturchio, NC Abrajano, T Heraty, LJ Holt, BD AF Huang, L Sturchio, NC Abrajano, T Heraty, LJ Holt, BD TI Carbon and chlorine isotope fractionation of chlorinated aliphatic hydrocarbons by evaporation SO ORGANIC GEOCHEMISTRY LA English DT Article AB Two pure solvents (trichloroethene and dichloromethane) were evaporated at room temperature (24 +/- 1 degrees C). The carbon and chlorine isotopic compositions of the residual solvents were measured as a function of the fraction remaining. Isotopic fractionation factors (alpha) derived From these experimental results are 1.00031 +/- 0.00004 for C and 0.99818 +/- 0.00022 for Cl in trichloroethene, and 1.00065 +/- 0.00002 for C and 0.99952 +/- 0.00006 for Cl in dichloromethane. The negative correlation between delta(13)C and delta(37)Cl values caused by evaporation of chlorinated aliphatic hydrocarbons can be used to distinguish evaporation from biodegradation in contaminated systems. (C) 1999 Published by Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. RP Huang, L (reprint author), Environm Canada, Atomospher Environm Serv, Toronto, ON M3H 5T4, Canada. NR 26 TC 112 Z9 122 U1 0 U2 19 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0146-6380 J9 ORG GEOCHEM JI Org. Geochem. PY 1999 VL 30 IS 8A BP 777 EP 785 DI 10.1016/S0146-6380(99)00060-1 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 238NC UT WOS:000082715500006 ER PT J AU Heraty, LJ Fuller, ME Huang, L Abrajano, T Sturchio, NC AF Heraty, LJ Fuller, ME Huang, L Abrajano, T Sturchio, NC TI Isotopic fractionation of carbon and chlorine by microbial degradation of dichloromethane SO ORGANIC GEOCHEMISTRY LA English DT Article ID INSITU BIODEGRADATION; AQUIFER; METHANE; HYDROCARBONS; OXIDATION; DIOXIDE; RATIOS; SOIL AB Microbial culture experiments were performed at 22 degrees C to investigate isotopic fractionation of carbon (C) and chlorine (Cl) during aerobic degradation of dichloromethane (DCM) by MC8b, a gram-negative methylotrophic organism closely related to the genera Methylobacterium or Ochrobactrum. Values of the isotopic fractionation factor, alpha, were estimated from the experimental results. These values are 0.9576 +/- 0.0015 for C and 0.9962 +/- 0.0003 for Cl, corresponding to kinetic isotope effects (KIE) of 1.0424 for C and 1.0038 for Cl. The C isotope effect accompanying aerobic degradation of DCM by MC8b is roughly twice that resulting from microbial oxidation of CH4. Further studies of this type, for a variety of chlorinated aliphatic hydrocarbons (CAHs) under a range of biogeochemical conditions, may find important applications in the characterization and remediation of sites contaminated with CAHs. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. RP Heraty, LJ (reprint author), Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. NR 25 TC 69 Z9 75 U1 3 U2 18 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0146-6380 J9 ORG GEOCHEM JI Org. Geochem. PY 1999 VL 30 IS 8A BP 793 EP 799 DI 10.1016/S0146-6380(99)00062-5 PG 7 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 238NC UT WOS:000082715500008 ER PT J AU Conrad, ME Tempeton, AS Daley, PF Alvarez-Cohen, L AF Conrad, ME Tempeton, AS Daley, PF Alvarez-Cohen, L TI Isotopic evidence for biological controls on migration of petroleum hydrocarbons SO ORGANIC GEOCHEMISTRY LA English DT Article DE intrinsic bioremediation; petroleum hydrocarbons; methanogenesis; carbon isotopes; radiocarbon ID STABLE CARBON ISOTOPES; METHANE; BIODEGRADATION; FRACTIONATION; SOIL; OXIDATION; ACETATE; METABOLISM; MARINE; ZONE AB The isotopic compositions of potential metabolic byproducts of petroleum hydrocarbon biodegradation in soil gas and groundwater samples from a shallow plume of aviation gas (AVGAS) were analyzed to assess levels and pathways of intrinsic bioremediation occurring at the site. Gasoline range organic compounds (GROs) in soil gas samples from the original source area were low (<1000 ppm), but GRO levels under an adjacent, asphalt-covered parking lot exceeded 100,000 ppm. Soil gas CH4 was > 20% in the central part of the plume and correlated well with GRO concentrations. The C-14 contents of the CH4, associated soil gas CO2 and dissolved inorganic carbon compounds (DIC) in the groundwater were all less than 0.1 times modern, indicating they were primarily formed from degradation of AVGAS and not other potential carbon sources such as degradation of natural organic matter or dissolution of carbonate shells. The delta D and delta(13)C values of the CH4 indicate that it was produced via acetate fermentation. The delta(13)C values of CO2 and DIC in the central part of the plume were high, suggesting that a large fraction of the CO2 in that area was also produced by acetate fermentation. At the down-gradient edges of the plume, CH4 levels dropped to zero and the delta(13)C values of CO2 were much lower (-26 parts per thousand), indicating that aerobic degradation of the AVGAS was dominant in this area. Beyond the down-gradient edges of the plume, the C-14 contents of both groundwater DIC and soil gas CO2 were significantly below modern levels, implying that most of the carbon there was derived from hydrocarbons and had migrated beyond the edge of the plume. These data show that methanogenic activity in the central part of the plume was slowly degrading the AVGAS, but aerobic activity at the edges of the plume was effectively limiting migration of the hydrocarbons. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Ctr Isotope Geochem, EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Environm Restorat Div, Livermore, CA 94550 USA. Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. RP Conrad, ME (reprint author), Ctr Isotope Geochem, EO Lawrence Berkeley Natl Lab, Mailstop 70A-3363, Berkeley, CA 94720 USA. RI Conrad, Mark/G-2767-2010; OI TEMPLETON, ALEXIS/0000-0002-9670-0647 NR 31 TC 16 Z9 16 U1 0 U2 13 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0146-6380 J9 ORG GEOCHEM JI Org. Geochem. PY 1999 VL 30 IS 8A BP 843 EP 859 DI 10.1016/S0146-6380(99)00067-4 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 238NC UT WOS:000082715500013 ER PT S AU Shaltout, RM Loy, DA Wheeler, DR AF Shaltout, RM Loy, DA Wheeler, DR BE Klein, LC Francis, LF DeGuire, MR Mark, JE TI Maleimide functionalized siloxane resins SO ORGANIC/INORGANIC HYBRID MATERIALS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium DD on Organic Inorganic Hybrid Materials held at the 1999 MRS Spring Meeting CY APR 05-09, 1999 CL SAN FRANCISCO, CA SP 3M, Ctr Adv Mat Technol, Chemat Technol Inc, Eastman Kodak Co AB In-situ filling through hydrolysis and condensation of silicon alkoxides dissolved into polymers has been utilized to generate nanocomposites in which the filler phase can be intimately associated with the polymer on relatively small length scales. One problem of the method has been achieving useful fill volumes without bulk phase separation of the growing inorganic component from the polymer. Zn this paper, we describe the preparation of a new class of nanocomposite materials in which the inorganic filler phase is pre-assembled before copolymerization with an organic monomer. Maleimide monomers, prepared from alkoxysilylpropyl amines and maleic anhydride, were protected against side reactions by forming the oxonorbornene Diels-Alder adduct with furan. The monomers were then reacted under sol-gel conditions to form oligomers or polymers making up the filler phase. The material was activated by thermal deprotection of the maleimide and reacted with organic monomers or polymers to form the filled nanocomposite. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Shaltout, RM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Loy, Douglas/D-4847-2009 OI Loy, Douglas/0000-0001-7635-9958 NR 4 TC 4 Z9 4 U1 2 U2 6 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-483-1 J9 MATER RES SOC SYMP P PY 1999 VL 576 BP 15 EP 20 PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Materials Science, Composites; Physics, Applied SC Chemistry; Materials Science; Physics GA BP22B UT WOS:000084438000002 ER PT S AU Rahimian, K Loy, DA AF Rahimian, K Loy, DA BE Klein, LC Francis, LF DeGuire, MR Mark, JE TI Sol-gel chemistry by ring-opening polymerization SO ORGANIC/INORGANIC HYBRID MATERIALS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium DD on Organic Inorganic Hybrid Materials held at the 1999 MRS Spring Meeting CY APR 05-09, 1999 CL SAN FRANCISCO, CA SP 3M, Ctr Adv Mat Technol, Chemat Technol Inc, Eastman Kodak Co AB Sol-gel processing of materials is plagued by shrinkage during polymerization of the alkoxide monomers and processing (aging and drying) of the resulting gels. We have developed a new class of hybrid organic-inorganic materials based on the solventless ring-opening polymerization (ROP) of monomers bearing the 2,2,5,5-tetramethyl-2,5-disilaoxacyclopentyl group, which permits us to drastically reduce shrinkage in sol-gel processed materials. Because the monomers are polymerized through a chain growth mechanism catalyzed by base rather than the step growth mechanism normally used in sol-gel systems, hydrolysis and condensation products are entirely eliminated. Furthermore, since water is not required for hydrolysis, an alcohol solvent is not necessary. Monomers with two disilaoxacyclopentyl groups, separated by a rigid phenylene group or a more flexible alkylene group, were prepared through disilylation of the corresponding diacetylenes, followed by ring closure and hydrogenation. Anionic polymerization of these materials, either neat or with 2,2,5,5-tetramethyl-2,5-disila-1-oxacyclopentane as a copolymer, affords thermally stable transparent gels with no visible shrinkage. These materials provide an easy route to the introduction of sol-gel type materials in encapsulation of microelectronics, which we have successfully demonstrated. C1 Sandia Natl Labs, Catalysts Dept, Albuquerque, NM 87185 USA. RP Rahimian, K (reprint author), Sandia Natl Labs, Catalysts Dept, POB 5800, Albuquerque, NM 87185 USA. RI Loy, Douglas/D-4847-2009 OI Loy, Douglas/0000-0001-7635-9958 NR 7 TC 1 Z9 1 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-483-1 J9 MATER RES SOC SYMP P PY 1999 VL 576 BP 63 EP 67 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Materials Science, Composites; Physics, Applied SC Chemistry; Materials Science; Physics GA BP22B UT WOS:000084438000009 ER PT S AU Assink, RA Click, CA Alam, TM Brinker, CJ Naik, SJ AF Assink, RA Click, CA Alam, TM Brinker, CJ Naik, SJ BE Klein, LC Francis, LF DeGuire, MR Mark, JE TI A silicon, carbon and deuterium NMR investigation of molecular templating in amorphous silicas SO ORGANIC/INORGANIC HYBRID MATERIALS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium DD on Organic Inorganic Hybrid Materials held at the 1999 MRS Spring Meeting CY APR 05-09, 1999 CL SAN FRANCISCO, CA SP 3M, Ctr Adv Mat Technol, Chemat Technol Inc, Eastman Kodak Co ID MEMBRANES AB The precise pore sizes defined by crystalline zeolite lattices have led to intensive research on zeolite membranes. Unfortunately zeolites have proven to be extremely difficult to prepare in a defect-free thin film form needed for membrane flux and selectivity We introduce tetrapropylammonium TPA (a structure directing agent for zeolite ZSM-5) into a silica sol and exploit the development of high solvation stresses to create templated amorphous silicas with pore apertures comparable in size to those of ZSM-5. Si-29 and H-2 NMR experiments were performed to evaluate the efficacy of our templating approach. The Si-29 NMR spectrum of the silica matrix was observed by an intermolecular cross-polarization experiment between the H-1 nuclei of TPA and the Si-29 nuclei in the silica matrix. The efficiency of the cross-polarization interaction was used to investigate the degree to which the matrix formed a tight cage surrounding the template molecule. Bulk xerogels, prepared by gelation and slow drying of the corresponding sols, exhibited only weak interactions between the two sets of nuclei. Thin film xeorgels, where drying stresses are greater, resulted in significantly increased interactions. Analogous materials were prepared using fully deuterated TPA. The H-2 NMR wideline spectra consisted of a partially narrowed resonance, corresponding to template molecules which were undergoing restricted rotational motion, and an isotropically narrowed resonance, corresponding to molecules which were undergoing rapid rotational motion. The number of isotropically rotating template molecules decreased for the thin film specimens, consistent with improved templating of amorphous silica by TPA. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Assink, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 1 Z9 1 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-483-1 J9 MATER RES SOC SYMP P PY 1999 VL 576 BP 83 EP 88 PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Materials Science, Composites; Physics, Applied SC Chemistry; Materials Science; Physics GA BP22B UT WOS:000084438000012 ER PT S AU Loy, DA Beach, JV Baugher, BM Assink, RA Shea, KJ Tran, J Small, JH AF Loy, DA Beach, JV Baugher, BM Assink, RA Shea, KJ Tran, J Small, JH BE Klein, LC Francis, LF DeGuire, MR Mark, JE TI Dialkylenecarbonate-bridged polysilsesquioxanes. Hybrid organic-inorganic sol-gels with a thermally labile bridging group SO ORGANIC/INORGANIC HYBRID MATERIALS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium DD on Organic Inorganic Hybrid Materials held at the 1999 MRS Spring Meeting CY APR 05-09, 1999 CL SAN FRANCISCO, CA SP 3M, Ctr Adv Mat Technol, Chemat Technol Inc, Eastman Kodak Co AB In this paper, we introduce a new approach for altering the properties of bridged polysilsesquioxane xerogels using post-processing modification of the polymeric network. The bridging organic group contains latent functionalities that can be liberated thermally, photochemically, or by chemical means after the gel has been processed to a xerogel. These modifications can produce changes in density, solubility, porosity, and or chemical properties of the material. Since every monomer possesses two latent functional groups, the technique allows for the introduction of high levels of functionality in hybrid organic-inorganic materials. Dialkylenecarbonate-bridged polysilsesquioxane gels were prepared by the sol-gel polymerization of bis(triethoxysilylpropyl)carbonate (1) and bis(triethoxysilylisobutyl)carbonate (2). Thermal treatment of the resulting non-porous xerogels and aerogels at 300-350 degrees C resulted in quantitative decarboxylation of the dialkylenecarbonate bridging groups to give new hydroxyalkyl and olefinic substituted polysilsesquioxane monolithic xerogels and aerogels that can not be directly prepared through direct sol-gel polymerization of organotrialkoxysilanes. C1 Sandia Natl Labs, Catalysts Dept, Albuquerque, NM 87185 USA. RP Loy, DA (reprint author), Sandia Natl Labs, Catalysts Dept, POB 5800, Albuquerque, NM 87185 USA. RI Loy, Douglas/D-4847-2009 OI Loy, Douglas/0000-0001-7635-9958 NR 10 TC 4 Z9 4 U1 0 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-483-1 J9 MATER RES SOC SYMP P PY 1999 VL 576 BP 99 EP 104 PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Materials Science, Composites; Physics, Applied SC Chemistry; Materials Science; Physics GA BP22B UT WOS:000084438000015 ER PT S AU Baugher, BM Schneider, DA Loy, DA Rahimian, K AF Baugher, BM Schneider, DA Loy, DA Rahimian, K BE Klein, LC Francis, LF DeGuire, MR Mark, JE TI Porosity in polysilsesquioxane xerogels SO ORGANIC/INORGANIC HYBRID MATERIALS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium DD on Organic Inorganic Hybrid Materials held at the 1999 MRS Spring Meeting CY APR 05-09, 1999 CL SAN FRANCISCO, CA SP 3M, Ctr Adv Mat Technol, Chemat Technol Inc, Eastman Kodak Co AB Polymerization of organotrialkoxysilanes is a convenient method for introducing organic functionality into hybrid organic-inorganic materials. However, not much is known about the effects of the organic substituent on the porosity of the resulting xerogels. In this study, we prepared a series of polysilsesquioxane xerogels from organotrialkoxysilanes, RSi(OR')(3), with different organic groups (R = H, Me, Et, dodecyl, hexadecyl, octadecyl, vinyl, chloromethyl, cyanoethyl). Polymerizations of the monomers were carried out under a variety of conditions, varying monomer concentration, type of catalyst, and alkoxide substituent. The effect of the organic substituent on the sol-gel process was often dramatic. In many cases, gels were formed only at very high monomer concentration and/or with only one type of catalyst. All of the gels were processed as xerogels and characterized by scanning electron microscopy and nitrogen sorption porosimetry to evaluate their pore structure. C1 Sandia Natl Labs, Catalysts Dept, Albuquerque, NM 87185 USA. RP Baugher, BM (reprint author), Sandia Natl Labs, Catalysts Dept, POB 5800, Albuquerque, NM 87185 USA. RI Loy, Douglas/D-4847-2009 OI Loy, Douglas/0000-0001-7635-9958 NR 10 TC 2 Z9 2 U1 0 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-483-1 J9 MATER RES SOC SYMP P PY 1999 VL 576 BP 105 EP 110 PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Materials Science, Composites; Physics, Applied SC Chemistry; Materials Science; Physics GA BP22B UT WOS:000084438000016 ER PT S AU McBranch, DW Kraabel, B Xu, S Wang, HL Klimov, VI AF McBranch, DW Kraabel, B Xu, S Wang, HL Klimov, VI BE Kafafi, ZH TI Universal ultrafast signatures of photoexcitations in conjugated polymers: excitons and charge-transfer polarons SO ORGANIC LIGHT-EMITTING MATERIALS AND DEVICES III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Organic Light-Emitting Materials and Devices III CY JUL 19-21, 1999 CL DENVER, CO SP SPIE DE femtosecond transient absorption; excitons; polarons; conjugated polymers ID PHOTOINDUCED ABSORPTION; TRANSIENT-ABSORPTION; STIMULATED-EMISSION; POLY(P-PHENYLENEVINYLENE); SPECTROSCOPY; GENERATION; RELAXATION; OLIGOMERS; DYNAMICS; STATES AB Using subpicosecond transient absorption spectroscopy, we have investigated the primary photoexcitations in thin films and solutions of several phenylene-based conjugated polymers and an oligomer. We identify two features in the transient absorption spectra and dynamics that are common to all of the materials which we have studied from this family. The first spectral feature is a photoinduced absorption (PA) band peaking near 1 eV which has intensity-dependent dynamics which match the stimulated emission dynamics exactly over two orders of magnitude in excitation density. This band is associated with singlet intrachain excitons. The second spectral feature (observed only in thin films and aggregated solutions) is a PA band peaking near 1.8 eV, which is longer-lived than the 1 eV exciton PA band, and which has dynamics that are independent (or weakly-dependent) on excitation density. This feature is attributed to charge separated (interchain) excitations. These excitations are generated through a bimolecular process. By comparing to samples in which charged excitations are created deliberately by doping with C(6)0, we assign these secondary species as bound polarons. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP McBranch, DW (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, POB 1663, Los Alamos, NM 87545 USA. NR 30 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 0-8194-3283-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3797 BP 17 EP 25 DI 10.1117/12.372706 PG 9 WC Materials Science, Multidisciplinary; Optics; Physics, Applied; Physics, Condensed Matter; Polymer Science SC Materials Science; Optics; Physics; Polymer Science GA BP45Y UT WOS:000085205700002 ER PT S AU Shinar, J Uhlhorn, BL Partee, J Kim, CH Lee, MK List, EJW Graupner, W Leising, G AF Shinar, J Uhlhorn, BL Partee, J Kim, CH Lee, MK List, EJW Graupner, W Leising, G BE Kafafi, ZH TI Frequency-resolved delayed fluorescence (DF) and photoluminescence detected magnetic resonance (PLDMR) studies of triplet and polaron dynamics in pi-conjugated materials & devices SO ORGANIC LIGHT-EMITTING MATERIALS AND DEVICES III SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Organic Light-Emitting Materials and Devices III CY JUL 19-21, 1999 CL DENVER, CO SP SPIE DE conjugated polymers; delayed fluorescence; photoluminescence (PL); PL-detected magnetic resonance (PLDMR); intermolecular coupling ID LIGHT-EMITTING-DIODES; LONG-LIVED POLARONS; PHOTOEXCITED STATES; POLY(PARA-PHENYLENE VINYLENE); POLYMERS; POLY(PARAPHENYLENEVINYLENE); SPECTROSCOPY; EXCITONS; PAIRS; FILMS AB The DF and PLDMR of triplet exciton and polaron dynamics in li-conjugated materials and devices is reviewed, and the significance of various processes involving these long-lived excitations is considered. These include the generation of singlet excitons by triplet-triplet annihilation, which leads to DF, and nonradiative quenching of such singlets by polarons or triplet excitons. The clear differences between the roles of these processes in pi-conjugated polymers vs small molecules and their implications for organic light emitting devices are discussed. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. Graz Univ Technol, Inst Festkorperphys, A-8010 Graz, Austria. Virginia Tech, Dept Phys, Blacksburg, VA 24061 USA. RP Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. RI List-Kratochvil, Emil/M-5312-2013 NR 33 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 0-8194-3283-0 J9 PROC SPIE PY 1999 VL 3797 BP 76 EP 88 DI 10.1117/12.372699 PG 13 WC Materials Science, Multidisciplinary; Optics; Physics, Applied; Physics, Condensed Matter; Polymer Science SC Materials Science; Optics; Physics; Polymer Science GA BP45Y UT WOS:000085205700008 ER PT S AU Yakimov, AV Savvate'ev, VN Davidov, D Pfeiffer, S Horhold, HH AF Yakimov, AV Savvate'ev, VN Davidov, D Pfeiffer, S Horhold, HH BE Kafafi, ZH TI Transient electroluminescence from polymer-based LED devices SO ORGANIC LIGHT-EMITTING MATERIALS AND DEVICES III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Organic Light-Emitting Materials and Devices III CY JUL 19-21, 1999 CL DENVER, CO SP SPIE DE transient electroluminescence; light emitting diodes; conjugated polymers ID LIGHT-EMITTING-DIODES AB We report on the observation of switching or "off-phase" electroluminescence (EL) spikes in thick devices (300 nm to 600 nm) based on poly-2-methoxy,5-(2'-ethylhexoxy)-1,4-phenylenevinylene (MEH-PPV) conjugated polymer sandwiched between Aluminum and Indium-Tin-Oxide (ITO) electrodes. We also report on impedance spectroscopy studies on the same samples. Transient EL measurements were carried out using voltage pulses with pulse width in the range between several microseconds and 10 nanoseconds and voltage pulse height up to 1000 V. The short pulses are obtained using a home-built voltage pulse source consisting of inorganic photo-switch governed by light pulses from Nd:YaG laser. The electrical pulse rise-time is determined by the laser pulse rise-time, which is around 3 nanoseconds. The off-phase Fl, is manifested by the appearance of two EL spikes at the turn-on and the turn-off edges of the voltage pulse; for very short voltage pulses the two spikes merge. We demonstrate that the EL emission spectrum associated with the off-phase Fl, is similar, although not identical, to the regular injection EL spectrum of MEH-PPV, suggesting that the off-phase EL is also due to singlet exciton recombination. We show, for the first time, transient EL as a function of the pulse height up to 200 V using pulse width as narrow as 15 nanoseconds. For such strong and short pulses the Fl, emission is dominated by the off-phase EL mechanism. We provide evidence from impedance spectroscopy that one of the relaxation processes has a characteristic time of the order of magnitude of the time scales observed in the off-phase EL. This may shed light on the relaxation processes in the switching EL. C1 Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. Iowa State Univ, US DOE, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. Univ Jena, Inst Organ Chem & Makromol Chem, D-07743 Jena, Germany. RP Yakimov, AV (reprint author), Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. NR 10 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 0-8194-3283-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3797 BP 237 EP 245 DI 10.1117/12.372715 PG 9 WC Materials Science, Multidisciplinary; Optics; Physics, Applied; Physics, Condensed Matter; Polymer Science SC Materials Science; Optics; Physics; Polymer Science GA BP45Y UT WOS:000085205700023 ER PT S AU Kraabel, B Mikhailovsky, A Wang, HL McBranch, DW AF Kraabel, B Mikhailovsky, A Wang, HL McBranch, DW BE Eich, M Kuzyk, MG TI Molecular control of charge and energy transfer in self-assembled polymer films: towards improved ultrafast holographic materials SO ORGANIC NONLINEAR OPTICAL MATERIALS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Organic Nonlinear Optical Materials CY JUL 19-22, 1999 CL DENVER, CO SP SPIE DE femtosecond holography; self-assembly; conjugated polymers; energy transfer AB We report on the optical characterization of a series of multi-layered organic superlattices made by polyelectrolyte self-assembly. Using a high molecular weight, water-soluble, anionic form of poly-phenylene vinylene, self-assembled films can be formed which show high photoluminescence quantum efficiency (QE). A dramatic red shift of the luminescence (up to 75 nm) and increase in QE is observed as additional PPV layers are added. We attribute the red shift and increasing QE to a changing conformation of the polymer chains as the superstructure is assembled, together with efficient Frster energy transfer in a preferred direction away from the substrate toward layers with longer effective conjugation length. Upon adding a C-60 top layer, the luminescence spectrum is strongly quenched. We attribute to this to charge transfer of from the top-most polymer layer to the C-60 layer. We discuss the possibilities of exploiting this directional charge transfer in an ultrafast holographic device along with other options for increasing the temporal diffraction efficiency of polymer-based mediums. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Kraabel, B (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. NR 9 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 0-8194-3282-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3796 BP 43 EP 48 DI 10.1117/12.368299 PG 6 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BN98E UT WOS:000083742500006 ER PT S AU Casson, JL Huang, WX Lee, YW Bardeau, JF Johal, MS Rong, W Li, DQ Swanson, BI McBranch, DW Helvenston, M Robinson, JM AF Casson, JL Huang, WX Lee, YW Bardeau, JF Johal, MS Rong, W Li, DQ Swanson, BI McBranch, DW Helvenston, M Robinson, JM BE Eich, M Kuzyk, MG TI NLO-studies of a novel phenothiazine self-assembled monolayer SO ORGANIC NONLINEAR OPTICAL MATERIALS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Organic Nonlinear Optical Materials CY JUL 19-22, 1999 CL DENVER, CO SP SPIE DE second harmonic generation; non linear optics; thin films; monolayers; FTIR; spectroscopy; chromophore ID ION-EXCHANGE PROCESSES; 2ND-HARMONIC GENERATION; MOLECULAR-ORIENTATION; THIN-FILMS; SURFACES AB The nonlinear optical behavior of self-assembled monolayer films of a new NLO-active molecule, 4-(trans-4-(4-(10-phenothiazinyl)butyramido)styryl)pyridine (PBSP), is characterized by second harmonic generation (SHG). PBSP contains a heterocyclic sulfonate head group and a highly polarizable chromophore. The films are synthesized by a nucleophilic substitution reaction on both sides of a quartz substrate that has been treated with a coupling layer (p-(chloromethyl)phenyl trichlorosilane). The addition of the chromophoric layer is monitored by AFM, FTIR and UV-visible spectroscopy, and SHG. The FTIR spectrum of the first layer shows weak methylene resonances, while the spectrum with the addition of the second layer shows much stronger methylene resonances and an amine resonance. The characterization of the film by SHG was done by rotating the film and generating Maker fringes. The polarization dependence of the SHG signal was also determined. The SHG signal after the nucleophilic reaction was an order of magnitude greater than before the reaction. The magnitude of the dominant element of the nonlinear susceptibility and the average molecular orientation angle of the chromophore were determined by modeling the Maker fringes and the polarization dependence of the SHG signal. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Casson, JL (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. NR 35 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 0-8194-3282-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3796 BP 238 EP 246 DI 10.1117/12.368280 PG 9 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BN98E UT WOS:000083742500026 ER PT S AU Partee, J Frankevich, EL Uhlhorn, B Shinar, J Ding, Y Barton, TJ AF Partee, J Frankevich, EL Uhlhorn, B Shinar, J Ding, Y Barton, TJ BE Kippelen, B Lackritz, HS Claus, RO TI Frequency resolved photoluminescence (PL), delayed fluorescence and triplet-triplet annihilation in pi-conjugated polymers SO ORGANIC NONLINEAR OPTICAL MATERIALS AND DEVICES SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium F on Organic Nonlinear Optical Materials and Devices, at the 1999 MRS Spring Meeting CY APR 06-09, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc ID DETECTED MAGNETIC-RESONANCE; PHOTOEXCITED STATES; POLY(PARA-PHENYLENE VINYLENE); OPTICAL SPECTROSCOPY; EXCITON DYNAMICS; POLARON PAIRS; POLY(PARAPHENYLENEVINYLENE) AB The delayed fluorescence of poly(p-phenylene vinylene) (PPV) and poly(p-phenylene ethynylene) (PPE) derivative solids and frozen solutions at 20 K is described. It provides strong evidence for triplet-triplet annihilation to singlets excitons accounting for up to similar to 3% of the total emission in PPV films and similar to 1.5% in PPE powder. It also yields triplet lifetimes of 70 and 110 mu s in PPV films and frozen solutions, and similar to 200 and similar to 500 mu s in PPE powder and frozen solutions, respectively. C1 US DOE, Ames Lab, Ames, IA 50011 USA. RP US DOE, Ames Lab, Ames, IA 50011 USA. NR 28 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOC PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-468-8 J9 MATER RES SOC SYMP P PY 1999 VL 561 BP 215 EP 220 PG 6 WC Materials Science, Multidisciplinary; Optics; Polymer Science SC Materials Science; Optics; Polymer Science GA BN69D UT WOS:000082590800034 ER PT J AU Economos, CD Nelson, ME Singh, MAF Kehayias, JJ Dallal, GE Heymsfield, SB Wang, J Yasumura, S Ma, R Pierson, RN AF Economos, CD Nelson, ME Singh, MAF Kehayias, JJ Dallal, GE Heymsfield, SB Wang, J Yasumura, S Ma, R Pierson, RN TI Bone mineral measurements: A comparison of delayed gamma neutron activation, dual-energy X-ray absorptiometry and direct chemical analysis SO OSTEOPOROSIS INTERNATIONAL LA English DT Article DE accuracy; bone mineral; calcium; DXA; neutron activation ID LEAN BODY-MASS; SOFT-TISSUE MEASUREMENTS; PHOTON-ABSORPTIOMETRY; LUMBAR SPINE; WHOLE-BODY; IN-VIVO; UNIVERSAL STANDARDIZATION; DENSITY MEASUREMENTS; ACCURACY; CALIBRATION AB A system in vitro consisting of a femur from a cadaver and soft-tissue equivalent material was used to test the agreement between several techniques for measuring bone mineral. Calcium values measured by delayed gamma neutron activation (DGNA) and bone mineral content (BMC) by Lunar, Hologic and Norland dual-energy X-ray absorptiometers (DXA) were compared with calcium and ash content determined by direct chemical analysis. To assess the effect of soft-tissue thickness on measurements of bone mineral, we had three phantom configurations ranging from 15.0 to 26.0 cm in thickness. achieved by using soft-tissue equivalent overlays. Chemical analysis of the femur gave calcium and ash content values of 61.83 g +/- 0.51 g and 154.120 +/- 0.004 g, respectively. Calcium measured by DGNA did not differ from the ashed amount of calcium at any of the phantom configurations. The BMC measured by DXA was significantly higher, by 3-5%, than the amount determined by chemical analysis for the Lunar densitometer and significantly lower, by 3-6%, for the Norland densitometer (p<0.001-0.024). but only 1% lower (not significant) for the Hologic densitometer. DXA instruments showed a decreasing trend in BMC as the thickness increased from 20.5 to 26.0 cm (p<0.05). However. within the entire thickness range (15.0-26.0 cm). the overall influence of thickness on BMC by DXA was very small. These findings offer insight into the differences in these currently available methods for bone mineral measurement and challenge the comparability of different methods. C1 Tufts Univ, USDA, Human Nutr Res Ctr Aging, Exercise Physiol & Sarcopenia Lab, Boston, MA 02111 USA. St Lukes Roosevelt Hosp, New York, NY 10025 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Economos, CD (reprint author), Tufts Univ, USDA, Human Nutr Res Ctr Aging, Exercise Physiol & Sarcopenia Lab, 711 Washington St, Boston, MA 02111 USA. FU NIA NIH HHS [T32 AG00209]; NIDDK NIH HHS [P01-DK42618] NR 66 TC 9 Z9 9 U1 0 U2 2 PU SPRINGER-VERLAG LONDON LTD PI GODALMING PA SWEETAPPLE HOUSE CATTESHALL ROAD, GODALMING GU7 3DJ, SURREY, ENGLAND SN 0937-941X J9 OSTEOPOROSIS INT JI Osteoporosis Int. PY 1999 VL 10 IS 3 BP 200 EP 206 DI 10.1007/s001980050216 PG 7 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 244UU UT WOS:000083069800004 PM 10525711 ER PT J AU Aloia, JF Ma, R Vaswani, A Feuerman, M AF Aloia, JF Ma, R Vaswani, A Feuerman, M TI Total-body calcium estimated by delayed gamma neutron activation analysis and dual-energy X-ray absorptiometry SO OSTEOPOROSIS INTERNATIONAL LA English DT Article DE bone mineral; dual-energy X-ray absorptiometry; neutron activation analysis; total body calcium ID BONE-MINERAL CONTENT; PHOTON-ABSORPTIOMETRY; BLACK-WOMEN; ACCURACY; CALIBRATION; INVIVO; PRECISION; LUNAR; PHANTOM; DESIGN AB Total body calcium (TBCa) in 270 black and white women age 21-79 years was measured concurrently by delayed gamma neutron activation analysis (DGNA) and dual-energy X-ray absorptiometry (DXA). The mean value for TBCa calculated from DXA was 933 g compared with 730 g for DGNA, By regression, TBCa(DXA(g)) = 1.35 x TBCa(DGNA(g)) - 54 (r = 0.90, r(2) = 81.4%, SEE = 66.9 g). This remarkable difference of 203 g suggests that one or both these methods is not accurate. Adjustment of the regression of DXA versus DGNA for body mass index or trunk thickness explained 8.5-10% of the variability between methods. The unadjusted slope for the DXA values regressed against the DGNA values was 1.35, indicating significant discordance between the methods. There is greater agreement between the two DGNA facilities (Brookhaven National Laboratory and Baylor College of Medicine) and between the various DXA instruments. Either DGNA underestimates TBCa or DXA overestimates total-body bone mineral content. Resolution of these disparate results may possibly be achieved by concurrent measurement of whole human cadavers of different sizes with chemical determination of the calcium content of the ash. In the interim, cross-calibration equations between DGNA and standardized values for DXA for total-body bone mineral content may be used, which will permit reporting of consistent values for TBCa from the two technologies. C1 Winthrop Univ Hosp, Dept Med, Mineola, NY 11501 USA. Brookhaven Natl Lab, New York, NY USA. RP Aloia, JF (reprint author), Winthrop Univ Hosp, Dept Med, 259 1st St, Mineola, NY 11501 USA. NR 39 TC 2 Z9 2 U1 0 U2 1 PU SPRINGER LONDON LTD PI LONDON PA 236 GRAYS INN RD, 6TH FLOOR, LONDON WC1X 8HL, ENGLAND SN 0937-941X J9 OSTEOPOROSIS INT JI Osteoporosis Int. PY 1999 VL 10 IS 6 BP 510 EP 515 DI 10.1007/s001980050262 PG 6 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 276EP UT WOS:000084862900012 PM 10663353 ER PT J AU Luo, G Kinney, JH Kaufman, JJ Haupt, D Chiabrera, A Siffert, RS AF Luo, G Kinney, JH Kaufman, JJ Haupt, D Chiabrera, A Siffert, RS TI Relationship between plain radiographic patterns and three-dimensional trabecular architecture in the human calcaneus SO OSTEOPOROSIS INTERNATIONAL LA English DT Article DE Micro-CT; osteoporosis; plain radiograph; three-dimensional; trabecular bone; trabecular architecture ID IN-VIVO; QUANTITATIVE-ANALYSIS; BONE BIOPSIES; ORGANIZATION; OSTEOPOROSIS; MICROSCOPY AB The purpose of this study was to determine the relationship between three-dimensional (3D) trabecular structure and two-dimensional plain radiographic patterns. An in vitro cylinder of human calcaneal trabecular bone was three-dimensionally imaged by micro-CT using synchrotron radiation, at 33.4 mu m resolution. The original 3D image was processed using 14 distinct sequences of morphologic operations, i.e., of dilations and erosions, to obtain a total of 15 3D models or images of calcaneal trabecular bone. These 15 models had distinct densities (volume fractions) and architectures. The 3D structure of each calcaneal model was assessed using mean intercept length (fabric), by averaging individual fabric measurements associated with each medial-lateral image slice, and determining the relative anisotropy, R-3D, Of the structure. A summated pattern or plain radiograph was also computed from the 3D image data for each calcaneal model. Each summated pattern was then locally thresholded, and the resulting two-dimensional (2D) binary image analyzed using the same fabric analysis as used for the 3D data. The anisotropy of the 2D summated pattern was denoted by Rx-ray. The volume fractions of the 15 models ranged from 0.08 to 0.19 with a mean of 0.14. The medial-lateral anisotropies, R-3D, ranged from 1.38 to 2.54 with a mean of 1.88. The anisotropy of the 2D summated patterns, Rx-ray, ranged from 1.35 to 2.18 with a mean of 1.71. The linear correlation of the 3D trabecular architecture, R-3D, With the radiographic trabecular architecture, Rx-ray, was 0.99 (p<0.0001). This study shows that the plain radiograph contains architectural information directly related to the underlying 3D structure. A well-controlled sequential reproducible plain radiograph may prove useful for monitoring changes in trabecular architecture in vivo and in identifying those individuals at increased risk of osteoporotic fracture. C1 Mt Sinai Sch Med, Dept Orthopaed, New York, NY 10029 USA. NYU Med Ctr, Dept Rehabil Med, New York, NY 10016 USA. Dept Vet Affairs Med Ctr, New York, NY USA. Univ Calif Lawrence Livermore Natl Lab, Dept Mat Sci, Livermore, CA USA. Univ Genoa, DIBE, I-16145 Genoa, Italy. RP Siffert, RS (reprint author), Mt Sinai Sch Med, Dept Orthopaed, 1 Gustave L Levy Pl,Box 1188, New York, NY 10029 USA. FU NIDDK NIH HHS [5T35DK07420] NR 25 TC 54 Z9 56 U1 0 U2 3 PU SPRINGER-VERLAG LONDON LTD PI GODALMING PA SWEETAPPLE HOUSE CATTESHALL ROAD, GODALMING GU7 3DJ, SURREY, ENGLAND SN 0937-941X J9 OSTEOPOROSIS INT JI Osteoporosis Int. PY 1999 VL 9 IS 4 BP 339 EP 345 DI 10.1007/s001980050156 PG 7 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 200DE UT WOS:000080523700009 PM 10550451 ER PT B AU VanDevender, JP Barker, JR AF VanDevender, JP Barker, JR BE Hunt, JG Dodge, GE Wong, L TI Leadership and decision processing in twenty-first-century technical organizations SO OUT-OF-THE-BOX LEADERSHIP: TRANSFORMING THE TWENTY-FIRST-CENTURY ARMY AND OTHER TOP-PERFORMING ORGANIZATIONS SE MONOGRAPHS IN LEADERSHIP AND MANAGEMENT LA English DT Proceedings Paper CT Conference on Out of the Box Leadership - Transforming the 21st Century Army and Other Top Performing Organizations CY MAR 27-28, 1996 CL 1ST INFANTRY DIV, WHEATON, IL SP Army Res Inst Behavioral & Social Sci HO 1ST INFANTRY DIV C1 Sandia Natl Labs, Livermore, CA 94550 USA. RI Barker, James/A-1448-2008 NR 8 TC 0 Z9 0 U1 0 U2 0 PU JAI PRESS INC PI STAMFORD PA 100 PROSPECT STREET, STAMFORD, CT 06901-1640 USA BN 0-7623-0548-7 J9 MONOGR LEAD MANAGE PY 1999 VL 1 BP 91 EP 107 PG 17 WC Management SC Business & Economics GA BM78M UT WOS:000079757000007 ER PT B AU Isgur, N AF Isgur, N BE Frois, B Bouchiat, MA TI Strangeness in the nucleon SO PARITY VIOLATION IN ATOMS AND POLARIZED ELECTRON SCATTERING LA English DT Proceedings Paper CT Workshop on Parity Violation in Atoms and Polarized Electron Scattering CY OCT 27-31, 1997 CL PARIS, FRANCE SP Commiss Energie Atom Saclay, Ecole Normale Superieure, Inst Phys Nucleaire ID ZWEIG-IIZUKA RULE; HEAVY MESONS; QUARK-MODEL; DECAYS; APPROXIMATION; BARYONS AB Simple arguments based on unitarity indicate that met;on loops diagrams, induced by an underlying q (q) over bar pair creation process, should badly disturb the phenomenologically successful spectroscopy and dynamics of the valence quark model, including such simple but mysterious regularities as the OZI rule. I will discuss some recent progress in adding pair creation to the valence quark model in a way which provides a rationale for the quark model's success. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Isgur, N (reprint author), Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 30 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 981-02-3731-6 PY 1999 BP 168 EP 187 PG 20 WC Physics, Particles & Fields SC Physics GA BQ19E UT WOS:000087439800006 ER PT B AU Dunford, RW Stohlker, T AF Dunford, RW Stohlker, T BE Frois, B Bouchiat, MA TI PNC in hydrogen. Different prospects using heliumlike ions SO PARITY VIOLATION IN ATOMS AND POLARIZED ELECTRON SCATTERING LA English DT Proceedings Paper CT Workshop on Parity Violation in Atoms and Polarized Electron Scattering CY OCT 27-31, 1997 CL PARIS, FRANCE SP Commiss Energie Atom Saclay, Ecole Normale Superieure, Inst Phys Nucleaire ID PARITY NON-CONSERVATION; NONCONSERVATION; VIOLATION; ATOMS; STATES AB The motivation for parity experiments in simple atomic systems is that the atomic physics is known precisely so they directly test the weak interactions. We review the status of the parity experiments that have been done in atomic hydrogen and suggest some possibilities for experiments in heliumlike ions. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Dunford, RW (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 28 TC 2 Z9 2 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 981-02-3731-6 PY 1999 BP 356 EP 363 PG 8 WC Physics, Particles & Fields SC Physics GA BQ19E UT WOS:000087439800015 ER PT B AU Zolotorev, M Budker, D AF Zolotorev, M Budker, D BE Frois, B Bouchiat, MA TI Prospects in hydrogenic ions using high-energy accelerators SO PARITY VIOLATION IN ATOMS AND POLARIZED ELECTRON SCATTERING LA English DT Proceedings Paper CT Workshop on Parity Violation in Atoms and Polarized Electron Scattering CY OCT 27-31, 1997 CL PARIS, FRANCE SP Commiss Energie Atom Saclay, Ecole Normale Superieure, Inst Phys Nucleaire ID PARITY-NONCONSERVATION; ATOMIC DYSPROSIUM; HEAVY-IONS; VIOLATION AB Possibilities of precision weak-interaction measurements in relativistic hydrogenic ions are considered. It is shown that using high-energy ion storage rings (RHIC, SPS, LHC), and utilizing relativistic Doppler tuning and laser cooling, it is possible to achieve sensitivity necessary for testing physics beyond the Standard Model. C1 EO Lawrence Berkeley Natl Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. RP Zolotorev, M (reprint author), EO Lawrence Berkeley Natl Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. NR 28 TC 1 Z9 1 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 981-02-3731-6 PY 1999 BP 364 EP 378 PG 15 WC Physics, Particles & Fields SC Physics GA BQ19E UT WOS:000087439800016 ER PT J AU Kim, ES AF Kim, ES TI Simulation of tail distributions for KEKB SO PARTICLE ACCELERATORS LA English DT Article DE colliding beams; particle dynamics; storage rings AB A simulation that uses a new method to obtain tail distributions in electron-positron storage rings has been applied to KEKB. This program makes it possible to investigate the tail distribution using a simple and fast simulation method and shows good agreement with solvable cases. The simulation shows beam-tail distributions due to transverse and longitudinal rare random processes. A six-dimensional beam-beam interaction is considered. The lifetime of the electron beam in KEKB due to rare random processes and beam-beam interaction is estimated to be 5 h. C1 KEK, High Energy Accelerator Res Org, Ibaraki, Osaka 305, Japan. RP Kim, ES (reprint author), LBNL, Ctr Beam Phys, 1 Cyclotron Load,MS 71-259, Berkeley, CA 94720 USA. NR 7 TC 2 Z9 2 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 0031-2460 J9 PART ACCEL JI Part. Accel. PY 1999 VL 63 IS 1 BP 1 EP 19 PG 19 WC Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Nuclear Science & Technology; Physics GA 193YF UT WOS:000080164800001 ER PT S AU Gupta, R AF Gupta, R BE DOlivo, JC Castro, GL Mondragon, M TI Lattice QCD SO PARTICLES AND FIELDS SE AIP Conference Proceedings LA English DT Proceedings Paper CT VIIIth Mexican School on Particles and Fields CY NOV 20-28, 1998 CL OAXACA DE JUAREZ, MEXICO SP Ctr Investigac Estudios Avanzados, Ctr Latinoamer Fisica, Ctr Latinoamer Fisica, Mexico, Consejo Nacl Ciencia Tecnol, European Lab Particle Phys, Estado Oaxaca, Secretaria Turismo, Univ Autonoma Benito Juarez Oaxaca, Univ Nacl Autonoma Mexico ID PERTURBATION-THEORY; CHIRAL-SYMMETRY; WILSON FERMIONS; NONPERTURBATIVE RENORMALIZATION; B-MESON; OPERATORS; IMPROVEMENT; DELTA-S=2; CONTINUUM; DECAY C1 Los Alamos Natl Lab, Grp T8, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Grp T8, Mail Stop B-285, Los Alamos, NM 87545 USA. EM rajan@lanl.gov NR 50 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 1-56396-895-9 J9 AIP CONF PROC PY 1999 VL 490 BP 3 EP 9 PG 7 WC Physics, Particles & Fields SC Physics GA BP14A UT WOS:000084220800001 ER PT J AU Briggs, A Hwang, CC Massoudi, M AF Briggs, A Hwang, CC Massoudi, M TI Flow of a dense particulate mixture using a modified form of the mixture theory SO PARTICULATE SCIENCE AND TECHNOLOGY LA English DT Article ID GRANULAR-MATERIALS; CONTINUUM THEORY; MOTION; PARTICLE; SPHERES; PIPE AB The objective of this work is to study the effect of the relative densities of the components in fluid-solid mixture using the formulation presented in Johnson et at., (1991 a,b). The mixture theory is modified to include the effect of buoyancy forces; for this purpose we introduce a term, A(6) v gradp, in the mechanical interaction between mixture components. When coefficient Ag is zero, We recover the results presented in Johnson et al., (1991 a,b). It is expected to see settling of the solid particles toward the lower plate which is normally related to the "buoyancy effect" in solid-fluid mixtures. Equations for two-component flows are used to analyze Poiseuille flow between two parallel plates. A review of the basic principles of the mixture theory is presented. The equations for the stress tensor of each component of the mixture and the interactions between the components are given. Flow of a fluid-solid mixture between plates is presented with numerical methods and results. C1 Univ Pittsburgh, Dept Mech Engn, Pittsburgh, PA 15261 USA. US DOE, Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. RP Briggs, A (reprint author), Univ Pittsburgh, Dept Mech Engn, Pittsburgh, PA 15261 USA. NR 48 TC 4 Z9 4 U1 0 U2 0 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0272-6351 J9 PARTICUL SCI TECHNOL JI Part. Sci. Technol. PD JAN-JUN PY 1999 VL 17 IS 1-2 BP 1 EP 27 DI 10.1080/02726359908906803 PG 27 WC Engineering, Chemical SC Engineering GA 238LF UT WOS:000082711200001 ER PT J AU Phuoc, TX Massoudi, M AF Phuoc, TX Massoudi, M TI A numerical study of the flow of granular materials between two vertical flat plates which are at different temperatures SO PARTICULATE SCIENCE AND TECHNOLOGY LA English DT Article ID CONTINUUM THEORY; HEAT-TRANSFER AB The present study considers an assembly of spherical particles, densely packed, between two vertical flat plates which are at different temperatures. A continuum model is used and the now due to such a temperature difference is investigated. For a fully developed flow of these materials, the governing equations reduce to a system of coupled, non-linear ordinary differential equations. The equations are integrated numerically. In so doing, the equations are discretized using the conventional central finite difference approximation technique and the unknown conditions are assumed to reduce the problem to an initial value problem. After the trial solutions the known boundary conditions at the edge of the integration interval are compared with the correspondent values provided by the trial solutions. If the solutions at this point do not agree with the known boundary conditions the Newton-Raphson method is used to correct the initial guesses and the iteration is repeated. This procedure continues until the solutions converge to the given values. The technique is found to be powerful for this type of application. C1 US DOE, Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. RP Phuoc, TX (reprint author), US DOE, Fed Energy Technol Ctr, POB 10940,MS 84-340, Pittsburgh, PA 15236 USA. NR 17 TC 1 Z9 1 U1 0 U2 2 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0272-6351 J9 PARTICUL SCI TECHNOL JI Part. Sci. Technol. PD JAN-JUN PY 1999 VL 17 IS 1-2 BP 149 EP 163 DI 10.1080/02726359908906810 PG 15 WC Engineering, Chemical SC Engineering GA 238LF UT WOS:000082711200008 ER PT S AU Gopalsami, N Raptis, AC AF Gopalsami, N Raptis, AC BE Smith, RM TI Millimeter-wave imaging of thermal and chemical signatures SO PASSIVE MILLIMETER-WAVE IMAGING TECHNOLOGY III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Passive Millimeter-Wave Imaging Technology III CY APR 07, 1999 CL ORLANDO, FL SP Soc Photo Opt Instrumentat Engineers DE millimeter-wave imaging; radiometer; spectroscopy; remote sensing AB Development of a passive millimeter-wave (mm-wave) system is described for remotely mapping thermal and chemical signatures of process effluents with application to arms control and nonproliferation. Because a large amount of heat is usually dissipated in the air or waterway as a by-product of most weapons of mass destruction facilities, remote thermal mapping may be used to detect concealed or open facilities of weapons of mass destruction. We have developed a focal-plane mm-wave imaging system to investigate the potential of thermal mapping. Results of mm-wave images obtained with a 160-GHz radiometer system are presented for different target scenes simulated in the laboratory. Chemical and nuclear facilities may be identified by remotely measuring molecular signatures of airborne molecules emitted from these facilities. We have developed a filterbank radiometer to investigate the potential of passive spectral measurements. Proof of principle is presented by measuring the HDO spectral line at 80.6 GHz with a 4-channel 77-83 GHz radiometer. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Gopalsami, N (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 5 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 0-8194-3177-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3703 BP 130 EP 138 DI 10.1117/12.352998 PG 9 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BN53H UT WOS:000082158200014 ER PT B AU Son, KA Missert, N Barbour, JC Hren, JJ Copeland, RG Minor, KG AF Son, KA Missert, N Barbour, JC Hren, JJ Copeland, RG Minor, KG BE Seo, M MacDougall, B Takahashi, H Kelly, RG TI Growth and oxidation of thin film Al2Cu SO PASSIVITY AND LOCALIZED CORROSION: AN INTERNATIONAL SYMPOSIUM IN HONOR OF PROFESSOR NORIO SATO SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Joint International Meeting of the Electrochemical-Society-Inc and the Electrochemical-Society-of-Japan CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Div Corros, Electrochem Soc Inc, Electrochem Soc Japan ID AL-CU; INTERMETALLIC PHASES; CORROSION; ALUMINUM; ALLOYS AB Al2Cu thin films (similar to 382 nm) are fabricated by melting and resolidifying Al/Cu bilayers in the presence of a similar to 3 nm Al2O3 passivating layer. X-ray Photoelectron Spectroscopy (XPS) measures a 1.0 eV shift of the Cu(2)p(3/2) peak and a 1.6 eV shift of the valance band relative to metallic Cu upon Al2Cu formation. Scanning Electron Microscopy (SEM) and Electron Back-Scattered Diffraction (EBSD) show that the Al2Cu film is composed of 30-70 mu m wide and 10-25 mm long cellular grains with (110) orientation. The atomic composition of the film as estimated by Energy Dispersive Spectroscopy (EDS) is 67+/-2% Al and 33+/-2% Cu. XPS scans of Al2O3/Al2Cu taken before and after air exposure indicate that the upper Al2Cu layers undergo further oxidation to Al2O3 even in the presence of similar to 5 nm Al2O3. The majority of Cu produced from oxidation is believed to migrate below the Al2O3 layers, based upon the lack of evidence for metallic Cu in the XPS scans. In contrast to Al/Cu passivated with Al2O3, melting/resolidifying the Al/Cu bilayer without Al2O3 results in phase-segragated dendritic film growth. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Son, KA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-250-8 J9 ELEC SOC S PY 1999 VL 99 IS 27 BP 75 EP 83 PG 9 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA BP90P UT WOS:000086563500008 ER PT B AU Isaacs, HS Xu, F Jeffcoate, CS AF Isaacs, HS Xu, F Jeffcoate, CS BE Seo, M MacDougall, B Takahashi, H Kelly, RG TI Dissolution of oxide films on aluminum in near neutral solutions SO PASSIVITY AND LOCALIZED CORROSION: AN INTERNATIONAL SYMPOSIUM IN HONOR OF PROFESSOR NORIO SATO SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Joint International Meeting of the Electrochemical-Society-Inc and the Electrochemical-Society-of-Japan CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Div Corros, Electrochem Soc Inc, Electrochem Soc Japan AB Simple linear potentiodynamic cycling measurements have been made on abraded pure Al in berate, chromate, phosphate, sulfate and nitrate solutions. In borate and chromate solutions the currents continued to decrease with each subsequent cycle. In phosphate dissolution of the oxide takes place producing repetitive repeat curves. The current variations in berate and chromate were simulated using a high field conduction oxide growth model. Including oxide dissolution in the model simulated the polarization behavior in phosphate. Results in sulfate and nitrate solutions were more complex. The behavior in the sulfate solution was attributed to effects of sulfate the oxide/solution interface. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Isaacs, HS (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-250-8 J9 ELEC SOC S PY 1999 VL 99 IS 27 BP 310 EP 316 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA BP90P UT WOS:000086563500033 ER PT B AU Wall, FD AF Wall, FD BE Seo, M MacDougall, B Takahashi, H Kelly, RG TI Current-limited imposed-potential technique for inducing and monitoring metastable pitting events SO PASSIVITY AND LOCALIZED CORROSION: AN INTERNATIONAL SYMPOSIUM IN HONOR OF PROFESSOR NORIO SATO SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Joint International Meeting of the Electrochemical-Society-Inc and the Electrochemical-Society-of-Japan CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Div Corros, Electrochem Soc Inc, Electrochem Soc Japan ID STAINLESS-STEEL; LOCALIZED CORROSION AB A technique has been developed to selectively induce metastable pitting while preventing the transition to stable pit growth. The current-limited imposed-potential (CLIP) technique limits available cathodic current to an initiated site using a resistor in series with the working electrode to form a voltage divider. Potentiodynamic CLIP testing yields a distribution of breakdown potentials from a single experiment. Potentiostatic CLIP testing yields induction time data, which can be used as input to a calculation of germination rate. Initial data indicate that a one-to-one correlation exists between electrochemical transients and observed pitting sites. The CLIP technique provides a consistent means of gathering quantitative potential and current transients associated with localized oxide breakdown. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wall, FD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-250-8 J9 ELEC SOC S PY 1999 VL 99 IS 27 BP 387 EP 396 PG 10 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA BP90P UT WOS:000086563500042 ER PT B AU Lillard, JA Bingert, JF Kolman, DG AF Lillard, JA Bingert, JF Kolman, DG BE Seo, M MacDougall, B Takahashi, H Kelly, RG TI Morphology of pits in nickel: Anisotropic growth due to crystallographic orientation SO PASSIVITY AND LOCALIZED CORROSION: AN INTERNATIONAL SYMPOSIUM IN HONOR OF PROFESSOR NORIO SATO SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Joint International Meeting of the Electrochemical-Society-Inc and the Electrochemical-Society-of-Japan CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Div Corros, Electrochem Soc Inc, Electrochem Soc Japan ID MECHANISM AB Anisotropic pit growth was observed in high-purity, polycrystalline nickel during anodic polarization scans in an acidic chloride-sulfate solution. Pits initiated at triple points and had perforated covers. Sometimes all of the pit growth was into one grain, while at other times growth was into all three grains surrounding the triple point. The pattern of perforations in pit covers gave an indication to the pattern of growth. Near the initiation point, perforations formed concentric circles, which suggested that initial growth was dominated by local solution chemistry. Away from the initiation point, the perforation pattern suggested that crystallographic orientation and grain boundaries had a significant effect oil pit growth. In single crystal nickel, pits had perforated covers and pit shape was directly related to the crystallographic orientation. Pits were hexagonal on the {111} face, square on the {100} face, and had a blunted diamond shape on the {110} face. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Lillard, JA (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-250-8 J9 ELEC SOC S PY 1999 VL 99 IS 27 BP 453 EP 462 PG 10 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA BP90P UT WOS:000086563500049 ER PT B AU Kolman, DG Butt, DP AF Kolman, DG Butt, DP BE Seo, M MacDougall, B Takahashi, H Kelly, RG TI Pitting behavior of a novel SiC/Al2O3/Al composite exposed to chloride environments SO PASSIVITY AND LOCALIZED CORROSION: AN INTERNATIONAL SYMPOSIUM IN HONOR OF PROFESSOR NORIO SATO SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Joint International Meeting of the Electrochemical-Society-Inc and the Electrochemical-Society-of-Japan CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Div Corros, Electrochem Soc Inc, Electrochem Soc Japan ID METAL-MATRIX COMPOSITES; CORROSION BEHAVIOR; ALUMINUM-ALLOY AB The electrochemical behavior of a new class of aluminum metal matrix composites produced by the direct metal oxidation technique, Lanxide AS-109(TM), was detailed. The composite is 69% (by volume) SiC reinforcement, 24% oxidized metal (primarily Al2O3), and 7% retained aluminum alloy. The corrosion behavior of the SiC/Al2O3/Al composite was found to be dependent on NaCl concentration and pH. SiC/Al2O3/Al was susceptible to pitting of the Al alloy phase at open circuit during exposure to aerated and deaerated 0.6, 0.06, and 0.006 M NaCl solutions. In contrast, exposure to 6x10(-4) M NaCl did not result in pitting at open circuit, and buffered berate solution (no chloride) did not yield pitting at any potential examined. The pitting potential of SiC/Al2O3/Al was estimated to decrease 80 mV per order of magnitude increase in NaCl concentration. Comparison of the composite to a model composite matrix material, Al 6061, revealed that the composite was more susceptible to localized corrosion than the matrix alloy alone which did not pit at open circuit in deaerated 0.6 M NaCl. Polarization resistance measurements in pH adjusted(1 - 13) 0.6 M NaCl solutions revealed that the corrosion rate is minimized in neutral solution. Pits were neither confined to regions adjacent to SiC nor Al2O3, suggesting little galvanic effect of the reinforcing phases. C1 Univ Calif Los Alamos Natl Lab, Mat Corros & Environm Effects Lab, Los Alamos, NM 87545 USA. RP Kolman, DG (reprint author), Univ Calif Los Alamos Natl Lab, Mat Corros & Environm Effects Lab, POB 1663, Los Alamos, NM 87545 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-250-8 J9 ELEC SOC S PY 1999 VL 99 IS 27 BP 463 EP 472 PG 10 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA BP90P UT WOS:000086563500050 ER PT S AU Bruckner-Lea, CJ Holman, DA Schuck, BL Brockman, FJ Chandler, DP AF Bruckner-Lea, CJ Holman, DA Schuck, BL Brockman, FJ Chandler, DP BE Chen, YR TI Strategies for automated sample preparation, nucleic acid purification, and concentration of low target number nucleic acids in environmental and food processing samples SO PATHOGEN DETECTION AND REMEDIATION FOR SAFE EATING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Pathogen Detection and Remediation for Safe Eating CY NOV 05, 1998 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers DE nucleic acid; DNA; flow injection analysis; hybridization; pathogen detection ID FLOW-INJECTION AB The purpose of this work is to develop a rapid, automated system for nucleic acid purification and concentration from environmental and food processing samples. Our current approach involves off-line filtration and cell lysis (ballistic disintegration) functions in appropriate buffers followed by automated nucleic acid capture and purification on renewable affinity matrix microcolumns. Physical cell lysis and renewable affinity microcolumns eliminate the need for toxic organic solvents, enzyme digestions or other time-consuming sample manipulations. Within the renewable affinity microcolumn, we have examined nucleic acid capture and purification efficiency with various microbead matrices (glass, polymer, paramagnetic), surface derivatization (sequence-specific capture oligonucleotides or peptide nucleic acids), and DNA target size and concentration under variable solution conditions and temperatures. Results will be presented comparing automated system performance relative to benchtop procedures for both clean (pure DNA from a laboratory culture) and environmental (soil extract) samples, including results which demonstrate 8 minute purification and elution of low-copy nucleic acid targets from a crude soil extract in a form suitable for PCR or microarray-based detectors. Future research will involve the development of improved affinity reagents and complete system integration, including upstream cell concentration and cell lysis functions and downstream, gene-based detectors. Results of this research will ultimately lead to improved processes and instrumentation for on-line, automated monitors for pathogenic microorganisms in food, water, air, and soil samples. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Bruckner-Lea, CJ (reprint author), Battelle Mem Inst, Pacific NW Labs, Mailstop K8-93, Richland, WA 99352 USA. NR 10 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 0-8194-3005-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3544 BP 63 EP 71 DI 10.1117/12.335782 PG 9 WC Food Science & Technology; Optics SC Food Science & Technology; Optics GA BM42Y UT WOS:000078691500007 ER PT S AU Wolford, JK MacArthur, DW AF Wolford, JK MacArthur, DW BE Doty, FP TI Safeguards for nuclear material transparency monitoring SO PENETRATING RADIATION SYSTEMS AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Penetrating Radiation Systems and Applications CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE safeguards; radiation detection; data security; arms control AB The US and the Russian Federation are currently engaged in negotiating or implementing several nuclear arms and nuclear material control agreements. These involve placing nuclear material in specially designed containers within controlled facilities. Some of the agreements require the removal of nuclear components from stockpile weapons. These components are placed in steel containers that are then sealed and tagged. Current strategies for monitoring the agreements involve taking neutron and gamma radiation measurements of components in their containers to monitor the presence, mass, and composition of plutonium or highly enriched uranium, as well as other attributes that indicate the use of the material in a weapon. If accurate enough to be useful, these measurements will yield data containing information about the design of the weapon being monitored. In each case, the design data are considered sensitive by one or both parties to the agreement. To prevent the disclosure of this information in a bilateral or trilateral inspection scenario, so-called information barriers have evolved. These barriers combine hardware, software, and procedural safeguards to contain the sensitive data within a protected volume, presenting to the inspector only the processed results needed for verification. Interlocks and volatile memory guard against disclosure in case of failure. Implementing these safeguards requires innovation in radiation measurement instruments and data security. Demonstrating their reliability requires independent testing to uncover any flaws in design. This study discusses the general problem and gives a proposed solution for a high resolution gamma ray detection system. It uses historical examples to illustrate the evolution of other successful systems. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Wolford, JK (reprint author), Univ Calif Lawrence Livermore Natl Lab, MS L-183, Livermore, CA 94551 USA. NR 10 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 0-8194-3255-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3769 BP 2 EP 10 PG 9 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA BN95H UT WOS:000083637700001 ER PT S AU Roney, TJ White, TA Pink, RJ Smith, M Jones, WF AF Roney, TJ White, TA Pink, RJ Smith, M Jones, WF BE Doty, FP TI Portable gamma-ray transmission system for identification of chemical agents SO PENETRATING RADIATION SYSTEMS AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Penetrating Radiation Systems and Applications CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE gamma ray; attenuation; tomography; material identification AB A field-portable instrument has been developed for the purpose of classifying and identifying chemical agents within munitions by measurement of the linear attenuation property of the agent. For most chemical agents of interest, the gamma-ray linear attenuation coefficient is sufficient to separate the agents by class (nerve, blister, and blood). In addition, many chemical agents of a particular class are separable by the attenuation coefficient. Complications in gamma ray transmission measurements arise due to the packaging of the chemical agents in thick-walled steel containers of various configurations, corrosion, and changes in the state of the material from liquid to solid or gas. Identification of chemical agents within a container and without imaging is contingent upon sampling a region of the container that has a homogeneous distribution of the agent. The instrument allows for several degrees of freedom to accommodate multiple data acquisition protocols, including tomographic imaging. A variety of algorithms have been investigated including single-ray transmission to complete 2D-computed tomography using a collimated isotopic source. Recent results indicate that gamma ray measurements can provide identification of chemical agents in reasonable time frames. This paper will describe the system, data acquisition and processing, and present results from laboratory and field studies. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Roney, TJ (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. NR 7 TC 1 Z9 1 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 0-8194-3255-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3769 BP 11 EP 23 DI 10.1117/12.363676 PG 13 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA BN95H UT WOS:000083637700002 ER PT S AU Morgan, J Ignatyev, G Seminov, D Chernov, M AF Morgan, J Ignatyev, G Seminov, D Chernov, M BE Doty, FP TI A gamma-ray camera for arms control applications SO PENETRATING RADIATION SYSTEMS AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Penetrating Radiation Systems and Applications CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE gamma ray; Compton scattering; transparency; fissile material AB The Research Institute of Pulse Techniques, in collaboration with the Proliferation Prevention and Arms Control Program at Lawrence Livermore National Laboratory, has constructed a gamma-ray camera for use in arms control agreements such as Mutual Reciprocal Inspections and Warhead Dismantlement Transparency. The camera is designed to have high efficiency (in order to reduce inspection times), moderate resolution (to decrease the intrusiveness of the measurements), and sturdy construction (to allow operation in the types of conditions that might be met during shipment and use at various forward weapons sites). The imaging element consists of a honeycomb or soda-straw lead collimator and a 312-mm-diameter NaI(TI) scintillator viewed by an array of phototubes. Software was developed to display two- and three-dimensional views of the data and to analyze shape and peak areas. The first model was tuned for plutonium radiation in the 375- to 415-keV energy range. Images from various arrays of point sources were obtained and will be presented. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94330 USA. RP Morgan, J (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-186, Livermore, CA 94330 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 0-8194-3255-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3769 BP 24 EP 30 DI 10.1117/12.363686 PG 7 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA BN95H UT WOS:000083637700003 ER PT S AU Hall, J Dietrich, F Logan, C Schmid, G AF Hall, J Dietrich, F Logan, C Schmid, G BE Doty, FP TI Development of high-energy neutron imaging for use in NDE applications SO PENETRATING RADIATION SYSTEMS AND APPLICATIONS SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Penetrating Radiation Systems and Applications CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE neutron imaging; neutron radiography; computed tomography; non-destructive inspection; neutron sources ID VACUUM-ATMOSPHERE INTERFACE; ION MATERIAL MODIFICATION; PLASMA WINDOW; RADIOGRAPHY; LENS AB We are currently developing a high-energy (10 - 15 MeV) neutron imaging system for use in NDE applications. Our goal is to develop an imaging system capable of detecting cubic-mm-scale voids or other structural defects in heavily-shielded low-Z materials within thick sealed objects. The system will be relatively compact (suitable for use in a small laboratory) and capable of acquiring tomographic image data sets. The design of a prototype imaging detector and multi-axis staging system will be discussed and selected results from recent imaging experiments will be presented. The development of an intense, accelerator-driven neutron source suitable for use with the imaging system will also be discussed. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Hall, J (reprint author), Lawrence Livermore Natl Lab, POB 808,MS L-050, Livermore, CA 94551 USA. EM jmhall@llnl.gov NR 41 TC 8 Z9 10 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 0-8194-3255-5 J9 PROC SPIE PY 1999 VL 3769 BP 31 EP 42 DI 10.1117/12.363690 PG 12 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA BN95H UT WOS:000083637700004 ER PT S AU Parker, WE Buckley, WM Kreek, SA Caffrey, AJ Mauger, GJ Lavietes, AD Dougan, AD AF Parker, WE Buckley, WM Kreek, SA Caffrey, AJ Mauger, GJ Lavietes, AD Dougan, AD BE Doty, FP TI A portable system for nuclear, chemical agent and explosives identification SO PENETRATING RADIATION SYSTEMS AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Penetrating Radiation Systems and Applications CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE portable radiation detector technology; chemical weapons; explosive device identification; contraband detection; airport and public works safety AB The FRIS/PINS hybrid integrates the LLNL-developed Field Radionuclide Identification System (FRIS) with the INEEL-developed Portable Isotopic Neutron Spectroscopy (PINS) chemical assay system to yield a combined general radioisotope, special nuclear material (SNM), and chemical weapons/explosives (CWE) detection and identification system. The PINS system uses a neutron source and a high-purity germanium gamma-ray detector. The FRIS system uses an electromechanically cooled germanium detector and its own analysis software to detect and identify SNM and other radioisotopes. The FRIS/PINS combined system also uses the electromechanically-cooled germanium detector. There is no other currently available integrated technology that can combine an active neutron interrogation and analysis capability for CWE with a passive radioisotope measurement and identification capability for SNM. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Parker, WE (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. RI Caffrey, Augustine/C-2005-2009 NR 9 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 0-8194-3255-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3769 BP 43 EP 50 DI 10.1117/12.363678 PG 8 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA BN95H UT WOS:000083637700005 ER PT S AU Earnhart, JRD Prettyman, TH Ianakiev, KD Gardner, RP AF Earnhart, JRD Prettyman, TH Ianakiev, KD Gardner, RP BE Doty, FP TI Evaluation of the Compton camera method for spectroscopic imaging with ambient-temperature detector technology SO PENETRATING RADIATION SYSTEMS AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Penetrating Radiation Systems and Applications CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE gamma ray imaging; Compton camera; nuclear material safeguards ID EMISSION COMPUTED-TOMOGRAPHY; COLLIMATED GAMMA-CAMERA; SCATTER CAMERA; DESIGN AB A prototype Compton camera using ambient-temperature semiconductor detectors is developed for gamma ray spectroscopic imaging. Two camera configurations are evaluated, one using an intrinsic silicon detector for the front plane detector and the other using a CdZnTe detector for the front plane. Both configurations use a large-volume coplanar grid CdZnTe detector for the back plane. The effect of detector noise, energy resolution, and timing resolution on camera performance is described. Technical issues underlying the development of Compton cameras for spectroscopic imaging are presented and imaging of radioactive sources is demonstrated. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Earnhart, JRD (reprint author), Univ Calif Los Alamos Natl Lab, MS E540, Los Alamos, NM 87545 USA. OI Prettyman, Thomas/0000-0003-0072-2831 NR 15 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 0-8194-3255-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3769 BP 76 EP 87 DI 10.1117/12.363668 PG 12 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA BN95H UT WOS:000083637700009 ER PT S AU Hutchinson, DP Richards, RK Holcomb, DE Ramsey, JA AF Hutchinson, DP Richards, RK Holcomb, DE Ramsey, JA BE Doty, FP TI Position sensitive scintillation neutron detectors using a crossed-fiber optic readout array SO PENETRATING RADIATION SYSTEMS AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Penetrating Radiation Systems and Applications CY JUL 19-23, 1999 CL DENVER, CO SP SPIE AB The Spallation Neutron Source (SNS) under construction at the Oak Ridge National Laboratory will be the most important new neutron scattering facility in the United States, Neutron scattering instruments for the SNS will require large area detectors with fast response (< 1 microsecond), high efficiency over a wide range of neutron energies (0.1 to 10 eV), and low gamma ray sensitivity. We are currently developing area neutron detectors based on a combination of (LiF)-Li-6/ZnS scintillator screens coupled to a wavelength-shifting fiber optic readout array. A 25 x 25-cm prototype detector is currently under development. Initial tests at the High Flux Isotope Reactor have demonstrated good imaging properties coupled with very low gamma ray sensitivity. In addition, we have developed a multi-layer scintillator/fiber detector to replace existing He-3 gas detector tubes for higher speed operation. This detector has demonstrated a neutron detection efficiency of over 75% at a neutron energy of 0.056 eV or about twice thermal. The response time of this detector is approximately 1 microsecond. Details of the design and test results of both detectors will be presented. C1 Oak Ridge Natl Lab, Div Instrumentat & Controls, Oak Ridge, TN 37831 USA. RP Hutchinson, DP (reprint author), Oak Ridge Natl Lab, Div Instrumentat & Controls, Oak Ridge, TN 37831 USA. OI Holcomb, David/0000-0001-8263-4661 NR 1 TC 7 Z9 7 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 0-8194-3255-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3769 BP 88 EP 91 DI 10.1117/12.363669 PG 4 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA BN95H UT WOS:000083637700010 ER PT S AU Fry, DA Claytor, TN Davis, AW Jones, MH Sheats, MJ Stupin, DM Summa, DA White, SM Hefele, J Watson, SA Kauppila, TJ Mueller, KH AF Fry, DA Claytor, TN Davis, AW Jones, MH Sheats, MJ Stupin, DM Summa, DA White, SM Hefele, J Watson, SA Kauppila, TJ Mueller, KH BE Doty, FP TI Recent developments in electronic radiography at Los Alamos SO PENETRATING RADIATION SYSTEMS AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Penetrating Radiation Systems and Applications CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE radiography; amorphous silicon; computed tomography; x-ray; neutron radiography; nondestructive testing; high speed imaging; modeling; simulation ID RAY AB An overview of the radiographic capabilities with emphasis on electronic image detection and processing at the Los Alamos National Laboratory is presented. Fixed facilities and portable x-ray sources and imaging systems make up the Los Alamos capability. Examples of imaging with large area amorphous silicon imaging panels, a portable computed tomography system, high speed x-ray imaging applications and equipment, and small area, high resolution imagers are given. Radiographic simulation and reverse engineering from radiographic images to computer aided design files and solid models is also presented. C1 Univ Calif Los Alamos Natl Lab, Engn Sci & Applicat Div, Measurement Technol Grp, Los Alamos, NM 87545 USA. RP Fry, DA (reprint author), Univ Calif Los Alamos Natl Lab, Engn Sci & Applicat Div, Measurement Technol 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 0-8194-3255-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3769 BP 111 EP 123 DI 10.1117/12.363672 PG 13 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA BN95H UT WOS:000083637700014 ER PT S AU Wehlburg, JC Jacobs, J Shope, SL Lockwood, GJ Selph, MM AF Wehlburg, JC Jacobs, J Shope, SL Lockwood, GJ Selph, MM BE Doty, FP TI Landmine detection using backscattered x-ray radiography SO PENETRATING RADIATION SYSTEMS AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Penetrating Radiation Systems and Applications CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE backscattered x-ray; imaging; mine detection ID LATERAL MIGRATION RADIOGRAPHY; MINES AB The implementation of a backscattered x-ray landmine detection system has been demonstrated in laboratories at both Sandia National Laboratories (SNL) and the University of Florida (UF.) The next step was to evaluate the modality by assembling a system for fieldwork and to evaluate the systems performance with real landmines. To assess the system's response to a variety of objects, buried simulated plastic and metal antitank landmines, surface simulated plastic antipersonnel landmines, and surface metal fragments were used as targets for the field test. The location of the test site was an unprepared field at SNL. The tests conducted using real landmines were held at UF using various burial depths. The field tests yielded the same levels of discrimination between soil and landmines that had been detected in laboratory experiments. The tests on the real landmines showed that the simulated landmines were a good approximation. The real landmines also contained internal features that would allow not only the detection of the landmines, but also the identification of them. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wehlburg, JC (reprint author), Sandia Natl Labs, MS 0980, Albuquerque, NM 87185 USA. NR 6 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 0-8194-3255-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3769 BP 149 EP 154 DI 10.1117/12.363675 PG 6 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA BN95H UT WOS:000083637700017 ER PT S AU Mauger, GJ Parker, WE Lavietes, AD Bandong, BB Friensehner, AV Lanier, RG Raschke, KE AF Mauger, GJ Parker, WE Lavietes, AD Bandong, BB Friensehner, AV Lanier, RG Raschke, KE BE Doty, FP TI Radiation detection in a marine environment SO PENETRATING RADIATION SYSTEMS AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Penetrating Radiation Systems and Applications CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE portable radiation detector technology; marine radiation detection AB We have performed radiation detection measurements to explore the feasibility of radioisotopic analysis and detection of a neutron source in a marine environment. We determined the maximum range in seawater through which complex gamma-ray emitting materials could be accurately assayed for isotopic content. Additionally we used the gamma rays from neutron capture on chlorine to detect a neutron source. Results from our experiments have been used to determine the greatest distance at which the presence of a neutron emitter can be confirmed. The measurements used an electromechanically-cooled high-purity germanium detector system in both laboratory and fielded seawater conditions. The laboratory experiments used a variety of sources in an arrangement where both the source and detector were surrounded by seawater. The field experiments were performed underwater with the detector in a sealed container that was separate from the source. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Mauger, GJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 2 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 0-8194-3255-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3769 BP 196 EP 205 DI 10.1117/12.363682 PG 10 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA BN95H UT WOS:000083637700022 ER PT S AU Vaniman, D Bish, D Guthrie, G Chipera, S Blake, D Collins, SA Elliott, ST Sarrazin, P AF Vaniman, D Bish, D Guthrie, G Chipera, S Blake, D Collins, SA Elliott, ST Sarrazin, P BE Doty, FP TI Process monitoring and control with CHEMIN, a miniaturized CCD-based instrument for simultaneous XRD/XRF analysis SO PENETRATING RADIATION SYSTEMS AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Penetrating Radiation Systems and Applications CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE X-ray diffraction; X-ray fluorescence; CCD; mineralogy; process control AB There is a large variety of mining and manufacturing operations where process monitoring and control can benefit from onsite analysis of both chemical and mineralogic constituents. CHEMIN is a CCD-based instrument capable of both X-ray fluorescence (XRF; chemical) and X-ray diffraction (XRD; mineralogic) analysis. Monitoring and control with an instrument like CHEMIN can be applied to feedstocks, intermediate materials, and final products to optimize production. Examples include control of cement feedstock, of ore for smelting, and of minerals that pose inhalation hazards in the workplace. The combined XRD/XRF capability of CHEMIN can be used wherever a desired commodity is associated with unwanted constituents that may be similar in chemistry or structure but not both (e.g., Ca in both gypsum and feldspar, where only the gypsum is desired to make wallboard). In the mining industry, CHEMIN can determine mineral abundances on the spot and enable more economical mining by providing the means to assay what is being mined, quickly and frequently, at minimal cost. In manufacturing, CHEMIN could be used to spot-check the chemical composition and crystalline makeup of a product at any stage of production. Analysis by CHEMIN can be used as feedback in manufacturing processes where rates of heating, process temperature, mixture of feedstocks, and other variables must be adjusted in real time to correct structure and/or chemistry of the product (e.g., prevention of periclase and alkali sulfate coproduction in cement manufacture). C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Vaniman, D (reprint author), Univ Calif Los Alamos Natl Lab, MS D462, Los Alamos, NM 87545 USA. NR 11 TC 0 Z9 0 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 0-8194-3255-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3769 BP 243 EP 251 DI 10.1117/12.363687 PG 9 WC Imaging Science & Photographic Technology SC Imaging Science & Photographic Technology GA BN95H UT WOS:000083637700027 ER PT B AU Loftin, SR White, CS AF Loftin, SR White, CS BE Eldridge, D Freudenberger, D TI Restoration of degraded grasslands with fire: effects on vegetation SO PEOPLE AND RANGELANDS BUILDING THE FUTURE, VOLS 1 AND 2 LA English DT Proceedings Paper CT VIth International Rangeland Congress CY JUL 19-23, 1999 CL TOWNSVILLE, AUSTRALIA SP USDA ARS, USDA Forest Serv, USDA Nat Resources Conservat Serv, US Dept Interior Bur Land Management, Australian Fed Consortium, Agr Fisheries & Forestry, Australian Fed Consortium Rural Ind Res & Dev Corp, Cooperative Res Ctr Sustainable Dev Trop Savannas, CSIRO Trop Agr, Dept For Int Dev, FAO, Queensland Dept Primary Ind, Australian Agcy Int Dev, Australian Rangeland Soc, UN Environm Program, Agr, WA, CSIRO Wildlife & Ecol, Grassland Soc SO Africa, NSW Agr, NSW Dept Land & Water Conservat, Soc Range Management, Int Conf Support Scheme, Townsville City Council & Townsville Enterprise, Univ NSW, Univ SO Queensland C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Loftin, SR (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Lujan Center, LANL/G-4896-2012 NR 1 TC 0 Z9 0 U1 1 U2 1 PU VI INT RANGELAND CONGRESS INC PI AITKENVALE PA PO BOX 764, AITKENVALE, QLD 4814, AUSTRALIA BN 0-9577394-0-0 PY 1999 BP 286 EP 286 PG 1 WC Agriculture, Dairy & Animal Science; Plant Sciences; Ecology SC Agriculture; Plant Sciences; Environmental Sciences & Ecology GA BP58M UT WOS:000085573000132 ER PT J AU Hura, G Sorenson, JM Glaeser, RM Head-Gordon, T AF Hura, G Sorenson, JM Glaeser, RM Head-Gordon, T TI Solution X-ray scattering as a probe of hydration-dependent structuring of aqueous solutions SO PERSPECTIVES IN DRUG DISCOVERY AND DESIGN LA English DT Review DE desolvation; energy functions; hydrophobicity; protein folding; solution scattering ID LIQUID WATER; PEPTIDE-FRAGMENTS; BINDING-SITES; PROTEINS; THERMODYNAMICS; DIFFRACTION; INITIATION; DYNAMICS; FORCES; DESIGN AB We report on new X-ray solution scattering experiments and molecular dynamics simulations conducted for increasing solute concentrations of N-acetyl-amino acid-amides and -methylamides in water, for the amino acids leucine, glutamine, and glycine. As the concentration increases, the main diffraction peak of pure water at Q = 2.0 Angstrom(-1) shifts to smaller angle for the larger leucine and glutamine amino acids, and a new diffraction peak grows in at Q similar to 0.8 Angstrom(-1) for only the hydrophobic amino acid leucine. The unaltered value of the peak position at Q similar to 0.8 Angstrom(-1) over a large concentration range suggests that a stable and ordered leucine solute-solute distribution is sustained. Simulations of the distributions of leucines in water that reproduce the experimental observable show that mono-dispersed to small molecular aggregates of two to six hydrophobic amino acids are formed, as opposed to complete segregation of the hydrophobic solutes into one large cluster. The scattering results for the hydrophobic leucine amino acid are contrasted with experiments and simulations of the model hydrophilic side chain glutamine and the model backbone glycine. The self-assembly process of protein folding modeled with these experiments, in particular the condensation to a hydrophobic core, shares similar issues with the desolvation phenomena that are important in drug discovery. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Grad Grp Biophys, Berkeley, CA 94720 USA. RP Hura, G (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. EM TLHead-Gordon@lbl.gov RI Head-Gordon, Teresa/E-5818-2011 NR 46 TC 29 Z9 29 U1 1 U2 5 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0928-2866 J9 PERSPECT DRUG DISCOV JI Perspect. Drug Discov. Design PY 1999 VL 17 IS 1 BP 97 EP 118 DI 10.1023/A:1008778724866 PG 22 WC Chemistry, Medicinal; Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 268EH UT WOS:000084401000006 ER PT J AU Cao, WW AF Cao, WW TI Untitled SO PHASE TRANSITIONS LA English DT Editorial Material C1 Penn State Univ, University Pk, PA 16802 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cao, WW (reprint author), Penn State Univ, University Pk, PA 16802 USA. RI Cao, Wenwu/F-6091-2012 OI Cao, Wenwu/0000-0002-2447-1486 NR 0 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 0141-1594 J9 PHASE TRANSIT JI Phase Transit. PY 1999 VL 69 IS 3 BP I EP II PN B PG 2 WC Crystallography; Physics, Condensed Matter SC Crystallography; Physics GA 249BW UT WOS:000083313100001 ER PT J AU Kerr, WC Killough, MG Saxena, A Swart, PJ Bishop, AR AF Kerr, WC Killough, MG Saxena, A Swart, PJ Bishop, AR TI Role of elastic compatibility in martensitic texture evolution SO PHASE TRANSITIONS LA English DT Article; Proceedings Paper CT Workshop on Nonlinear Phenomena in Transforming Solids held in Honor of the 70th Birthday of Gerhard R Barsch CY JUN 20-21, 1997 CL STATE COLL, PENNSYLVANIA SP Penn St Univ, Los Alamos Natl Lab DE compatibility; Ginzburg-Landau; martensite; textures; tweed; twins ID 2 DIMENSIONS; TRANSFORMATION; PHASE; MICROSTRUCTURES; ALLOY AB We employ the time-dependent Ginzburg-Landau (TDGL) method to analyze the time evolution of strain fields in a model for materials with martensitic phase transformations. The free energy functional is expressed in terms of the components of the strain tensor, and its functional derivatives with respect to these components give their rate of change. However, the components of the strain tensor are not independent fields; rather, they are related by the Saint-Venant compatibility condition. This condition imposes constraints on the variations of the strain tensor components needed to obtain the equations of motion. Incorporating these constraints in the TDGL procedure introduces extra terms that effectively act as long-range, anisotropic elastic interactions. The latter govern the types of elastic textures that may emerge during a martensitic transformation. The results from the numerical solution of these evolution equations exhibit fine and coarse tweed, twinning, and tip-splitting. C1 Wake Forest Univ, Olin Phys Lab, Winston Salem, NC 27109 USA. NYU, Courant Inst Math Sci, New York, NY 10012 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Kerr, WC (reprint author), Wake Forest Univ, Olin Phys Lab, Winston Salem, NC 27109 USA. NR 23 TC 11 Z9 11 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 0141-1594 J9 PHASE TRANSIT JI Phase Transit. PY 1999 VL 69 IS 3 BP 247 EP + DI 10.1080/01411599908209294 PN B PG 27 WC Crystallography; Physics, Condensed Matter SC Crystallography; Physics GA 249BW UT WOS:000083313100003 ER PT J AU Herhold, AB Chen, CC Johnson, CS Tolbert, SH Alivisatos, AP AF Herhold, AB Chen, CC Johnson, CS Tolbert, SH Alivisatos, AP TI Structural transformations and metastability in semiconductor nanocrystals SO PHASE TRANSITIONS LA English DT Article DE metastability; nanocrystal; phase transition; high pressure; kinetics ID HIGH-PRESSURE PHASE; CDSE NANOCRYSTALS; RAMAN-SCATTERING; CRYSTAL STABILITY; SIZE DEPENDENCE; LOW-TEMPERATURE; QUANTUM DOTS; BETA-TIN; TRANSITION; SILICON AB Pressure-induced structural phase transitions have been studied in CdSe, CdS, InP and Si semiconductor nanocrystals. Nanocrystals transform via single nucleation of the phase transition with a kinetic barrier that increases in increasing cluster size. The structural transition path causes a shape change in the nanocrystals, which dictates the surface energy and thus the kinetic and thermodynamic stability of the transformed nanocrystal. These finite size effects can be used to tune the metastability of the nanocrystals versus pressure. Enhanced metastability allows structural and optical measurements in a regime inaccessible to the bulk solid, as well as possible recovery of the dense high pressure phase to atmospheric pressure. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Chen, Chia-Chun/F-7939-2012; Alivisatos , Paul /N-8863-2015; Tolbert, Sarah/L-2321-2016 OI Alivisatos , Paul /0000-0001-6895-9048; NR 73 TC 12 Z9 12 U1 0 U2 20 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND SN 0141-1594 EI 1029-0338 J9 PHASE TRANSIT JI Phase Transit. PY 1999 VL 68 IS 1 BP 1 EP 25 DI 10.1080/01411599908224513 PN B PG 25 WC Crystallography; Physics, Condensed Matter SC Crystallography; Physics GA 187UL UT WOS:000079806400002 ER PT J AU Giessen, H Butty, J Woggon, U Fluegel, B Mohs, G Hu, YZ Koch, SW Peyghambarian, N AF Giessen, H Butty, J Woggon, U Fluegel, B Mohs, G Hu, YZ Koch, SW Peyghambarian, N TI Ultrafast nonlinear gain dynamics in semiconductor nanocrystals SO PHASE TRANSITIONS LA English DT Article DE semiconductor; nanocrystal; quantum dot; optical amplification; gain dynamics; biexciton to exciton transition; two-electron-hole pair gain model ID CDS QUANTUM DOTS; ZERO-DIMENSIONAL SEMICONDUCTORS; STRONG CONFINEMENT REGIME; OPTICAL-GAIN; DOPED GLASSES; LUMINESCENCE PROPERTIES; TEMPERATURE-DEPENDENCE; INVERTED SEMICONDUCTOR; MODEL SYSTEM; SIZE AB II-VI semiconductor (CdS, CdSe) nanocrystals with an average size of approximately one bulk exciton Bohr radius are embedded in a glass matrix. Due to the quantum confinement effect, they act as a quasi zero-dimensional system (quantum dots). Under strong nano-second and femtosecond optical excitation, these quantum dots exhibit optical amplification (gain). We investigate the ultrashort gain dynamics of the strongly confined CdSe quantum dots by femtosecond pump-probe spectroscopy. From multiple-beam pump-probe measurements, we conclude that the gain mechanism is governed by biexciton to exciton transitions. Femtosecond dephasing measurements reveal a constant scattering rate across the gain region and confirm the two-electron-hole pair gain model. Nano-second pump-probe measurements on CdS quantum dots in sol-gel glasses show optical gain up to room temperature. In all cases, the gain region is broad and stretches below the fundamental absorption of the nanocrystals. The reason is the multitude of transitions involved in the gain formation. No phonon bottleneck did prevent any quick relaxation or any fast scattering that would replenish the spectral holes in the gain region. The relaxation rates are on the order of 10 ps. The luminescence decay time is nonexponential with a 40-100 ps component for the stimulated emission. C1 Univ Arizona, Ctr Opt Sci, Tucson, AZ 85721 USA. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. Univ Karlsruhe, Fachbereich Phys, D-76128 Karlsruhe, Germany. Univ Marburg, Fachbereich Phys, D-35032 Marburg, Germany. Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Tokyo, Dept Appl Phys, Bunkyo Ku, Tokyo 113, Japan. RP Giessen, H (reprint author), Univ Arizona, Ctr Opt Sci, Tucson, AZ 85721 USA. RI Woggon, Ulrike/C-2706-2008 NR 49 TC 5 Z9 5 U1 0 U2 10 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0141-1594 J9 PHASE TRANSIT JI Phase Transit. PY 1999 VL 68 IS 1 BP 59 EP 94 DI 10.1080/01411599908224515 PN B PG 36 WC Crystallography; Physics, Condensed Matter SC Crystallography; Physics GA 187UL UT WOS:000079806400004 ER PT J AU Donnelly, SE Birtcher, RC AF Donnelly, SE Birtcher, RC TI Ion-induced spike effects on metal surfaces SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID TRANSMISSION ELECTRON-MICROSCOPY; DISPLACEMENT CASCADES; COLLISION CASCADES; SIMULATION; DAMAGE AB The effects of single Xe ion impacts on the surfaces of Au, Ag, In and Pb have been studied using in-situ transmission electron microscopy. Individual ion impacts produce surface craters with associated expelled material. The cratering efficiency scales with the density of the irradiated metal. Calculation indicates that, when collision cascades occur near surfaces (within about 5 nm) with energy densities sufficient to cause local melting, craters will occur. Crater formation occurs as a result of the explosive outflow of material from the hot molten core of the cascade. This would appear to indicate that, although the number of atoms in a spike is small and its duration short, it is reasonable to use macroscopic concepts such as vibrational temperature, melting and flow to describe spike effects. C1 Univ Salford, Sci Res Inst, Joule Phys Lab, Salford M5 4WT, Lancs, England. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Donnelly, SE (reprint author), Univ Salford, Sci Res Inst, Joule Phys Lab, Salford M5 4WT, Lancs, England. OI Donnelly, Stephen/0000-0002-9749-5550 NR 19 TC 20 Z9 20 U1 2 U2 5 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD JAN PY 1999 VL 79 IS 1 BP 133 EP 145 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 158WU UT WOS:000078141100010 ER PT J AU Miodownik, M Martin, JW Cerezo, A AF Miodownik, M Martin, JW Cerezo, A TI Mesoscale simulations of particle pinning SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID GRAIN-GROWTH; COMPUTER-SIMULATION; 2ND-PHASE PARTICLES; SIZE DISTRIBUTION; PHASE PARTICLES; MONTE-CARLO; TEMPERATURE; INHIBITION; MODEL AB Despite much debate, there is still little consensus of opinion on the dependence of Zener pinning (the stagnation of grain growth caused by second-phase particles) on the volume fraction. The controversy surrounds attempts to relate the volume fraction of particles to the final pinned grain size. Analytical theories and 3D Monte Carlo simulations are in disagreement and the experimental evidence is inconclusive. In this paper we contribute to the debate by describing mesoscale 3D Monte Carlo simulations of a single boundary moving through an array of particles. It is found that the simulation temperature is a critical variable, and the simulated boundaries possess mobilities independent of driving force only when kT' greater than or equal to 2. This is explained in terms of a ledge mechanism of migration in which ledge repulsion becomes important when kT' < 2. The effect of T' is critical in determining the geometry of the boundary (and hence the pinning force) during particle bypass. When kT' = 0, the expected dimple shape is not observed because the boundary is in a non-equilibrium state (due to ledge repulsion) and this is the origin of the strong pinning observed in the simulations. When kT' greater than or equal to 1, dimples are observed and the pinning force is in good agreement with analytical theory. The implications of this work on the volume fraction dependence of Zener pinning are discussed. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Oxford, Dept Mat, Oxford OX1 3PH, England. RP Miodownik, M (reprint author), Sandia Natl Labs, POB 5800,Mail Stop 1411, Albuquerque, NM 87185 USA. NR 26 TC 39 Z9 39 U1 0 U2 4 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD JAN PY 1999 VL 79 IS 1 BP 203 EP 222 PG 20 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 158WU UT WOS:000078141100015 ER PT J AU Wang, LM Weber, WJ AF Wang, LM Weber, WJ TI Transmission electron microscopy study of ion-beam-induced amorphization of Ca(2)La(8)(SiO(4))(6)O(2) SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID SOLID-STATE AMORPHIZATION; RADIATION-DAMAGE; IRRADIATION; TEMPERATURE; CASCADES; CERAMICS; SILICATE; SURFACE; APATITE; ENERGY AB In-situ transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) were used to study ion-beam-induced amorphization of Ca(2)La(8)(SiO(4))(6)O(2), a silicate ceramic with the apatite structure. In-situ TEM was performed during irradiation with 1 MeVAr(+), 1.5 MeV Kr(+) and 1.5MeV Xe(+) ions over the temperature range from 20 to 773 K to determine the ion dose required for complete amorphization of the crystal (critical amorphization dose D(c)). D(c) increased with increasing irradiation temperature and decreased with increasing ion mass. Samples irradiated with Ar(+), Kr(+) and Xe(+) ions to various doses were used in a detailed HRTEM study of the amorphization process. The residual irradiation damage after low ion doses appeared as nanometre scale amorphous domains. The images of these domains are extremely sensitive to the sample thickness. Small domains of subcascade size were found only at the very thin edge of the sample at lower doses. In thicker regions, amorphous domains appear after higher doses as the result of the subcascade overlap in projection. At higher temperatures. the observed amorphous domains are smaller indicating thermally activated epitaxial recovery at the amorphous-crystalline interface. The amorphous domains are larger in size after irradiation with ions of higher mass. The results are consistent with the D(c)-temperature curves determined by in-sills TEM and suggest an amorphization mechanism through direct subcascade impact or subcascade overlapping. Growth of the surface amorphous layer with increasing ion dose and the effects of electron beam on damage recovery were also noted. In addition; cross-sectional TEM, computer simulation of damage production and digital image processing have also been performed to understand better the plan-view HRTEM observations. C1 Univ Michigan, Dept Nucl Engn & Radiol Sci, Ann Arbor, MI 48109 USA. Pacific NW Lab, Dept Mat Sci, Richland, WA 99352 USA. RP Wang, LM (reprint author), Univ Michigan, Dept Nucl Engn & Radiol Sci, Ann Arbor, MI 48109 USA. RI Weber, William/A-4177-2008 OI Weber, William/0000-0002-9017-7365 NR 38 TC 34 Z9 34 U1 3 U2 18 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD JAN PY 1999 VL 79 IS 1 BP 237 EP 253 PG 17 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 158WU UT WOS:000078141100017 ER PT J AU Joyce, JJ Arko, AJ Sarrao, JL Graham, KS Fisk, Z Riseborough, PS AF Joyce, JJ Arko, AJ Sarrao, JL Graham, KS Fisk, Z Riseborough, PS TI Photoemission from YbInCu4: testing the single impurity model SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article ID TEMPERATURE-DEPENDENCE; ELECTRONIC-STRUCTURE; VALENCE TRANSITION; HEAVY FERMIONS; ANDERSON MODEL; BAND-STRUCTURE; YBIN1-XAGXCU4; SPECTROSCOPY; BEHAVIOR; SYSTEMS AB The electronic properties of single crystal YbInCu4 and YbAgCu4 have been investigated by means of high resolution photoelectron spectroscopy. A first order, isostructural phase transition for YbInCu4 at 42K leads to changes in the Kondo temperature, of more than an order of magnitude. This phase transition and accompanying Kondo temperature change provide the most direct test of the single impurity model to date. The photoemission results are incongruous with the single impurity model predictions for temperature dependence, binding energy and 4f occupancy, encouraging a re-evaluation of the single impurity model applicability. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. High Field Magnet Lab, Tallahassee, FL 32306 USA. Florida State Univ, Tallahassee, FL 32306 USA. Polytech Inst New York, Brooklyn, NY 11201 USA. RP Joyce, JJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Riseborough, Peter/D-4689-2011 NR 19 TC 14 Z9 14 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8637 J9 PHILOS MAG B JI Philos. Mag. B-Phys. Condens. Matter Stat. Mech. Electron. Opt. Magn. Prop. PD JAN PY 1999 VL 79 IS 1 BP 1 EP 8 DI 10.1080/13642819908206776 PG 8 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 158WT UT WOS:000078141000001 ER PT J AU Pinhero, PJ Anderegg, JW Sordelet, DJ Besser, MF Thiel, PA AF Pinhero, PJ Anderegg, JW Sordelet, DJ Besser, MF Thiel, PA TI Surface oxidation of Al-Cu-Fe alloys: a comparison of quasicrystalline and crystalline phases SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article ID QUASI-CRYSTALS; HYDROGEN STORAGE; ADSORPTION; ALUMINUM; AL(111); PHOTOELECTRON; OVERLAYERS; THICKNESS; COATINGS; WATER AB We have used X-ray photoelectron spectroscopy and Auger electron spectroscopy to examine the characteristics of oxide surfaces on a family of Al-Cu-Fe alloys. The alloys studied are compositionally similar but structurally different: two are crystalline and one is quasicrystalline. The samples all are formed by consolidation of powders, resulting in multiple grains with random surface orientations. They are oxidized to saturation in a variety of environments at room temperature. Under the conditions of our experiments, there is no detectable difference in the oxidation characteristics of the three phases. That is, there is no difference in the elemental constituents which oxidize, or in the relative extent of oxygen-induced Al segregation, or in the depth of the oxide formed. Hence, the oxidation chemistry of these alloys is determined by their Al-rich chemical composition, and not by their atomic or electronic bulk structure, under these conditions. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Iowa State Univ, Dept Engn Mech, Ames, IA 50011 USA. RP Pinhero, PJ (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 53 TC 39 Z9 39 U1 1 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8637 J9 PHILOS MAG B JI Philos. Mag. B-Phys. Condens. Matter Stat. Mech. Electron. Opt. Magn. Prop. PD JAN PY 1999 VL 79 IS 1 BP 91 EP 110 DI 10.1080/13642819908206784 PG 20 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 158WT UT WOS:000078141000009 ER PT J AU Ramirez, AP Varma, CM Fisk, Z Smith, JL AF Ramirez, AP Varma, CM Fisk, Z Smith, JL TI Fermi-liquid renormalization in the superconducting state of UBe13 SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article ID DEPENDENT SPECIFIC-HEAT; ORDER AB The specific heat in the mixed phase of superconducting UBe13 is observed to vary as the square of the applied magnetic field. This is shown to imply a Fermi-liquid-type suppression of the exchange enhancement as the superconducting gap opens, similar to that seen in He-3. Consistent with this effect is the observed nonmonotonic temperature dependence of the Maki parameter kappa(2) which is related to the Pauli susceptibility. C1 AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ramirez, AP (reprint author), AT&T Bell Labs, Lucent Technol, 600 Mt Ave, Murray Hill, NJ 07974 USA. NR 18 TC 4 Z9 4 U1 1 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8637 J9 PHILOS MAG B JI Philos. Mag. B-Phys. Condens. Matter Stat. Mech. Electron. Opt. Magn. Prop. PD JAN PY 1999 VL 79 IS 1 BP 111 EP 117 DI 10.1080/13642819908206785 PG 7 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 158WT UT WOS:000078141000010 ER PT J AU Bussmann-Holder, A Bishop, AR AF Bussmann-Holder, A Bishop, AR TI Competing interactions and the isotope effect in colossal magnetoresistance materials SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article ID RESISTIVITY; LAMNO3 AB The experimentally observed large isotope effect on the ferromagnetic transition temperature in doped manganites R(1-x)A(x)MnO(3) is shown to be in agreement with a local Jahn-Teller coupling mechanism. With increasing doping towards the insulating antiferromagnetic state the Mn-O-Mn bond substantially distorts, which is taken into account through intersite (Mn-O) interband electron-phonon interactions. It is shown that there is a competition between the local Jahn Teller and intersite interband couplings; depending on the bond angle distortion, the isotope effect can be suppressed substantially and even reverse sign, consistent with recent experimental results. C1 Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Bussmann-Holder, A (reprint author), Max Planck Inst Festkorperforsch, Heisenbergstr 1, D-70569 Stuttgart, Germany. NR 29 TC 2 Z9 2 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8637 J9 PHILOS MAG B JI Philos. Mag. B-Phys. Condens. Matter Stat. Mech. Electron. Opt. Magn. Prop. PD JAN PY 1999 VL 79 IS 1 BP 119 EP 125 DI 10.1080/13642819908206786 PG 7 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 158WT UT WOS:000078141000011 ER PT J AU Peterson, ES Stewart, FF Stone, ML Harrup, MK Polson, LA Orme, CJ AF Peterson, ES Stewart, FF Stone, ML Harrup, MK Polson, LA Orme, CJ TI Separations using polyphsphazene membranes SO PHOSPHORUS SULFUR AND SILICON AND THE RELATED ELEMENTS LA English DT Article; Proceedings Paper CT XIVth International Conference on Phosphorus Chemistry (XIVth-ICPC) CY JUL 12-17, 1998 CL CINCINNATI, OH SP Cincinnati Local ACS Sect DE membrane separations; polyphosphazenes; water purification; industrial separations; membrane dehydration; ion separations ID PHOSPHAZENE AB Reported in this paper are the separation characteristics and transport mechanisms of membranes formed from poly[bis(phenoxy)phosphazene] based polymers. Separations of industrial interest include water purification, gas separations, liquid state organic-water and organic-organic separations. Many of these environments are chemically aggressive which often leads to the failure of many standard organic-based membrane materials and the polyphosphazenes have been observed to effectively operate in such environments. In this paper, we will develop an argument that shows the value of custom tailoring these membrane materials to fit the specific application of water purification. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Peterson, ES (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. RI Peterson, Eric/B-9127-2017 OI Peterson, Eric/0000-0002-2292-4939 NR 13 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 1042-6507 EI 1563-5325 J9 PHOSPHORUS SULFUR JI Phosphorus Sulfur Silicon Relat. Elem. PY 1999 VL 144 BP 225 EP 229 PG 5 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 249EW UT WOS:000083320800058 ER PT S AU Fleming, JG Lin, SY AF Fleming, JG Lin, SY BE Ho, ST Zhou, Y Chow, WW Arakawa, Y TI 3-D, silicon, infrared, photonic lattices SO PHOTONICS TECHNOLOGY INTO THE 21ST CENTURY: SEMICONDUCTORS, MICROSTRUCTURES, AND NANOSTRUCTURES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Photonics Technology into the 21st Century - Semiconductors, Microstructures, and Nanostructures CY DEC 01-03, 1999 CL SINGAPORE, SINGAPORE SP SPIE, Nanyang Technol Univ, SPIE, Singapore Chapter, Inst Phys, USAF, Asian Off Aerosp Res & Dev, USA, Res Off Far E DE photonic lattice; 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. A variety 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 bandgaps centered from 12 mu down to 1.55 mu, depending on pitch. 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 23 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 0-8194-3501-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3899 BP 258 EP 267 DI 10.1117/12.369406 PG 10 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BP26S UT WOS:000084512600031 ER PT B AU Zweibel, K AF Zweibel, K BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI Baseline evaluation of thin-film amorphous silicon, copper indium diselenide, and cadmium telluride for the 21(st) century SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab AB This paper examines three thin-film PV technologies: amorphous silicon, cadmium telluride, and copper indium selenide. The purpose is to: (1) assess their status and potential; (2) provide an improved set of criteria for comparing these existing thin films against any new PW technological alternatives, and examining the longer-term (c. 2050) potential of thin films to meet cost goals that would be competitive with conventional sources of energy without any added value from the substantial environmental advantages of PV. Among the conclusions are: (1) today's thin films have substantial economic potential, (2) any new approach to PV should be examined against the substantial achievements and potential of today's thin films, (3) the science and technology base of today's thin films needs substantial strengthening, (4) some need for alternative technologies exists, especially as the future PV marketplace expands beyond about 30 GW of annual production. C1 Natl Renewable Energy Lab, Natl Ctr PV, Thin Film PV Partnership, Golden, CO 80401 USA. RP Zweibel, K (reprint author), Natl Renewable Energy Lab, Natl Ctr PV, Thin Film PV Partnership, 1617 Cole Blvd, Golden, CO 80401 USA. NR 5 TC 3 Z9 3 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 3 EP 15 PG 13 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600001 ER PT B AU Tsuo, YS Wang, TH Ciszek, TF AF Tsuo, YS Wang, TH Ciszek, TF BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI Crystalline-silicon solar cells for the 21(st) century SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab ID FILMS AB The worldwide market share for crystalline-silicon solar cells has increased steadily in the last 10 years. In 1998, about 87% of the photovoltaic modules shipped worldwide are based on crystalline silicon. This dominance will likely continue into at least the first few years of the 21(st) century. The long-term growth of crystalline-silicon solar cells will depend on the development olf low-cast polysilicon feedstock, silicon films, and advanced cell and module :manufacturing processes. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Tsuo, YS (reprint author), Natl Renewable Energy Lab, MS-3213,1617 Cole Blvd, Golden, CO 80401 USA. NR 35 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 49 EP 56 PG 8 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600005 ER PT B AU Czanderna, AW Jorgensen, GJ AF Czanderna, AW Jorgensen, GJ BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI Accelerated life testing and service lifetime prediction for PV technologies in the twenty-first century SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab ID DEPENDENCE AB The purposes of this paper are to (1) discuss the necessity for conducting accelerated life testing (ALT) in the early stages of developing new photovoltaic (PV) technologies, (2) elucidate the crucial importance for combining ALT with real-time testing (RTT) in terrestrial environments for promising PV technologies for the 21st century and (3) outline the essential steps for making a service lifetime prediction (SLP) for any PV technology. The specific objectives are to (a) illustrate the essential need for AUT of complete, encapsulated multilayer PV devices, (b) indicate the typical causes of degradation in PV stacks, (c) elucidate the complexity associated with quantifying the durability of the devices, (d) explain the major elements that constitute a generic SLP methodology, (e) show how the introduction of the SLP methodology in the early stages of new device development can reduce the cost of technology development, and (f) outline the procedure for combining the results of ALT and RTT, establishing degradation mechanisms, using sufficient numbers of samples, and applying the SLP methodology to produce a SLP for existing or new PV technologies. C1 Natl Renewable Energy Lab, Natl Ctr Photovolta, Engn & Reliabil Div, Golden, CO 80401 USA. RP Czanderna, AW (reprint author), Natl Renewable Energy Lab, Natl Ctr Photovolta, Engn & Reliabil Div, Golden, CO 80401 USA. NR 28 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 57 EP 67 PG 11 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600006 ER PT B AU Ginley, DS AF Ginley, DS BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI Nanoparticle-derived contacts for photovoltaic cells SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab ID SPRAY DEPOSITION; PRECURSORS; POWDERS AB Contacts are becoming increasingly important as PV devices move to higher efficiency and lower cost. We present an approach to developing contacts using nanoparticle-based precursors. Both elemental, alloy, and compound nanoparticles can be employed for contacts. Ink-based approaches can be used at low temperatures and utilize direct-write techniques such as ink-jet and screen printing. The ability to control the composition of the nanoparticle allows improved control of the contact metallurgy and the potential for thermodynamically stable interfaces. Key is the ability to control the interface between particles and the substrate. We illustrate some of these principals with recent results on Al, Cu and (Hg,Cu)Te. We show for the elemental materials control of the surface can prevent oxide formation and act as glue to control the reactivity of the nanoparticles. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Ginley, DS (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 12 TC 2 Z9 2 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 103 EP 109 PG 7 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600012 ER PT B AU Sopori, B Madjdpour, J Zhang, Y Chen, W AF Sopori, B Madjdpour, J Zhang, Y Chen, W BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI PV Optics: An optical modeling tool for solar cell and module design SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab AB A brief description of the capabilities of PV Optics, a software package for the design and analysis of solar cells and modules, is given. Some specific applications of the software for the design of thick- and thin-film cells are given. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Sopori, B (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 2 TC 5 Z9 5 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 138 EP 144 PG 7 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600016 ER PT B AU Chen, W Sopori, B AF Chen, W Sopori, B BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI A thin silicon solar cell on glass: Cell design and process physics SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab AB We describe a new design for a low-cost, thin-film solar cell on a glass substrate. The structure of the cell is discussed in detail. Several verified steps in the fabrication of this cell are also presented. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Chen, W (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 6 TC 1 Z9 1 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 145 EP 152 PG 8 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600017 ER PT B AU Kurtz, SR Allerman, AA Jones, ED Klem, JF Seager, CH AF Kurtz, SR Allerman, AA Jones, ED Klem, JF Seager, CH BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI Minority carrier lifetimes, defects, and solar cells of InGaAsN, lattice-matched to GaAs SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab ID ALLOY SCATTERING; SEMICONDUCTORS AB Electronic properties, relevant to solar cell applications, are described for InGaAsN, lattice-matched to GaAs. This novel semiconductor displays optical and transport properties which are highly non-ideal and sensitive to growth, doping, and processing conditions. Hole diffusion lengths of 0.6-0.8 mu m can be achieved in annealed, n-type InGaAsN, and internal quantum efficiencies > 70% are obtained for 1.0 eV bandgap cells. Wider bandgap, 1.16 eV cells display high internal quantum efficiencies with significantly larger open-circuit voltages than the1.0 eV cells. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Kurtz, SR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 163 EP 169 PG 7 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600019 ER PT B 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 Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI Photoluminescence investigations of InGaAsN alloys lattice-matched to GaAs SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab ID WAVELENGTH SEMICONDUCTOR-LASERS; QUANTUM-WELL STRUCTURES; BAND-GAP; MAGNETIC-FIELD; GAINNAS; ENERGY AB InGaAsN is a semiconductor alloy system with the property that the inclusion of only 2% nitrogen reduces the bandgap by more than 30%. In this paper, we have measured the conduction-band mass by three different techniques for 2% nitrogen in InGaAsN lattice matched to GaAs. Additionally, we also report pressure dependent measurements of the conduction-band mass between ambient and 40 kbar. Based on our results, we suggest that the observed changes in masses are a result of Gamma-X mixing. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Jones, ED (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 1 Z9 1 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 170 EP 177 PG 8 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600020 ER PT B AU Allerman, AA Kurtz, SR Jones, ED Gee, JM Banks, JC Climent-Font, A AF Allerman, AA Kurtz, SR Jones, ED Gee, JM Banks, JC Climent-Font, A BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI The growth of InGaAsN for high efficiency solar cells by metalorganic chemical vapor deposition SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab AB InGaAsN alloys are a promising material for increasing the efficiency of multi-junction solar cells now used for satellite power systems. However, the growth of these dilute N containing alloys has been challenging with further improvements in material quality needed before the solar cell higher efficiencies are realized. Nitrogen/V ratios exceeding 0.981 resulted in lower N incorporation and poor surface morphologies. The growth rate was found to depend on not only the total group III transport for a fixed N/V ratio but also on the N/V ratio. Carbon tetrachloride and dimethylzinc were effective for p-type doping. Disilane was not an effective n-type dopant while SiC14 did result in n-type material but only a narrow range of electron concentrations (2-5e17cm(-3)) were achieved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Allerman, AA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Climent-Font, Aurelio/G-8449-2016 NR 6 TC 2 Z9 2 U1 0 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 178 EP 184 PG 7 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600021 ER PT B AU Friedman, DJ Geisz, JF Kurtz, SR Norman, AG Yeh, YCM AF Friedman, DJ Geisz, JF Kurtz, SR Norman, AG Yeh, YCM BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI Hydrazine N source for growth of GaInNAs for solar cells SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab ID PERFORMANCE; EPITAXY; GAASN AB We evaluate hydrazine (Hy) as a nitrogen precursor source for the growth of GaNAs and GaInNAs for application in 1-eV solar cells lattice-matched to GaAs, and compare it to the more commonly used dimethylhydrazine (DMHy). The incorporation efficiency of N into the GaNAs alloy is found to be one to two orders of magnitude higher with Hy than with DMHy. This high N incorporation makes convenient the growth of GaNAs at higher growth temperatures, T-g=650 degrees C, and arsine flows, AsH3/III=44, than are generally possible with the use of DMHy. GaInNAs and GaNAs solar cells are grown under these growth conditions and compared to a GaAs cell grown under the same conditions to determine the extent to which the poor minority-carrier properties routinely observed for the N-containing material can be attributed to the growth conditions. Finally, the background carrier concentrations for Hy- and DMHy-grown material are compared, and little difference is found between the two sources. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Friedman, DJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Norman, Andrew/F-1859-2010 OI Norman, Andrew/0000-0001-6368-521X NR 13 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 185 EP 189 PG 5 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600022 ER PT S AU Walukiewicz, W Shan, W Ager, JW Chamberlin, DR Haller, EE Geisz, JF Friedman, DJ Olson, JM Kurtz, SR AF Walukiewicz, W Shan, W Ager, JW Chamberlin, DR Haller, EE Geisz, JF Friedman, DJ Olson, JM Kurtz, SR BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI Nitrogen-induced modification of the electronic structure of group III-N-V alloys SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE Electrochemical Society Series LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab ID GAAS; SEMICONDUCTORS; LUMINESCENCE; GAAS1-XNX; GAP AB Incorporation of nitrogen in conventional III-V compound semiconductors to form III-N-V alloys leads to a splitting of the conduction band into two nonparabolic sub-bands. The splitting can be described in terms of an anticrossing interaction between a narrow band of localized nitrogen states and the extended conduction-band states of the semiconductor matrix. The downward shift of the lower sub-band edge is responsible for the N-induced reduction of the fundamental band-gap energy. The modification of the conduction-band structure profoundly affects the optical and electrical properties of the III-N-V alloys. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 22 TC 52 Z9 52 U1 1 U2 5 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 0275-0171 BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 190 EP 199 PG 10 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600023 ER PT B AU Benner, J Deb, S McConnell, RD AF Benner, J Deb, S McConnell, RD BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI Basic research opportunities in photovoltaics workshop SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Benner, J (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 203 EP 205 PG 3 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600024 ER PT B AU Jones, ED Allerman, AA Friedman, DJ Geisz, JF Klem, JF Kurtz, SR Modine, NR Shan, W Tu, C AF Jones, ED Allerman, AA Friedman, DJ Geisz, JF Klem, JF Kurtz, SR Modine, NR Shan, W Tu, C BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI Next generation thin films for photovoltaics: InGaAsN SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab ID WAVELENGTH SEMICONDUCTOR-LASERS; GAASN ALLOYS; BAND-GAP; OPTICAL-PROPERTIES; GAINNAS; GROWTH; DIMETHYLHYDRAZINE; DEPENDENCE; GAAS1-XNX AB A new semiconductor alloy system, InGaAsN, has been identified as a candidate material for multi-junction solar cells having efficiencies greater than 40%. The introduction of small amounts of nitrogen (similar to 2%) into the InGaAs alloy system greatly reduces the band gap energy, with reductions approaching 0.4 eV for 2% nitrogen content. With the appropriate ratio of indium to nitrogen concentrations, InGaAsN can be lattice matched to GaAs. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Jones, ED (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 33 TC 2 Z9 2 U1 0 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 252 EP 267 PG 16 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600029 ER PT B AU Coutts, TJ Mason, TO Perkins, JD Ginley, DS AF Coutts, TJ Mason, TO Perkins, JD Ginley, DS BE Kapur, VK McConnell, RD Carlson, D Ceasar, GP Rohatgi, A TI Transparent conducting oxides: Status and opportunities in basic research SO PHOTOVOLTAICS FOR THE 21ST CENTURY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 195th Meeting of the Electrochemical-Society CY MAY 02-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Energy Technol Div, US DOE, Off Basic Energy Sci, US DOE, Off Energy Efficieny & Renewable Energy, Natl Renewable Energy Lab ID IN2O3 SINGLE-CRYSTALS; ELECTRICAL-PROPERTIES; FILMS; PERFORMANCE; GAINO3; SYSTEM AB In this paper, we begin by discussing the historical background of transparent conducting oxides and then make some general remarks about their typical properties. This is followed by a short discussion of the desired properties for future applications (particularly photovoltaic devices). These are ambitious objectives but they provide targets for future basic research and development. Although it may be possible to obtain these properties in the laboratory, it is vital to ensure that account is taken of industrial perceptions to the development of the next generation of materials. Hence, we spend some time discussing industrial criteria. Next, we discuss key physical properties that determine the macroscopic physical properties that, in turn, affect the performance of devices. Finally, we select several key topics that ought to be included in future basic research programs. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Coutts, TJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 30 TC 28 Z9 29 U1 0 U2 4 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-233-8 J9 ELEC SOC S PY 1999 VL 99 IS 11 BP 274 EP 288 PG 15 WC Electrochemistry; Energy & Fuels; Engineering, Electrical & Electronic; Optics SC Electrochemistry; Energy & Fuels; Engineering; Optics GA BN99Y UT WOS:000083812600031 ER PT J AU Krueger, BP Scholes, GD Gould, IR Fleming, GR AF Krueger, Brent P. Scholes, Gregory D. Gould, Ian R. Fleming, Graham R. TI Carotenoid mediated B800-B850 coupling in LH2 SO PHYSCHEMCOMM LA English DT Article AB Ab initio calculations of the excited state properties of a portion of the LH(2) complex consisting of a supermolecule of two B850 bacteriochlorophyll (BChl), one B800 BChl, and one rhodopin glucoside carotenoid show significant mixing between the BChl and carotenoid states. Calculation of the B800-B850 coulombic coupling, through the transition density cube method, both with and without the carotenoid reveal that the carotenoid affects an increase in the B800-B850 coupling via an indirect (superexchange) mechanism. This carotenoid-mediated coupling explains a portion of the difference between the B800-B850 energy transfer rate determined experimentally and through traditional (Forster) calculations. C1 [Krueger, Brent P.; Scholes, Gregory D.; Fleming, Graham R.] Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. [Krueger, Brent P.; Scholes, Gregory D.; Fleming, Graham R.] Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. [Gould, Ian R.] Univ London Imperial Coll Sci Technol & Med, Dept Chem, London SW7 2AY, England. RP Krueger, BP (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. FU NSF FX We thank L. Butler and C. Hsu for helpful comments. This work was supported by a grant from the NSF. NR 45 TC 3 Z9 3 U1 0 U2 4 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1460-2733 J9 PHYSCHEMCOMM JI PhysChemComm PY 1999 VL 2 IS 8 PG 7 WC Chemistry, Physical SC Chemistry GA V13IK UT WOS:000207660300001 ER PT J AU Maslov, S Zhang, YC AF Maslov, S Zhang, YC TI Probability distribution of drawdowns in risky investments SO PHYSICA A LA English DT Article AB We study the risk criterion for investments based on the drawdown from the maximal value of the capital in the past. Depending on investor's risk attitude, thus his risk exposure, we find that the distribution of these drawdowns follows a general power law. In particular, if the risk exposure is Kelly-optimal, the exponent of this power law has the borderline value of 2, i.e. the average drawdown is just about to diverge. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Fribourg, Inst Phys Theor, CH-1700 Fribourg, Switzerland. RP Maslov, S (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Maslov, Sergei/C-2397-2009 OI Maslov, Sergei/0000-0002-3701-492X NR 11 TC 13 Z9 13 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD JAN 1 PY 1999 VL 262 IS 1-2 BP 232 EP 241 DI 10.1016/S0378-4371(98)00416-6 PG 10 WC Physics, Multidisciplinary SC Physics GA 155QG UT WOS:000077957400018 ER PT J AU Maple, MB Dilley, NR Gajewski, DA Bauer, ED Freeman, EJ Chau, R Mandrus, D Sales, BC AF Maple, MB Dilley, NR Gajewski, DA Bauer, ED Freeman, EJ Chau, R Mandrus, D Sales, BC TI Strongly correlated electron phenomena in filled skutterudite compounds SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE skutterudite; heavy fermion; strongly correlated electrons ID UFE4P12 AB We report on a search for intermediate valence and heavy fermion behavior in filled skutterudite compounds. The compound YbFe(4)Sb(12) was synthesized and to our knowledge, is the first example of a filled skutterudite of a heavy lanthanide. Transport, magnetic, and thermal measurements on CeFe(4)Sb(12) and YbFe(4)Sb(12) indicate that these materials have a moderately heavy fermion ground state. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif San Diego, Dept Phys 0319, La Jolla, CA 92093 USA. Univ Calif San Diego, Inst Pure & Appl Phys Sci, La Jolla, CA 92093 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Maple, MB (reprint author), Univ Calif San Diego, Dept Phys 0319, 9500 German Dr, La Jolla, CA 92093 USA. EM mbmaple@ucsd.edu RI Bauer, Eric/D-7212-2011; Mandrus, David/H-3090-2014 NR 5 TC 27 Z9 27 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 8 EP 9 DI 10.1016/S0921-4526(98)00629-2 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700003 ER PT J AU Schenck, A Andreica, D Pinkpank, M Gygax, FN Ott, HR Amato, A Heffner, RH MacLaughlin, DE Nieuwenhuys, GJ AF Schenck, A Andreica, D Pinkpank, M Gygax, FN Ott, HR Amato, A Heffner, RH MacLaughlin, DE Nieuwenhuys, GJ TI New mu SR results on the magnetic structure of CeAl2 SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE CeAl2; mu SR; magnetic structure AB Zero field mu SR measurements on a high-quality single crystal of CeAl2 provides, in contrast to earlier mu SR studies, evidence for a single-k incommensurate, sinusoidally modulated AFM-phase below 3.8 K in qualitative agreement with neutron results. Below 1 K we find a drastic change in the mu SR signal which may indicate a further change in the magnetically ordered phase, however, preserving its incommensurately modulated structure, (C) 1999 Elsevier Science B.V. All rights reserved. C1 ETH Zurich, Inst Particle Phys, PSI, CH-5232 Villigen, Switzerland. ETH Honggerberg, Solid State Phys Lab, CH-8093 Zurich, Switzerland. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. Leiden Univ, Kamerlingh Onnes Lab, NL-2300 RA Leiden, Netherlands. RP Schenck, A (reprint author), ETH Zurich, Inst Particle Phys, PSI, CH-5232 Villigen, Switzerland. EM alexander.schenck@psi.ch RI Amato, Alex/H-7674-2013 OI Amato, Alex/0000-0001-9963-7498 NR 4 TC 5 Z9 5 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 14 EP 15 DI 10.1016/S0921-4526(98)01068-0 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700006 ER PT J AU Sarrao, JL AF Sarrao, JL TI Physics of YbInCu4 and related compounds SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE YbInCu4; valence transition; ytterbium compounds ID VALENCE PHASE-TRANSITION; KONDO VOLUME-COLLAPSE; HIGH MAGNETIC-FIELDS; PRESSURE; YBIN1-XAGXCU4; YBXIN1-XCU2; RESISTIVITY; DEPENDENCE; YTTERBIUM; BEHAVIOR AB YbInCu4 exhibits an isostructural valence transition qualitatively similar to that observed at the gamma-alpha transition in elemental Ce. We have prepared single crystals of this compound and related materials, and here we discuss the emerging understanding of the physics of these systems. In particular, the thermodynamics of the valence transition will be discussed, and its response to chemical doping, external magnetic fields, and applied physical pressure will be reviewed. The existence of a single underlying energy scale associated with the valence transition can be inferred from these data. Low carrier concentration seems to play a central role in the physics of the valence transition and this will be demonstrated by discussing related YbXCu4 materials (where X is a semi-metal or late transition metal) that display a wide range of physical properties. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sarrao, JL (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop K 764, Los Alamos, NM 87545 USA. EM sarrao@lanl.gov NR 38 TC 69 Z9 69 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 128 EP 133 DI 10.1016/S0921-4526(98)00620-6 PG 6 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700057 ER PT J AU Robinson, RA Christianson, A Nakotte, H Beyermann, WP Canfield, PC AF Robinson, RA Christianson, A Nakotte, H Beyermann, WP Canfield, PC TI Low-energy excitations, symmetry breaking and specific heat in YbBiPt SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE YbBiPt; crystal-field levels; specific heat ID FERMION COMPOUND YBBIPT; MAGNETISM AB The heavy fermion compound YbBiPt has a very large linear coefficient of specific heat gamma = 8 J mol(-1) K(-2) and this is understood, to first order, in terms of the observed low-energy neutron scattering response. However? at low temperatures, symmetry forbidden splittings at 1 and 2 meV, respectively are observed. These levels give good qualitative agreement with the measured specific heat, but poor quantitative agreement. Indeed, the specific heat drops more rapidly with temperature than can be accounted for assuming a temperature-independent density of states. We also present new low-temperature crystallographic data, which rule out any significant structural distortions. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Robinson, RA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM rrobinson@lanl.gov RI Canfield, Paul/H-2698-2014; christianson, andrew/A-3277-2016 OI christianson, andrew/0000-0003-3369-5884 NR 6 TC 2 Z9 2 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 138 EP 139 DI 10.1016/S0921-4526(98)01135-1 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700060 ER PT J AU Kelley, TM Beyermann, WP Robinson, RK Nakotte, H Canfield, PC Trouw, F AF Kelley, TM Beyermann, WP Robinson, RK Nakotte, H Canfield, PC Trouw, F TI Nonmagnetic crystal-electric-field ground state in the heavy-fermion compound PrInAg2 SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE quadrupolar Kondo interaction; PrInAg2; inelastic neutron scattering; crystal electric field levels AB We have performed inelastic neutron scattering measurements that confirm that the crystal-electric-field split ground state in the heavy-fermion compound PrInAg2 is a nonmagnetic, non-Kramers doublet. This implies that a quadrupolar Kondo interaction is responsible for the enhanced thermodynamic properties observed at low temperatures. We also observe anomalous broadening of the inelastic peaks and suggest two possible causes for this broadening. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. Univ Calif Los Alamos Natl Lab, Lujan Ctr, Los Alamos, NM USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. Iowa State Univ, Ames, IA 50011 USA. Ames Lab, Ames, IA 50011 USA. Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Beyermann, WP (reprint author), Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. EM ward.beyermann@ucr.edu RI Lujan Center, LANL/G-4896-2012; Canfield, Paul/H-2698-2014 NR 4 TC 2 Z9 2 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 163 EP 165 DI 10.1016/S0921-4526(98)01102-8 PG 3 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700072 ER PT J AU Nakotte, H Dilley, NR Torikachvili, MS Bordallo, HN Maple, MB Chang, S Christianson, A Schultz, AJ Majkrzak, CF Shirane, G AF Nakotte, H Dilley, NR Torikachvili, MS Bordallo, HN Maple, MB Chang, S Christianson, A Schultz, AJ Majkrzak, CF Shirane, G TI Structural and magnetic properties of the Kondo insulator UFe4P12 SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE Kondo insulators; magnetic structure; UFe4P12 ID MAGNETORESISTANCE AB Neutron-diffraction results on single crystalline UFe4P12 are reported, The structural parameters of UFe4P12 have been determined at 15 K. Below 3.1 K, we find that there is an additional magnetic contribution on top of nuclear reflections at higher d spacings. An intensity analysis of the magnetic contributions corroborates a ferromagnetic ground state with U moments only. It is argued that this compound forms three magnetic domains with an upper limit of about 0.5 mu(B) (at 2.8 K) for the U moment. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, LANSCE 12, Los Alamos, NM 87545 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Brookhaven Natl Lab, High Flux Beam Reactor, Upton, NY 11973 USA. RP Nakotte, H (reprint author), Univ Calif Los Alamos Natl Lab, LANSCE 12, POB 1663, Los Alamos, NM 87545 USA. EM nakotte_heinz@msmail.lansce.lanl.gov RI Bordallo, Heloisa/I-6836-2012; christianson, andrew/A-3277-2016 OI Bordallo, Heloisa/0000-0003-0750-0553; christianson, andrew/0000-0003-3369-5884 NR 6 TC 11 Z9 11 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 280 EP 282 DI 10.1016/S0921-4526(98)01177-6 PG 3 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700126 ER PT J AU Balatsky, AV Movshovich, R AF Balatsky, AV Movshovich, R TI Marginal stability of d-wave superconductors SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE d(x2-y2) + id(xy) state; second superconducting phase; spontaneous P and T violation; impurity spin ID THERMAL-CONDUCTIVITY AB Thermal conductivity of Bi(2)Sr(2)Ca(Cu(1-x)Ni(x))(2)O(8) high-temperature superconductor display a low-temperature anomaly. It manifests itself as a sharp reduction of the thermal conductivity of the samples at a temperature T*(c) approximate to 200 mK. We interpret this anomaly as an indication of a marginal stability of the d(x2-y2) due to interaction with the spins of magnetic impurities. We suggest that d(x2-y2) + id(xy) state forms below T*(c). (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Theory, Los Alamos, NM 87545 USA. RP Balatsky, AV (reprint author), Univ Calif Los Alamos Natl Lab, Div Theory, B 262, Los Alamos, NM 87545 USA. EM avb@lanl.gov NR 17 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 446 EP 448 DI 10.1016/S0921-4526(98)00750-9 PG 3 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700194 ER PT J AU Campuzano, JC Ding, H Norman, MR Randeria, M AF Campuzano, JC Ding, H Norman, MR Randeria, M TI Destruction of the Fermi surface in underdoped cuprates SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE angle-resolved photoemission; underdoped cuprates; Fermi surface ID ANGLE-RESOLVED PHOTOEMISSION; NORMAL-STATE; SUPERCONDUCTING STATE; GAP; BI2SR2CACU2O8+DELTA; DISPERSION AB We review some of our recent angle-resolved photoemission results on Bi(2)Sr(2)CaCu(2)O(8), as a function of doping. We find that the Fermi surface is progressively destroyed as the temperature is lowered below the pseudogap temperature T* Furthermore, the superconducting gap behaves quite differently at different k-points. All of these results point to a non-mean-held behavior of the superconducting transition. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Univ Illinois, Chicago, IL 60608 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Tata Inst Fundamental Res, Mumbai, India. RP Campuzano, JC (reprint author), Univ Illinois, 845 W Taylor St, Chicago, IL 60608 USA. EM jcc@uic.edu RI Norman, Michael/C-3644-2013; OI Ding, Hong/0000-0003-4422-9248 NR 12 TC 11 Z9 11 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 517 EP 521 DI 10.1016/S0921-4526(98)01014-X PG 5 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700223 ER PT J AU Phillips, NE Emerson, JP Wright, DA Woodfield, BF Gordon, JE Fisher, RA AF Phillips, NE Emerson, JP Wright, DA Woodfield, BF Gordon, JE Fisher, RA TI The specific heat of YBa2Cu3O7-delta: evidence for d-wave pairing SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE YBa2Cu3O7-delta; specific-heat; d-wave pairing ID DENSITY-OF-STATES; SUPERCONDUCTORS; VORTEX; FIELD AB The specific-heat (C) of two polycrystalline samples of YBa2Cu3O7 - delta is reported for 0.8 < 12 K, magnetic fields (H) to 9 T, and 0 less than or equal to delta less than or equal to 0.2. The data confirm a number of effects predicted for d-wave pairing: for H = 0, a T-2 term; for H not equal 0 and H-1/2T less than or similar to 6.5 T-1/2 K, an (HT)-T-1/2 term; for H-1/2T similar to 6.5 T-1/2 K, a crossover to a more complicated H and T dependence; for all H and T, agreement with a proposed scaling relation, C-DOS/((HT)-T-1/2)= F(H-1/2T), where F is an undetermined scaling function and Coos is the electron density of states (DOS) contribution to C. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Lawrence Berkeley Lab, MSD, Berkeley, CA 94720 USA. RP Phillips, NE (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM nephill@cchem.berkeley.edu NR 9 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 522 EP 523 DI 10.1016/S0921-4526(98)00636-X PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700224 ER PT J AU Phillips, NE Fisher, RA Schilling, A Buffeteau, B Hargreaves, TE Marcenat, C Calemczuk, R O'Connor, AS Dennis, KW McCallum, RW AF Phillips, NE Fisher, RA Schilling, A Buffeteau, B Hargreaves, TE Marcenat, C Calemczuk, R O'Connor, AS Dennis, KW McCallum, RW TI The specific heat of (La1.85Sr0.15)CuO4: evidence for d-wave pairing SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE La1.85Sr0.15CuO4; specific heat; d-wave pairing AB The specific heat (C) of two samples of (La1.85ST0.15)CUO4 (LSCO) was measured for 1 < T < 45 K and magnetic fields (H) to 9 T. For both samples the concentrations of paramagnetic centers were relatively low. This facilitated the unambiguous identification of the terms in the electron density of states (DOS) contribution to C (C-DOS) that are expected for d-wave pairing: T-2 for H = 0; (HT)-T-1/2 for H > 0.(C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, MSD, Berkeley, CA 94720 USA. CEA, CENG, Grenoble, France. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Phillips, NE (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM nephill@chem.berkeley.edu NR 3 TC 9 Z9 9 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 546 EP 547 DI 10.1016/S0921-4526(98)00635-8 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700235 ER PT J AU Skanthakumar, S Lynn, JW AF Skanthakumar, S Lynn, JW TI Rare earth magnetic order in RNi2B2C and RNiBC SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE magnetic structure; neutron diffraction; magnetic transitions; borocarbides ID NICKEL BORIDE CARBIDES; CRYSTAL-STRUCTURE; SUPERCONDUCTIVITY; SUSCEPTIBILITY; SUPPRESSION; SCATTERING; YBNI2B2C; HONIBC AB A review of neutron diffraction experiments on the magnetic order in the RNi2B2C and RNiBC (R - rare earth) systems is given. The RNi2B2C materials exhibit a R-ide variety of commensurate and incommensurate magnetic structures for different rare earths, along with superconductivity that is coupled to the magnetism. Simple commensurate antiferromagnetic structures are observed for R = Pr (T-N = 4.0 K), Nd (T-N = 4.8 K), Ho (T-N = 8.5 K) and Dy (T-N = 11 K). In addition, HoNi2B2C exhibits a c-axis spiral and an a-axis modulated incommensurate structure above 5 K, while both structures collapse in favor of the commensurate structure at low T. A transversely polarized spin density wave (SDW) type incommensurate structure is observed for Er (T-N = 6.8 K) and Tm (T-N = 1.5 K), while a longitudinally polarized SDW structure is observed for Tb (T-N = 15 K) No magnetic ordering of any type is detected for Y, Ce and Yb. HoNiBC is an antiferromagnet (T-N = 9.8 K), ErNiBC is ferromagnetic (T-C = 4.6 K), while TbNiBC and DyNiBC exhibit both ferromagnetic and antiferromagnetic ordering at 17 K and similar to 12 K, respectively. Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Skanthakumar, S (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. EM skantha@anl.gov NR 24 TC 22 Z9 24 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 576 EP 581 DI 10.1016/S0921-4526(98)00730-3 PG 6 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700248 ER PT J AU Eskildsen, MR Harada, K Gammel, PL Andersen, NH Ernst, G Ramirez, AP Bishop, DJ Mortensen, K Canfield, PC AF Eskildsen, MR Harada, K Gammel, PL Andersen, NH Ernst, G Ramirez, AP Bishop, DJ Mortensen, K Canfield, PC TI Hysteresis in the field-induced magnetic structure in TmNi2B2C SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE magnetism; superconductivity; borocarbides ID FLUX-LINE-LATTICE; CRYSTAL-STRUCTURE; SUPERCONDUCTIVITY; ERNI2B2C; LUNI2B2C AB Using small-angle neutron scattering we have studied the flux line lattice and the magnetic structure in TmNi2B2C. With an applied field parallel to the crystalline c-axis several magnetic and flux line lattice symmetry transitions have been reported. The subject of this paper is the held-induced magnetic structure and how it is influenced by the flux line lattice symmetry. We find that the domain splitting of the field-induced magnetic structure is hysteretic, and appears to be determined by the history of the flux line lattice symmetry. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Riso Natl Lab, Condensed Matter Phys & Chem Dept, DK-4000 Roskilde, Denmark. Hitachi Ltd, Hatoyama, Saitama 35003, Japan. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Eskildsen, MR (reprint author), Riso Natl Lab, Condensed Matter Phys & Chem Dept, POB 49, DK-4000 Roskilde, Denmark. EM morten.eskildsen@risoe.dk RI Mortensen, Kell/A-5066-2009; Eskildsen, Morten/E-7779-2011; Andersen, Niels/A-3872-2012; Canfield, Paul/H-2698-2014 OI Mortensen, Kell/0000-0002-8998-9390; NR 9 TC 4 Z9 4 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 582 EP 583 DI 10.1016/S0921-4526(98)00732-7 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700249 ER PT J AU Beyermann, WP Lacerda, AH Canfield, PC AF Beyermann, WP Lacerda, AH Canfield, PC TI Field-dependent response of the heavy Fermi-liquid ground state in YbNi2B2C SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE borocarbide; Yb-based heavy fermion; field-dependent specific heat ID SUPERCONDUCTIVITY; BEHAVIOR AB We measured the specific heat of YbNi2B2C in applied fields up to 18 T. As the magnetic field is increased, the peak in the specific heat associated with the Kondo anomaly moved to higher temperatures. This behavior is consistent with theoretical predictions, and a semi-quantitative description of this continuous evolution of the specific heat is presented. Previously, the magnetoresistance of this system was measured, and a comparison is made between field-dependent response of the thermodynamic and transport properties of YbNi2B2C. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. Univ Calif Los Alamos Natl Lab, NHMFL, Los Alamos, NM USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Beyermann, WP (reprint author), Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. EM ward.beyermann@ucr.edu RI Canfield, Paul/H-2698-2014 NR 11 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 584 EP 585 DI 10.1016/S0921-4526(98)01140-5 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700250 ER PT J AU Nagarajan, R Alleno, E Blundell, SJ Mazumdar, C Cooke, DW Cottrell, SP Cox, SFJ Godart, C Gupta, LC Hossain, Z Hults, WL Jestadt, T Peterson, EJ Pratt, FL Smith, JHL AF Nagarajan, R Alleno, E Blundell, SJ Mazumdar, C Cooke, DW Cottrell, SP Cox, SFJ Godart, C Gupta, LC Hossain, Z Hults, WL Jestadt, T Peterson, EJ Pratt, FL Smith, JHL TI Nature of the spin state in TmNi2B2C SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE Quaternary borocarbides; coexistence of superconductivity and magnetism; mu-SR; TmNi2B2C ID SUPERCONDUCTIVITY; SYSTEM AB We had observed earlier that in the quaternary borocarbide magnetic superconductor TmNi2B2C (T-c = 11K, T-N = 1.5 K) quasistatic magnetic correlations persist well above TN (up to similar to 20 K), which is rather unusual. To further probe the nature of its spin state, we used magnetically oriented powder samples of TmNi2B2C and the mu-SR technique. We observe that the quasistatic internal held has a well defined direction. The spontaneous muon precession signal has three times the amplitude when the c-axis alignment is perpendicular to the initial muon beam polarization than when parallel. The transverse configuration enhances the oscillatory signal. This has enabled us to show that the quasistatic magnetic correlations persist even up to 50 K. Furthermore, we find a peak around 7 G in the field dependence of the longitudinal relaxation, which we attribute to the presence of a level crossing resonance arising from quadrupole levels of the boron nuclei. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Tata Inst Fundamental Res, Solid State Phys Grp, Bombay 400005, Maharashtra, India. CNRS, UPR 209, Grp Labs Thiais, F-94320 Thiais, France. Univ Oxford, Clarendon Lab, Oxford OX1 3PU, England. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Rutherford Appleton Lab, ISIS, Didcot OX11 0QX, Oxon, England. RP Nagarajan, R (reprint author), Tata Inst Fundamental Res, Solid State Phys Grp, Homi Bhabha Rd, Bombay 400005, Maharashtra, India. EM nag@tifr.res.in NR 12 TC 7 Z9 7 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 588 EP 589 DI 10.1016/S0921-4526(98)01031-X PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700252 ER PT J AU Sierks, C Loewenhaupt, M Tils, P Freudenberger, J Muller, KH Loong, CK Schober, H AF Sierks, C Loewenhaupt, M Tils, P Freudenberger, J Muller, KH Loong, CK Schober, H TI Magnetic excitations in the Kondo-lattice (YbNi2B2C)-B-11 SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE inelastic neutron scattering; Kondo-lattice; YbNi2B2C ID YBNI2B2C AB We investigated a powder sample of (YbNi2B2C)-B-11 by means of inelastic neutron scattering at different temperatures between 1.6 and 250 K with different incident neutron energies. We determined the Kondo temperature to 3.8 K and found very broad crystal field excitations. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Tech Univ Dresden, Inst Angew Phys, IAPD, D-01062 Dresden, Germany. IFW Dresden, D-01171 Dresden, Germany. Argonne Natl Lab, IPNS, Argonne, IL 60439 USA. Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. RP Sierks, C (reprint author), Tech Univ Dresden, Inst Angew Phys, IAPD, D-01062 Dresden, Germany. OI Freudenberger, Jens/0000-0002-3432-886X NR 6 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 592 EP 593 DI 10.1016/S0921-4526(98)00625-5 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700254 ER PT J AU Mun, MO Cho, BK Lee, SI Canfield, PC Johnston, DC AF Mun, MO Cho, BK Lee, SI Canfield, PC Johnston, DC TI The mixed state properties of superconducting YNi2B2C SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE intermetallic; vortex; mixed state; fluctuation ID FLUCTUATION; DISORDER; LATTICE; GLASS AB YNi2B2C intermetallic superconductor has the fluctuation magnetoconductance showing the 3D scaling behavior. In the mixed state, due to this fluctuation effect, the vortices form a solid phase at low temperature and make a liquid phase near T-c similar to high-T-c materials. Moreover, the Vortex solid becomes a lattice at low fields and the vortex glass transition is found for high fields of H greater than or equal to 2 T while the liquid phase is narrow. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Pohang Univ Sci & Technol, Dept Phys, Natl Creat Res Initiat Ctr Superconduct, Pohang 790784, South Korea. Ewha Womans Univ, Dept Phys, Seoul 120750, South Korea. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. RP Lee, SI (reprint author), Pohang Univ Sci & Technol, Dept Phys, Natl Creat Res Initiat Ctr Superconduct, Pohang 790784, South Korea. EM silee@vision.postech.ac.kr RI Canfield, Paul/H-2698-2014 NR 9 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 599 EP 600 DI 10.1016/S0921-4526(98)00997-1 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700257 ER PT J AU Oomi, G Matsuda, N Honda, F Kagayama, T Honda, K Cho, BK Canfield, PC AF Oomi, G Matsuda, N Honda, F Kagayama, T Honda, K Cho, BK Canfield, PC TI Effect of pressure on the critical temperature and magnetic field of TmNi2B2C SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE high pressure; borocarbide; superconductivity; antiferromagnetism ID SUPERCONDUCTIVITY; HO; ER; TM AB The electrical resistivity of single crystalline TmNi2B2C has been measured at high pressures up to 2 GPa and magnetic fields up to 5 T. It is found that the superconducting transition temperature T-c and the upper critical field H-c2 decrease with increasing pressure, partial derivative T-c/partial derivative P = - 0.50 K/GPa and partial derivative H-c2/partial derivative P = - 0.38 T/GPa. The present results are compared with those of other borocarbides and discussed by taking into account the interplay between the superconductivity and the antiferromagnetism. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Kumamoto Univ, Dept Mech Engn & Mat Sci, Kumamoto 8608555, Japan. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Oomi, G (reprint author), Kumamoto Univ, Dept Mech Engn & Mat Sci, Kumamoto 8608555, Japan. EM oomi@gpo.kumamoto-u.ac.jp RI Canfield, Paul/H-2698-2014; HONDA, Fuminori/D-5578-2015 OI HONDA, Fuminori/0000-0002-9485-7384 NR 12 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 601 EP 603 DI 10.1016/S0921-4526(98)01109-0 PG 3 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700258 ER PT J AU Feller, JR Dasgupta, D Zhang, N Hinks, DG Ketterson, JB Sarma, BK AF Feller, JR Dasgupta, D Zhang, N Hinks, DG Ketterson, JB Sarma, BK TI Velocity dispersion at the metamagnetic transition in UPt3 SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE UPt3; metamagnetism; velocity dispersion; high magnetic fields AB The longitudinal ultrasonic attenuation and velocity were measured on a single crystal of UPt3 in magnetic fields up to 27 T. Earlier measurements had reported metamagnetic behavior in the vicinity of 20 T, where a pronounced velocity dip (softening of the lattice) is seen. Simultaneous measurements at three frequencies during the same run were possible. A small dispersion in the velocity is seen at the metamagnetic transition. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Wisconsin, Dept Phys, Milwaukee, WI 53201 USA. Northwestern Univ, Dept Phys, Evanston, IL 60208 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Sarma, BK (reprint author), Univ Wisconsin, Dept Phys, POB 413, Milwaukee, WI 53201 USA. EM bksarma@csd.uwm.edu RI Ketterson, John/B-7234-2009 NR 5 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 656 EP 657 DI 10.1016/S0921-4526(98)01057-6 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700280 ER PT J AU Kang, JS Inada, Y Onuki, Y Olson, CG Kwon, SK Min, BI AF Kang, JS Inada, Y Onuki, Y Olson, CG Kwon, SK Min, BI TI Photoemission lineshape of CeNiSn near the Fermi level SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE photoemission; CeNiSn; pseudo-gap ID ENERGY-GAP AB The high-resolution photoemission spectroscopy study of single crystalline CeNiSn indicates a finite density of states at E(F), implying a semi-metallic ground state. This finding is supported by the lineshape analysis using the DOS models. The Ce 4f spectrum exhibits three peak structures, in which the peak near-E(F) is found to reflect a substantially large Ce 4f-Sn sp hybridization. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Korea Univ, Dept Phys, Puchon 422743, South Korea. Osaka Univ, Grad Sch Sci, Toyonaka, Osaka 560, Japan. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Pohang Univ Sci & Technol, Dept Phys, Pohang 790784, South Korea. RP Kang, JS (reprint author), Korea Univ, Dept Phys, Puchon 422743, South Korea. EM jskang@www.cuk.ac.kr NR 11 TC 1 Z9 1 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 1116 EP 1117 DI 10.1016/S0921-4526(98)00821-7 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700481 ER PT J AU Denlinger, JD Allen, JW Yang, SH Oh, SJ Cho, EJ Ellis, WP Gajewski, DA Chau, R Maple, MB AF Denlinger, JD Allen, JW Yang, SH Oh, SJ Cho, EJ Ellis, WP Gajewski, DA Chau, R Maple, MB TI Fermi-energy 5f spectral weight growth in Y1-xUxPd3 SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE uranium; 5f; resonant photoemission; Anderson impurity model ID KONDO AB High-resolution small-spot resonant photoemission measurements of the Y1-xUxPd3 ahoy system have revealed the variation in the U 5f lineshape down to 1% uranium dilution. Qualitatively, the spectrum consists of a peak below E-F and a second peak impinging on E-F As x decreases from 1 to 0, the first peak moves toward E-F due to a process known as Fermi-level tuning. In addition, the relative intensity of the E-F peak is observed to grow in accordance with the onset of Kondo-like transport properties. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. Seoul Natl Univ, Dept Phys, Seoul 151742, South Korea. Chonnam Natl Univ, Kwangju 501757, South Korea. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Denlinger, JD (reprint author), Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM jddenlinger@lbl.gov NR 5 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 1130 EP 1131 DI 10.1016/S0921-4526(98)00802-3 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700488 ER PT J AU Cox, LE Peek, JM Allen, JW AF Cox, LE Peek, JM Allen, JW TI Pu 4f XPS spectra analyzed in the Anderson impurity model SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT International Conference on Strongly Correlated Electron Systems (SCES 98) CY JUL 15-18, 1998 CL PARIS, FRANCE SP CNRS, Minist Educ Natl Rech Technol, CEA, Minist Affaires Etrangeres, DGA, Univ Paris-Sud DE Pu; 4f; XPS; Anderson model ID ELECTRONIC-STRUCTURE AB X-ray photoemission spectra of the alpha, beta, gamma, and delta phases of Pu have been analyzed using the Gunnarsson-Schonhammer implementation of the Anderson impurity model. Changes in the relative spectral weights of the two features representing mixed f(5) and f(6) final states are in reasonable agreement with the model's predictions. The Coulomb terms, U(ff) and Uf(fc), are quite consistent with those derived from atomic and LDA calculations. Multiplet structure, which agrees with atomic calculations for 4f(13)5f(5), strongly suggests 5f localization in the final state. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. RP Cox, LE (reprint author), Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. EM lcox@lanl.gov NR 6 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD JAN PY 1999 VL 259-61 BP 1147 EP 1148 DI 10.1016/S0921-4526(98)00618-8 PG 2 WC Physics, Condensed Matter SC Physics GA 179FR UT WOS:000079315700496 ER PT J AU Smith, RA Tisch, JWG Ditmire, T Springate, E Hay, N Mason, MB Gumbrell, ET Comley, AJ Mountford, LC Marangos, JP Hutchinson, MHR AF Smith, RA Tisch, JWG Ditmire, T Springate, E Hay, N Mason, MB Gumbrell, ET Comley, AJ Mountford, LC Marangos, JP Hutchinson, MHR TI The generation of high energy ions by photo-induced dissociation of atomic clusters SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID INTENSE LASER-PULSES; XENON CLUSTERS; ARGON CLUSTERS; XE CLUSTERS; GAS-JET; PLASMA; SPECTROSCOPY; IRRADIATION; TEMPERATURE; IONIZATION AB The interaction of an intense laser pulse of sub-picosecond duration with an atomic cluster larger than a few hundred atoms can be extremely energetic. The high local density within the cluster together with a dynamic dielectric resonance in the expanding cluster microplasma greatly enhance coupling of the laser to both ion and electron kinetic energies. In contrast to the few tens of eV temperatures typically produced in laser irradiation of monatomic gases, cluster targets can produce electron energy distributions in the few keV range, mean ion temperatures of 10-50 keV and peak ion kinetic energies up to 1 MeV. In addition, charge states up to 40(+) can be produced with quite modest laser intensities (approximate to 10(16) Wcm(-2)). Cluster targets are also surprisingly efficient (>90%) at absorbing intense laser light, and thus provide a new route to producing very high energy density, highly ionized laboratory plasmas of interest to a broad range of disciplines. Here we review recent experimental results and outline some areas of current research in this new field. C1 Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Smith, RA (reprint author), Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Prince Consort Rd, London SW7 2BZ, England. NR 28 TC 16 Z9 15 U1 1 U2 2 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80A BP 35 EP 39 DI 10.1238/Physica.Topical.080a00035 PG 5 WC Physics, Multidisciplinary SC Physics GA 227RG UT WOS:000082093000004 ER PT J AU Kaufman, AN AF Kaufman, AN TI A methodology for wave conversion SO PHYSICA SCRIPTA LA English DT Article ID LINEAR-MODE-CONVERSION; GEOMETRIC OPTICS AB The conversion of energy from one wave type to another is spatially localized by nonuniformity of the medium. This process can be analyzed in terms of the local linear interaction of wave fields on rays that propagate in phase space. The methodology presented results in the replacement of partial differential equations for the wave fields by ordinary differential equations for rays, wave amplitudes, and wave phases. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Kaufman, AN (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 15 TC 0 Z9 0 U1 0 U2 2 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T82 BP 69 EP 70 DI 10.1238/Physica.Topical.082a00069 PG 2 WC Physics, Multidisciplinary SC Physics GA 236HE UT WOS:000082593500018 ER PT J AU Morozov, VA Meyer, FW Roncin, P AF Morozov, VA Meyer, FW Roncin, P TI Multi-coincidence studies as a technique for the investigation of ion-surface interaction SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID HIGHLY-CHARGED IONS; SLOW; SCATTERING AB Using a recently developed multi detector, a large variety of multi-coincidence studies for ion-surface interaction becomes possible. In particular this includes simultaneous measurements of projectile energy losses and angular scattering patterns in combination with statistics, angular and energy distributions of secondary electrons emitted. Results are presented for grazing scattering of protons and Oq+ (q = 2,3,5,6; E = 10 keV) ions from LiF single crystal which demonstrate the potential of the technique for investigating ion-surface interaction and deliver interesting new information on projectile energy losses and secondary electron emission in correlation with scattering angle. As a future development a possible combination of this technique with the voltage labeling method for studying backscattered projectiles will be discussed. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Paris Sud, CNRS URA 0281, Collis Atom & Mol Lab, F-91405 Orsay, France. Russian Acad Sci, Inst Problems Mech, Moscow 117526, Russia. RP Morozov, VA (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. OI roncin, philippe/0000-0002-7407-9474 NR 8 TC 3 Z9 5 U1 0 U2 1 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80A BP 69 EP 72 DI 10.1238/Physica.Topical.080a00069 PG 4 WC Physics, Multidisciplinary SC Physics GA 227RG UT WOS:000082093000011 ER PT J AU Schenkel, T Hamza, AV Barnes, AV Newman, MW Machicoane, G Niedermayer, T Hattass, M McDonald, JW Schneider, DH Wu, KJ Odom, RW AF Schenkel, T Hamza, AV Barnes, AV Newman, MW Machicoane, G Niedermayer, T Hattass, M McDonald, JW Schneider, DH Wu, KJ Odom, RW TI Surface analysis by highly charged ion based secondary ion mass spectrometry SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID PARTICLES AB Electronic sputtering in the interaction of slow (v < 10(6) m/s), highly charged ions (e.g., AU(69+)) With Solid surfaces increases secondary ion yields by over two orders of magnitude compared to sputtering with singly charged ions. We discuss advantages of highly charged ions for analysis of semiconductors and biomolecular solids in a time-of-flight secondary ion mass spectrometry scheme. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Charles Evans & Associates, Redwood City, CA 94063 USA. RP Schenkel, T (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 15 TC 14 Z9 15 U1 0 U2 3 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80A BP 73 EP 75 DI 10.1238/Physica.Topical.080a00073 PG 3 WC Physics, Multidisciplinary SC Physics GA 227RG UT WOS:000082093000012 ER PT J AU Heen, LT Hjalmarson, HP AF Heen, LT Hjalmarson, HP TI Recombination processes in type I and type II Sb-based laser structures SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT 18th Nordic Semiconductor Meeting CY JUN 07-10, 1998 CL LINKOPING, SWEDEN SP Spectra Precision, Gamma Optronics, Epigress, Hamamatsu, Scandnordax, GammaData, Wafertech Sancdinavia, Crysis ID THRESHOLD CURRENT-DENSITY; MIDWAVE-INFRARED-LASERS; MU-M; THEORETICAL PERFORMANCE; DIODE-LASERS; DETECTORS; POWER; SUPERLATTICES AB Radiative and non-radiative recombination processes in Sb-based laser structures are calculated and discussed with a focus on the differences between type I and type II laser structures. Anger recombination, optical gain, and intervalence band absorption are computed as a function of temperature for ideal laser threshold conditions. These quantities as well as laser threshold currents are discussed for each type of structure. The calculations show that the type I structure is dominated by radiative recombination at low temperatures and by electron Auger processes at high temperatures, and it has the lowest threshold current of the two laser structures studied. The type II structure has similar behavior except it is dominated by hole Auger processes at high temperatures. Finally, these recombination rates are correlated with qualitative features in the bandstructures. C1 Norwegian Univ Sci & Technol, Dept Phys Elect, N-7034 Trondheim, Norway. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Heen, LT (reprint author), Ctr Technol, N-2007 Kjeller, Norway. NR 26 TC 1 Z9 1 U1 1 U2 3 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T79 BP 106 EP 110 DI 10.1238/Physica.Topical.079a00106 PG 5 WC Physics, Multidisciplinary SC Physics GA 188YW UT WOS:000079877800024 ER PT J AU Liedahl, DA AF Liedahl, DA TI Spectroscopy with the new generation of X-ray observatories SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT 6th International Colloquium on Atomic Spect and Oscillator Strengths (ASOS 6) CY AUG 09-13, 1998 CL UNIV VICTORIA, VICTORIA, CANADA SP Herzberg Inst Astrophys, Natl Res Council Canada, Natl Inst Stand & Technol, Univ Victoria, Dept Phys & Astron HO UNIV VICTORIA ID TRANSMISSION GRATING SPECTROMETER; DIELECTRONIC SATELLITE SPECTRA; HIGH-RESOLUTION MEASUREMENTS; ELECTRON-IMPACT EXCITATION; YOUNG SUPERNOVA-REMNANTS; INNER-SHELL TRANSITIONS; ACTIVE GALACTIC NUCLEI; CHARGED HELIUM-LIKE; LITHIUM-LIKE IONS; LINE EMISSION AB The reliable extraction of physical information from astrophysical X-ray spectra depends upon the accuracy and completeness of plasma emission codes, which have become standard tools for the analysis of spectroscopic data from cosmic X-ray sources. These codes are designed to process atomic data and synthesize model spectra for the cosmically abundant elements over a wide range of temperatures and densities and often need to accommodate the presence of an ionizing radiation field. The upcoming launches of AXAF, XMM and Astro-E will usher in a new era of astrophysical X-ray spectroscopy, characterized by large collecting area, broad bandpass and order-of-magnitude improvements in spectral resolving power. The highly detailed spectra to be acquired with the new satellite observatories will present major challenges for analysts, plasma spectroscopists and atomic physicists. In fact, results from the ASCA and EUVE missions have already exposed problems in plasma codes, attributable to inadequacies in the incorporated atomic data. Revisions of the atomic database are being pursued along three avenues: atomic modeling, laboratory experiments and astrophysical observations. I will draw upon recent results in X-ray astronomy to establish the framework in which to discuss some of the problems faced by atomic modelers in the push to improve plasma emission codes. C1 Lawrence Livermore Natl Lab, Dept Phys, Livermore, CA 94550 USA. RP Liedahl, DA (reprint author), Lawrence Livermore Natl Lab, Dept Phys, Livermore, CA 94550 USA. NR 154 TC 2 Z9 2 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0031-8949 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T83 BP 110 EP 124 DI 10.1238/Physica.Topical.083a00110 PG 15 WC Physics, Multidisciplinary SC Physics GA 262UM UT WOS:000084084900015 ER PT J AU Beiersdorfer, P Schweikhard, L Olson, R Brown, GV Utter, SB Lopez-Urrutia, JRC Widmann, K AF Beiersdorfer, P Schweikhard, L Olson, R Brown, GV Utter, SB Lopez-Urrutia, JRC Widmann, K TI X-ray measurements of charge transfer reactions involving cold, very highly charged ions SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID MAGNETIC TRAPPING MODE; ELECTRON-CAPTURE; SPECTROSCOPY; COLLISIONS; EMISSION AB The magnetic trapping mode of the Livermore high-energy Electron Beam Ion Trap is exploited to study charge transfer reactions between cold (few eV/amu) highly charged ions and gases. By selectively puffing neutral gases and monitoring the Xray emission, state-selective measurements of the charge transfer reaction channels are possible. The observed K-shell X-ray spectra show prominent emission from high-n levels decaying to the n = 1 ground level, which is enabled by electron capture into states with low orbital angular momentum. A comparison with modeling calculations, therefore, allows a determination of the range of principal and angular momentum quantum numbers involved in the reaction. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94550 USA. Univ Mainz, Inst Phys, D-55099 Mainz, Germany. Univ Missouri, Dept Phys, Rolla, MO 65401 USA. RP Beiersdorfer, P (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94550 USA. RI Crespo Lopez-Urrutia, Jose R./F-7069-2011 OI Crespo Lopez-Urrutia, Jose R./0000-0002-2937-8037 NR 11 TC 15 Z9 16 U1 0 U2 2 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80A BP 121 EP 123 DI 10.1238/Physica.Topical.080a00121 PG 3 WC Physics, Multidisciplinary SC Physics GA 227RG UT WOS:000082093000024 ER PT J AU Ionescu, DC Belkacem, A AF Ionescu, DC Belkacem, A TI Relativistic collisions of highly-charged ions SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID POSITRON PAIR PRODUCTION; K-SHELL IONIZATION; ATOMIC-COLLISIONS; ELECTRON-CAPTURE; NONPERTURBATIVE CHARACTER; HEAVY-IONS; H-LIKE; ENERGY; EXCITATION; CREATION AB The physics of elementary atomic processes in relativistic collisions between highly-charged ions and atoms or other ions is briefly discussed, and some recent theoretical and experimental results in this field are summarized. They include excitation, capture, ionization, and electron-positron pair creation. The numerical solution of the two-center Dirac equation in momentum space is shown to be a powerful nonperturbative method for describing atomic processes in relativistic collisions involving heavy and highly-charged ions. By propagating negative-energy wave packets in time the evolution of the QED vacuum around heavy ions in relativistic motion is investigated Recent results obtained from numerical calculations using massively parallel processing on the Cray-T3E supercomputer of the National Energy Research Scientific Computer Center (NERSC) at Berkeley National Laboratory are presented. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ionescu, DC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Mail Stop 71-259,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 32 TC 9 Z9 9 U1 1 U2 1 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80A BP 128 EP 132 DI 10.1238/Physica.Topical.080a00128 PG 5 WC Physics, Multidisciplinary SC Physics GA 227RG UT WOS:000082093000026 ER PT J AU Bertschinger, G Biel, W Herzog, O Weinheimer, J Kunze, HJ Bitter, M AF Bertschinger, G Biel, W Herzog, O Weinheimer, J Kunze, HJ Bitter, M CA TEXTOR-94 Team TI X-ray spectroscopy at the TEXTOR-94 tokamak SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT 6th International Colloquium on Atomic Spect and Oscillator Strengths (ASOS 6) CY AUG 09-13, 1998 CL UNIV VICTORIA, VICTORIA, CANADA SP Herzberg Inst Astrophys, Natl Res Council Canada, Natl Inst Stand & Technol, Univ Victoria, Dept Phys & Astron HO UNIV VICTORIA ID DIELECTRONIC SATELLITE SPECTRA; HELIUM-LIKE IONS; EXCITATION RATES; PLASMAS; LINES; POLARIZATION; TEMPERATURE; IMPURITIES; ROTATION AB Spectra of the 1s-2p resonance line of helium-like argon, Ar XVII, and the associated satellites in the narrow wavelength range from 3.9494 Angstrom to 3.9944 tf have been observed at TEXTOR-94 with two high-resolution X-ray crystal spectrometers at Bragg angles near 54 degrees. Together, these instruments can be used as an X-ray polarimeter. The instruments are very sensitive to small amounts of argon; thus, a count rate of 4x10(5) photons/s, which corresponds to the maximum count rate capability of the presently used detectors, can be obtained for argon densities of less than 10(-3) times the electron density, if the central electron temperature is about 1 keV. Up to 8192 spectra per discharge can be recorded allowing for the investigation of fast events during MHD activities. The instruments have been used to study the electron and ion behavior during internal sawtooth oscillations, which affect the confinement properties in the core of the plasma. The X-ray polarimeter at TEXTOR-94 is a unique diagnostic tool for the measurement of non-Maxwellian electron-velocity distributions, which can be produced in tokamak discharges in the presence of electric fields. First polarization measurements were performed during the flat-top phase in discharges with both pure ohmic heating and additional neutral-beam heating. These measurements showed that inhomogeneities in the emissivity profile can produce effects which look like polarization effects. No polarization was found when these source inhomogeneities were taken into account. The polarimeter is presently upgraded by an imaging X-ray crystal to facilitate polarization measurements. This will be important for the upcoming experiments with electron cyclotron heating at TEXTOR-94. C1 Forschungszentrum Julich, Inst Plasma Phys, Julich, Germany. Ruhr Univ Bochum, Dept Expt Phys 5, Bochum, Germany. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Bertschinger, G (reprint author), Forschungszentrum Julich, Inst Plasma Phys, Julich, Germany. NR 46 TC 28 Z9 28 U1 0 U2 2 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T83 BP 132 EP 141 DI 10.1238/Physica.Topical.083a00132 PG 10 WC Physics, Multidisciplinary SC Physics GA 262UM UT WOS:000084084900018 ER PT J AU Dunford, RW Kanter, EP Schaffer, HW Mokler, PH Berry, HG Livingston, AE Cheng, S Curtis, LJ AF Dunford, RW Kanter, EP Schaffer, HW Mokler, PH Berry, HG Livingston, AE Cheng, S Curtis, LJ TI Higher order photon transitions in H-like and He-like ions SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID ELECTRIC-FIELD; FORBIDDEN TRANSITIONS; 2-PHOTON DECAY; HYDROGENLIKE; INTERFERENCE; STATE AB Higher order photon transitions such as M1, M2 and two-photon decay are conveniently studied using highly-charged few electron ions. Here we discuss two examples from recent experiments which were done using the ATLAS facility at Argonne National Laboratory. The first is a test of Relativistic Quantum Mechanics involving a precision measurement of the spectral shape of the two-photon decay of the 1s2s(1) S(0) state in He-like nickel and the second is a test of the theory of damping in quantum mechanics involving observation of EI - M1 interference in the electric field quenching of metastable H-like ions. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Gesell Schwerionenforsch mbH, D-64291 Darmstadt, Germany. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Toledo, Dept Phys & Astron, Toledo, OH 43606 USA. RP Dunford, RW (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 20 TC 3 Z9 3 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0031-8949 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80A BP 143 EP 144 DI 10.1238/Physica.Topical.080a00143 PG 2 WC Physics, Multidisciplinary SC Physics GA 227RG UT WOS:000082093000029 ER PT J AU Church, DA Schneider, D Steiger, J Beck, BR Holder, JP Weinberg, G Gruber, L Moehs, DP McDonald, J AF Church, DA Schneider, D Steiger, J Beck, BR Holder, JP Weinberg, G Gruber, L Moehs, DP McDonald, J TI Highly-charged ions in traps - Progress and opportunities SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID CROSS-SECTIONS; ELECTRON-CAPTURE; PRECISION-MEASUREMENT; LIFETIME MEASUREMENTS; 2-ELECTRON TRANSFER; METASTABLE LEVELS; COLLISIONS; SLOW; STATE; SPECTROSCOPY AB Penning and Kingdon ion traps have been used to study low-energy multiply-charged ions with charge states up to 80+ during the last few years. The ions have been captured into the traps from beams of external multiply-charged ion sources, or have been produced inside the trap. Measurements of cross sections for electron capture from neutrals to ions and studies of relative double electron capture rates have been completed. The lifetimes of metastable levels of ions, precision spectroscopy on multiply-charged ions in traps, and cooling of trapped ions using lasers, ion-ion elastic collisions, and parallel-tuned circuits, are briefly reviewed. Prospects for the future of highly-charged ions in traps are also discussed. C1 Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Church, DA (reprint author), Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. EM church@physics.tamu.edu NR 37 TC 3 Z9 3 U1 2 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0031-8949 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80A BP 148 EP 153 DI 10.1238/Physica.Topical.080a00148 PG 6 WC Physics, Multidisciplinary SC Physics GA 227RG UT WOS:000082093000031 ER PT J AU Meyer, FW Morozov, VA AF Meyer, FW Morozov, VA TI Multicharged ion-surface interaction studies at ORNL with decelerated beams SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID CHARGE EQUILIBRATION AB We report on studies of low energy multicharged ion-surface interactions carried out at the ORNL MIRF (Multicharged Ion Research Facility) with recently developed apparatus that implements a UHV floating scattering chamber into which beams can be decelerated to interaction energies as low as a few eV per charge. We present initial results, utilizing a TOF system with a biasable drift tube for charge state analysis, of measurements of backscattered projectile energy loss and charge state distributions of multicharged oxygen, and argon ions incident on Au(110), with energies down to a few 100 eV/q. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Meyer, FW (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. NR 7 TC 5 Z9 5 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 226 EP 227 DI 10.1238/Physica.Topical.080a00226 PG 2 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100022 ER PT J AU Smith, ACH Bannister, ME Chung, YS Djuric, N Dunn, GH Wallbank, B Woitke, O AF Smith, ACH Bannister, ME Chung, YS Djuric, N Dunn, GH Wallbank, B Woitke, O TI Near-threshold electron-impact excitation of multiply-charged be-like ions SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID BEAMS AB Absolute total cross sections for excitation of the Be-like ions C(2+), N(3+) and O(4+) at electron energies close to the thresholds have been measured. For all three ions, cross sections for the resonance transition 2s(2) (1)S --> 2s2p (1)p were determined. Theoretical cross sections calculated using close-coupling approximations are in reasonably good agreement with the measured cross sections. Some data were also obtained for transitions from the metastable 2s2p (3)P states of C(2+) and O(4+). C1 UCL, Dept Phys & Astron, London WC1E 6BT, England. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Chungnam Natl Univ, Taejon 3005761, South Korea. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. NIST, Boulder, CO 80309 USA. St Francis Xavier Univ, Antigonish, NS B2G 2W5, Canada. RP Smith, ACH (reprint author), UCL, Dept Phys & Astron, London WC1E 6BT, England. EM banniste@mail.phy.ornl.gov NR 7 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0031-8949 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 283 EP 284 DI 10.1238/Physica.Topical.080a00283 PG 2 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100046 ER EF