FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Shestopalov, AM Kislyi, VP Kruglova, EY Nikishin, KG Semenov, VV Buchanan, AC Gakh, AA AF Shestopalov, AM Kislyi, VP Kruglova, EY Nikishin, KG Semenov, VV Buchanan, AC Gakh, AA TI Preparation of trifluoromethylpyridine libraries SO JOURNAL OF COMBINATORIAL CHEMISTRY LA English DT Article ID PHASE COMBINATORIAL CHEMISTRY; POTENT ANTIBACTERIAL ACTIVITY; REGIOSELECTIVE SYNTHESIS; CHEMICAL LIBRARIES; ORGANIC-SYNTHESIS; CRYSTAL-STRUCTURE; PURIFICATION; DECONVOLUTION; DISCOVERY; MOLECULES AB S-Alkylation followed by heterocyclization of trifluoromethyl-3-cyano-2(1H)-pyridinethiones was used for preparation of libraries of S-alkyl trifluoromethylpyridines and thieno[2,3-b]pyridines. The S-alkylation (in water-DMF mixtures) was successful for all 18 alkylating agents employed (yields typically >50%). S-Alkyl derivatives were further converted to corresponding thieno[2,3-b]pyridines via heterocyclization in base conditions (yields >65%). Structures of new compounds were elucidated by a combination of IR and H-1 NMR spectroscopy and elemental analysis and were confirmed by means of single-crystal X-ray diffraction analysis. C1 ND Zelinskii Organ Chem Inst, Moscow 117913, Russia. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Semenov, VV (reprint author), ND Zelinskii Organ Chem Inst, Leninsky Pr 47, Moscow 117913, Russia. NR 28 TC 14 Z9 14 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-4766 J9 J COMB CHEM JI J. Comb. Chem. PD JAN-FEB PY 2000 VL 2 IS 1 BP 24 EP 28 DI 10.1021/cc990036r PG 5 WC Chemistry, Applied; Chemistry, Medicinal; Chemistry, Multidisciplinary SC Chemistry; Pharmacology & Pharmacy GA 275AQ UT WOS:000084797600007 PM 10750485 ER PT J AU Xu, Y Xu, D Crawford, OH Einstein, JR AF Xu, Y Xu, D Crawford, OH Einstein, JR TI A computational method for NMR-constrained protein threading SO JOURNAL OF COMPUTATIONAL BIOLOGY LA English DT Article; Proceedings Paper CT 4th Annual International Conference on Computational Biology (RECOMB 2000) CY APR 08-11, 2000 CL TOKYO, JAPAN DE protein structure determination; fold recognition; protein threading; NOE restraint; chemical shift index; secondary structure; NMR ID SECONDARY STRUCTURE; CHEMICAL-SHIFT; ALGORITHM; DYNAMICS; CONFORMATIONS; RESTRAINTS; SEQUENCES; DATABASE; FOLDS AB Protein threading provides an effective method for fold recognition and backbone structure prediction, But its application is currently limited due to its level of prediction accuracy and scope of applicability, One way to significantly improve its usefulness is through the incorporation of underconstrained (or partial) NMR data, It is well known that the NMR method for protein structure determination applies only to small proteins and that its effectiveness decreases rapidly as the protein mass increases beyond about 30 kD, We present, in this paper, a computational framework for applying underconstrained NMR data (that alone are insufficient for structure determination) as constraints in protein threading and also in all-atom model construction, In this study, we consider both secondary structure assignments from chemical shifts and NOE distance restraints. Our results have shown that both secondary structure assignments and a small number of long-range NOEs can significantly improve the threading quality in both fold recognition and threading-alignment accuracy, and can possibly extend threading's scope of applicability from homologs to analogs. An accurate backbone structure generated by NMR-constrained threading can then provide a great amount of structural information, equivalent to that provided by many NMR data; and hence can help reduce the number of NMR data typically required for an accurate structure determination. This new technique can potentially accelerate current NMR structure determination processes and possibly expand NMR's capability to larger proteins. C1 Oak Ridge Natl Lab, Div Life Sci, Computat Biol Sect, Oak Ridge, TN 37831 USA. RP Xu, Y (reprint author), Oak Ridge Natl Lab, Div Life Sci, Computat Biol Sect, 1060 Commerce Pk Dr, Oak Ridge, TN 37831 USA. NR 41 TC 15 Z9 16 U1 0 U2 1 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 1066-5277 J9 J COMPUT BIOL JI J. Comput. Biol. PY 2000 VL 7 IS 3-4 BP 449 EP 467 DI 10.1089/106652700750050880 PG 19 WC Biochemical Research Methods; Biotechnology & Applied Microbiology; Computer Science, Interdisciplinary Applications; Mathematical & Computational Biology; Statistics & Probability SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Computer Science; Mathematical & Computational Biology; Mathematics GA 377KK UT WOS:000165512600009 PM 11108473 ER PT J AU Sorenson, JM Head-Gordon, T AF Sorenson, JM Head-Gordon, T TI Matching simulation and experiment: A new simplified model for simulating protein folding SO JOURNAL OF COMPUTATIONAL BIOLOGY LA English DT Article; Proceedings Paper CT 4th Annual International Conference on Computational Biology (RECOMB 2000) CY APR 08-11, 2000 CL TOKYO, JAPAN DE off-lattice models; protein L; protein G; protein folding; multiple histogram method; multi-state kinetics ID SECONDARY STRUCTURE ELEMENTS; BETA-SHEET PROTEIN; RATE-LIMITING STEP; G B1 DOMAIN; CONFORMATIONAL-ANALYSIS; BINDING DOMAIN; KINETICS; COOPERATIVITY; THERMODYNAMICS; PERSPECTIVE AB Simulations of simplified protein folding models have provided much insight into solving the protein folding problem, We propose here a new off-lattice bead model, capable of simulating several different fold classes of small proteins. We present the sequence for an alpha/beta protein resembling the IgG-binding proteins L and G. The thermodynamics of the folding process for this model are characterized using the multiple multihistogram method combined with constant-temperature Langevin simulations, The folding is shown to be highly cooperative, with chain collapse nearly accompanying folding, Two parallel folding pathways are shown to exist on the folding free energy landscape, One pathway contains an intermediate-similar to experiments on protein G, and one pathway contains no intermediates-similar to experiments on protein L, The folding kinetics are characterized by tabulating mean-first passage times, and we show that the onset of glasslike kinetics occurs at much lower temperatures than the folding temperature, This model is expected to be useful in many future contexts: investigating questions of the role of local versus nonlocal interactions in various fold classes, addressing the effect of sequence mutations affecting secondary structure propensities, and providing a computationally feasible model for studying the role of solvation forces in protein folding. 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 Chem, Berkeley, CA 94720 USA. RP Head-Gordon, T (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, 1 Cyclotron Rd,Donner 472, Berkeley, CA 94720 USA. RI Head-Gordon, Teresa/E-5818-2011 NR 46 TC 39 Z9 40 U1 0 U2 5 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 1066-5277 J9 J COMPUT BIOL JI J. Comput. Biol. PY 2000 VL 7 IS 3-4 BP 469 EP 481 DI 10.1089/106652700750050899 PG 13 WC Biochemical Research Methods; Biotechnology & Applied Microbiology; Computer Science, Interdisciplinary Applications; Mathematical & Computational Biology; Statistics & Probability SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Computer Science; Mathematical & Computational Biology; Mathematics GA 377KK UT WOS:000165512600010 PM 11108474 ER PT J AU Mian, IS Dubchak, I AF Mian, IS Dubchak, I TI Representing and reasoning about protein families using generative and discriminative methods SO JOURNAL OF COMPUTATIONAL BIOLOGY LA English DT Article ID HIDDEN MARKOV-MODELS; FOLDING CLASS; SEQUENCE; PREDICTION; DOMAIN; CLASSIFICATION; EXONUCLEASE; DATABASE; HOMOLOGY; GENE AB This work addresses the issues of data representation and incorporation of domain knowledge into the design of learning systems for reasoning about protein families. Given the limited expressive capacity of a particular method, a mixture of protein annotation and fold recognition experts, each implementing a different underlying representation, should provide a robust method for assigning sequences to families. These ideas are illustrated using two data-driven learning methods that make use of different prior information and employ independent, yet complementary, projections of a family: hidden Markov models (HMMs) based on a multiple sequence alignment and neural networks (NNs) based on global sequence descriptors of proteins. Examination of seven protein families indicates that combining a generative (HMM) and a discriminative (NN) method is better than either method on its own. Biologically, human 4-hydroxyphenylpyruvic acid dioxygenase, involved in tyrosinemia type 3, is predicted to be structurally and functionally related to the glyoxalase I family. C1 Lawrence Berkeley Natl Lab, Dept Mol & Cell Biol MS 74 197, Radiat Biol & Environm Toxicol Grp, Div Life Sci, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Natl Energy Res Sci Comp Ctr MS 84 171, Berkeley, CA 94720 USA. RP Mian, IS (reprint author), Lawrence Berkeley Natl Lab, Dept Mol & Cell Biol MS 74 197, Radiat Biol & Environm Toxicol Grp, Div Life Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 37 TC 3 Z9 3 U1 0 U2 0 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 1066-5277 J9 J COMPUT BIOL JI J. Comput. Biol. PY 2000 VL 7 IS 6 BP 849 EP 862 DI 10.1089/10665270050514972 PG 14 WC Biochemical Research Methods; Biotechnology & Applied Microbiology; Computer Science, Interdisciplinary Applications; Mathematical & Computational Biology; Statistics & Probability SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Computer Science; Mathematical & Computational Biology; Mathematics GA 421ET UT WOS:000168049700007 PM 11382366 ER PT J AU Caramana, EJ Rousculp, CL Burton, DE AF Caramana, EJ Rousculp, CL Burton, DE TI A compatible, energy and symmetry preserving Lagrangian hydrodynamics algorithm in three-dimensional Cartesian geometry SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE Lagrangian hydrodynamics; symmetry; three-dimensional; fluid dynamics; Cartesian geometry; shock wave simulation ID ARTIFICIAL VISCOSITY; ERRORS AB This work presents a numerical algorithm for the solution of fluid dynamics problems with moderate to high speed flow in three dimensions. Cartesian geometry is chosen owing to the fact that in this coordinate system no curvature terms are present that break the conservation law structure of the fluid equations. Written in Lagrangian form, these equations are discretized utilizing compatible, control volume differencing with a staggered-grid placement of the spatial variables. The concept of "compatibility" means that the forces used in the momentum equation to advance velocity are also incorporated into the internal energy equation so that these equations together define the total energy as a quantity that is exactly conserved in time in discrete form. Multiple pressures are utilized in each zone; they produce forces that resist spurious vorticity generation. This difficulty can severely limit the utility of the Lagrangian formulation in two dimensions and make this representation otherwise virtually useless in three dimensions. An edge-centered artificial viscosity whose magnitude is regulated by local velocity gradients is used to capture shocks. The particular difficulty of exactly preserving one-dimensional spherical symmetry in three-dimensional geometry is solved. This problem has both practical and pedagogical significance. The algorithm is suitable for both structured and unstructured grids. Limitations that symmetry preservation imposes on the latter type of grids are delineated. C1 Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. RP Caramana, EJ (reprint author), Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, MS-D413, Los Alamos, NM 87545 USA. NR 17 TC 33 Z9 34 U1 0 U2 9 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD JAN 1 PY 2000 VL 157 IS 1 BP 89 EP 119 DI 10.1006/jcph.1999.6368 PG 31 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 273LD UT WOS:000084708400004 ER PT J AU Zhou, SJ Kevrekidis, PG Bishop, AR AF Zhou, SJ Kevrekidis, PG Bishop, AR TI Shear circular dislocation loops investigated with elasticity theory and atomistic simulations SO JOURNAL OF COMPUTER-AIDED MATERIALS DESIGN LA English DT Article DE copper; dislocation; elasticity; molecular dynamics ID SCALE MOLECULAR-DYNAMICS; EMBEDDED-ATOM METHOD AB The elastic fields of displacements, strains, and stresses for a shear circular loop are obtained with the Burgers formula. In addition, interactions between two shear circular loops are obtained based on elasticity theory. A series of molecular dynamics (MD) simulations on a shear circular partial dislocation loop in copper have been performed to examine the elastic solutions. It is found that the results of the MD simulations are in good agreement with those of elasticity theory for a loop with radius similar to 7.5 nm. C1 Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Zhou, SJ (reprint author), TASC, 131 Natl Business Pkwy, Annapolis, MD 20701 USA. NR 23 TC 3 Z9 3 U1 1 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0928-1045 J9 J COMPUT-AIDED MATER JI J. Comput-Aided Mater. Des. PY 2000 VL 7 IS 1 BP 25 EP 42 DI 10.1023/A:1008766500345 PG 18 WC Computer Science, Interdisciplinary Applications; Materials Science, Multidisciplinary SC Computer Science; Materials Science GA 337JK UT WOS:000088353800003 ER PT J AU Dienes, JK Kershner, JD AF Dienes, JK Kershner, JD TI Crack dynamics and explosive burn via generalized coordinates SO JOURNAL OF COMPUTER-AIDED MATERIALS DESIGN LA English DT Article DE burning cracks; explosive sensitivity; fracture dynamics ID HMX AB The growth of cracks and their role in the formation of hot spots in explosives are addressed in a three-part discussion. First the method of generalized coordinates is used to represent crack dynamics with two ordinary differential equations for crack opening and growth. These account for both stable and unstable behavior. Second, the behavior of burning cracks is addressed by coupling those differential equations to a burn model to show that burning cracks can exhibit either mild or violently unstable behavior. Finally, in the third part, it is shown that the burning crack algorithm in combination with SCRAM (which deals with Statistical CRAck Mechanics) can account for the reactive behavior of a plastic-bonded explosive (PBX 9501) Subjected to multiple shocks. SCRAM allows for representation of brittle behavior in a variety of explosives, propellants, ceramics and geological materials. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Dienes, JK (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 25 TC 0 Z9 1 U1 1 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0928-1045 J9 J COMPUT-AIDED MATER JI J. Comput-Aided Mater. Des. PY 2000 VL 7 IS 3 BP 217 EP 237 DI 10.1023/A:1011874909560 PG 21 WC Computer Science, Interdisciplinary Applications; Materials Science, Multidisciplinary SC Computer Science; Materials Science GA 480BK UT WOS:000171440400006 ER PT J AU Boyle, TJ Tafoya, CJ Scott, BL Ziller, JW AF Boyle, TJ Tafoya, CJ Scott, BL Ziller, JW TI Coordination compounds of strontium: Syntheses characterizations, and crystal structures of [Sr(mu-ONc)(2)(HONc)(4)](2) and Sr-5(mu(4)-O)(mu(3)-ONep)(4)(mu-ONep)(4)(HONep)(solv)(4)(ONc = O2CCH2CMe3; Nep = Ch(2)CMe(3); solv = tetrahydrofuran or 1-methyl-imidazole) SO JOURNAL OF COORDINATION CHEMISTRY LA English DT Article DE metal alkoxide; strontium; neo-pentoxide; t-butyl acetate ID SRBI2TA2O9 THIN-FILMS; CHEMICAL-VAPOR-DEPOSITION; FERROELECTRIC PROPERTIES; ELECTRICAL-PROPERTIES; BOTTOM ELECTRODE; CAPACITORS; BISMUTH; BARIUM; PHASE AB We have synthesized and characterized two novel Sr compounds: [Sr(mu-ONc)(2)(HONc)(4)](2) (1, ONc=O2CCH2CMe3), and Sr-5(mu(4)-O)(mu(3)-ONep)(4)(mu-ONep)(4)(HONep)(solv)(4) [ONep=OCH2CMe3, solv=tetrahydrofuran (THF), 2a; 1-methyl-imidazole (MeIm), 2b], that demonstrate increased solubility in comparison to the commercially available Sr precursors. The two metal centers of 1 share four unidentate bridging mu-ONc ligands and complete their octahedral geometry through coordination of four monodentate terminal HONc ligands. The structural arrangement of the central core of 2a and 2b are identical, wherein four octahedral Sr atoms are arranged in a square geometry around a mu(4)-O ligand. An additional seven-coordinated Sr atom sits directly atop the mu(4)-O to form a square-pyramidal arrangement of the Sr atoms, but the apical Sr-O distance is too long to be considered a bond. In solution, compound 1 is disrupted forming a monomer but 2a and 2b retain their structures. C1 Sandia Natl Labs, Dept 1846, Adv Mat Lab, Albuquerque, NM 87106 USA. Univ Calif Los Alamos Natl Lab, CST 18, Chem Sci & Technol Div, Xray Diffract Lab, Los Alamos, NM 87545 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92717 USA. RP Boyle, TJ (reprint author), Sandia Natl Labs, Dept 1846, Adv Mat Lab, 100 Univ Blvd SE, Albuquerque, NM 87106 USA. RI Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 38 TC 8 Z9 8 U1 1 U2 1 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0095-8972 J9 J COORD CHEM JI J. Coord. Chem. PY 2000 VL 51 IS 4 BP 361 EP 378 DI 10.1080/00958970008055141 PG 18 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 345BJ UT WOS:000088795300004 ER PT J AU Friedman, DJ Norman, AG Geisz, JF Kurtz, SR AF Friedman, DJ Norman, AG Geisz, JF Kurtz, SR TI Comparison of hydrazine, dimethylhydrazine, and t-butylamine nitrogen sources for MOVPE growth of GaInNAs for solar cells SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE GaInNAs; hydrazine; dimethylhydrazine; t-butylamine; solar cells ID CHEMICAL-VAPOR-DEPOSITION; MOLECULAR-BEAM EPITAXY; LASER-DIODES; GAN; SEMICONDUCTORS; PERFORMANCE; NUCLEATION; GAASN AB Dimethylhydrazine (DMHy) has been shown to be an effective nitrogen source for the growth of the alloy Ga1-xInxNyAs1-y (x, y much less than 1). However, high DMHy flow rates are required, and low diffusion lengths and high p-type background doping concentration are typically observed in the grown material. It is therefore of interest to evaluate alternative nitrogen sources. Here, we evaluate two such sources: hydrazine and tertiarybutylamine. Hydrazine is of particular interest because it contains no carbon, suggesting that it might yield lower p-type background doping than DMHy does. With tertiarybutylamine, no nitrogen incorporation was observed. even with nitrogen/III ratios as high as 2000, and so does not appear promising. With hydrazine, by contrast, significant nitrogen incorporation was observed, even at much lower nitrogen/III ratios than would be required using DMHy. However, the p-type background doping appears no lower than with DMHy. (C) 2000 Elsevier Science B.V. All rights reserved. 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 23 TC 18 Z9 18 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD JAN PY 2000 VL 208 IS 1-4 BP 11 EP 17 DI 10.1016/S0022-0248(99)00523-0 PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 269PH UT WOS:000084486400002 ER PT J AU Choi, BW Wadley, HNG AF Choi, BW Wadley, HNG TI In situ studies of Cd1-xZnxTe nucleation and crystal growth SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE II-VI semiconductor crystals growth; multifrequency eddy current sensor; finite element analysis; vertical Bridgman growth; CdZnTe; liquid-solid interface location ID VERTICAL BRIDGMAN GROWTH; HEAT-TRANSFER; CDTE; CONDUCTIVITY; TELLURIDE AB The nucleation and growth of Cd1-xZnxTe crystals in a multi-zone vertical Bridgman growth furnace have been observed and measured using in situ eddy current sensor techniques. A two-coil eddy current sensor measured coil impedance changes for multifrequency which were then interpreted using an electromagnetic finite element analysis. The sensor was used to characterize the initial melting of a charge and the subsequent nucleation of solid during solidification. Fully remelted in situ compounded charges were exposed to significant melt superheating and were found to undergo large melt undercoolings (of up to 20 degrees C), spontaneous crystal nucleation and rapid solidification (velocities approaching 60 mm/h which was more than 10 times the furnace translation rate). Post-growth metallography revealed that about 20 mm of polycrystalline solid was formed in this way before recalescence arrested the solidification interface. In partially remelted charges neither undercooling nor unstable growth were observed. These results indicate that eddy current sensors can be used to monitor critical aspects of the vertical Bridgman crystal growth of semiconducting materials and may simplify the implementation of seeded crystal growth concepts in this, and other, semiconductor crystal growth processes. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Virginia, Intelligent Proc Mat Lab, Sch Engn & Appl Sci, Charlottesville, VA 22903 USA. RP Choi, BW (reprint author), Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, 7000 East Ave, Livermore, CA 94550 USA. NR 19 TC 14 Z9 16 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD JAN PY 2000 VL 208 IS 1-4 BP 219 EP 230 DI 10.1016/S0022-0248(99)00536-9 PG 12 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 269PH UT WOS:000084486400033 ER PT J AU Land, TA De Yoreo, JJ AF Land, TA De Yoreo, JJ TI The evolution of growth modes and activity of growth sources on canavalin investigated by in situ atomic force microscopy SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE growth mode; growth source; atomic force microscopy; canavalin ID CRYSTAL-GROWTH; SURFACE-MORPHOLOGY; VIRUS CRYSTALS; SPIRAL GROWTH; CRYSTALLIZATION; KINETICS; PROTEIN; MECHANISMS; FACE; DIFFUSION AB In situ atomic force microscopy has been used to investigate the evolution of growth modes and the activity of dislocation sources as a function of supersaturation during canavalin crystal growth. The results presented here show that, depending on the supersaturation, growth occurs on monomolecular steps generated either by simple or complex screw dislocation sources, 2D nucleating islands, or macroclusters that sediment onto the surface before spreading laterally as step bunches. We have observed the process of an individual dislocation source generating new steps which can be used to directly measure the critical length necessary for steps to advance. The activity of various dislocation sources are investigated as a function of supersaturation. A comparison of fundamental materials parameters for canavalin and a variety of other systems show systematic scaling. The kinetic coefficient decreases as the molecular complexity increases and the supersaturation at which 2D nucleation is observed increases with step free energy. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94551 USA. RP Land, TA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, POB 5508, Livermore, CA 94551 USA. NR 41 TC 56 Z9 59 U1 2 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD JAN PY 2000 VL 208 IS 1-4 BP 623 EP 637 DI 10.1016/S0022-0248(99)00470-4 PG 15 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 269PH UT WOS:000084486400083 ER PT J AU Campbell, AA Seth, ML Li, X Long, R Shaw, WJ Drobny, GP Stayton, PS AF Campbell, AA Seth, ML Li, X Long, R Shaw, WJ Drobny, GP Stayton, PS TI Interactions of statherin and statherin peptides with hydroxyapatite crystals. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Pacific NW Natl Lab, Richland, WA USA. Univ Washington, Seattle, WA 98195 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 2000 VL 79 SI SI MA 71 BP 152 EP 152 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 277MH UT WOS:000084937000068 ER PT J AU Tomsia, AP Gomez-Vega, JM Saiz, E Marshall, GW Marshall, SJ AF Tomsia, AP Gomez-Vega, JM Saiz, E Marshall, GW Marshall, SJ TI Glass-hydroxyapatite composites applies as coatings on Ti6Al4V implants. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. Univ Calif San Francisco, San Francisco, CA 94143 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 2000 VL 79 SI SI MA 1711 BP 357 EP 357 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 277MH UT WOS:000084937001703 ER PT J AU Palmer, RJ Hansen, MC White, DC AF Palmer, RJ Hansen, MC White, DC TI Flowcell culture of Porphyromonas gingivalis biofilms under anaerobic conditions. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37932 USA. Tech Univ Denmark, DK-2800 Lyngby, Denmark. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 2000 VL 79 SI SI MA 2222 BP 421 EP 421 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 277MH UT WOS:000084937002217 ER PT J AU Xin, Y James, EM Browning, ND Pennycook, SJ AF Xin, Y James, EM Browning, ND Pennycook, SJ TI Atomic resolution Z-contrast imaging of semiconductors SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Article DE atomic resolution Z-contrast imaging; semiconductors ID ENERGY-LOSS SPECTROSCOPY; MOLECULAR-BEAM EPITAXY; LIGHT-EMITTING-DIODES; GRAIN-BOUNDARY; CORE STRUCTURES; GAN FILMS; DISLOCATION; GROWTH; CRYSTALS; STEM AB The direct interpretability of atomic resolution Z-contrast images obtained from a scanning transmission electron microscope (STEM) makes this imaging technique particularly powerful for the analysis of interfaces and defects in semiconductor materials and devices. In this paper, the principles of the technique are outlined and representative examples of its use are presented. In particular, we show the use of Z-contrast imaging to determine the polarity of a CdTe film grown on a Si substrate, the atomic structures of stacking faults and threading dislocation cores in GaN, and the atomistic structure of an ohmic metal/semiconductor contact of Au/GaAs. C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Xin, Y (reprint author), Univ Illinois, Dept Phys, Chicago, IL 60607 USA. OI Browning, Nigel/0000-0003-0491-251X NR 36 TC 5 Z9 5 U1 1 U2 5 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 2000 VL 49 IS 2 BP 231 EP 244 PG 14 WC Microscopy SC Microscopy GA 313NE UT WOS:000087005100005 ER PT J AU Voyles, PM Gibson, JM Treacy, MMJ AF Voyles, PM Gibson, JM Treacy, MMJ TI Fluctuation microscopy: a probe of atomic correlations in disordered materials SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Article DE fluctuation microscopy; medium-range order; disordered materials; amorphous semiconductors; quantitative microscopy ID SILICON; INFORMATION; COHERENCE; IMAGES; ORDER AB Fluctuation microscopy is a new technique to study medium-range structure in disordered materials. Low-resolution dark-field transmission electron microscope images are interpreted as spatially resolved diffraction maps. Statistical analysis of intensity variations in these maps provides information about higher-order atom position correlation functions. Here we give a qualitative description of the technique and explore the properties and utility of higher-order correlation functions in describing the structure of disordered materials. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. NEC Res Inst, Princeton, NJ 08540 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Voyles, PM (reprint author), Univ Illinois, Dept Phys, 1110 W Green St, Urbana, IL 61801 USA. RI Gibson, Murray/E-5855-2013; OI Gibson, Murray/0000-0002-0807-6224; Voyles, Paul/0000-0001-9438-4284 NR 22 TC 58 Z9 58 U1 0 U2 12 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 2000 VL 49 IS 2 BP 259 EP 266 PG 8 WC Microscopy SC Microscopy GA 313NE UT WOS:000087005100007 ER PT J AU Liliental-Weber, Z AF Liliental-Weber, Z TI Derivation of growth mechanism of nano-defects in GaN from TEM data SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Article DE GaN; impurities; dopants; dislocations; pinholes; nanotubes ID LIGHT-EMITTING-DIODES; ELECTRON-DIFFRACTION; THIN-FILMS; DISLOCATIONS; MICROSCOPY; NANOPIPES; LAYERS AB Transmission electron microscopy (TEM) has been used to describe 'hollow' defects, e.g. nanotubes and pinholes (empty inside) formed in GaN hetero- and homoepitaxial layers. These defects are believed to be formed due to the presence of impurities and dopants. These defects appear to be even more deleterious than dislocations for the application of GaN in devices because their formation interrupts two-dimensional growth of quantum wells, and therefore will influence electrical and optical properties of the material. Experimental observations show that both these defects start from V-shaped indentations delineated by (10 (1) over bar 1) planes, and their density increases with higher concentrations of impurities or dopants. These 'hollow' defects are often found to be attached to dislocations, but the frequently observed termination of these defects inside the crystal eliminates dislocations as the source of these defects. Theoretical predictions also do not suggest that dislocations would have large-diameter empty cores like these of nanotubes and pinholes. C1 Lawrence Berkeley Natl Lab, Div Mat Sci, Ctr Adv Mat, Berkeley, CA 94720 USA. RP Lawrence Berkeley Natl Lab, Div Mat Sci, Ctr Adv Mat, Berkeley, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 36 TC 22 Z9 22 U1 0 U2 11 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 EI 1477-9986 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 2000 VL 49 IS 2 BP 339 EP 348 PG 10 WC Microscopy SC Microscopy GA 313NE UT WOS:000087005100016 ER PT J AU Rafferty, B Pennycook, SJ Brown, LM AF Rafferty, B Pennycook, SJ Brown, LM TI Zero loss peak deconvolution for bandgap EEL spectra SO JOURNAL OF ELECTRON MICROSCOPY LA English DT Article DE scanning transmission electron microscopy; electron energy loss spectroscopy; deconvolution; optoelectronic ID ELECTRON-ENERGY-LOSS; LOSS SPECTROSCOPY; BEAMS AB This paper shows how bandgap EEL spectra are commonly processed either by deconvolution or subtraction methods in an attempt to remove effects arising from the finite width and long tail of the zero loss peak. This paper will compare the two main methods, and show that the deconvolution method is significantly more reliable and free of user-interpretation or artefacts. We first consider how the zero loss peak is produced and what effects experimental conditions have upon it, and then show that only by the deconvolution method can accurate bandgap energies and bandgap densities of states be determined. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England. RP Rafferty, B (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 17 TC 25 Z9 25 U1 5 U2 17 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0744 J9 J ELECTRON MICROSC JI J. Electron Microsc. PY 2000 VL 49 IS 4 BP 517 EP 524 PG 8 WC Microscopy SC Microscopy GA 347MV UT WOS:000088934500001 PM 12005190 ER PT J AU Ynzunza, RX Daimon, H Palomares, FJ Tober, ED Wang, Z de Abajo, FJG Morais, J Denecke, R Kortright, JB Hussain, Z Van Hove, MA Fadley, CS AF Ynzunza, RX Daimon, H Palomares, FJ Tober, ED Wang, Z de Abajo, FJG Morais, J Denecke, R Kortright, JB Hussain, Z Van Hove, MA Fadley, CS TI Circular dichroism in core photoelectron emission from (1x1) oxygen on W(110): experiment and multiple-scattering theory SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article DE electron-solid interactions, scattering, diffraction; photoelectron diffraction; synchrotron radiation photoelectron spectroscopy; tungsten; oxygen; low index single crystal surfaces ID POLARIZED X-RAYS; LEVEL PHOTOEMISSION; ANGULAR-DISTRIBUTION; ULTRATHIN FILMS; CROSS-SECTIONS; DIFFRACTION; ABSORPTION; RESOLUTION; FE/CU(001); SI(001) AB We have measured the circular dichroism in angular distributions (CDAD) of W 4f emission from a stable one-monolayer structure of oxygen on W(110) that is locally (1X1) in character. Photoelectrons were excited at kinetic energies of approximately 250 eV from the two chemically-shifted peaks present in these spectra (for bulk W and 'oxide' W bound to three O atoms) using right and left circularly polarized radiation (RCP and LCP, respectively), as well as linearly polarized radiation (LP) to provide a reference data set. Measurements were made over a large fraction of the solid angle above the surface, using a new beamline and experimental station at the Advanced Light Source. In switching between RCP and LCP, the data are found to show large CDAD effects of up to +/-50%, as well as both peak 'rotation' effects las first discussed by Daimon et al. in measurements on Si(100)), and more complex changes that are not so simply described. Multiple scattering diffraction calculations are found to very well reproduce all of the effects seen experimentally, and to represent a more accurate way of dealing with such effects than a prior peak rotation model. The LP data is also found to closely resemble the sum of the RCP and LCP intensities, and this is quantitatively explained. Such CDAD effects are thus expected to be generally seen in all work in solid materials, and important to allow for in studies of magnetic materials, with multiple scattering theory expected to yield a quantitative description of hem. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Nara Inst Sci & Technol, Nara 63001, Japan. RP Fadley, CS (reprint author), Lawrence Berkeley Natl Lab, Div Mat Sci, Mailstop 2-100, Berkeley, CA 94720 USA. RI Van Hove, Michel/A-9862-2008; Palomares, Francisco Javier/C-4605-2011; Garcia de Abajo, Javier/A-6095-2009; Morais, Jonder/E-5022-2013 OI Van Hove, Michel/0000-0002-8898-6921; Palomares, Francisco Javier/0000-0002-4768-2219; Garcia de Abajo, Javier/0000-0002-4970-4565; Morais, Jonder/0000-0002-4143-1208 NR 34 TC 13 Z9 13 U1 2 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD JAN PY 2000 VL 106 IS 1 BP 7 EP 28 DI 10.1016/S0368-2048(99)00083-3 PG 22 WC Spectroscopy SC Spectroscopy GA 274BP UT WOS:000084744100002 ER PT J AU Peake, GM Zhang, L Li, NY Sarangan, AM Willison, CG Shul, RJ Hersee, SD AF Peake, GM Zhang, L Li, NY Sarangan, AM Willison, CG Shul, RJ Hersee, SD TI A micromachined, shadow-mask technology for the OMVPE fabrication of integrated optical structures SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 5th Biennial Workshop on Organometallic Vapor Phase Epitaxy CY MAY 23-27, 1999 CL PONTE VEDRA BEACH, FLORIDA DE OMVPE; MOCVD; SMG; shadow mask; nonplanar epitaxy; integrated optics; micromachining; microoptics; direct fusion bonding ID MOVPE GROWTH; LASER AB A micromachined, silicon shadow-mask technology is described which extends the capabilities of shadow-masked OMVPE for the fabrication of nonplanar micro-optical elements. The deep reactive ion etched (DRIE) shadow mask is inexpensive, reusable and produces smooth, nonplanar structures with precise control of position, shape and size. Direct fusion bonding of the mask to the substrate was found to be a reliable and reproducible method for attaching the mask to the substrate during growth. The DRIE shadow mask technology allows the deposition of microlenses with focal lengths out to 3 mm without the central flattening that was previously observed in shadow masked lenses grown under the epitaxial mask. We also describe novel applications of this technology in the fabrication of micromirrors and concentrically-variable Bragg reflectors, which should improve mode discrimination in large aperture VCSELs. C1 Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87106 USA. Univ New Mexico, Dept Elect & Comp Engn, Albuquerque, NM 87106 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Peake, GM (reprint author), Univ New Mexico, Ctr High Technol Mat, 1313 Goddard SE, Albuquerque, NM 87106 USA. NR 16 TC 5 Z9 5 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD JAN PY 2000 VL 29 IS 1 BP 86 EP 90 DI 10.1007/s11664-000-0100-x PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 278WN UT WOS:000085012100017 ER PT J AU Biefeld, RM Phillips, JD Kurtz, SR AF Biefeld, RM Phillips, JD Kurtz, SR TI Exploring new active regions for type IInAsSb strained-layer lasers SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 5th Biennial Workshop on Organometallic Vapor Phase Epitaxy CY MAY 23-27, 1999 CL PONTE VEDRA BEACH, FLORIDA ID CHEMICAL-VAPOR-DEPOSITION; LIGHT-EMITTING-DIODES; MIDINFRARED LASERS AB We report on the metal-organic chemical vapor deposition (MOCVD) of midinfrared InAsSb/InPSb optically pumped lasers grown using a high speed rotating disk reactor (RDR). The devices contain AlAsSb cladding layers and strained, type I, InAsSb/InPSb active regions. By changing the layer thickness and composition of InAsSb/InPSb SLSs, we have prepared structures with low temperature (<20 K) photoluminescence wavelengths ranging from 3.4 mu m to 4.8 mu m. We find a variation of bandgap from 0.272 to 0.324 eV for layer thicknesses of 9.0 to 18.2 nm. From these data we have estimated a valence band offset for the InAsSb/InPSb interface of about 400 meV. An InAsSb/InPSb SLS, optically pumped laser structure was grown on an InAs substrate with AlAs0.16Sb0.84 cladding layers. A lasing threshold and spectrally narrowed laser emission were seen from 80 K through 240 K, the maximum temperature where lasing occurred. The temperature dependence of the SLS laser threshold is described by a characteristic temperature, T-0 = 72 K, from 80 K to 200 K. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Biefeld, RM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Phillips, Jamie/E-9394-2010 NR 5 TC 3 Z9 3 U1 1 U2 3 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD JAN PY 2000 VL 29 IS 1 BP 91 EP 93 DI 10.1007/s11664-000-0101-9 PG 3 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 278WN UT WOS:000085012100018 ER PT J AU Odedra, R Smith, LM Rushworth, SA Ravetz, MS Clegg, J Kanjolia, R Irvine, SJC Ahmed, MU Bourret-Courchesne, ED Li, NY Cheng, J AF Odedra, R Smith, LM Rushworth, SA Ravetz, MS Clegg, J Kanjolia, R Irvine, SJC Ahmed, MU Bourret-Courchesne, ED Li, NY Cheng, J TI 1,1-dimethylhydrazine as a high purity nitrogen source for MOVPE-water reduction and quantification using nuclear magnetic resonance, gas chromatography-atomic emission detection spectroscopy and cryogenic-mass spectroscopy analytical techniques SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 5th Biennial Workshop on Organometallic Vapor Phase Epitaxy CY MAY 23-27, 1999 CL PONTE VEDRA BEACH, FLORIDA DE hydrazines; dimethylhydrazine; MOVPE; nitrogen source ID MOLECULAR-BEAM EPITAXY; CUBIC GAN; GROWTH; DIMETHYLHYDRAZINE; ZNSE AB Hydrazine derivatives are attractive low temperature nitrogen sources for use in MOVPE due to their low thermal stability. However their purification and subsequent analysis has not previously been investigated in depth for this application. A detailed study on 1,1-dimethylhydrazine {(CH3)(2)N-NH2} purified by eight different methods and the subsequent quantitative measurements of water present in the samples obtained is reported here. A correlation between H-1 nuclear magnetic resonance spectroscopy (NMR), gas chromatography-atomic emission detection (GC-AED) and cryogenic mass spectroscopy (Cryogenic-MS) has been performed. All three analysis techniques can be used to measure water in the samples and with the best purification the water content can be lowered well below 100 ppm. The high purity of this material has been demonstrated by growth results and the state-of-the-art performance of laser diodes. C1 Epichem Ltd, Wirral CH62 3QF, Merseyside, England. Epichem Inc, Haverhill, MA 01835 USA. NEWI, Optoelect Mat Res Lab, Wrexham LL11 2AW, Clwyd, Wales. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87106 USA. RP Odedra, R (reprint author), Epichem Ltd, Power Rd, Wirral CH62 3QF, Merseyside, England. NR 14 TC 6 Z9 6 U1 1 U2 8 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD JAN PY 2000 VL 29 IS 1 BP 161 EP 164 DI 10.1007/s11664-000-0113-5 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 278WN UT WOS:000085012100030 ER PT J AU Cuadrado, JA Zhang, WX Hang, W Majidi, V AF Cuadrado, JA Zhang, WX Hang, W Majidi, V TI Speciation of gold(III)-L-histidine complex: a multi-instrumental approach SO JOURNAL OF ENVIRONMENTAL MONITORING LA English DT Article ID PLASMA-MASS SPECTROMETRY; AMINO-ACIDS; GOLD(III); HISTIDINE AB The formation and structure of gold (III)-L-histidine complex was investigated with the use of carbon (C-13) and proton (H-1) nuclear magnetic resonance (NMR), infrared (IR) spectroscopy, capillary electrophoresis (CE), capillary electrophoresis-inductively coupled plasma-mass spectroscopy (CE-ICP-MS), X-ray fluorescence spectroscopy (XRF), matrix-assisted laser desorption/ionization (MALDI), and laser desorption mass spectroscopy (LDMS). It was found that two L-histidine molecules and one gold ion slowly form a complex in acidic solution. Each L-histidine molecule provided two nitrogen ligands; one was the alpha-amino group and the other from the imidazole ring. The Au(III)-bis-L-histidine complex precipitates after deprotonation of the free carboxylic group, resulting in an increase in the solution acidity. Determination of the exact sequence of events and the identity of the complex was a comprehensive instrumental analysis problem involving the above techniques. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. St Jude Childrens Res Hosp, Dept Biol Struct, Memphis, TN 38105 USA. RP Majidi, V (reprint author), Univ Calif Los Alamos Natl Lab, MS K484, Los Alamos, NM 87545 USA. NR 15 TC 22 Z9 22 U1 1 U2 8 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1464-0325 J9 J ENVIRON MONITOR JI J. Environ. Monit. PY 2000 VL 2 IS 4 BP 355 EP 359 DI 10.1039/b000085j PG 5 WC Chemistry, Analytical; Environmental Sciences SC Chemistry; Environmental Sciences & Ecology GA 338TX UT WOS:000088440300015 PM 11249792 ER PT J AU Harley, NH Chittaporn, P Fisenne, IM Perry, P AF Harley, NH Chittaporn, P Fisenne, IM Perry, P TI Rn-222 decay products as tracers of indoor and outdoor aerosol particle size SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Article DE radon decay product aerosols; indoor aerosols; outdoor aerosols; lead-210 aerosol measurements ID RADON AB Measurements of the air concentration of Pb-210 indoors and outdoors were made at a single-family suburban home in northern New Jersey over a 1.5 year period. A sampler with 5 fine mesh screens and a backup Millipore filter was used to determine the indoor and outdoor ultrafine particle size distribution. A sample of the total airborne particulates was collected simultaneously. The long-lived Rn-222 decay product Pb-210 presents a unique and highly sensitive tracer to study atmospheric aerosol particles. The aerosol particle size sampler integrates ultrafine particulates deposited over 3-4 weeks. The measurement of Pb-210 (Po-210) on the screens and filter was performed using very low background alpha scintillation counters (3-5 counts/day), and long count times (5000 min). Deconvolution of the alpha counting data was performed using an extreme value estimation program (EVE) that provides an accurate evaluation of the particle size distribution. The particle size data show that a significant fraction (20-60%) of the atmospheric aerosol particles in this suburban location are in the ultrafine region. The indoor to outdoor Pb-210 ratio revealed that 65% of the outdoor aerosol particles in this suburban location comprise the indoor particle concentration. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 NYU, Sch Med, Nelson Inst Environm Med, New York, NY 10016 USA. US DOE, Environm Measurements Lab, New York, NY 10014 USA. RP Harley, NH (reprint author), NYU, Sch Med, Nelson Inst Environm Med, 550 1st Ave,MSB Room C-90, New York, NY 10016 USA. NR 13 TC 7 Z9 8 U1 1 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 2000 VL 51 IS 1 BP 27 EP 35 DI 10.1016/S0265-931X(00)00042-4 PG 9 WC Environmental Sciences SC Environmental Sciences & Ecology GA 322RR UT WOS:000087523000004 ER PT J AU Cavallo, AJ AF Cavallo, AJ TI Understanding mine aerosols for radon risk assessment SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Article DE 3uranium mine aerosols; hardrock mine aerosols; diesel power mine aerosols; aerosol particle behaviour; radon risk assessment ID URANIUM-MINE; SIZE DISTRIBUTION; PARTICLES; PROGENY; MODEL; ICRP AB The radon risk-coefficient, determined from long-term epidemiology studies of 11 groups of uranium and hardrock miners, is given in terms of exposure to airborne radon progeny, not lung dose, which must be computed using breathing rates and the airborne radioactivity as a function of particle size in the mine atmosphere. Aerosol measurements relevant to this issue are reviewed: in diesel-powered mines the range of activity median diameters is between 75 and 175 nm (GSD = 2), and these aerosols are expected to be hydrophobic and not double in size in the respiratory tract as is often assumed. However, since much of the exposure occurred in mines powered electrically or with compressed air, and few activity size distribution measurements have been made in such mines, it appears that further experimental work is needed to characterize the properties of aerosols to be expected in the working environments of the mines under consideration. Published by Elsevier Science Ltd. C1 US DOE, Environm Measurements Lab, New York, NY 10014 USA. RP Cavallo, AJ (reprint author), US DOE, Environm Measurements Lab, 201 Varick St,5th Floor, New York, NY 10014 USA. NR 46 TC 7 Z9 8 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 2000 VL 51 IS 1 BP 99 EP 119 DI 10.1016/S0265-931X(00)00047-3 PG 21 WC Environmental Sciences SC Environmental Sciences & Ecology GA 322RR UT WOS:000087523000009 ER PT J AU Wasiolek, PT James, AC AF Wasiolek, PT James, AC TI Unattached fraction measuring technique and radon lung dose SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Article DE unattached fraction; radon lung dose; stainless steel wire-mesh screens; aerosol activity size distribution; outdoor aerosols ID ACTIVITY SIZE DISTRIBUTIONS; SCREEN DIFFUSION BATTERIES; DECAY PRODUCTS; WIRE SCREENS; PROGENY; DAUGHTERS AB We examined the influence of measurement techniques used to characterize the ultrafine fraction of airborne radon progeny on the estimation of dose rate received by the lungs by comparing simultaneous measurements of the unattached fraction and the full activity-weighted size distribution. The unattached fraction was measured using a single stainless steel-win-mesh screen (50% penetration for 4 nm equivalent diameter particles). The full activity-weighted size distribution was measured using a graded-screen array (six stages with equivalent particle diameter for 50% penetration ranging from 0.5 to 500 nm). Thirty paired samples were taken outdoors in a rural location in central New Mexico, USA. Using current exposure-dose conversion factors based on the ICRP 66 Lung Model, we compared the calculated effective dose rate for the respiratory tract for each sample pair. On average, the dose calculated from the full radon-progeny particle-size distribution (graded-screen array measurements) was 80% higher than that calculated from the single-screen measurements. Our results raise questions about the accuracy (i.e,, potential low bias) of retrospective dose estimates for miners and other radon-exposed groups for whom the dose assessment was based on the nominal unattached fraction measured with a single screen. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Los Alamos Natl Lab, Hlth Phys Measurements Grp, Los Alamos, NM 87545 USA. ACJ & Associates, Richland, WA 99352 USA. RP Los Alamos Natl Lab, Hlth Phys Measurements Grp, ESH-4, Los Alamos, NM 87545 USA. EM wasiolek@lanl.gov NR 40 TC 10 Z9 14 U1 1 U2 6 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X EI 1879-1700 J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 2000 VL 51 IS 1 BP 137 EP 151 DI 10.1016/S0265-931X(00)00049-7 PG 15 WC Environmental Sciences SC Environmental Sciences & Ecology GA 322RR UT WOS:000087523000011 ER PT J AU Abraham, JP Whicker, FW Hinton, TG Rowan, DJ AF Abraham, JP Whicker, FW Hinton, TG Rowan, DJ TI Inventory and spatial pattern of Cs-137 in a pond: a comparison of two survey methods SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Article DE cesium; TLD; sediment cores; exposure rate; inventory ID SEDIMENTS; LAKE; RESERVOIR; RADIONUCLIDES; MOBILIZATION; RADIOCESIUM AB The sediments of Pond A, a former Savannah River Site cooling pond for R-reactor, were contaminated with Cs-137 between 1954 and 1964. Pond A is unique because it is very shallow and contains an extremely high density of aquatic vegetation and old, undecomposed tree stumps which modify normal sedimentation processes and cause special radiological characterization challenges. To determine the most efficient technique for estimating inventory and spatial patterns of Cs-137, We measured exposure rates at 124 sediment surface locations with two types of thermoluminescent dosimeters (TLDs) and compared them to estimates calculated from Cs-137 measured in 58 extracted sediment cores. The mean net exposure rate(+/- 1SEM) measured at the sediment water interface with a UD-802 multi-element TLD (differentially shielded lithium berate and calcium sulfate) was 40 +/- 4 mu R h(-1), while the corresponding value measured with a CaF2, TLD was 64 +/- 10 mu R h(-1). Both sets of TLD measurements were found to correlate well with each other (R-2 = 0.88, p < 0.001), and moderately well with theoretical calculations derived from Cs-137 activity concentrations measured in sediment cores (R-2 > 0.50). The corresponding mean exposure rate calculated from the sediment data, 69 +/- 10 mu R h(-1), was likely an over-estimate resulting from the core sampling bias created by the large number of tree stumps. Overall, peak Cs-137 activity occurred at similar to 2-4 cm depth in the sediment cores, with > 99% in the top 20 cm of sediment. The total Cs-137 inventory of Pond A was estimated as 4.1 +/- 0.5 x 10(10) Bq, with most activity located in the deeper portions. Approximately 1% of the Cs-137 activity thought to have been released by R-Reactor can be accounted for in Pond A, with an additional 53% estimated from other work to be in the much larger Pond B, and Par Pond, located further down the drainage. However, the mean deposition in Pond A (7.9 x 10(9) Bq ha(-1)) was higher than either Pond B (4.0 x 10(9) Bq ha(-1)), or Par Pond (1.4 x 10(9) Bq ha(-1)). It was concluded that, although the TLD method was more efficient and could employ more sampling locations to estimate spatial pattern, a reasonable amount of coring was essential to determine depth distribution, radionuclide composition, and to interpret the TLD data. Optimal estimation and characterization efficiency can benefit from simultaneous application of both techniques. Published by Elsevier Science Ltd. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. Colorado State Univ, Dept Radiol Hlth Sci, Ft Collins, CO 80523 USA. RP Hinton, TG (reprint author), Univ Georgia, Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. NR 14 TC 5 Z9 5 U1 1 U2 7 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 2000 VL 51 IS 2 BP 157 EP 171 DI 10.1016/S0265-931X(00)00052-7 PG 15 WC Environmental Sciences SC Environmental Sciences & Ecology GA 331GW UT WOS:000088010800002 ER PT J AU Hinton, T AF Hinton, T TI Strong inference, science fairs, and radioecology SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Editorial Material C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Hinton, T (reprint author), Univ Georgia, Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 2000 VL 51 IS 3 BP 277 EP 279 DI 10.1016/S0265-931X(00)00090-4 PG 3 WC Environmental Sciences SC Environmental Sciences & Ecology GA 335FL UT WOS:000088233200001 ER PT J AU Lewis, GP Taylor, BE Pinder, JE Dixon, PM AF Lewis, GP Taylor, BE Pinder, JE Dixon, PM TI Apparent decline of the sediment Cs-137 inventory of an abandoned reactor cooling reservoir: export or uncertainty? SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Article DE radiocesium; Cs-137; sediments; lakes; reservoir; inventories; remobilisation ID CANADIAN SHIELD LAKE; MACROPHYTES; CO-60 AB In lakes and reservoirs, variability among sediment samples can mask temporal changes in radionuclide inventories. For Pond B, an abandoned reactor cooling reservoir in South Carolina, USA, we determined if a decline in the sediment Cs-137 inventory beyond radioactive decay could be detected over a IO-yr interval. Because the 95% confidence interval for the decay-corrected change in inventory (- 7.7% to + 0.8% yr(-1)) included 0, we could not conclusively determine that a change in inventory beyond radioactive,decay had occurred. Given the sample size of 30 pairs of sediment cores, the minimum change that could be detected reliably would have been - 5.8% yr(-1). By contrast, we estimate that the average export of Cs-137 in surface water over the 10-yr interval was < 0.6% yr(-1). For lakes and reservoirs with low rates of radionuclide export, hundreds to thousands of sediment cores may be required to detect changes in radionuclide inventories beyond radioactive decay over time spans less than several decades. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Lewis, GP (reprint author), Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. NR 22 TC 2 Z9 2 U1 0 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 2000 VL 49 IS 3 BP 293 EP 306 DI 10.1016/S0265-931X(99)00127-7 PG 14 WC Environmental Sciences SC Environmental Sciences & Ecology GA 305BA UT WOS:000086517900005 ER PT J AU Adriano, DC Doswell, AC Ciravolo, TG Pinder, JE McLeod, KW AF Adriano, DC Doswell, AC Ciravolo, TG Pinder, JE McLeod, KW TI Radionuclide content of selected root vegetables as influenced by culinary preparation SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Article DE radionuclides; vegetables; culinary preparation; scrubbing; peeling; radiocesium; strontium; plutonium ID TIME-DEPENDENT TRANSFER; CONTRASTING SOIL TYPES; 5-YEAR LYSIMETER; CROPS; CS-137; PU-239; AM-241; SR-90 AB A greenhouse study involving root vegetables (carrot, red beet, and turnips) was conducted primarily to evaluate the effect of culinary processing (light washing, scrubbing, and peeling) on the radionuclide content of the edible portions. In terms of concentration ratio of the radionuclides left in roots after peeling, the trend follows: Sr-90 > (137) Cs much greater than U-234 congruent to U-238 greater than or equal to Pu-238. The actinide contents in the roots were apparently due to surface adherence of the contaminated soil particulates as indicated by the diminution of the contents upon brushing the surface, which were further decreased by peeling the skin. Rigorous culinary processing of roots, such as scrubbing or peeling, could substantially diminish the contents of the actinides, but not of the more mobile Sr-90 and Cs-137. (C) 2000 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. US Dept Energy, Savannah River Operat Off, SRS, Aiken, SC 29802 USA. RP Adriano, DC (reprint author), Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. NR 26 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 2000 VL 49 IS 3 BP 307 EP 317 PG 11 WC Environmental Sciences SC Environmental Sciences & Ecology GA 305BA UT WOS:000086517900006 ER PT J AU Shor, JT Dial, C AF Shor, JT Dial, C TI Volatilization of cobalt, technetium, and uranium isotopes from soils through salt amendment and calcination SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Article DE decontamination; volatilization; salt amendment; calcination soils AB The effects of alkali and alkaline earth metal chloride salts on the decontamination (through volatilization) of radionuclides from clay soils in a calcination process were examined. Calcium chloride was found to decontaminate Co-60-containing soils to a maximum ext ent of about 65 % of Co-60 present before treatment by calcination for 8 h at 1000 degrees C with the addition of about 4 milliequivalents (meq) of chloride per gram of soil. Repeated calcination treatments raised the level of decontamination to 80%, but not beyond. Technetium could be removed from clay soils slightly more effectively using a similar salting and calcination process. No decontamination of strontium or uranium soils was found using this process under reducing or oxidizing conditions. The data presented indicate areas in which the presence of chlorides may result in problems in the thermal treatment of soils or similar matrices; however, no viable decontamination process was achieved. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Shor, JT (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 8 TC 1 Z9 1 U1 1 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 2000 VL 48 IS 1 BP 35 EP 48 DI 10.1016/S0265-931X(99)00051-X PG 14 WC Environmental Sciences SC Environmental Sciences & Ecology GA 280TQ UT WOS:000085120200004 ER PT J AU Tiller, BL Poston, TM AF Tiller, BL Poston, TM TI Mule deer antlers as biomonitors of strontium-90 on the Hanford Site SO JOURNAL OF ENVIRONMENTAL RADIOACTIVITY LA English DT Article ID HOME-RANGE; SR-90 AB This study evaluated deer antlers as indicators of animal uptake of localized Sr-90 contamination on the Hanford Site in south-central Washington. Levels of Sr-90 were examined in 38 mule deer (Odocoileus hemionus hemionus) antler samples collected near and distant from previously active nuclear reactor facilities and from a reference site in central Oregon. Results showed that Sr-90 concentrations in antlers collected near reactor facilities were significantly higher (P < 0.001) than other Hanford samples. Reference samples contained nearly 5 times the levels of Sr-90 compared with Hanford. Strontium-90 concentrations in deer antlers collected at the reference locations were higher than Hanford site deer, presumably because the deer inhabited mountain regions during the summer months that received more atmospheric fallout from historic weapons testing. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Tiller, BL (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 44 TC 9 Z9 9 U1 1 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0265-931X J9 J ENVIRON RADIOACTIV JI J. Environ. Radioact. PY 2000 VL 47 IS 1 BP 29 EP 44 PG 16 WC Environmental Sciences SC Environmental Sciences & Ecology GA 236HM UT WOS:000082594200003 ER PT J AU Nakamura, T Senior, CL Burns, EG Bell, MD AF Nakamura, T Senior, CL Burns, EG Bell, MD TI Solar-powered soil vapor extraction for removal of dense nonaqueous phase organics from soil SO JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING LA English DT Article DE soil vapor extraction; remediation; DNAPL AB Both surface and groundwater are threatened by buried waste at a number of sites because of subsurface plumes containing dense non-aqueous phase liquids (DNAPLs), hazardous metals, and radionuclides. In this work, a novel process is explored which represents an enhancement to thermal extraction methods as well as a mobile system that is suitable for remediation of remote sites. Solar radiation is collected by modular concentrators which transfer the concentrated solar radiation to an optical waveguide (OW) transmission line consisting of low-loss optical fibers. The OW line transmits the high intensity solar radiation to the contaminated site where the solar flux is injected into the soil for thermally enhanced soil vapor extraction (SVE). The organic compounds driven out of the soil go through off-gas treatment. A small prototype was constructed and used to heat soil contaminated with trichloroethylene (TCE). The thermal efficiency of the solar SVE process conducted using the small scale experiment was approximately 50%. The moisture loss in the soil sample correlated to the soil heating time. Short heating times were sufficient to remove TCE from soil samples below detection limits. C1 Phys Sci Inc, San Ramon, CA USA. Phys Sci Inc, Andover, MA USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Nakamura, T (reprint author), Phys Sci Inc, San Ramon, CA USA. NR 12 TC 4 Z9 4 U1 1 U2 1 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 1093-4529 J9 J ENVIRON SCI HEAL A JI J. Environ. Sci. Health Part A-Toxic/Hazard. Subst. Environ. Eng. PY 2000 VL 35 IS 6 BP 795 EP 816 PG 22 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 327MV UT WOS:000087798400001 ER PT J AU Roh, Y Lee, SY Elless, MP Cho, KS AF Roh, Y Lee, SY Elless, MP Cho, KS TI Electro-enhanced remediation of radionuclide-contaminated groundwater using zero-valent iron SO JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING LA English DT Article DE electroremdiation; water treatment; uranium; technetium; zero-valent iron AB The objective of this study was to develop and evaluate electrochemically-enhanced immobilization of radionuclides in contaminated groundwater using Fe-0. A bench-scale flow-through Fe-0 reactor column with direct current was tested to increase the efficiency and effective life of the Fe-0 medium by (i) providing an external supply of electrons, (ii) controlling the rate of iron oxidation, and (iii) enhancing the rate of radionuclide immobilization. The removal mechanism appears to be reductive coprecipitation of radionuclides by iron oxidation by creating a reducing environment in the reactive iron barrier. Several factors influence the removal of radionuclides from groundwater using this reactor column including electrode configuration, applied voltage, distance between cathode and anode, and radionuclide concentration. C1 Univ Tennessee, Dept Plant & Soil Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Edenspace Syst Corp, Reston, VA 20191 USA. Chonbuk Natl Univ, Dept Earth Sci Educ, Chonju, South Korea. RP Roh, Y (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 13 TC 14 Z9 14 U1 1 U2 10 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 1093-4529 J9 J ENVIRON SCI HEAL A JI J. Environ. Sci. Health Part A-Toxic/Hazard. Subst. Environ. Eng. PY 2000 VL 35 IS 7 BP 1043 EP 1059 PG 17 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 341RA UT WOS:000088602300005 ER PT J AU Roh, Y Lee, SY Elless, MP Moon, HS AF Roh, Y Lee, SY Elless, MP Moon, HS TI Electro-enhanced remediation of trichloroethene-contaminated groundwater using zero-valent iron SO JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING LA English DT Article DE electroremdiation; water treatment; trichloroethene; zero-valent iron ID REDUCTIVE DEHALOGENATION; CHLORINATED ETHYLENES AB The objective of this study was to develop and evaluate electro-enhanced dechlorination of trichloroethene (TCE) in groundwater using Fe-0. A bench-scale flow-through Fe-0 reactor column with direct current was tested to increase the efficiency of Fe-0 medium by providing an external supply of electrons. The bench-scale column tests confirmed that the application of direct current with Fe-0 was highly effective in enhancing the rate of TCE dechlorination. The t(1/2) for the TCE dechlorination without current was 10.3 hours and the t(1/2) for the TCE dechlorination with current was about 1 hour. The dechlorination mechanism appears to be reductive dechlorination, with the electrons supplied by the iron oxidation and external direct current power supply serving as the source of the electrons. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Plant & Soil Sci, Knoxville, TN 37996 USA. Edenspace Syst Corp, Reston, VA 20191 USA. Yonsei Univ, Dept Earth Syst Sci, Seoul 120749, South Korea. RP Roh, Y (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 11 TC 12 Z9 12 U1 1 U2 1 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 1093-4529 J9 J ENVIRON SCI HEAL A JI J. Environ. Sci. Health Part A-Toxic/Hazard. Subst. Environ. Eng. PY 2000 VL 35 IS 7 BP 1061 EP 1076 PG 16 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 341RA UT WOS:000088602300006 ER PT J AU Fresquez, PR Huchton, JD Mullen, MA Naranjo, L AF Fresquez, PR Huchton, JD Mullen, MA Naranjo, L TI Radionuclides in pinon pine (Pinus edulis) nuts from Los Alamos National Laboratory lands and the dose from consumption SO JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART B-PESTICIDES FOOD CONTAMINANTS AND AGRICULTURAL WASTES LA English DT Article DE Pu; Cs; Sr; Am; U; contamination; translocation; exposure; risk ID SOILS AB One of the dominant tree species growing within and around the eastern portion of Los Alamos National Laboratory (LANL), Los Alamos, NM, lands is the pinon pine (Pinus edulis). Pinon pine is used for firewood, fence posts, and building materials and is a source of nuts for food-the seeds are consumed by a wide variety of animals and are also gathered by people in the area and eaten raw or roasted. This study investigated the (1) concentration of H-3, Cs-137, Sr-90, U-tot, Pu-238, Pu-239,Pu-240, and Am-241 in soils (0- to 12-in. [31 cm] depth underneath the tree), pinon pine shoots (PPS), and pinon pine nuts (PPN) collected from LANL lands and regional background (BG) locations, (2) committed effective dose equivalent (CEDE) from the ingestion of nuts, and (3) soil to PPS to PPN concentration ratios (CRs). Most radionuclides, with the exception of 3H in soils, were not significantly higher (p < 0.10) in soils, PPS, and PPN collected from LANL as compared to BG locations, and concentrations of most radionuclides in PPN from LANL have decreased over time. The maximum net CEDE (the CEDE plus two sigma minus BG) at the most conservative ingestion rate (10 Ib [4.5 kg]) was 0.0018 mrem (0.018 mu Sv); this is far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem (1000 mu SV). Soil-to-nut CRs for most radionuclides were within the range of default values in the literature for common fruits and vegetables. C1 Univ Calif Los Alamos Natl Lab, Environm Safety & Hlth Div, Los Alamos, NM 87545 USA. RP Fresquez, PR (reprint author), Univ Calif Los Alamos Natl Lab, Environm Safety & Hlth Div, M887, Los Alamos, NM 87545 USA. NR 20 TC 0 Z9 0 U1 0 U2 3 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0360-1234 J9 J ENVIRON SCI HEAL B JI J. Environ. Sci. Health Part B-Pestic. Contam. Agric. Wastes PY 2000 VL 35 IS 5 BP 611 EP 622 DI 10.1080/03601230009373296 PG 12 WC Environmental Sciences; Public, Environmental & Occupational Health SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health GA 348HP UT WOS:000088979700007 PM 10968611 ER PT J AU Maskarinec, MP Jenkins, RA Counts, RW Dindal, AB AF Maskarinec, MP Jenkins, RA Counts, RW Dindal, AB TI Determination of exposure to environmental tobacco smoke in restaurant and tavern workers in one US city SO JOURNAL OF EXPOSURE ANALYSIS AND ENVIRONMENTAL EPIDEMIOLOGY LA English DT Article DE area sampling; bars and restaurants; bartenders; cotinine; environmental tobacco smoke; exposure; hospitality workers; Knoxville SMSA; nicotine; personal monitoring; RSP; second hand smoke; solanesol; waiters and waitresses; 3-Ethylene pyridine ID INDOOR ENVIRONMENTS; NICOTINE; COTININE; BARS; AIR AB Approximately 173 subjects employed as waiters, waitresses, or bartenders in the Knoxville, TN, Standard Metropolitan Statistical Area collected a sample of air from their breathing zone while at their workplace for one shift. In addition, area samples were placed near the work spaces of many of the subjects. Collected samples were analyzed for respirable suspended particulate matter (RSPM), ultraviolet-absorbing and fluorescing particulate matter, solanesol, 3-ethenylpyridine (3-EP), and nicotine. Saliva samples were collected from the subjects prior to and within 24 h following their work shift, to confirm their non-smoking status. The range of concentrations of environmental tobacco smoke (ETS) constituents encountered was considerable, e.g., for nicotine, from undetectable to more than 100 mu g/m(3). However, the highest RSP levels observed were considerably lower than OSHA workplace standards. Distributions of ETS concentrations suggest that there are two "ETS exposure" types of bartenders: those that work in single room bars and those that work in larger, multi room restaurant/bars. Personal exposure to ETS of the former group was ca. 10x greater than those of the latter group, who were exposed to ETS levels more comparable to those encountered by wait staff. Exposure (concentration x duration) differences between wait staff and workers in other types of unrestricted smoking environments reported in other studies suggest that exposures in the restaurant environment may be more difficult to assess than originally considered. Salivary cotinine levels indicated that for those subjects living in smoking homes, ETS exposures outside the workplace are at least as important as those in the workplace. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Maskarinec, MP (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Mail Stop 6120,Bldg 2008,POB 2008, Oak Ridge, TN 37831 USA. NR 27 TC 50 Z9 50 U1 2 U2 4 PU NATURE PUBLISHING GROUP PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 1053-4245 J9 J EXPO ANAL ENV EPID JI J. Expo. Anal. Environ. Epidemiol. PD JAN-FEB PY 2000 VL 10 IS 1 BP 36 EP 49 DI 10.1038/sj.jea.7500069 PG 14 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 327RM UT WOS:000087806600004 PM 10703846 ER PT J AU Del Cul, GD Trowbridge, LD Toth, LM Fiedor, JN AF Del Cul, GD Trowbridge, LD Toth, LM Fiedor, JN TI Some investigations of the reaction of activated charcoal with fluorine and uranium hexafluoride SO JOURNAL OF FLUORINE CHEMISTRY LA English DT Article DE activated charcoal; carbon fluoride; uranium fluorides; oxyfluorides ID F-19; C-13 AB Since the 1969 shutdown of the Molten Salt Reactor Experiment (MSRE) at Oak Ridge, radiolytically generated fluorine (F-2) and 233-uranium hexafluoride ((UF6)-U-233) migrated from the fuel storage tanks through gas piping to a charcoal bed. This report addresses the carbon-fluorine-uranium chemistry under conditions reproducing those found in the charcoal beds. Laboratory analysis of the reaction products has been extensive and includes electron spectroscopy for chemical analysis (ESCA), nuclear magnetic resonance (NMR), FTIR and Raman spectroscopy, TGA-DTA as well as a host of other techniques. The chemical identity, stoichiometry, structure, thermochemistry, and potential for energetic decomposition of the primary reaction product, 'fluorinated charcoal', was determined. As a result of this research, remedial solutions were developed and implemented. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Adv Integrated Management Serv Inc, Oak Ridge, TN 37830 USA. Bechtel bettis Inc, W Mifflin, PA 15122 USA. RP Del Cul, GD (reprint author), Oak Ridge Natl Lab, 1 Bethel Valley Rd, Oak Ridge, TN 37831 USA. NR 37 TC 5 Z9 5 U1 1 U2 9 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-1139 J9 J FLUORINE CHEM JI J. Fluor. Chem. PD JAN PY 2000 VL 101 IS 1 BP 137 EP 148 DI 10.1016/S0022-1139(99)00250-X PG 12 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 269RY UT WOS:000084492400024 ER PT J AU Morin, RH Descamps, GE Cecil, LD AF Morin, RH Descamps, GE Cecil, LD TI Acoustic televiewer logging in glacier boreholes SO JOURNAL OF GLACIOLOGY LA English DT Article ID STORGLACIAREN; SWEDEN; ICE AB The acoustic televiewer is a geophysical logging instrument that is deployed in a water-filled borehole and operated while trolling It generates a digital, magnetically oriented image of the borehole wall that is developed from the amplitudes and transit times of acoustic waves emitted from the tool and reflected at the water-wall interface. The transit-time data are also converted to radial distances, from which cross-sectional views of the borehole shape can be constructed. Because the televiewer is equipped with both a three-component magnetometer and a two-component inclinometer, the borehole's trajectory in space is continuously recorded as well. This instrument is routinely used in mining and hydrogeologic applications, but in this investigation it was deployed in two boreholes drilled into Upper Fremont Glacier, Wyoming, U.S.A. The acoustic images recorded in this glacial setting are not as clear as those typically obtained in rocks, due to a lower reflection coefficient for water and ice than for water and rock. Results indicate that the depth and orientation of features intersecting the boreholes can be determined, but that interpreting their physical nature is problematic and requires corroborating information from inspection of cores. Nevertheless, these data can provide some insight into englacial structural characteristics. Additional information derived from the cross-sectional geometry of the borehole, as well as from its trajectory, may also be useful in studies concerned with stress patterns and deformation processes. C1 US Geol Survey, Denver, CO 80225 USA. Univ Laval, Quebec City, PQ G1K 7P4, Canada. US Geol Survey, Idaho Falls, ID 83402 USA. RP Morin, RH (reprint author), US Geol Survey, Box 25046, Denver, CO 80225 USA. NR 14 TC 0 Z9 0 U1 1 U2 1 PU INT GLACIOL SOC PI CAMBRIDGE PA LENSFIELD RD, CAMBRIDGE CB2 1ER, ENGLAND SN 0022-1430 J9 J GLACIOL JI J. Glaciol. PY 2000 VL 46 IS 155 BP 695 EP 699 DI 10.3189/172756500781832684 PG 5 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 401QA UT WOS:000166938600015 ER PT J AU Brettin, TS Karle, R Crowe, EL Lezzoni, AF AF Brettin, TS Karle, R Crowe, EL Lezzoni, AF TI Chloroplast inheritance and DNA variation in sweet, sour, and ground cherry SO JOURNAL OF HEREDITY LA English DT Article ID BIPARENTAL INHERITANCE; PATERNAL INHERITANCE; MEDICAGO-SATIVA; PRUNUS-CERASUS; PLASTIDS; AMPLIFICATION; EVOLUTION; GENES; MAP C1 Michigan State Univ, Dept Hort, E Lansing, MI 48824 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Lezzoni, AF (reprint author), Michigan State Univ, Dept Hort, E Lansing, MI 48824 USA. NR 22 TC 32 Z9 33 U1 0 U2 1 PU OXFORD UNIV PRESS INC PI CARY PA JOURNALS DEPT, 2001 EVANS RD, CARY, NC 27513 USA SN 0022-1503 J9 J HERED JI J. Hered. PD JAN-FEB PY 2000 VL 91 IS 1 BP 75 EP 79 DI 10.1093/jhered/91.1.75 PG 5 WC Evolutionary Biology; Genetics & Heredity SC Evolutionary Biology; Genetics & Heredity GA 280KM UT WOS:000085102000017 PM 10739133 ER PT J AU Bern, Z Dixon, L Kosower, DA AF Bern, Z Dixon, L Kosower, DA TI A two-loop four-gluon helicity amplitude in QCD SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE QCD; NLO computations; jets ID TO-LEADING ORDER; YANG-MILLS THEORY; GAUGE-THEORY; DIMENSIONAL REGULARIZATION; INFRARED BEHAVIOR; COLLINEAR LIMITS; PERTURBATIVE QCD; CROSS-SECTIONS; UNITARITY; GRAVITY AB We present the two-loop pure gauge contribution to the gluon-gluon scattering amplitude with maximal helicity violation. Our construction of the amplitude does not rely directly on Feynman diagrams, but instead uses its analytic properties in 4 - 2 epsilon dimensions. We evaluate the loop integrals appearing in the amplitude through O(epsilon (0)) in terms of polylogarithms. C1 Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Ctr Etud Saclay, Serv Phys Theor, Commiss Energie Atom France, Direct Sci Mat Lab, F-91191 Gif Sur Yvette, France. RP Bern, Z (reprint author), Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. EM bern@physics.ucla.edu; lance@slac.stanford.edu; kosower@spht.saclay.cea.fr NR 45 TC 130 Z9 130 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD JAN PY 2000 IS 1 AR 027 PG 30 WC Physics, Particles & Fields SC Physics GA 456DW UT WOS:000170068700027 ER PT J AU Blum, JD AF Blum, JD TI Supersymmetric quantum mechanical description of four dimensional black holes SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE black holes in string theory; M(atrix) theories ID CALOGERO-MOSER SYSTEM; BOUND-STATES; D-BRANES; P-BRANES; STRINGS; THRESHOLD; SPECTRUM; MODELS AB By assuming the existence of a novel multipronged string state for D-particles interacting with D-brane intersections in type-IIA string theory, we are able to derive a quantum mechanical description of supersymmetric Reissner-Nordstrom black holes. A supersymmetric index calculation provides evidence for this conjecture. The quantum mechanical system becomes two decoupled conformal quantum mechanical systems in the low energy limit. The conformal quantum mechanics has expected properties of a dual description of string theory on AdS(2) x S-2. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Blum, JD (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Theoret Phys Grp, Mail Stop 50A-5101, Berkeley, CA 94720 USA. EM julie@thsrv.lbl.gov NR 47 TC 23 Z9 23 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD JAN PY 2000 IS 1 AR 006 PG 30 WC Physics, Particles & Fields SC Physics GA 456DW UT WOS:000170068700006 ER PT J AU Detours, V Mehr, R Perelson, AS AF Detours, V Mehr, R Perelson, AS TI Deriving quantitative constraints on T cell selection from data on the mature T cell repertoire SO JOURNAL OF IMMUNOLOGY LA English DT Article ID SINGLE MHC/PEPTIDE LIGAND; CLASS-II MHC; POSITIVE SELECTION; THYMIC SELECTION; LYMPHOCYTIC CHORIOMENINGITIS; 3-DIMENSIONAL STRUCTURE; ANTIBODY REPERTOIRE; NEGATIVE SELECTION; RECEPTOR STRUCTURE; ALLELIC EXCLUSION AB The T cell repertoire is shaped in the thymus through positive and negative selection. Thus, data about the mature repertoire may be used to infer information on how TCR generation and selection operate. Assuming that T cell selection is affinity driven, we derive the quantitative constraints that the parameters driving these processes must fulfill to account for the experimentally observed levels of alloreactivity, self MHC restriction and the frequency of cells recognizing a given foreign Ag, We find that affinity-driven selection is compatible with experimental estimates of these latter quantities only if 1) TCRs see more peptide residues than MHC polymorphic residues, 2) the majority of positively selected clones are deleted by negative selection, 3) between 1 and 3.6 clonal divisions occur on average in the thymus after completion of TCR rearrangement, and 4) selection is driven by 10(3)-10(5) self peptides. C1 Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Santa Fe Inst, Santa Fe, NM 87501 USA. Princeton Univ, Dept Mol Biol, Princeton, NJ 08544 USA. RP Perelson, AS (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, MS K710, Los Alamos, NM 87545 USA. FU NCRR NIH HHS [RR06555]; NIAID NIH HHS [AI28433]; NIGMS NIH HHS [GM20964-25] NR 78 TC 20 Z9 20 U1 0 U2 0 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD JAN 1 PY 2000 VL 164 IS 1 BP 121 EP 128 PG 8 WC Immunology SC Immunology GA 266VP UT WOS:000084321200020 PM 10605002 ER PT J AU Haverlock, TJ Bonnesen, PV Sachleben, RA Moyer, BA AF Haverlock, TJ Bonnesen, PV Sachleben, RA Moyer, BA TI Analysis of equilibria in the extraction of cesium nitrate by calix[4]arene-bis(t-octylbenzo-crown-6) in 1,2-dichloroethane SO JOURNAL OF INCLUSION PHENOMENA AND MACROCYCLIC CHEMISTRY LA English DT Article DE Calixarene-crown ether; Cs(+) complexation; solvent extraction; SXLSQI; equilibrium constants; partition ratio; modeling ID SUPPORTED LIQUID MEMBRANES; 1,3-ALTERNATE CONFORMATION; SOLVENT-EXTRACTION; CRYSTAL-STRUCTURES; CROWN; CATIONS; ETHERS; CALIX<4>-BIS-CROWNS; COMPLEXATION; ANIONS AB The extraction of CsNO(3) by the highly lipophilic calixarene-crown ether calix[4]arene-bis(t-octylbenzo-crown-6) (CABOBC6) in 1,2-dichloroethane (1,2-DCE) at 25 degrees C has been shown to be consistent with the formation of both 1 : 1 and 2 : 1 metal : ligand species. Variation of the aqueous-phase CsNO(3) concentration up to 1.0 M and variation of the organic-phase calixarene concentration up to 0.10 M was modeled by the program SXLSQI. Formation of the organic-phase species CsBNO(3) (B = calixarene) was confirmed as well as the organic-phase dissociation products CsB(+) and NO(3)(-). Good evidence for the 2 : 1 metal : ligand organic-phase species Cs(2)B(NO(3))(2) was also found, although the dissociation of nitrate from this complex was not observed. Binding of the second Cs(+) cation by the ligand is approximately two orders of magnitude weaker than binding of the first Cs(+) cation. The logarithm of the apparent partition ratio (log P(B)) of the calixarene between water and 1,2-DCE was found by (1)H-NMR techniques to be > 5.1. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Moyer, BA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Solominow, Sonia/A-4021-2008; Bonnesen, Peter/A-1889-2016; Moyer, Bruce/L-2744-2016 OI Bonnesen, Peter/0000-0002-1397-8281; Moyer, Bruce/0000-0001-7484-6277 NR 36 TC 69 Z9 69 U1 1 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0923-0750 J9 J INCL PHENOM MACRO JI J. Incl. Phenom. Macrocycl. Chem. PY 2000 VL 36 IS 1 BP 21 EP 37 DI 10.1023/A:1008084531647 PG 17 WC Chemistry, Multidisciplinary SC Chemistry GA 275PK UT WOS:000084828400003 ER PT J AU Hambaba, A AF Hambaba, A TI Robust hybrid architecture to signals from manufacturing and machine monitoring sensors SO JOURNAL OF INTELLIGENT & FUZZY SYSTEMS LA English DT Article ID NEURAL NETWORKS AB The design and implementation of effective control of manufacturing processes depends on the successful monitoring and recognition of process signals. In this paper, we describe an application of robust hybrid model to the prediction of plasma etcher outcome; etcher rate, selectivity, and uniformity. The robust hybrid model consists of two main architectures: robust model and recurrent neural network with real-time recurrent learning. The residual errors are used for the tuning of the weights of the recurrent neural network. The robust hybrid model's performance is compared to Ordinary Least-Square method, Alpha-trimmed mean, and Back-Propagation neural network. C1 NASA, Ames Res Ctr, NRC, Ames, IA USA. San Jose State Univ, Comp Informat & Syst Engn Dept, San Jose, CA 95192 USA. RP Hambaba, A (reprint author), NASA, Ames Res Ctr, NRC, Ames, IA USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1064-1246 J9 J INTELL FUZZY SYST JI J. Intell. Fuzzy Syst. PY 2000 VL 9 IS 1-2 BP 29 EP 41 PG 13 WC Computer Science, Artificial Intelligence SC Computer Science GA 391GK UT WOS:000166348100003 ER PT J AU Zhang, Y Ge, WK AF Zhang, Y Ge, WK TI Behavior of nitrogen impurities in III-V semiconductors SO JOURNAL OF LUMINESCENCE LA English DT Article DE isoelectric impurity; bound exciton; electron-phonon interaction; GaP : N; GaAs : N ID ISOELECTRONIC IMPURITIES; GAP1-XNX ALLOYS; BOUND EXCITONS; GAASN ALLOYS; GAP; PAIRS; BAND; PHOTOLUMINESCENCE; LUMINESCENCE; MODEL AB A detailed review on a few important issues related to the isoelectronic impurity nitrogen in III-V semiconductors GaP and GaAs ape given in this article. These issues include (1) the binding mechanism for the nitrogen bound exciton, (2) the electron binding energy calculation, (3) the exciton binding energy calculation, (4) the exciton-phonon coupling, and (5) the behavior of the nitrogen in dilute nitride alloys. We conclude that a key problem that remains not well answered is the interplay of the short-range impurity potential originated from the atomic energy difference, the strain field caused by the lattice relaxation and the accompanying electronic polarization. The solution to this problem is essential to solve the long-standing mystery: what exactly are those pair's configurations? (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Hong Kong Univ Sci & Technol, Dept Phys, Kowloon, Hong Kong, Peoples R China. RP Zhang, Y (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 72 TC 34 Z9 40 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2313 J9 J LUMIN JI J. Lumines. PD JAN PY 2000 VL 85 IS 4 BP 247 EP 260 DI 10.1016/S0022-2313(99)00193-3 PG 14 WC Optics SC Optics GA 283CR UT WOS:000085259000012 ER PT J AU Bruce, JE Anderson, GA Lin, CY Gorshkov, M Rockwood, AL Smith, RD AF Bruce, JE Anderson, GA Lin, CY Gorshkov, M Rockwood, AL Smith, RD TI A novel high-performance Fourier transform ion cyclotron resonance cell for improved biopolymer characterization SO JOURNAL OF MASS SPECTROMETRY LA English DT Article DE ion trap; electric field; quadrupolar; SIMION; frequency shift; biopolymers ID MOLECULAR-WEIGHT DETERMINATION; FTICR MASS-SPECTROMETRY; INDIVIDUAL IONS; EXCITATION; TRAP; RESOLUTION; ELECTRODE; REMEASUREMENT; AXIALIZATION; PROTEINS AB A new trapped ion cell design for use with Fourier transform ion cyclotron resonance mass spectrometry is described. The design employs 15 cylindrical ring electrodes to generate trapping potential wells and 32 separately assignable rod electrodes for excitation and detection. The rod electrodes are positioned internal to the ring electrodes and provide excitation fields that are thereby linearized along the magnetic field over the entire trapped ion volume. The new design also affords flexibility in the shaping of the trapping field using the 15 ring electrodes. Many different trapping well shapes can be generated by applying different voltages to the individual ring electrodes, ranging from quadratic to linearly ramped along the magnetic field axis, to a shape that is nearly flat over the entire trap volume, but rises very steeply near the ends of the trap. This feature should be useful for trapping larger ion populations and extension of the useful range of ion manipulation and dissociation experiments since the number of stages of ion manipulation or dissociation is limited in practice by the initial trapped ion population size. Predicted trapping well shapes for two different ring electrode configurations are presented, and these and several other possible configurations are discussed, as are the predicted excitation fields based on the use of rod electrodes internal to the trapping ring electrodes. Initial results are presented from an implementation of the design using a 3.5 T superconducting magnet. It was found that ions can be successfully trapped and detected with this cell design and that selected ion accumulation ran be performed with the utilization of four rods for quadrupolar excitation. The initial results presented here illustrate the feasibility of this cell design and demonstrate differences in observed performance based upon different trapping well shapes. Copyright (C) 2000 John Wiley & Sons, Ltd. C1 Pacific NW Lab, Macromol Struct & Dynam Grp, Environm & Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Lab, Macromol Struct & Dynam Grp, Environm & Mol Sci Lab, POB 999, Richland, WA 99352 USA. RI Gorshkov, Mikhail/E-8522-2010; Smith, Richard/J-3664-2012; Gorshkov, Mikhail/N-4984-2013 OI Smith, Richard/0000-0002-2381-2349; Gorshkov, Mikhail/0000-0001-9572-3452 FU NCRR NIH HHS [RR12365] NR 50 TC 21 Z9 22 U1 0 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1076-5174 J9 J MASS SPECTROM JI J. Mass Spectrom. PD JAN PY 2000 VL 35 IS 1 BP 85 EP 94 DI 10.1002/(SICI)1096-9888(200001)35:1<85::AID-JMS910>3.3.CO;2-Z PG 10 WC Biophysics; Chemistry, Organic; Spectroscopy SC Biophysics; Chemistry; Spectroscopy GA 277ZV UT WOS:000084964200010 PM 10633238 ER PT J AU Brown, MJ Hillman, AR Martin, SJ Cernosek, RW Bandey, HL AF Brown, MJ Hillman, AR Martin, SJ Cernosek, RW Bandey, HL TI Manipulation of electroactive polymer film viscoelasticity: the roles of applied potential and frequency SO JOURNAL OF MATERIALS CHEMISTRY LA English DT Article ID QUARTZ-CRYSTAL RESONATOR; EMPLOYING CONDUCTING POLYMERS; ELECTROCHEMICAL DEPOSITION; POLYTHIOPHENE FILMS; POLYBITHIOPHENE FILMS; CYCLIC VOLTAMMETRY; IMPEDANCE ANALYSIS; SHEAR MODULUS; THIN-FILMS; MICROBALANCE AB We describe quartz crystal impedance measurements on thin films of poly(3-hexylthiophene) (PHT) electrochemically maintained at different potentials and exposed to propylene carbonate electrolyte solutions. Film shear modulus values, obtained at fixed potentials corresponding to a range of film oxidation states ("doping levels"), show a marked variation of storage and loss moduli (G' and G ", respectively). The p-doped film is substantially softer than the undoped film, and G' and G " can show maxima at partial p-doping. Even in nominally "equilibrium" experiments (at fixed potential) there is dramatic hysteresis in shear modulus values determined during stepwise doping and undoping. This general pattern of behaviour is observed at a range of frequencies, corresponding to the fundamental frequency (10 MHz) and higher harmonics (30 MHz to 110 MHz). There are substantial increases in shear modulus with increasing frequency for all doping levels, and the loss tangent (G "/G') is frequency dependent. A Voigt model is qualitatively incompatible with these observations, and a Maxwell model can qualitatively explain some features; more sophisticated models are required to provide quantitative explanations. We discuss these observations in terms of potential-driven film ion and solvent population changes. The data are consistent with non-equilibrium film solvent populations for intermediate doping levels, even though the equilibrium ion populations (charge states) may be established. Together, selection of operating frequency, applied potential and time scale offer the prospect of manipulating film viscoelastic parameters in a controllable manner over several orders of magnitude, from "rubbery" to near "glassy" behaviour. C1 Univ Leicester, Dept Chem, Leicester LE1 7RH, Leics, England. Sandia Natl Labs, Microsensor Res Div, Albuquerque, NM 87185 USA. RP Hillman, AR (reprint author), Univ Leicester, Dept Chem, Leicester LE1 7RH, Leics, England. EM arh7@le.ac.uk OI Hillman, Robert/0000-0003-1868-5717 NR 67 TC 26 Z9 26 U1 1 U2 5 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0959-9428 J9 J MATER CHEM JI J. Mater. Chem. PY 2000 VL 10 IS 1 BP 115 EP 126 PG 12 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 267BK UT WOS:000084334600014 ER PT J AU Minervini, L Grimes, RW Kilner, JA Sickafus, KE AF Minervini, L Grimes, RW Kilner, JA Sickafus, KE TI Oxygen migration in La2NiO4+delta SO JOURNAL OF MATERIALS CHEMISTRY LA English DT Article ID DEFECT; SUPERCONDUCTIVITY; LA2CUO4; OXIDES; DIFFRACTION; TRANSPORT; BEHAVIOR; CERAMICS; PHASES AB Atomic scale computer simulation based on energy minimization techniques has been used to study excess oxygen accommodation and migration in La2NiO4+delta. The activation energy for migration in the ac plane is predicted to be 0.29 eV, while the activation energy outside the ac plane, in the b direction is predicted to be 2.90 eV. The activation energies within the ac plane are unaffected by the presence of compensating Ni3+ defects. C1 Univ London Imperial Coll Sci Technol & Med, Dept Mat, London SW7 2BP, England. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87454 USA. RP Grimes, RW (reprint author), Univ London Imperial Coll Sci Technol & Med, Dept Mat, London SW7 2BP, England. NR 49 TC 136 Z9 137 U1 4 U2 40 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0959-9428 J9 J MATER CHEM JI J. Mater. Chem. PY 2000 VL 10 IS 10 BP 2349 EP 2354 DI 10.1039/b004212i PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 354YX UT WOS:000089359800027 ER PT J AU Tartaj, P De Jonghe, LC AF Tartaj, P De Jonghe, LC TI Preparation of nanospherical amorphous zircon powders by a microemulsion-mediated process SO JOURNAL OF MATERIALS CHEMISTRY LA English DT Article ID SOL-GEL PROCESS; SILICA PARTICLES; ZRO2-SIO2; ZRSIO4; AEROSOLS; CRYSTALLIZATION; HYDROLYSIS; GLASSES; OXIDES; SYSTEM AB A modified reverse micelle process has been developed for the synthesis of nanospherical amorphous zircon precursor powders. It has been found that the hydrolysis of a mixture of zirconium and silicon alkoxides within the water phase of a microemulsion can produce amorphous, nanospherical particles with a stoichiometric ZrSiO4 composition. Microemulsions were obtained by using cyclohexane as the oil phase, ammonium solutions as the aqueous phase, and Igepal Co520 as surfactant. Precise control of the stoichiometry of the powders was achieved after the starting silicon and zirconium alkoxides were appropriately modified. In particular, silicon alkoxide was pre-hydrolyzed under acidic conditions while zirconium alkoxide was reacted with chelating agents. The as-prepared powders consisted of amorphous nanospherical particles with compositional homogeneity. Heating of powders led first to incipient tetragonal zirconia crystallization at a temperature of 900 degreesC. The onset of crystalline zircon formation was detected at 1200 degreesC, while the conversion was complete after heating the amorphous precursor powders at 1300 degreesC for 2 hours. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. RP De Jonghe, LC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RI Tartaj, Pedro/B-8983-2008 OI Tartaj, Pedro/0000-0001-7323-1545 NR 44 TC 27 Z9 28 U1 1 U2 9 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0959-9428 J9 J MATER CHEM JI J. Mater. Chem. PY 2000 VL 10 IS 12 BP 2786 EP 2790 DI 10.1039/b002720k PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 376ZQ UT WOS:000165487800032 ER PT J AU Wang, JG Zhang, LC Chen, GL Ye, HQ AF Wang, JG Zhang, LC Chen, GL Ye, HQ TI Study on the alpha(2)/gamma interfacial structures in a two-phase (alpha(2)+gamma) alloy deformed at elevated temperature SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID TRANSMISSION ELECTRON-MICROSCOPY; GAMMA-TITANIUM ALUMINIDES; TI-45AL-10NB ALLOY; INTERMETALLIC ALLOYS; MECHANICAL TWINS; BOUNDARIES; DISLOCATIONS; DEFORMATION; TI3AL; ALPHA-2 AB The details of structure modification on alpha(2/gamma) interface induced by deformation in a hot-deformed Ti-45Al-10Nb alloy were investigated by conventional and high-resolution transmission electron microscopy. A new type of dislocation ledge containing 1/3[111] partials was identified. The Burgers vectors of these dislocation ledges were determined to be 1/2[110] or 1/2[101]. The formation mechanism of this new type of dislocation ledge is discussed. Also, two types of hot deformation induced alpha(2/gamma) interfaces, coherent interfaces with high density of ledges and misoriented semi-coherent alpha(2/gamma) interfacial boundaries were observed. For the misoriented semi-coherent alpha(2 gamma) interfaces, the density of dislocation ledges in these interfaces increases with the misoriented angle between the (111)(gamma) and (0001)(alpha 2) planes, and 1/3[111] partial dislocations were involved in all the dislocation ledges. The formation mechanism of these deformation-induced alpha(2/gamma) interfaces were discussed related to the role of alpha(2/gamma) interfaces adjusting the deformation as a dislocation sink absorbing the slipping dislocations in the gamma phase. Moreover, misoriented semi-coherent alpha(2/gamma) interface related deformation twinning and structure transformation induced by deformation were analyzed and discussed related to the role of alpha(2/gamma) interfaces as a dislocation source during deformation. (C) 2000 Kluwer Academic Publishers. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Sci & Technol Beijing, State Key Lab Adv Met & Mat, Beijing 100083, Peoples R China. Acad Sinica, Inst Met Res, Atom Imaging Solids Lab, Shenyang 110015, Peoples R China. RP Wang, JG (reprint author), Univ Calif Irvine, Dept Chem & Biochem Engn & Mat Sci, 916 Engn Tower, Irvine, CA 92697 USA. NR 54 TC 1 Z9 1 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD JAN PY 2000 VL 35 IS 2 BP 399 EP 409 DI 10.1023/A:1004711216371 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA 277QA UT WOS:000084943200021 ER PT J AU Napolitano, RE Schaefer, RJ AF Napolitano, RE Schaefer, RJ TI The convergence-fault mechanism for low-angle boundary formation in single-crystal castings SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID NICKEL-BASE SUPERALLOY; DIRECTIONAL SOLIDIFICATION; GROWTH AB A set of nickel-based superalloy single-crystal investment castings was evaluated for crystal perfection. Defect structures near the seed emergence point and other geometric features were examined using X-ray topography. Topographic images were compared with metallographically observed dendritic structures to establish a convergence-fault criterion for the location of low-angle boundaries. To support the phenomenological description of low-angle boundary formation through convergence-faulting, a tip-growth model for simulation of the growth of the dendritic network was developed. This model predicts the local primary growth direction from among three possible [001] directions and identifies regions of convergent growth. A connectivity parameter is defined and used to map the locations where convergence-fault formation is most likely. Predictions are compared with experimental observation. (C) 2000 Kluwer Academic Publishers. C1 Natl Inst Stand & Technol, Div Met, Gaithersburg, MD 20899 USA. RP Napolitano, RE (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 12 TC 44 Z9 46 U1 6 U2 36 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PY 2000 VL 35 IS 7 BP 1641 EP 1659 DI 10.1023/A:1004747612160 PG 19 WC Materials Science, Multidisciplinary SC Materials Science GA 281XP UT WOS:000085187000010 ER PT J AU Seal, S Warwick, T Sobczak, N Morgiel, J AF Seal, S Warwick, T Sobczak, N Morgiel, J TI A scanning photoemission microscope (SPEM) to study the interface chemistry of AlTi/C system SO JOURNAL OF MATERIALS SCIENCE LETTERS LA English DT Article ID X-RAY MICROSCOPES; SPECTROMICROSCOPY; CARBON; METALS C1 Univ Cent Florida, Adv Mat Proc & Anal Ctr, Orlando, FL 32828 USA. Univ Calif Berkeley, LBNL, Adv Light Source, Berkeley, CA 94720 USA. Foundry Res Inst, Krakow, Poland. Polish Acad Sci, PL-00901 Warsaw, Poland. RP Seal, S (reprint author), Univ Cent Florida, Adv Mat Proc & Anal Ctr, Orlando, FL 32828 USA. NR 25 TC 6 Z9 6 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0261-8028 J9 J MATER SCI LETT JI J. Mater. Sci. Lett. PD JAN PY 2000 VL 19 IS 2 BP 123 EP 126 DI 10.1023/A:1006647430214 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 276GR UT WOS:000084868500010 ER PT J AU Kutter, JP Jacobson, SC Ramsey, JM AF Kutter, JP Jacobson, SC Ramsey, JM TI Solid phase extraction on microfluidic devices SO JOURNAL OF MICROCOLUMN SEPARATIONS LA English DT Article; Proceedings Paper CT 21st International Symposium on Capillary Chromatography and Electrophoresis CY JUN 20-24, 1999 CL PARK CITY, UTAH DE microfabricated devices; solid phase extraction; neutral dye ID OPEN-CHANNEL ELECTROCHROMATOGRAPHY; POLYMERASE-CHAIN-REACTION; CHEMICAL-ANALYSIS SYSTEMS; CAPILLARY ELECTROPHORESIS; MICROCHIP ELECTROPHORESIS; SAMPLE STACKING; HUMAN DNA; CHIP; PCR; SILICON AB A microfabricated device with C18-coated channels was used to demonstrate on-chip solid phase extraction. Sample solutions containing a neutral dye were enriched and eluted in less than 4 min. Distinct elution peaks with good signal-to-noise ratios were obtained even for highly dilute samples. The gain in concentration estimated from the enrichment and elution volumes was 80-fold. (C) 2000 John Wiley & Sons, Inc. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ramsey, JM (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Kutter, Jorg/E-3256-2010 OI Kutter, Jorg/0000-0003-1065-1985 NR 27 TC 79 Z9 80 U1 2 U2 27 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1040-7685 J9 J MICROCOLUMN SEP JI J. Microcolumn Sep. PY 2000 VL 12 IS 2 BP 93 EP 97 DI 10.1002/(SICI)1520-667X(2000)12:2<93::AID-MCS5>3.0.CO;2-P PG 5 WC Chemistry, Analytical SC Chemistry GA 278TB UT WOS:000085004100005 ER PT J AU Shen, YF Smith, RD AF Shen, YF Smith, RD TI High-resolution capillary isoelectric focusing of proteins using highly hydrophilic-substituted cellulose-coated capillaries SO JOURNAL OF MICROCOLUMN SEPARATIONS LA English DT Article DE capillary isoelectric focusing; polymer coatings; substituted celluloses; polyvinyl alcohol; linear polyacrylamide ID FUSED-SILICA CAPILLARIES; ELECTROPHORESIS AB Highly hydrophilic group-substituted celluloses were immobilized on the fused silica capillary inner wall for capillary isoelectric focusing (CIEF) of proteins. The resultant capillaries were evaluated under typical CIEF conditions, and the results were compared with those obtained by using polyvinyl alcohol (PVA)- and linear polyacrylamide (LPA)-coated capillaries. A minimal resolved pI difference of 0.013 was obtained with a carrier ampholyte (pH 3-10) for hydroxyethyl cellulose- and hydroxypropyl cellulose-coated capillaries, while 0.019 was obtained on PVA- and LPA-coated capillaries. Changing substituted groups from hydroxyl to hydroxylmethyl decreased the CIEF resolution from ca. 2.5 to ca. 1.0 for tested proteins at mobilization speed of ca. 0.9 cm min(-1). Little loss in CIEF resolution was observed when increasing capillary length from 30 to 150 cm, however, flat peaks were observed when increasing column diameter up to > 100 mu m. The present work indicates that mobilization speeds of < 1 cm min(-1) should be used to achieve high CIEF resolution. (C) 2000 John Wiley & Sons, Inc. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 18 TC 99 Z9 100 U1 3 U2 30 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1040-7685 J9 J MICROCOLUMN SEP JI J. Microcolumn Sep. PY 2000 VL 12 IS 3 BP 135 EP 141 DI 10.1002/(SICI)1520-667X(2000)12:3<135::AID-MCS2>3.0.CO;2-5 PG 7 WC Chemistry, Analytical SC Chemistry GA 288TV UT WOS:000085581300002 ER PT J AU Gao, HY Shen, YF Veenstra, TD Harkewicz, R Anderson, GA Bruce, JE Pasa-Tolic, L Smith, RD AF Gao, HY Shen, YF Veenstra, TD Harkewicz, R Anderson, GA Bruce, JE Pasa-Tolic, L Smith, RD TI Two-dimensional electrophoretic/chromatographic separations combined with electrospray ionization FTICR mass spectrometry for high throughput proteome analysis SO JOURNAL OF MICROCOLUMN SEPARATIONS LA English DT Article DE proteomics; two-dimensional separations; CIEF; HPLC-FTICR ID SEQUENCE DATABASES; PROTEINS; IDENTIFICATION; ELECTROPHORESIS; MIXTURES; BIOLOGY; GENOME AB A two-dimensional separation strategy combined with electrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR) is being developed for high throughput proteomic analyses. Capillary isoelectric focusing (CIEF) coupled online with a robotic fraction collector is used to separate and collect microliter fractions of soluble Saccharomyces cerevisiae (yeast) proteins eluting from the capillary into a microtiter plate. Following tryptic digestion of each fraction, the resultant peptides are separated using capillary high performance liquid chromatography (HPLC) and analyzed by online ESI-FTICR. Protein identification is based upon the use of the experimentally measured peptide masses as accurate mass tags, augmented by conventional MS/MS methods as necessary, to identify proteins predicted from the yeast genome sequence. This new separation strategy is being evaluated using proteins extracted from yeast grown in natural isotopic abundance and N-15-enriched media. Two isotopically distinct versions of each peptide are thus observed in the ESI-FTICR spectra. The mass differences between the two versions are used to determine the number of nitrogen atoms in the peptide, and provide an additional constraint that aids protein identification. More importantly, the use of this stable-isotope labeling strategy enables the generation of "comparative displays" of the precise relative protein abundances. This two-dimensional separation strategy combined with ESI-FTICR analysis is expected to be highly amenable to automation. (C) 2000 John Wiley & Sons, Inc. C1 Pacific NW Natl Lab, Environm Mol Sci lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Natl Lab, Environm Mol Sci lab, POB 999,MSIN K8-98, Richland, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 27 TC 25 Z9 25 U1 0 U2 4 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1040-7685 J9 J MICROCOLUMN SEP JI J. Microcolumn Sep. PY 2000 VL 12 IS 7 BP 383 EP 390 DI 10.1002/1520-667X(2000)12:7<383::AID-MCS1>3.0.CO;2-S PG 8 WC Chemistry, Analytical SC Chemistry GA 347LH UT WOS:000088930700001 ER PT J AU Liu, YJ Foote, RS Culbertson, CT Jacobson, SC Ramsey, RS Ramsey, JM AF Liu, YJ Foote, RS Culbertson, CT Jacobson, SC Ramsey, RS Ramsey, JM TI Electrophoretic separation of proteins on microchips SO JOURNAL OF MICROCOLUMN SEPARATIONS LA English DT Article DE proteins; microchips; capillary; electrophoresis ID CAPILLARY ZONE ELECTROPHORESIS; SOLUTE ADSORPTION; PERFORMANCE; PEPTIDES; BUFFERS; SYSTEMS AB A mixture of model proteins was rapidly separated by capillary electrophoresis on a microfabricated device. The proteins were labeled with tetramethylrhodamine isothiocyanate and detected on-chip with laser-induced fluorescence. The small channel dimensions of the device allow the use of high ionic strength buffer to minimize protein adsorption to the channel walls. Electric field strengths as high as 600 V/cm could be applied without significant band distortion in 100 mM sodium phosphate buffer. and separations were completed within 60 seconds. The buffer pH was adjusted to optimize separation of proteins based on charge differences. A zwitterionic buffer additive, betaine, also reduced protein-wall interactions and improved the reproducibility of analyses. (C) 2000 John Wiley & Sons, Inc. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Foote, RS (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 29 TC 27 Z9 28 U1 2 U2 4 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1040-7685 J9 J MICROCOLUMN SEP JI J. Microcolumn Sep. PY 2000 VL 12 IS 7 BP 407 EP 411 DI 10.1002/1520-667X(2000)12:7<407::AID-MCS4>3.0.CO;2-C PG 5 WC Chemistry, Analytical SC Chemistry GA 347LH UT WOS:000088930700004 ER PT J AU Brunkhorst, C Ciotti, D Fredd, E Wilson, JR Geveke, DJ Kozempel, M AF Brunkhorst, C Ciotti, D Fredd, E Wilson, JR Geveke, DJ Kozempel, M TI Development of process equipment to separate nonthermal and thermal effects of RF energy on microorganisms SO JOURNAL OF MICROWAVE POWER AND ELECTROMAGNETIC ENERGY LA English DT Article DE radio frequency; nonthermal; pasteurization ID FOOD AB We developed a modified radio frequency (RF) dielectric heater, as a component of a continuous process, for isolating thermal and nonthermal effects of RF energy on microorganisms in liquid foods. The concept combines instantaneous input of RF energy to the food system with rapid removal of thermal energy. We used a double tube heat exchanger as an integral part of the RF heater. The outer tube was Teflon. The inner tube was stainless steel which was grounded in the RF circuit. Product flowed through the annular region between the two concentric tubes. Cooling water flowed through the grounded stainless steel rubs. The RF energy was absorbed by the process fluid in the annular region. The cooling water flowing in the inner tube removed the thermal energy from the process fluid controlling the temperature. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Brunkhorst, C (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 13 TC 4 Z9 4 U1 2 U2 3 PU INT MICROWAVE POWER INST PI MANASSAS PA 10210 LEATHERLEAF COURT, MANASSAS, VA 22111 USA SN 0832-7823 J9 J MICROWAVE POWER EE JI J. Microw. Power Electromagn. Energy PY 2000 VL 35 IS 1 BP 44 EP 50 PG 7 WC Engineering, Chemical; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 315LM UT WOS:000087115300006 PM 10834188 ER PT J AU Cai, L Struk, B Adams, MD Ji, W Haaf, T Kang, HL Dho, SH Xu, XQ Ringpfeil, F Nancarrow, J Zach, S Schaen, L Stumm, M Niu, TH Chung, J Lunze, K Verrecchia, B Goldsmith, LA Viljoen, D Figuera, LE Fuchs, W Lebwohl, M Uitto, J Richards, R Hohl, D Ramesar, R Callen, DF Kim, UJ Doggett, NA Neldner, KH Lindpainter, K AF Cai, L Struk, B Adams, MD Ji, W Haaf, T Kang, HL Dho, SH Xu, XQ Ringpfeil, F Nancarrow, J Zach, S Schaen, L Stumm, M Niu, TH Chung, J Lunze, K Verrecchia, B Goldsmith, LA Viljoen, D Figuera, LE Fuchs, W Lebwohl, M Uitto, J Richards, R Hohl, D Ramesar, R Callen, DF Kim, UJ Doggett, NA Neldner, KH Lindpainter, K TI A 500-kb region on chromosome 16p13.1 contains the pseudoxanthoma elasticum locus: high-resolution mapping and genomic structure SO JOURNAL OF MOLECULAR MEDICINE-JMM LA English DT Article DE pseudoxanthoma elasticum; genetic mapping; physical mapping; BAC contigs; YAC contigs ID RESISTANCE-ASSOCIATED PROTEIN; LEUKEMIA-CELL LINE; MULTIDRUG-RESISTANCE; EXPORT PUMP; LEUKOTRIENE C-4; PHYSICAL MAP; TUMOR-CELLS; GENE; MRP; GLUTATHIONE AB We have recently mapped the genetic defect underlying pseudoxanthoma elasticum (PXE), an inherited disorder characterized by progressive calcification of elastic fibers in skin, eye, and cardiovascular system, to chromosome 16p13.1. Here we report further data on the fine-mapping and genomic structure of this locus. Haplotype analysis of informative PXE families narrowed the locus to an interval of less than 500 kb located between markers D16B9621 and D16S764. Three overlapping YAC clones were found to cover this region through YAC-STS content mapping. An overlapping BAC contig was then constructed to cover this interval and the surrounding region. About 80% of this chromosomal region has been fully sequenced using the BAC shotgun technique. Gene content and sequence analysis predicted four genes (MRP1, MRP6, PM5, and a novel transcript) and two pseudogenes (ARA and PKD1) within this interval. By screening a somatic cell hybrid panel we were able to precision-map the breakpoint of Cy185 and the starting point of a chromosomal duplication within 20 kb of BAC A962B4. The present data further refine the localization of PXE, provide additional physical cloning resources, and will aid in the eventual identification of the genetic defect causing PXE. C1 Brigham & Womens Hosp, Childrens Hosp, Dept Cardiol,Cardiovasc Div, Boston, MA 02115 USA. Harvard Univ, Sch Med, Dept Cardiol, Boston, MA 02115 USA. Harvard Univ, Sch Med, Dept Med, Boston, MA 02115 USA. Texas Tech Univ, Hlth Sci Ctr, Dept Dermatol, Lubbock, TX 79430 USA. Inst Genom Res, Rockville, MD 20850 USA. CALTECH, Div Biol, Caltech Genome Res Lab, Pasadena, CA 91125 USA. Univ Calif Los Alamos Natl Lab, Div Life Sci, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Human Genome Studies, Los Alamos, NM 87545 USA. Womens & Childrens Hosp, Dept Cytogenet & Mol Genet, Adelaide, SA 5006, Australia. Thomas Jefferson Univ, Jefferson Med Coll, Dept Dermatol & Cutaneous Biol, Philadelphia, PA 19107 USA. CUNY Mt Sinai Sch Med, Dept Dermatol, New York, NY 10029 USA. Univ Cape Town, Sch Med, Dept Human Genet, ZA-7925 Cape Town, South Africa. CUNY Mt Sinai Sch Med, Dept Ophthalmol, New York, NY 10029 USA. Univ Lausanne, Dept Dermatol, CH-1011 Lausanne, Switzerland. Univ Rochester, Dept Dermatol, Rochester, NY 14642 USA. Univ Guadalajara, Sch Med, CIBO IMSS, Div Genet, Guadalajara 44430, Jalisco, Mexico. Univ Guadalajara, Sch Med, CIBO IMSS, Dept Mol Med, Guadalajara 44430, Jalisco, Mexico. S African Inst Med Res, Johannesburg, South Africa. Max Planck Inst Mol Genet, Berlin, Germany. Otto Von Guericke Univ, Inst Human Genet, Magdeburg, Germany. Celera Genom, Rockville, MD 20850 USA. Max Delbruck Ctr Mol Med, D-13122 Berlin, Germany. F Hoffmann La Roche Ltd, Roche Genet, Div Pharmaceut, CH-4070 Basel, Switzerland. RP Lindpainter, K (reprint author), Brigham & Womens Hosp, Childrens Hosp, Dept Cardiol,Cardiovasc Div, 75 Francis St, Boston, MA 02115 USA. RI Callen, David/G-1975-2012; Ramesar, Raj/I-6941-2015; OI Ramesar, Raj/0000-0001-5688-1634; Callen, David/0000-0002-6189-9991 FU NHLBI NIH HHS [HL09783, K04-HL03138-01] NR 37 TC 48 Z9 49 U1 0 U2 5 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0946-2716 J9 J MOL MED-JMM JI J. Mol. Med. PY 2000 VL 78 IS 1 BP 36 EP 46 DI 10.1007/s001090000079 PG 11 WC Genetics & Heredity; Medicine, Research & Experimental SC Genetics & Heredity; Research & Experimental Medicine GA 289TJ UT WOS:000085637800005 PM 10759028 ER PT J AU Wozny, CE Noid, DW Sumpter, BG AF Wozny, CE Noid, DW Sumpter, BG TI A dynamical method for calculating the near infrared spectra of molecules and macromolecules SO JOURNAL OF NEAR INFRARED SPECTROSCOPY LA English DT Article DE semi-classical spectral method; molecular dynamics; polymers; near infrared spectra; anharmonic effects; frequency estimator ID VIBRATIONAL-SPECTRA; DISPERSION-CURVES; LINEAR-POLYMERS; TRAJECTORIES; INTENSITIES AB The Semi-classical Spectral Method (SSM) may be used to calculate the overtone vibrational frequencies of near infrared (NIR spectra for molecules and polymers, According to the theory, the transition frequency between two quantum states, n and m, may be found from the relation omega(nm) = (m-n)omega((n) over bar), where (n) over bar = (n+m)/2, The variable (n) over bar is a semi-classical eigenvalue associated with the action of a vibrational mode, and omega((n) over bar) is the vibrational frequency of a dynamical trajectory which has an action J = ((n) over bar + 1/2)(h) over bar in the mode of interest. Frequencies are calculated from a classical trajectory using the MUSIC frequency estimator, A normal mode analysis is not able to calculate overtone frequencies because that approach does not allow for a variable such as (n) over bar. The accuracy and significance of the method is demonstrated by two examples. First, the method is applied to the Morse potential, which is an analytical function with exact solutions. Second, it is applied to a model of polyethylene in order to calculate the overtone spectra of the CH2 anti-symmetric and symmetric stretching vibrations. C1 Waycross Coll, Waycross, GA 31503 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Wozny, CE (reprint author), Waycross Coll, 2001 Georgia Pkwy, Waycross, GA 31503 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 30 TC 0 Z9 0 U1 0 U2 1 PU N I R PUBLICATIONS PI CHICHESTER PA 6 CHARLTON MILL, CHARLTON, CHICHESTER PO18 0HY, WEST SUSSEX, ENGLAND SN 0967-0335 J9 J NEAR INFRARED SPEC JI J. Near Infrared Spectrosc. PY 2000 VL 8 IS 2 BP 133 EP 150 PG 18 WC Chemistry, Applied; Spectroscopy SC Chemistry; Spectroscopy GA 305BK UT WOS:000086518800008 ER PT J AU Smilowitz, HM Joel, DD Slatkin, DN Micca, PL Nawrocky, MM Youngs, K Tu, W Coderre, JA AF Smilowitz, HM Joel, DD Slatkin, DN Micca, PL Nawrocky, MM Youngs, K Tu, W Coderre, JA TI Long-term immunological memory in the resistance of rats to transplanted intracerebral 9L gliosarcoma (9LGS) following subcutaneous immunization with 9LGS cells SO JOURNAL OF NEURO-ONCOLOGY LA English DT Article DE aging; BNCT; glioma; immunological memory; vaccine ID NEUTRON-CAPTURE THERAPY; ANTITUMOR IMMUNE-RESPONSE; BRAIN-TUMORS; GLIOBLASTOMA-MULTIFORME; IMMUNOGENIC TUMOR; IMMUNOTHERAPY; GLIOMAS; GROWTH; MICE; IMMUNOBIOLOGY AB Glioblastoma multiforme (GBM) is the most common primary human brain tumor. About 7000 new cases are diagnosed yearly in the USA. Despite current neurosurgical and postoperative radiotherapeutic tumor cytoreduction methods, in most cases occult foci of tumor cells infiltrate surrounding edematous brain tissues and cause recurrent disease within one year. GEM is almost invariably fatal within a few years after it is diagnosed. Our goal is to achieve long-term control of GEM by combining immunoprophylaxis with a radiation-based technique, such as boron neutron-capture therapy (BNCT), potentially capable of specifically targeting the infiltrating tumor cells while sparing the surrounding normal brain tissue. It has long been known that the subcutaneous (sc) injection of irradiated cells or untreated cultured cells (and the removal of the resulting tumors) derived from the well characterized, highly immunogenic 9L gliosarcoma (9LGS) rat model into young isogenic rats can prevent tumor growth after subsequent sc or intracranial (ic) injection of untreated, otherwise lethal 9LGS cells. In this study we have confirmed, quantified and extended those findings to study the efficacy of such immunological memory in normal aging rats and in aging rats previously treated for ic 9LGS tumors by BNCT. (1) The sc injection of 5,000,000 untreated 9LGS cells and the surgical removal of the resulting tumors (method A) protected 80% of normal young rats from an ic challenge with 10,000 untreated 9LGS cells, and a single sc injection of 5,000,000 lethally X-irradiated 9LGS cells (method B) protected 66% of them, but multiple sc injections with a crude particulate fraction prepared from 9LGS cells were not protective. Protection is long-lasting since contralateral ic rechallenge of six-month survivors with an injection of 10,000 viable 9LGS cells resulted in 100% survival. (2) Normal one-year-old rats were only slightly less protected than were normal young rats, similar to 70% rather than similar to 80% (method A) and similar to 60% rather than - 66% (method B). (3) BNCT treatment alone resulted in partial immunological protection, as 30% of one-year post-BNCT survivors of ic 9LGS tumors prevailed after contralateral ic rechallenge with 10,000 viable 9LGS cells. Moreover a single sc immunization with 5,000,000 untreated 9LGS cells prior to ic rechallenge boosted survival from 30% to 100%. The relevance of these observations to strategies of preclinical experimentation for immunoprophylaxis of malignant gliomas is discussed. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Univ Connecticut, Ctr Hlth, Dept Pharmacol, Farmington, CT USA. RP Coderre, JA (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. NR 51 TC 8 Z9 8 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0167-594X J9 J NEURO-ONCOL JI J. Neuro-Oncol. PY 2000 VL 46 IS 3 BP 193 EP 203 DI 10.1023/A:1006488301412 PG 11 WC Oncology; Clinical Neurology SC Oncology; Neurosciences & Neurology GA 331UB UT WOS:000088036100001 PM 10902851 ER PT J AU Smilowitz, HM Micca, PL Nawrocky, MM Slatkin, DN Tu, W Coderre, JA AF Smilowitz, HM Micca, PL Nawrocky, MM Slatkin, DN Tu, W Coderre, JA TI The combination of boron neutron-capture therapy and immunoprophylaxis for advanced intracerebral gliosarcomas in rats SO JOURNAL OF NEURO-ONCOLOGY LA English DT Article DE BNCT; glioma; immunoprophylaxis; immunological memory; radiotherapy ID COLONY-STIMULATING FACTOR; EXPERIMENTAL BRAIN-TUMORS; ACTIVATED KILLER-CELLS; MEDIATED GENE-THERAPY; IN-VIVO; ANTITUMOR IMMUNITY; GLIOMA-CELLS; PARA-BORONOPHENYLALANINE; INTERLEUKIN-2; IMMUNOTHERAPY AB Glioblastoma multiforme (GBM) is the most common primary human brain tumor. About 7000 new cases are diagnosed yearly in the USA and GEM is almost invariably fatal within a few years after it is diagnosed. Despite current neurosurgical and radiotherapeutic tumor cytoreduction methods, in most cases occult foci of tumor cells infiltrate surrounding brain tissues and cause recurrent disease. Therefore the combination of neurosurgical and radiotherapeutic debulking methods with therapies to inhibit occult GEM cells should improve prognosis. In this study we have combined boron neutron-capture therapy (BNCT), a novel binary radiotherapeutic treatment modality that selectively irradiates tumor tissue and largely spares normal brain tissue, with immunoprophylaxis, a form of active immunization initiated soon after BNCT treatment, to treat advanced, clinically relevantly-sized brain tumors in rats. Using a malignant rat glioma model of high immunogenicity, the 9L gliosarcoma, we have shown that about half of the rats that would have died after receiving BNCT debulking alone, survived after receiving BNCT plus immunoprophylaxis. Further, most of the surviving rats display immunological-based resistance to recurrent 9LGS growth six months or more after treatment. To our knowledge this study represents the first time BNCT and immunoprophylaxis have been combined to treat advanced brain tumors in rats. C1 Univ Connecticut, Ctr Hlth, Sch Med, Dept Pharmacol, Farmington, CT 06030 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Smilowitz, HM (reprint author), Univ Connecticut, Ctr Hlth, Sch Med, Dept Pharmacol, 263 Farmington Ave, Farmington, CT 06030 USA. NR 60 TC 7 Z9 7 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0167-594X J9 J NEURO-ONCOL JI J. Neuro-Oncol. PY 2000 VL 46 IS 3 BP 231 EP 240 DI 10.1023/A:1006409721365 PG 10 WC Oncology; Clinical Neurology SC Oncology; Neurosciences & Neurology GA 331UB UT WOS:000088036100004 PM 10902854 ER PT J AU King, ME Binder, LI Wall, JS Ksiezak-Reding, H AF King, ME Binder, LI Wall, JS Ksiezak-Reding, H TI Globular aggregates precede arachidonic acid-induced filaments and have tau packing density similar to authentic PHFs. SO JOURNAL OF NEUROCHEMISTRY LA English DT Meeting Abstract C1 Northwestern Univ, Dept Cell & Mol Biol, Chicago, IL 60611 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. Yeshiva Univ Albert Einstein Coll Med, Dept Pathol, Bronx, NY 10461 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0022-3042 J9 J NEUROCHEM JI J. Neurochem. PY 2000 VL 74 SU S BP S28 EP S28 PG 1 WC Biochemistry & Molecular Biology; Neurosciences SC Biochemistry & Molecular Biology; Neurosciences & Neurology GA 285DB UT WOS:000085373200113 ER PT J AU Pan, JW Rothman, DL Behar, KL Hetherington, HP AF Pan, JW Rothman, DL Behar, KL Hetherington, HP TI Human brain beta-hydroxybutyrate and lactate increase in fasting induced ketosis SO JOURNAL OF NEUROCHEMISTRY LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11793 USA. Yale Univ, Dept Radiol, New Haven, CT 06520 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0022-3042 J9 J NEUROCHEM JI J. Neurochem. PY 2000 VL 74 SU S BP S16 EP S16 PG 1 WC Biochemistry & Molecular Biology; Neurosciences SC Biochemistry & Molecular Biology; Neurosciences & Neurology GA 285DB UT WOS:000085373200062 ER PT J AU Aziz, T Peress, NS Diaz, A Capala, J Chanana, A AF Aziz, T Peress, NS Diaz, A Capala, J Chanana, A TI Postmortem neuropathological features secondary to boron neutron capture therapy for glioblastoma multiforme SO JOURNAL OF NEUROPATHOLOGY AND EXPERIMENTAL NEUROLOGY LA English DT Article DE boron neutron capture therapy; glioblastoma multiforme; Lewy body; neurofibrillary tangle; radiation; senile plaque ID RAT SPINAL-CORD; CENTRAL NERVOUS-SYSTEM; LATE RADIATION-DAMAGE; WHITE MATTER; X-RAYS; IRRADIATION; BRAIN; SINGLE AB This postmortem study of 12 patients with glioblastoma multiforme (GBM) treated with boron neutron capture therapy (BNCT) employing an epithermal neutron beam and p-boronophenylalanine describes the neuropathological findings in patients receiving a relatively high radiation dose to the tumor, bur a relatively low radiation dose to the normal brain. In addition to a standardized neuropathology panel of sections, we used individual treatment dosimetry maps to select sections along the projected maximum radiation beam pathway. We found that the normal neuroparenchyma exposed to the highest radiation dose exhibited a single instance of radiation-induced focal venular fibrinoid necrosis and a single instance of multifocal demyelination. Semiquantitative analysis of pretreatment neurosurgical and postmortem tumor samples revealed only two radiation ascribed histopathological findings to be particular to therapy, fibrinoid necrosis and vascular hyalinization. In this relatively small series of cases we found an unexpectedly high frequency of cases (3 of 12) with neurodegenerative histopathology (Lewy bodies, neurofibrillary tangles, and neuritic senile plaques), which appeared, by distribution, to be independent of the radiation beam. Two of these patients were over 70 yr of age. One was only 41. Our findings suggest an acceptable radiation-induced level of neurotoxicity at the lower doses employed, but raise the possibility of unexpected boron neurodegenerative toxicity. C1 SUNY Stony Brook, Univ Hosp, Dept Pathol, Div Neuropathol, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Peress, NS (reprint author), SUNY Stony Brook, Univ Hosp, Dept Pathol, Div Neuropathol, Level 2, Stony Brook, NY 11794 USA. NR 45 TC 13 Z9 13 U1 0 U2 0 PU AMER ASSN NEUROPATHOLOGISTS INC PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 USA SN 0022-3069 J9 J NEUROPATH EXP NEUR JI J. Neuropathol. Exp. Neurol. PD JAN PY 2000 VL 59 IS 1 BP 62 EP 73 PG 12 WC Clinical Neurology; Neurosciences; Pathology SC Neurosciences & Neurology; Pathology GA 279FL UT WOS:000085033700007 PM 10744036 ER PT J AU Sandi, G Gerald, RE Scanlon, LG Johnson, CS Klingler, RJ Rathke, JW AF Sandi, G Gerald, RE Scanlon, LG Johnson, CS Klingler, RJ Rathke, JW TI Molecular orbital and Li-7 nmr investigation of the influence of curved lattices in lithium intercalated carbon anodes SO JOURNAL OF NEW MATERIALS FOR ELECTROCHEMICAL SYSTEMS LA English DT Article DE molecular orbital calculations; in situ Li-7NMR; carbon electrodes; corannulene electrodes ID CORANNULENE; ELECTROCHEMISTRY; ELECTRODES AB We have performed molecular orbital (MO) calculations, electrochemical, and NMR studies to elucidate the influence of curved and planar carbon lattices on the nature of lithium bonding in lithium intercalated carbon anodes, in order to correlate molecular structure with that required far high-capacity lithium carbon anodes. Electrodes were mane of corannulene (C20H10) and graphite. The voltage profile of corannulene is very similar to that obtained for disordered carbons and the capacity delivered in the first cycle corresponds to 802 mAh/g (reversible capacity of 464 mAh/g). Based on the NMR and MO studies, it was found that Li-corannulene complexes can have lithium character only, with a high tendency to form clusters. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. USAF, Res Lab, Battery Branch, Wright Patterson AFB, OH 45433 USA. RP Sandi, G (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 20 TC 15 Z9 15 U1 0 U2 4 PU ECOLE POLYTECHNIQUE MONTREAL PI MONTREAL PA C P 6079, SUCC CENTRE-VILLE, MONTREAL, QC H3C 3A7, CANADA SN 1480-2422 J9 J NEW MAT ELECT SYST JI J. New Mat.Electrochem. Syst. PD JAN PY 2000 VL 3 IS 1 BP 13 EP 19 PG 7 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 296ZZ UT WOS:000086057800004 ER PT J AU Almazouzi, A Victoria, M de la Rubia, TD Singh, BN AF Almazouzi, A Victoria, M de la Rubia, TD Singh, BN TI Proceedings of the International Workshop on Basic Aspects of Differences in Irradiation Effects Between fcc, bcc and hcp Metals and Alloys - Preface SO JOURNAL OF NUCLEAR MATERIALS LA English DT Editorial Material C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. EPFL, CRPP Fus Technol Mat, Roskilde, Denmark. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP VII EP VII PG 1 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400001 ER PT J AU Caturla, MJ Soneda, N Alonso, E Wirth, BD de la Rubia, TD Perlado, JM AF Caturla, MJ Soneda, N Alonso, E Wirth, BD de la Rubia, TD Perlado, JM TI Comparative study of radiation damage accumulation in Cu and Fe SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID STOCHASTIC ANNEALING SIMULATION; ENERGY DISPLACEMENT CASCADES; DEFECT PRODUCTION; COMPUTER-SIMULATION; MOLECULAR-DYNAMICS; FCC METALS; INTERSTITIAL CLUSTERS; VACANCY CLUSTERS; COPPER; BCC AB Bcc and fee metals exhibit significant differences in behavior when exposed to neutron or heavy ion irradiation. Transmission electron microscopy (TEM) observations reveal that damage in the form of stacking fault tetrahedra (SFT) is visible in copper irradiated to very low doses, but that no damage is visible in iron irradiated to the same total dose. In order to understand and quantify this difference in behavior, we have simulated damage production and accumulation in fee Cu and bcc Fe. We use 20 keV primary knock-on atoms (PKAs) at a homologous temperature of 0.25 of the melting point. The primary damage state was calculated using molecular dynamics (MD) with empirical, embedded-atom interatomic potentials. Damage accumulation was modeled using a kinetic Monte Carlo (kMC) algorithm to follow the evolution of all defects produced in the cascades. The diffusivities and binding energies of defects are input data for this simulation and were either extracted from experiments, the literature, or calculated using MD. MD simulations reveal that vacancy clusters are produced within the cascade core in the case of copper. In iron, most of the vacancies do not cluster during cooling of the cascade core and are available for diffusion. In addition, self-interstitial atom (SIA) clusters are produced in copper cascades but those observed in iron are smaller in number and size. The combined MD/kMC simulations reveal that the visible cluster densities obtained as a function of dose are at least one order of magnitude lower in Fe than in Cu. We compare the results with experimental measurements of cluster density and find excellent agreement between the simulations and experiments when small interstitial clusters are considered to be mobile as suggested by recent MD simulations. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94551 USA. Cent Res Inst Elect Power Ind, Tokyo 201, Japan. Univ Politecn Madrid, Inst Fus Nucl, Madrid, Spain. RP Caturla, MJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, POB 808, Livermore, CA 94551 USA. RI Caturla, Maria /D-6241-2012; Wirth, Brian/O-4878-2015 OI Caturla, Maria /0000-0002-4809-6553; Wirth, Brian/0000-0002-0395-0285 NR 43 TC 147 Z9 150 U1 3 U2 61 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 13 EP 21 DI 10.1016/S0022-3115(99)00220-2 PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400003 ER PT J AU Stoller, RE AF Stoller, RE TI The role of cascade energy and temperature in primary defect formation in iron SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID PRIMARY DAMAGE FORMATION; DISPLACEMENT CASCADES; MOLECULAR-DYNAMICS; COMPUTER-SIMULATION; ALPHA-IRON; METALS; BCC AB Molecular dynamics (MD) simulations have been used to investigate the formation of atomic displacement cascades in iron with energies up to 50 keV (corresponding to a primary knock-on atom (PKA) energy of 79 keV) at 100 K, up to 20 keV at 600 K, and up to 10 keV at 900 K. The cascade damage production has been characterized in terms of several parameters: the number of surviving point defects, the fraction and type of surviving point defects found in clusters, and the size distributions of the in-cascade point defect clusters. A sufficient number of simulations have been completed at each condition to evaluate the statistical variation in these primary damage parameters as a function of irradiation temperature and cascade energy. The energy dependence of stable defect formation can be conveniently separated into three regimes with the number of defects in each regime correlated by a simple power law with a characteristic exponent. The primary effects of cascade energy on defect formation at high energies are explained in terms of subcascade formation. Only a modest effect of temperature is observed on defect survival, while irradiation temperature increases lead to a slight increase in the in-cascade interstitial clustering fraction and a decrease in the vacancy clustering fraction. Cascade energy has little effect on the in-cascade clustering fractions above about 5 keV. However, there is a systematic change in the cluster size distribution, with higher energy cascades producing larger clusters. The loosely coupled nature of the in-cascade vacancy clusters persists at higher energies. (C) 2000 Elsevier Science B.V. All rights reserved. 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 27 TC 142 Z9 146 U1 1 U2 29 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 22 EP 32 DI 10.1016/S0022-3115(99)00204-4 PG 11 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400004 ER PT J AU Wirth, BD Odette, GR Maroudas, D Lucas, GE AF Wirth, BD Odette, GR Maroudas, D Lucas, GE TI Dislocation loop structure, energy and mobility of self-interstitial atom clusters in bcc iron SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID PRESSURE-VESSEL STEELS; MOLECULAR-DYNAMICS; MICROSTRUCTURAL EVOLUTION; DISPLACEMENT CASCADES; ALPHA-IRON; METALS AB Molecular-statics and molecular-dynamics (MD) simulations based on the embedded-atom method (EAM) were used to model the energy and mobility of self-interstitial atom (SIA) clusters in bcc alpha-iron, Isolated SIAs and SIA clusters, directly produced in displacement cascades have significant impact on the microstructural evolution under neutron and high-energy charged particle beam irradiations. The SIA clusters are composed of [111] split dumbbells and crowdions bound by energies in excess of 1 eV. The clusters can be described as perfect prismatic dislocation loops with Burgers vector b = (a/2)[111]. As the loops grow, SIAs fill successive jogged edge rows, with minimum free energy cusps found at the 'magic' numbers corresponding to un-jogged filled hexagonal shells. The total energy of the clusters is in excellent agreement with continuum elasticity dislocation theory predictions. However, the core region is extended compared to an isolated edge dislocation. The extended regions are preferentially located at the hexagonal corners of the loop, forming intrinsic kinks. As a result of the intrinsic kinks, the SIA clusters are highly mobile and undergo one-dimensional motion on their glide prism. The high cluster mobility is related to the easy motion of the edge segments which propagate the kinks along the loop periphery resulting in increments of prismatic glide. The corresponding activation energy for SIA cluster diffusion is less than 0.1 eV. Linking atomistic point defect cluster calculations dislocation theory provides a powerful tool in understanding radiation damage. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Santa Barbara, Dept Mech Engn, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Chem Engn, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Mat Engn, Santa Barbara, CA 93106 USA. RP Wirth, BD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Div, POB 808,L353, Livermore, CA 94551 USA. RI Wirth, Brian/O-4878-2015 OI Wirth, Brian/0000-0002-0395-0285 NR 30 TC 108 Z9 108 U1 1 U2 37 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 33 EP 40 DI 10.1016/S0022-3115(99)00166-X PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400005 ER PT J AU Kirk, MA Jenkins, ML Fukushima, H AF Kirk, MA Jenkins, ML Fukushima, H TI The search for interstitial dislocation loops produced in displacement cascades at 20 K in copper SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID TRANSMISSION ELECTRON-MICROSCOPY; MOLECULAR-DYNAMICS; DAMAGE; IRRADIATION; CLUSTERS AB A low-temperature in situ ion-irradiation and annealing experiment has been performed in copper. Most 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 the 55 defects measured under a range of weakly diffracting conditions, seven showed measurable size decreases while three 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 at different locations. The remaining defects persisted through the anneal, sometimes however with modified morphologies. Video microscopy suggested that the disappearance and appearance of clusters occurred gradually and was unlikely to be due to loop movement. Some arguments on the possible nature of these clusters are presented. On warming specimens to room temperature, a high density of small stacking-fault tetrahedra appeared close to the electron-exit surface of the foil in regions which had been exposed to the electron beam at low temperatures. These are most likely due to the clustering of vacancies produced by sputtering at the back surface. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Oxford, Dept Mat, Oxford OX1 3PH, England. Hiroshima Univ, Fac Engn, Hiroshima 7398527, Japan. RP Kirk, MA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 11 Z9 11 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 50 EP 58 DI 10.1016/S0022-3115(99)00168-3 PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400007 ER PT J AU Heinisch, HL Singh, BN Golubov, SI AF Heinisch, HL Singh, BN Golubov, SI TI Kinetic Monte Carlo studies of the effects of Burgers vector changes on the reaction kinetics of one-dimensionally gliding interstitial clusters SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID DEFECT AB Kinetic Monte Carlo simulations of one-dimensionally diffusing interstitial clusters (dislocation loops) are used to gain insight into their role in microstructure evolution under irradiation. The simulations investigate the changes in reaction kinetics of these defects as a function of changes in the Burgers vector and variation in the size and density of randomly or periodically distributed sinks. In this paper we report on several kinetic Monte Carlo studies intended to elucidate the effects of mixed 1-D/3-D migration relative to pure 3-D and pure 1-D migration. We have investigated the effects of variation of the average distance traveled between Burgers vector changes [L] on the absorption of individual defects into absorbers of varying size and varying concentration, as well as the effects of variation in [L] on the time dependence of absorption of a collection of defects into an array of absorbers. Significant effects of Burgers vector changes on the reaction kinetics of the diffusing interstitial clusters are clearly demonstrated. Even when [L] is large relative to the size and spacing of microstructural features, significant effects of mixed 1-D/3-D migration on reaction kinetics are evident. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Riso Natl Lab, Mat Res Dept, DK-4000 Roskilde, Denmark. Inst Phys & Power Engn, Obninsk 249020, Russia. RP Heinisch, HL (reprint author), Pacific NW Lab, POB 999,MS P8-15, Richland, WA 99352 USA. NR 7 TC 21 Z9 21 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 59 EP 64 DI 10.1016/S0022-3115(99)00169-5 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400008 ER PT J AU Garner, FA Toloczko, MB Sencer, BH AF Garner, FA Toloczko, MB Sencer, BH TI Comparison of swelling and irradiation creep behavior of fcc-austenitic and bcc-ferritic/martensitic alloys at high neutron exposure SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID CASCADE DAMAGE CONDITIONS; SIMPLE FERRITIC ALLOYS; FE-CR ALLOYS; MICROSTRUCTURAL EXAMINATION; EVOLUTION; REACTOR; STEELS; DPA; FLUENCE; RATES AB It is well-known that ferritic and ferritic/martensitic steels develop much less swelling than austenitic steels during neutron or charged particle irradiation. The prevailing assumption is usually that the steady-state swelling rate of bce steels is inherently much lower than that of fee steels, at least a factor of ten or more. It is shown in this paper that this perception is incorrect, with bcc steels having steady-state swelling rates perhaps only a factor two to four lower. It is thought to be significant that the creep compliance of the two types of alloys also differs only by a factor of about two. The lower swelling observed in bce steels relative to fee steels is shown in this paper to be primarily a consequence of much longer transient regimes prior to the onset of steady-state swelling. Several other commonly held perceptions concerning the swelling of both bcc and fee steels are examined in this paper and also shown to require revision. These involve the effect of cold-work on swelling, the extent of the temperature regime of swelling, and the possibility that swelling might saturate eventually. It also appears that the use of well-controlled in-reactor materials tests that employ active temperature control tend to yield significantly lower values of void swelling compared to that obtained under more representative conditions typical of actual reactor operation. The role of previously ignored differences in displacement rate to determine the duration of the transient regime of void swelling is also shown to require reevaluation, especially for bce steels. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Washington State Univ, Pullman, WA 99164 USA. New Mexico Inst Min & Technol, Socorro, NM USA. RP Garner, FA (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 76 TC 197 Z9 201 U1 12 U2 60 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 123 EP 142 DI 10.1016/S0022-3115(99)00225-1 PG 20 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400014 ER PT J AU Zbib, HM de la Rubia, TD Rhee, M Hirth, JP AF Zbib, HM de la Rubia, TD Rhee, M Hirth, JP TI 3D dislocation dynamics: stress-strain behavior and hardening mechanisms in fcc and bcc metals SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID PLASTIC-DEFORMATION; SINGLE-CRYSTALS; SIMULATION; COPPER; SLIP AB A dislocation dynamics (DD) model for plastic deformation, connecting the macroscopic mechanical properties to basic physical laws governing dislocation mobility and related interaction mechanisms, has been developed. In this model there is a set of critical reactions that determine the overall results of the simulations, such as the stress-strain curve. These reactions are annihilation, formation of jogs, junctions, and dipoles and cross-slip. In this paper, we discuss these reactions and the manner in which they influence the simulated stress-strain behavior of fee and bcc metals. In particular, we examine the formation (zipping) and strength of dipoles and junctions, and effect of jogs, using the dislocation dynamics model. We show that the strengths (unzipping) of these reactions for various configurations can be determined by direct evaluation of the elastic interactions. Next, we investigate the phenomenon of hardening in metals subjected to cascade damage. The investigated microstructure consists of small dislocation loops decorating the mobile dislocations. Preliminary results reveal that these loops act as hardening agents, trapping the dislocations and resulting in increased yield stress. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Washington State Univ, Sch Mech & Mat Engn, Pullman, WA 99164 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Zbib, HM (reprint author), Washington State Univ, Sch Mech & Mat Engn, Pullman, WA 99164 USA. NR 29 TC 91 Z9 91 U1 1 U2 23 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 154 EP 165 DI 10.1016/S0022-3115(99)00175-0 PG 12 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400016 ER PT J AU Ghoniem, NM Singh, BN Sun, LZ de la Rubia, TD AF Ghoniem, NM Singh, BN Sun, LZ de la Rubia, TD TI Interaction and accumulation of glissile defect clusters near dislocations SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID DISPLACEMENT CASCADES; MOLECULAR-DYNAMICS; METALS; LOOPS; BCC AB Accumulation of nano-size prismatic defect clusters near slip-dislocations results from their mutual elastic interaction. We present here 3-D isotropic elasticity calculations for the interaction energy between radiation-induced nano-size prismatic loops and grown-in dislocation loops. The current treatment extends the work of Trinkaus et al. in two respects. First, a computational method for full 3-D analysis of interaction energies in bce Fe and fee Cu is developed. Second, the theoretical method of Kroupa is computationally implemented for rigorous calculations of force, torque and induced surface energy on defect clusters. It is shown that small clusters are trapped within a zone of similar to 10 nm in bcc Fe, and similar to 20 nm in fee Cu at room temperature, in rough agreement with experimental observations. Clusters can be absorbed in the core of grown-in dislocations because of unbalanced moments, which provide sufficient energy for rotation of their Burgers vectors in a zone of 2-3 nm in Fe. Near the dislocation core (within a few nanometers), sessile defect clusters in Cu are shown to convert to a glissile configuration. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Angeles, Dept Mech & Aerosp Engn, Los Angeles, CA 90095 USA. Riso Natl Lab, DK-4000 Roskilde, Denmark. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Ghoniem, NM (reprint author), Univ Calif Los Angeles, Dept Mech & Aerosp Engn, Los Angeles, CA 90095 USA. RI Ghoniem, Nasr/A-9799-2008; Sun, Lizhi/C-5205-2008 NR 20 TC 44 Z9 44 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 166 EP 177 DI 10.1016/S0022-3115(99)00176-2 PG 12 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400017 ER PT J AU Caturla, MJ Wall, M Alonso, E de la Rubia, TD Felter, T Fluss, MJ AF Caturla, MJ Wall, M Alonso, E de la Rubia, TD Felter, T Fluss, MJ TI Heavy ion irradiation and annealing of lead: atomistic simulations and experimental validation SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID DEFECT PRODUCTION; CASCADES; METALS; EVOLUTION; COMPUTER; FE AB We simulated the evolution of the defect microstructure resulting from irradiation of lead with 180 keV Er+ at liquid Nitrogen temperature followed by an isochronal anneal up to 350 K. The results were validated by comparison with experiments. The simulation consists of a coupled molecular dynamics (MD) and kinetic Monte Carlo (KMC) calculation that follows the production and migration of defects during irradiation and subsequent isochronal annealing. Defect diffusivities and cluster energetics were calculated by MD simulations with and embedded atom-like potential for Pb, or obtained from experiments whenever available. The primary stage of the damage produced by the energetic recoils was also calculated using MD. These calculations show the formation of dense interstitial and vacancy clusters after the cooling of the cascade. The ions are implanted at a temperature of 94 K and the damage is annealed by increasing the temperature on a stepwise fashion by 50 K every 5 min. The time-temperature evolution of the density of point defects and defect clusters is calculated in this simulation. The results are compared with experimental observations for the same irradiation and annealing conditions. The experiments consist of a set of transmission electron microscope (TEM) micrographs taken at different times during the anneal. The micrographs show the presence of loops after irradiation at 94 K, the increase in loop density with temperature, and the disappearance of all the loops at temperatures of similar to 340 K. These results are in good agreement with the simulations, which help us understand the underlying processes occurring during irradiation and annealing. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. RP Caturla, MJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, POB 808, Livermore, CA 94550 USA. RI Caturla, Maria /D-6241-2012 OI Caturla, Maria /0000-0002-4809-6553 NR 20 TC 8 Z9 8 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 186 EP 193 DI 10.1016/S0022-3115(99)00202-0 PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400019 ER PT J AU Alonso, E Caturla, MJ de la Rubia, TD Perlado, JM AF Alonso, E Caturla, MJ de la Rubia, TD Perlado, JM TI Simulation of damage production and accumulation in vanadium SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID FREELY MIGRATING DEFECTS; DISPLACEMENT CASCADES; MOLECULAR-DYNAMICS; COMPUTER-SIMULATION; ION IRRADIATION; ANNEALING KINETICS; METALS; ALLOYS; DIFFUSION; EVOLUTION AB Energetic atoms which have been knocked-off their lattice sites by neutron or ion irradiation leave a trail of vacancies and interstitials in their wake. Most of these defects recombine with their opposites within their own collision cascade. Some fraction, however, escape to become freely migrating defects (FMD) in the bulk of the material. The interaction of FMD with the microstructure has long been linked to changes in the macroscopic properties of materials under irradiation. We calculate the fraction of FMD in pure vanadium for a wide range of temperatures and primary knock-on atom (PKA) energies. The collision cascade database is obtained from molecular dynamics (MD) simulations with an embedded atom method (EAM) potential. The actual FMD calculation is carried out by a kinetic Monte Carlo (kMC) code with a set of parameters extracted either from the experimental literature or from MD simulations. Annealing each individual cascade at different temperatures allows the mobile species to escape and account for FMD. We also analyze damage accumulation in a specimen irradiated at low dose rate in the presence of impurities. At the temperature studied, beginning of stage V, we observe that only vacancies are free to move whereas most interstitials are stopped by impurities. We also analyze the role of impurities on damage accumulation and on the concentration of mobile defects. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Inst Fus Nucl, Madrid 28006, Spain. RP Alonso, E (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. RI Caturla, Maria /D-6241-2012 OI Caturla, Maria /0000-0002-4809-6553 NR 41 TC 25 Z9 28 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 221 EP 229 DI 10.1016/S0022-3115(99)00181-6 PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400023 ER PT J AU Perlado, JM Malerba, L Sanchez-Rubio, A de la Rubia, TD AF Perlado, JM Malerba, L Sanchez-Rubio, A de la Rubia, TD TI Analysis of displacement cascades and threshold displacement energies in beta-sic SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID INTERATOMIC POTENTIALS; SIMULATION; SILICON AB The threshold displacement energy (TDE) for both Si and C atoms in SIC at 300 K has been determined by means of molecular dynamics (MD) simulation along four crystallographic directions: [0 0 1], [1 1 0], [1 1 1] and [(1) over bar (1) over bar (1) over bar]. The existence of recombination barriers, which allow the formation of metastable defects even below the threshold, has been observed. Displacement cascades produced by both C and Si recoils of energies spanning from 0.5 keV up to, respectively, 5 and 8 keV have also been simulated with MD, both at 300 and 1300 K. Their analysis, together with the analysis of a damage accumulation at 1300 K, reveals that the two sublattices exhibit opposite responses to irradiation: whereas only a little damage is produced on the 'ductile' Si sublattice, many defects accumulate on the much more 'fragile' C sublattice. The low defect mobility in SiC prevents the study of defect evolution within the scope of MD. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Politecn Madrid, Inst Fus Nucl DENIM, Madrid 28006, Spain. Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Div, Livermore, CA 94550 USA. RP Malerba, L (reprint author), Univ Politecn Madrid, Inst Fus Nucl DENIM, C Jose Gutierrez Abascal 2, Madrid 28006, Spain. NR 23 TC 48 Z9 49 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 235 EP 242 DI 10.1016/S0022-3115(99)00183-X PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400025 ER PT J AU Daulton, TL Kirk, MA Rehn, LE AF Daulton, TL Kirk, MA Rehn, LE TI In situ transmission electron microscopy study of ion-irradiated copper: comparison of the temperature dependence of cascade collapse in fcc- and bcc-metals SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab ID DISPLACEMENT CASCADES; MOLECULAR-DYNAMICS; DEFECT CASCADES; CLUSTERS; DAMAGE AB The kinetics which drive cascade formation and subsequent collapse into point-defect clusters are investigated by analyzing the microstructure produced in situ by low fluence 100 keV Kr ion irradiations of fcc-Cu over a wide temperature range (18-873 K). The yield of collapsed point-defect clusters is demonstrated unequivocally to be temperature dependent, remaining approximately constant up to lattice temperatures of 573 K and then abruptly decreasing with increasing temperature. This drop in yield is not caused by defect loss during or following ion irradiation. In addition, this temperature dependence can be explained by a thermal spike effect. These in situ yield measurements are compared to previous ex situ yield measurements in fcc-Ni and bcc-Mo. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Daulton, TL (reprint author), USN, Res Lab, Marine Geosci Div, Stennis Space Ctr, MS 39529 USA. NR 28 TC 9 Z9 9 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 258 EP 268 DI 10.1016/S0022-3115(99)00185-3 PG 11 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400028 ER PT J AU Dai, Y Carsughi, F Sommer, WF Bauer, GS Ullmaier, H AF Dai, Y Carsughi, F Sommer, WF Bauer, GS Ullmaier, H TI Tensile properties and microstructure of martensitic steel DIN 1.4926 after 800 MeV proton irradiation SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT International Workshop on Basic Aspects of Differences in Irradiation Effects Between FCC, BCC and HCP Metals and Alloys CY OCT 15-20, 1998 CL CANGAS DE ONIS, SPAIN SP Fusion Technol Grp Ctr Rech Phys Plasmas Ecolr Polytechn Fed Lausanne, Mat Res Dept Riso Natl Lab, Chem & Mat Sci Div Lawrence Livermore Natl lab AB A double-wall window of martensitic steel DIN 1.4926 (11% Cr) was irradiated with 800 MeV protons in the LANSCE facility of the Los Alamos National Laboratory (LANL) to a total number of about 6.3 x 10(22) protons (2.8 Ah) in a temperature range from 50 degrees C to 230 degrees C. Tensile tests show that irradiation hardening increases with fluence up to the maximum attained dose of about 6.6 dpa. All irradiated specimens show significant embrittlement, less than or equal to 1.5% uniform elongation and 7.5-9% total elongation as compared to about 11% uniform elongation and 21% total elongation for the unirradiated specimens. SEM observations illustrate that the fracture of specimens changes gradually from ductile mode in unirradiated and low dose specimens to cleavage mode in specimens of high dose (greater than or equal to 5.6 dpa). Intergranular brittle fracture mode has not been observed. Irradiation induced small defect clusters exist in all samples of irradiated material. Both of the size and the density of clusters increase with fluence; At the highest dose of 6.6 dpa large dislocation loops of a size greater than or equal to 10 nm have been observed in addition to the clusters. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Paul Scherrer Inst, Spallat Source Div, CH-5232 Villigen, Switzerland. Forschungszentrum Julich, Inst Festkorperforsch, D-52425 Julich, Germany. Los Alamos Natl Lab, APT TPO, Los Alamos, NM 87545 USA. RP Paul Scherrer Inst, Spallat Source Div, CH-5232 Villigen, Switzerland. EM young.dai@psi.ch NR 9 TC 14 Z9 14 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 EI 1873-4820 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 289 EP 294 DI 10.1016/S0022-3115(99)00187-7 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400032 ER PT J AU Almazouzi, A de la Rubia, TD Singh, BN Victoria, M AF Almazouzi, A de la Rubia, TD Singh, BN Victoria, M TI Editors' summary - Basic aspects of differences in irradiation effects between fcc, bcc and hcp metals and alloys SO JOURNAL OF NUCLEAR MATERIALS LA English DT Editorial Material C1 Ecole Polytech Fed Lausanne, CRPP Fus Technol, CH-5232 Villigen, Switzerland. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Riso Natl Lab, Dept Mat Sci, DK-4000 Roskilde, Denmark. RP Almazouzi, A (reprint author), Ecole Polytech Fed Lausanne, CRPP Fus Technol, CH-5232 Villigen, Switzerland. NR 0 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JAN 1 PY 2000 VL 276 BP 295 EP 296 DI 10.1016/S0022-3115(99)00221-4 PG 2 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 270NZ UT WOS:000084543400033 ER PT J AU Patzek, TW De, A AF Patzek, TW De, A TI Lossy transmission line model of hydrofractured well dynamics SO JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING LA English DT Article DE hydrofracture extension; hydrofracture monitoring; hydraulic impedance analysis; electrical transmission line model; Stoneley wave propagation AB The real-time detection of hydrofracture growth is crucial to the successful operation of water, CO2 or steam injection wells in low-permeability reservoirs and to the prevention of subsidence and well failure. In this paper, we describe propagation of very low frequency (1-10 to 100 Hz) Stoneley waves in a fluid-filled wellbore and their interactions with the fundamental wave mode in a vertical hydrofracture. We demonstrate that Stoneley-wave loses energy to the fracture and the energy transfer from the wellbore to the fracture opening is most efficient in soft rocks. We conclude that placing the wave source and receivers beneath the injection packer provides the most efficient means of hydrofracture: monitoring. We then present the lossy transmission line model of wellbore and fracture for the detection and characterization of fracture state and volume. We show that this model captures the wellbore and fracture geometry, the physical properties of injected fluid and the wellbore-fracture system dynamics. The model is then compared with experimentally measured well responses. The simulated responses are in good agreement with published experimental data from several water injection wells with depths ranging from 1000 ft to 9000 ft. Hence, we conclude that the transmission line model of water injectors adequately captures wellbore and fracture dynamics. Using an extensive data set for the South Belridge Diatomite waterfloods, we demonstrate that even for very shallow wells the fracture size and state can be adequately recognized at wellhead. Finally, we simulate the effects of hydrofracture extension on the transient response to a pulse signal generated at wellhead. We show that hydrofracture extensions can indeed be detected by monitoring the wellhead pressure at sufficiently low frequencies. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Patzek, TW (reprint author), Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. NR 21 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-4105 J9 J PETROL SCI ENG JI J. Pet. Sci. Eng. PD JAN PY 2000 VL 25 IS 1-2 BP 59 EP 77 DI 10.1016/S0920-4105(99)00055-8 PG 19 WC Energy & Fuels; Engineering, Petroleum SC Energy & Fuels; Engineering GA 301MB UT WOS:000086313000006 ER PT J AU Cocks, JFC Butler, PA Cann, KJ Greenless, PT Jones, GD Smith, JF Jones, PM Julin, R Juutinen, S Muller, D Piiparinen, M Savelius, A Broda, R Fornal, B Ahmad, I Blumenthal, DJ Carpenter, MP Crowell, B Janssens, RVF Khoo, TL Lauritsen, T Nisius, D Asztalos, S Clark, RM Deleplanque, MA Diamond, RM Fallon, P Lee, IY Macchiavelli, AO MacLeod, RW Stephens, FS Bhattacharyya, P Zhang, CT AF Cocks, JFC Butler, PA Cann, KJ Greenless, PT Jones, GD Smith, JF Jones, PM Julin, R Juutinen, S Muller, D Piiparinen, M Savelius, A Broda, R Fornal, B Ahmad, I Blumenthal, DJ Carpenter, MP Crowell, B Janssens, RVF Khoo, TL Lauritsen, T Nisius, D Asztalos, S Clark, RM Deleplanque, MA Diamond, RM Fallon, P Lee, IY Macchiavelli, AO MacLeod, RW Stephens, FS Bhattacharyya, P Zhang, CT TI Multi-nucleon transfer reactions as a tool for spectroscopy of heavy nuclei SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article ID GAMMA-GAMMA-COINCIDENCES; HIGH-SPIN STATES; ION COLLISIONS; OCTUPOLE SHAPES; ACTINIDE REGION; NEUTRON; POPULATION; ISOTOPES; BEHAVIOR; ISOMERS AB Multi-nucleon transfer reactions have been shown to be an important tool for high-spin spectroscopic studies of Rn, Ra and Th nuclei with N similar or equal to 134. These nuclei have been populated using the heavy-ion collisions of Fe-56 + Th-232, Kr-86 + Th-232 and Xe-136 + Th-232 at beam energies 15-20% above the Coulomb barrier. Excited states with spins as high as 28h have been observed using the latter reaction. Yield distributions of binary-reaction products stopped in thick targets have been derived from the analysis of gamma-gamma and gamma-gamma-gamma coincidence events. These yields indicate that there is significant fission of the target-like reaction products. Intensities deduced for products resulting from neutron transfer or proton transfer appear to be Q-value dependent, while processes involving transfers of several protons and neutrons are governed by mass and charge equilibration. C1 Univ Liverpool, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. Univ Jyvaskyla, Dept Phys, Accelerator Lab, FIN-40351 Jyvaskyla, Finland. H Niewodniczanski Inst Nucl Phys, PL-31342 Krakow, Poland. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. RP Cocks, JFC (reprint author), Vega Grp PLC, 2 Falcon Way, Welwyn Garden City AL7 1TW, Herts, England. RI Carpenter, Michael/E-4287-2015; OI Carpenter, Michael/0000-0002-3237-5734; Butler, Peter/0000-0001-6080-9205 NR 30 TC 15 Z9 15 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD JAN PY 2000 VL 26 IS 1 BP 23 EP 34 PG 12 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 282NF UT WOS:000085224400007 ER PT J AU Cook, MR Graham, C Kavet, R Stevens, RG Davis, S Kheifets, L AF Cook, MR Graham, C Kavet, R Stevens, RG Davis, S Kheifets, L TI Morning urinary assessment of nocturnal melatonin secretion in older women SO JOURNAL OF PINEAL RESEARCH LA English DT Article DE age; breast cancer; melatonin; 6-OHMS; 6-sulfatoxymelatonin ID BREAST-CANCER; PLASMA MELATONIN; METABOLITE; EXCRETION AB We evaluated the feasibility of using morning urine samples in epidemiological studies aimed at clarifying the relationship between nocturnal melatonin levels and breast cancer risk. Initially, a laboratory-based study of 29 women (40-70 yr old) was performed to examine the correlation between plasma melatonin levels in hourly nocturnal blood samples and both melatonin and its major enzymatic metabolite, 6-hydroxymelatonin-sulfate (6-OHMS) in morning urine samples. In a companion field study, morning urine samples were collected from 203 healthy women to assess similarities and differences in laboratory versus field measures. Taken together, our results indicate: 1) levels of melatonin and of creatinine-corrected 6-OHMS in the first morning void urine are strongly correlated with total nocturnal plasma melatonin output (P < 0.001) and also with peak nocturnal melatonin values (P < 0.001); 2) similar ranges for 6-OHMS were found in the laboratory and the field; and 3) neither menopausal status nor hormonal replacement therapy altered 6-OHMS values in morning void urine. The inclusion of morning urine samples in epidemiological studies of cancer could allow cost-effective, widespread testing of the role played by melatonin in human health and disease. C1 Midwest Res Inst, Kansas City, MO 64110 USA. EPRI, Palo Alto, CA USA. Pacific NW Natl Lab, Richland, WA USA. Fred Hutchinson Canc Res Ctr, Seattle, WA 98104 USA. Univ Washington, Sch Publ Hlth & Community Med, Seattle, WA 98195 USA. RP Cook, MR (reprint author), Midwest Res Inst, 425 Volker Blvd, Kansas City, MO 64110 USA. FU NIEHS NIH HHS [ES 07053] NR 17 TC 58 Z9 59 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0742-3098 J9 J PINEAL RES JI J. Pineal Res. PD JAN PY 2000 VL 28 IS 1 BP 41 EP 47 DI 10.1034/j.1600-079x.2000.280106.x PG 7 WC Endocrinology & Metabolism; Neurosciences; Physiology SC Endocrinology & Metabolism; Neurosciences & Neurology; Physiology GA 270XZ UT WOS:000084563600006 PM 10626600 ER PT J AU Kim, MH Phillips, PJ Lin, JS AF Kim, MH Phillips, PJ Lin, JS TI The equilibrium melting points of random ethylene-octene copolymers: A test of the Flory and Sanchez-Eby theories SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE copolymer; crystallization; melting point; polyethylene; defects ID ANGLE X-RAY; POLYETHYLENE; SCATTERING; CRYSTAL AB Ethylene/l-octene copolymers produced with metallocene catalysts are believed to have a homogeneous comonomer content with respect to molecular weight. Two series of copolymers of different molecular weights with a 1-octene content ranging from 0 to 39 branches per 1000 carbon atoms were studied. The influence of branch content on structure and melting behavior as well as on isothermal and nonisothermal bulk crystallization was studied. In this article, the equilibrium melting temperatures of ethylene/l-odene random copolymers is the focus. The principal techniques used were thermal analysis and small-angle X-ray scattering. The use of Hoffman-Weeks plots to obtain the equilibrium melting temperatures of ethylene/l-octene random copolymers resulted in nonsensical high values of the equilibrium melting point or showed behavior parallel to the T-m = T-c line, resulting in no intercept and, hence, an infinite equilibrium melting point. The equilibrium melting temperatures of linear polyethylenes and homogeneous ethylene/l-octene random copolymers were determined as a function of molecular weight and branch content via Thompson-Gibbs plots involving lamellar thickness data obtained from small-angle X-ray scattering. This systematic study made possible the evaluation of two equilibrium melting temperature depression equations for olefin-type random copolymers, the Flory equation and the Sanchez-Eby equation, as a function of defect content and molecular weight. The range over which the two equations could be applied depended on the defect content after correction for the effect of molecular weight on the equilibrium melting temperature. The equilibrium melting temperature, T-m(0)(n, p(B)), of the ethylene/l-octene random copolymers was a function of the molecular weight and defect content for low defect contents (p(B) less than or equal to 1.0%). T-m(0)(n, p(B)) was a weak, function of molecular weight and a strong function of the defect content at a high defect content (p(B) greater than or equal to 1.0%). The Flory copolymer equation could predict T-m(0)(n, p(B)) at p(B) less than or equal to 1.0% when corrections for the effect of molecular weight were made. The Sanchez-Eby uniform inclusion model could predict T-m(0)(n, p(B)) at a high defect content (1.6% less than or equal to p(B) less than or equal to 2.0%). We conclude that some defects were included in the crystalline phase and that the excess free energies (18-37 kJ/mol) estimated in this study were within the theoretical range. (C) 2000 John Wiley & Sons, Inc. C1 Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Phillips, PJ (reprint author), Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. NR 25 TC 43 Z9 43 U1 0 U2 10 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD JAN 1 PY 2000 VL 38 IS 1 BP 154 EP 170 DI 10.1002/(SICI)1099-0488(20000101)38:1<154::AID-POLB19>3.3.CO;2-T PG 17 WC Polymer Science SC Polymer Science GA 263UM UT WOS:000084143700019 ER PT J AU Wang, HL Romero, RJ Mattes, BR Zhu, YT Winokur, MJ AF Wang, HL Romero, RJ Mattes, BR Zhu, YT Winokur, MJ TI Effect of processing conditions on the properties of high molecular weight conductive polyaniline fiber SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE polyaniline; fiber; processing; mechanical; conductivity ID X-RAY; EMERALDINE BASE; FILMS AB Polyaniline-emeraldine base (EB) fiber with excellent mechanical and electrical properties have been spun from highly concentrated (20% w/w), EB/N-methyl-2-pyrrolidinone (NMP)/2-methylaziridine (2 MA) solution. These solutions had gelation times, which varied from hours to days depending on the molar ratio of 2 MA to EB tetramer repeating unit in the N-methyl-2-pyrrolidinone (NMP) solvent. To better compare the mechanical and electrical properties, dense films were also prepared by thermal evaporation of less concentrated solution (1% w/w). Both fibers and films were amenable to thermal stretching with maximum draw ratios of 4 : 1 and these stretched samples exhibited the greatest tensile strength overall. Wide-angle X-ray diffraction (WAXD) of as-spun and 4-times stretched fiber showed a completely amorphous structure. Fiber subjected to heat treatment at 250 degrees C under N-2 flux for 2 h displayed further improvements in mechanical properties because of crosslinking between the polymer chains. Fibers and films were later doped by immersion in a variety of aqueous acid solutions. Room temperature DC conductivities for the doped samples ranged from 6 x 10(-4) to 45 S/cm depending on the specific choice of acid. Scanning electron microscopy of fiber samples shows the presence of macrovoid formation during fiber spinning. Continued refinement of the processing parameters and fiber post-treatment, to enhance chain alignment and increase fiber density, will likely lead to additional improvements in the fiber mechanical and electrical properties. Characterization of emeraldine base (EB) powder, solution, films, and fibers by UV-Vis, DSC, TGA, and WAXD were also performed. (C) 2000 John Wiley & Sons, Inc. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. RP Wang, HL (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, MS J-585, Los Alamos, NM 87545 USA. RI Zhu, Yuntian/B-3021-2008 OI Zhu, Yuntian/0000-0002-5961-7422 NR 29 TC 54 Z9 55 U1 2 U2 16 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD JAN 1 PY 2000 VL 38 IS 1 BP 194 EP 204 DI 10.1002/(SICI)1099-0488(20000101)38:1<194::AID-POLB22>3.0.CO;2-H PG 11 WC Polymer Science SC Polymer Science GA 263UM UT WOS:000084143700022 ER PT J AU Parkhutik, V Chu, Y You, H Nagy, Z Montano, PA AF Parkhutik, V Chu, Y You, H Nagy, Z Montano, PA TI X-ray reflectivity study of formation of multilayer porous anodic oxides of silicon SO JOURNAL OF POROUS MATERIALS LA English DT Article; Proceedings Paper CT 1st International Conference on Porous Semiconductors - Science and Technology (PSST 98) CY MAR 16-20, 1998 CL MALLORCA, SPAIN DE X-ray reflectivity; anodic oxide; oscillations AB Present work reports a study of the morphology of thin (50-600 Angstrom) porous oxides of silicon grown in a special regime of the oscillating anodic potential. X-ray reflectivity (in-situ and ex-situ) was applied to analyze the morphology of oxides. It has been established that there is a direct correlation between a number of oscillations of potential during the oxide growth and the structure of oxide: it has a multi-layer structure with the number of layers corresponding to the number of oscillations. The results are interpreted using the model of the porous structures formation which explains the oscillatory oxide formation kinetics in terms of alternating processes of oxide formation and dissolution. C1 Univ Politecn Valencia, Valencia 46071, Spain. Argonne Natl Lab, MSD, Argonne, IL 60439 USA. RP Univ Politecn Valencia, Valencia 46071, Spain. RI You, Hoydoo/A-6201-2011 OI You, Hoydoo/0000-0003-2996-9483 NR 7 TC 5 Z9 5 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 1380-2224 EI 1573-4854 J9 J POROUS MAT JI J. Porous Mat. PD JAN PY 2000 VL 7 IS 1-3 BP 27 EP 31 DI 10.1023/A:1009679432364 PG 5 WC Chemistry, Applied; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 265QE UT WOS:000084254200005 ER PT J AU Coulthard, I Jiang, DT Zhu, YJ Sham, TK AF Coulthard, I Jiang, DT Zhu, YJ Sham, TK TI A systematic study of synchrotron light induced luminescence from porous silicon: Implications to morphology and chemical effect dependent electronic behaviour SO JOURNAL OF POROUS MATERIALS LA English DT Article; Proceedings Paper CT 1st International Conference on Porous Semiconductors - Science and Technology (PSST 98) CY MAR 16-20, 1998 CL MALLORCA, SPAIN DE porous silicon; photoluminescence; synchrotron radiation ID SITE-SELECTIVE EXAFS; EXCITATION AB Using synchrotron as a tunable excitation source, we have carried out a study on the photoluminescence systematics from a series of porous silicon samples prepared under different conditions, Luminescence spectra were recorded with excitation photon energies tuned to the Si L-3,(2) absorption edge (similar to 100 eV). The luminescence yield was in turn used to monitor the Si L-3,(2)-edge absorption characteristics of porous silicon. A trend of luminescence wavelength and intensity as a function of preparation conditions emerges. Other related observations are also noted. C1 Univ Western Ontario, Dept Chem, London N6A 5B7, England. RP Coulthard, I (reprint author), Argonne Natl Lab, Adv Photon Source, Bld 435, Argonne, IL 60435 USA. NR 15 TC 6 Z9 6 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1380-2224 J9 J POROUS MAT JI J. Porous Mat. PD JAN PY 2000 VL 7 IS 1-3 BP 165 EP 168 DI 10.1023/A:1009618216802 PG 4 WC Chemistry, Applied; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 265QE UT WOS:000084254200033 ER PT J AU Ye, KQ Hamada, M AF Ye, KQ Hamada, M TI Critical values of the lenth method for unreplicated factorial designs SO JOURNAL OF QUALITY TECHNOLOGY LA English DT Article DE confidence intervals; experimentwise error rate; individual error rate; factorial designs; fractional factorial designs; mixed-level designs; Plackett-Burman designs; simulation AB The Lenth method is an objective method for testing effects from unreplicated factorial designs and eliminates the subjectivity in using a half-normal plot. The Lenth statistics are computed for the factorial effects and compared to corresponding critical values. Since the distribution of the Lenth statistics is not mathematically tractable, we propose a simple simulation method to estimate the critical values. Confidence intervals for the estimated critical values can also easily be obtained. Tables of critical values are provided for a large number of designs, and their use is demonstrated with data from three experiments. The proposed method can also be adapted to estimate critical values for other methods. C1 SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ye, KQ (reprint author), SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. NR 11 TC 30 Z9 30 U1 0 U2 4 PU AMER SOC QUALITY CONTROL-ASQC PI MILWAUKEE PA ASQC MEMBERSHIP MANAGER 611 E. WISCONSIN AVENUE, MILWAUKEE, WI 53202 USA SN 0022-4065 J9 J QUAL TECHNOL JI J. Qual. Technol. PD JAN PY 2000 VL 32 IS 1 BP 57 EP 66 PG 10 WC Engineering, Industrial; Operations Research & Management Science; Statistics & Probability SC Engineering; Operations Research & Management Science; Mathematics GA 275LC UT WOS:000084820800009 ER PT J AU Hoffman, DC AF Hoffman, DC TI Glenn Theodore Seaborg: Contributions to nuclear science SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article ID ELEMENTS; CA-48 AB The major contributions of G. T. SEABORG to nuclear science, including co-discovery of many isotopes with practical applications in medicine and industry, co-discovery of plutonium and nine more transuranium elements, the actinide hypothesis, and searches for superheavy elements are briefly summarized. His enduring interest in science education, the history of science, and public affairs are also noted. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94611 USA. Lawrence Berkeley Lab, Div Nucl Sci, Heavy Element Nucl & Radiochem Grp, Berkeley, CA 94611 USA. RP Hoffman, DC (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94611 USA. NR 21 TC 1 Z9 1 U1 2 U2 5 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JAN PY 2000 VL 243 IS 1 BP 7 EP + DI 10.1023/A:1006721124889 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 338JA UT WOS:000088414700002 ER PT J AU Hoffman, DC AF Hoffman, DC TI SuperHeavy elements SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article ID ALPHA-DECAY; NUCLEI; CA-48; ISOTOPES; FUSION AB The long quest to detect SuperHeavy Elements that might exist in nature or to artificially synthesize them at accelerators is briefly reviewed. The very recent reports of the production and detection of the SuperHeavy Elements 114, 116, and 118 at accelerators are discussed. The implications of these discoveries and the prospects for the existence and discovery of additional heavy elements are considered. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94611 USA. Lawrence Berkeley Lab, Div Nucl Sci, Heavy Element Nucl & Radiochem Grp, Berkeley, CA 94611 USA. RP Hoffman, DC (reprint author), Univ Calif Berkeley, Dept Chem, MS-70A-3307, Berkeley, CA 94611 USA. NR 60 TC 3 Z9 3 U1 1 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JAN PY 2000 VL 243 IS 1 BP 13 EP 20 DI 10.1023/A:1006794508959 PG 8 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 338JA UT WOS:000088414700003 ER PT J AU Ceo, RN Thompson, KA AF Ceo, RN Thompson, KA TI Some NDA techniques applied to international safeguards projects SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article AB Recent attention to international safeguards has stimulated interest in nondestructive analysis techniques. These NDA techniques include high and low-resolution gamma-ray spectrometry, active and passive neutron counting, and physical measurements. Often, the NDA measurements are made abroad under field conditions, and in these cases, portability is important. In other cases, the measurements are made under laboratory conditions but no calibration materials are available. This paper describes several NDA applications in support of international safeguards projects, all involving international cooperation. C1 Lockheed Martin Energy Syst Inc, Oak Ridge, TN 37831 USA. RP Ceo, RN (reprint author), Lockheed Martin Energy Syst Inc, Oak Ridge Y-12 Plant, Oak Ridge, TN 37831 USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JAN PY 2000 VL 243 IS 1 BP 39 EP 43 DI 10.1023/A:1006702910776 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 338JA UT WOS:000088414700007 ER PT J AU Firestone, RB AF Firestone, RB TI Nuclear structure and decay data in the electronic age SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article AB The advances made in electronic dissemination of nuclear structure and decay data are described. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Isotopes Project, Berkeley, CA 94720 USA. RP Firestone, RB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Isotopes Project, Berkeley, CA 94720 USA. OI Firestone, Richard/0000-0003-3833-5546 NR 20 TC 2 Z9 2 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JAN PY 2000 VL 243 IS 1 BP 77 EP 86 DI 10.1023/A:1006763113502 PG 10 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 338JA UT WOS:000088414700012 ER PT J AU Hahn, RL AF Hahn, RL TI The physics and radiochemistry of solar neutrino detectors: What have we learned and what can we expect? SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article ID SUPER-KAMIOKANDE; GALLEX; OSCILLATIONS; FLUX AB The situation in solar neutrino science has changed drastically in the past decade, with results now available from five neutrino experiments that use different methods to look at different regions of the solar-neutrino energy-spectrum. While the goal of all of these experiments is physics, they all rely heavily on chemistry and radiochemistry. Three of these experiments are radiochemical, the Cl-37 detector and the two different forms of Ga-71 detectors used in GALLEX and SAGE are based on the chemical isolation and counting of the radioactive products of neutrino interactions. The other two. Kamiokande and its improved successor, Super- Kamiokande, detect neutrinos in real time; however, they also depend sensitively on radiochemistry in that (as in all the solar neutrino detectors) radioactive contaminants must be controlled at very low levels, it is noteworthy that all of these experiments (a) have detected solar neutrinos, but (b) all repel? deficits of the observed neutrinos relative to the predictions of standard solar models - the so-called "solar neutrino problem". In this paper, I review the basic principles of operation of these neutrino detectors, report their recent results, and discuss some of the interpretations that are now in vogue. I then describe some of the new neutrino detectors that are under construction or being developed, and discuss the kinds of new results we might expect to see in the early years of the new millennium. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Hahn, RL (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 35 TC 0 Z9 0 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JAN PY 2000 VL 243 IS 1 BP 93 EP 107 DI 10.1023/A:1006719314411 PG 15 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 338JA UT WOS:000088414700014 ER PT J AU Helmer, RG Gehrke, RJ Davidson, JR Mandler, JW AF Helmer, RG Gehrke, RJ Davidson, JR Mandler, JW TI Scientists, spectrometry, and gamma-ray spectrum catalogues, 1957-2007 SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article AB The original Gamma-ray Spectrum Catalogue, Gc(Li) and Si(Li) Spectrometry published in 1974 by R. L. HEATH has been recreated and enhanced as an electronic file and is available on CD-ROM or over the Internet. This electronic version includes 1998 gamma-ray data from the Evaluated Nuclear Structure Data File database as downloaded in 1998 as well as decay scheme drawings. Future developments of similar catalogues will include gamma-ray spectra from radioactive decay with newer detectors and spectra from neutron interactions with elemental samples and separated isotopes. The electronic form of these catalogues will allow the creation of tutorials on gamma-ray spectrometry and on the data included. C1 Idaho Natl Engn & Environm Lab, Gamma Ray Spectrometry Ctr, Idaho Falls, ID 83415 USA. RP Helmer, RG (reprint author), Idaho Natl Engn & Environm Lab, Gamma Ray Spectrometry Ctr, Idaho Falls, ID 83415 USA. NR 7 TC 10 Z9 10 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JAN PY 2000 VL 243 IS 1 BP 109 EP 117 DI 10.1023/A:1006771315319 PG 9 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 338JA UT WOS:000088414700015 ER PT J AU Mathews, GJ Maronetti, P Salmonson, J Wilson, JR AF Mathews, GJ Maronetti, P Salmonson, J Wilson, JR TI Current topics in gamma-ray astrophysics SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article; Proceedings Paper CT International Workshop on the Applications of High Precision (GAMMA)-Spectroscopy CY JUL 01-03, 1998 CL UNIV NOTRE DAME, NOTRE DAME, IN SP Univ Notre Dame, Grad Sch, Univ Notre Dame, Coll Sci, Univ Notre Dame, Dept Phys HO UNIV NOTRE DAME DE gamma-ray bursts; neutrino bursts; supernovae ID NEUTRON-STAR BINARIES; BURSTS AB This paper reports on recent progress toward unraveling the origin of gamma-ray bursts. It is concluded that neutron-star binaries are one of the few remaining candidates. A model is proposed based upon general relativistic hydrodynamic studies which indicate a new physical. process by which to power a gamma-ray burst. Relativistically driven compression, heating, and collapse of the individual neutron stars can occur many seconds before inspiral and merger. This compression may produce a neutrino burst of similar to 10(53) ergs lasting several seconds. The associated thermal neutrino emission produces an e(+)-e(-) pair plasma by annihilation. We show first results of a simulated burst which produces similar to 10(51) erg in gamma rays of the correct spectral and temporal properties. C1 Univ Notre Dame, Dept Phys 225, Notre Dame, IN 46556 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Mathews, GJ (reprint author), Univ Notre Dame, Dept Phys 225, Nieuwland Sci Hall, Notre Dame, IN 46556 USA. NR 16 TC 0 Z9 0 U1 0 U2 3 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JAN-FEB PY 2000 VL 105 IS 1 BP 97 EP 100 DI 10.6028/jres.105.012 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 309JN UT WOS:000086764900012 PM 27551592 ER PT J AU Lister, CJ AF Lister, CJ TI How far from stability can we go using Gammasphere and the FMA? SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article; Proceedings Paper CT International Workshop on the Applications of High Precision (GAMMA)-Spectroscopy CY JUL 01-03, 1998 CL UNIV NOTRE DAME, NOTRE DAME, IN SP Univ Notre Dame, Grad Sch, Univ Notre Dame, Coll Sci, Univ Notre Dame, Dept Phys HO UNIV NOTRE DAME DE gamma-ray spectroscopy; Gammasphere; heavy-ion reactions ID SHAPE COEXISTENCE; PROTON AB This paper presents new results obtained using the U.S. national gamma-ray facility Gammasphere, which has been operating at the ATLAS accelerator at Argonne National Laboratory since January 1998. Gammasphere was built at Lawrence Berkeley Laboratory and used primarily as a powerful spectrometer for studying nuclei at the highest spins [1]. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Lister, CJ (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 18 TC 4 Z9 4 U1 0 U2 3 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JAN-FEB PY 2000 VL 105 IS 1 BP 137 EP 140 DI 10.6028/jres.105.018 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 309JN UT WOS:000086764900018 PM 27551598 ER PT J AU Garrett, PE Warr, N Yates, SW AF Garrett, PE Warr, N Yates, SW TI Nuclear structure studies with the inelastic neutron scattering reaction and gamma-ray detection SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article; Proceedings Paper CT International Workshop on the Applications of High Precision (GAMMA)-Spectroscopy CY JUL 01-03, 1998 CL UNIV NOTRE DAME, NOTRE DAME, IN SP Univ Notre Dame, Grad Sch, Univ Notre Dame, Coll Sci, Univ Notre Dame, Dept Phys HO UNIV NOTRE DAME DE Doppler-shift attenuation method; gamma gamma-coincidences; inelastic neutron scattering; nuclear structure ID EXCITATIONS; STATES; ER-166; PB-208 AB The (n,n'gamma) reaction has been used at the University of Kentucky accelerator facility to examine the detailed structure of a number of nuclei. The advantages of this method are reviewed, and recent developments are described. Examples of unique nuclear structure studies that have been carried out with this method are presented. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Kentucky, Lexington, KY 40506 USA. RP Garrett, PE (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 14 TC 54 Z9 54 U1 0 U2 4 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JAN-FEB PY 2000 VL 105 IS 1 BP 141 EP 145 DI 10.6028/jres.105.019 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 309JN UT WOS:000086764900019 PM 27551599 ER PT J AU Reynolds, PA Henning, RW Schultz, AJ AF Reynolds, PA Henning, RW Schultz, AJ TI Orientational disordering in CsCo(ND3)(6)(ClO4)(2)Cl-2 crystals studied by single crystal neutron diffraction between 20 and 290 K SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article DE phase transition; orientational disordering; low-temperature neutron diffraction AB A member of the series M(I)M(III)(ND3)(6)(ClO4)(2)X-2, CsCo(ND3)(6) (ClO4)(2)Cl-2, has been examined by single crystal time-of-flight neutron diffraction at 20, T-c-10, T-c + 10, and 290 K, adding to previous X-ray diffraction studies of some compounds in this series. T-c is the phase transition temperature of 250(1)K observed by DSC between closely related simple trigonal structures-twinned ordered R (3) over bar and disordered R (3) over bar m, both with Z = 3 and the former with a = 7.210(2) Angstrom, c = 26.819 Angstrom at 20 K, The twin populations, orientational order parameter, and deuterium disordering are much more clearly observed by neutron than by X-ray diffraction, A simple model involving both twinning and order-disorder with differing ranges of ionic orientational correlations is appropriate for this crystal at all temperatures. This type of subtle transition, sometimes involving anharmonicity, floppy modes, and substantial disorder below the transition temperature, is easily missed by diffraction studies and get the thermal and electrical consequences of such disorder may be severe. (C) 2000 Academic Press. C1 Australian Natl Univ, Res Sch Chem, Canberra, ACT 0200, Australia. Argonne Natl Lab, IPNS, Argonne, IL 60439 USA. RP Reynolds, PA (reprint author), Australian Natl Univ, Res Sch Chem, Canberra, ACT 0200, Australia. NR 16 TC 0 Z9 0 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD JAN PY 2000 VL 149 IS 1 BP 60 EP 67 DI 10.1006/jssc.1999.8496 PG 8 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 282QH UT WOS:000085229200009 ER PT J AU Rard, JA Clegg, SL Palmer, DA AF Rard, JA Clegg, SL Palmer, DA TI Isopiestic determination of the osmotic coefficients of Na2SO4(aq) at 25 and 50 degrees C, and representation with ion-interaction (Pitzer) and mole fraction thermodynamic models SO JOURNAL OF SOLUTION CHEMISTRY LA English DT Review DE isopiestic measurements; sodium sulfate; osmotic coefficient; thermodynamics; Pitzer's model ID ALKALI-METAL SULFATES; MUTUAL DIFFUSION-COEFFICIENTS; AQUEOUS SULFURIC-ACID; SODIUM-SULFATE; HEAT-CAPACITIES; 298.15 K; ELEVATED-TEMPERATURES; MINERAL SOLUBILITIES; HIGH SUPERSATURATION; PHASE-EQUILIBRIA AB Isopiestic vapor-pressure measurements were made for Na2SO4(aq) from 0.11 to 3.74 mol-kg(-1) at 25.00 degrees C and from 0.12 to 3.57 mol-kg(-1) at 50.00 degrees C, using NaCl(aq) as the reference standard. Published isopiestic data, direct vapor pressures, emfs of reversible cells, freezing temperature depressions, boiling temperature elevations, heat capacities, and dilution enthalpies for this system have been critically assessed and recalculated in a consistent manner. Parameters for Fitter's model and a mole fraction-based thermodynamic model were evaluated. The mole fraction-based thermodynamic model for Na2SO4(aq) is valid from the freezing temperatures of the solutions to 150.5 degrees C. Fitter's model represents the osmotic coefficients and emfs essentially to experimental accuracy at 25 and 50 degrees C provided that the third virial coefficient was ionic-strength dependent. C1 Univ Calif Lawrence Livermore Natl Lab, Geosci & Environm Technol Earth & Environm Sci Di, Livermore, CA 94550 USA. Univ E Anglia, Sch Environm Sci, Norwich NR4 7TJ, Norfolk, England. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Rard, JA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Geosci & Environm Technol Earth & Environm Sci Di, Livermore, CA 94550 USA. NR 115 TC 54 Z9 55 U1 0 U2 13 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0095-9782 J9 J SOLUTION CHEM JI J. Solut. Chem. PD JAN PY 2000 VL 29 IS 1 BP 1 EP 49 DI 10.1023/A:1005182316790 PG 49 WC Chemistry, Physical SC Chemistry GA 282TP UT WOS:000085235200001 ER PT J AU Jarzynski, C AF Jarzynski, C TI Hamiltonian derivation of a detailed fluctuation theorem SO JOURNAL OF STATISTICAL PHYSICS LA English DT Article DE fluctuation theorem; irreversible processes ID FREE-ENERGY DIFFERENCES; DYNAMICAL ENSEMBLES; STEADY-STATES; 2ND LAW; NONEQUILIBRIUM MEASUREMENTS; STATISTICAL-MECHANICS; RESPONSE THEORY; EQUILIBRIUM AB We analyze the microscopic evolution of a system undergoing a far-from-equilibrium thermodynamic process. Explicitly accounting for the degrees of freedom of participating heat reservoirs. we derive a hybrid result: similar in form to both the fluctuation theorem and a statement of detailed balance. We relate this result to the steady-state fluctuation theorem and to a ii-re energy relation valid far from equilibrium. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Jarzynski, C (reprint author), Los Alamos Natl Lab, Div Theoret, T-13,MS B288, Los Alamos, NM 87545 USA. EM chrisj@lanl.gov RI Jarzynski, Christopher/B-4490-2009 OI Jarzynski, Christopher/0000-0002-3464-2920 NR 38 TC 164 Z9 165 U1 3 U2 36 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-4715 J9 J STAT PHYS JI J. Stat. Phys. PD JAN PY 2000 VL 98 IS 1-2 BP 77 EP 102 DI 10.1023/A:1018670721277 PG 26 WC Physics, Mathematical SC Physics GA 286LN UT WOS:000085447600004 ER PT J AU Fitzgerald, M Picard, RR Silver, RN AF Fitzgerald, M Picard, RR Silver, RN TI Monte Carlo transition dynamics and variance reduction SO JOURNAL OF STATISTICAL PHYSICS LA English DT Article DE statistical mechanics; variance reduction; Monte Carlo algorithms; Metropolis algorithm; statistical estimators; Ising model; histogram methods; transition probabilities ID HISTOGRAM AB For Metropolis Monte Carlo simulations in statistical physics, efficient, easy-to-implement, and unbiased statistical estimators of thermodynamic properties are based on the transition dynamics. Using an Ising model example, we demonstrate (problem-specific) variance reductions compared to conventional histogram estimators. A proof of variance reduction in a microstate limit is presented. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Fitzgerald, M (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 15 TC 67 Z9 67 U1 0 U2 2 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-4715 J9 J STAT PHYS JI J. Stat. Phys. PD JAN PY 2000 VL 98 IS 1-2 BP 321 EP 345 DI 10.1023/A:1018635108073 PG 25 WC Physics, Mathematical SC Physics GA 286LN UT WOS:000085447600011 ER PT J AU McPherson, A Wang, J Lee, PL Mills, DM AF McPherson, A Wang, J Lee, PL Mills, DM TI A new high-speed beam chopper for time-resolved X-ray studies SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article DE beam choppers; X-rays; timing; phase locking; synchronization ID PULSE LAUE DIFFRACTION; SYNCHROTRON-RADIATION; FEASIBILITY; SILICON; SHUTTER; ESRF AB A new high-speed X-ray beam chopper, which can be phase locked to the temporal structure of the Advanced Photon Source (APS) storage ring, has been developed and tested. The open window time of the chopper is 2450 ns, which corresponds to similar to 67% of the revolution time of the APS storage ring. By phase locking the rotation of the beam chopper to the storage-ring orbital frequency, any portion of the storage-ring fill pattern can be positioned within the beam-chopper transmission-time window. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP McPherson, A (reprint author), Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 18 TC 20 Z9 20 U1 0 U2 6 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD JAN 1 PY 2000 VL 7 BP 1 EP 4 DI 10.1107/S0909049599014582 PN 1 PG 4 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 278PF UT WOS:000084997600001 PM 16609164 ER PT J AU Lee, WK Fernandez, P Mills, DM AF Lee, WK Fernandez, P Mills, DM TI Performance limits of direct cryogenically cooled silicon monochromators - experimental results at the APS SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article DE X-ray optics; high-heat-load optics; cryogenic cooling; silicon monochromators ID THIN AB The successful use of cryogenically cooled silicon monochromators at third-generation synchrotron facilities is well documented. At the Advanced Photon Source (APS) it has been shown that, at 100mA operation with the standard APS undulator A, the cryogenically cooled silicon monochromator performs very well with minimal (< 2 arcsec or no observable thermal distortions. However, to date there has not been any systematic experimental study on the performance limits of this approach. This paper presents experimental results on the performance limits of these directly cooled crystals. The results show that if the beam is limited to the size of the radiation central cone then, at the APS, the crystal will still perform well at twice the present 100 mA single 2.4 m-long 3.3 cm-period undulator heat load. However, the performance would degrade rapidly if a much larger incident white-beam size is utilized. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Lee, WK (reprint author), Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 9 TC 27 Z9 27 U1 1 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD JAN 1 PY 2000 VL 7 BP 12 EP 17 DI 10.1107/S0909049599014478 PN 1 PG 6 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 278PF UT WOS:000084997600003 PM 16609166 ER PT J AU Nakagawa, S Nihei, KT Myer, LR AF Nakagawa, S Nihei, KT Myer, LR TI Stop-pass behavior of acoustic waves in a 1D fractured system SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID STRATIFIED MEDIA; ELASTIC-WAVES; TRANSMISSION; REFLECTION; ANISOTROPY; SLIP AB This study examines the dispersion and the stop-pass band behavior of acoustic waves propagating across periodically spaced and non periodically spaced parallel fractures. Laboratory ultrasonic wave measurements performed on a stack of synthetic fractures (identical steel plates with roughened interfaces) and numerical propagator matrix simulations show spectra with distinct stop-pass band structures that develop with decreasing fracture stiffness. To understand the physics behind these observations, an exact dispersion equation for wave propagation through an infinite series of equally spaced fractures is derived using displacement-discontinuity boundary conditions to model the constitutive behavior of the fractures and Floquet's (Bloch's) theory for the periodic boundary conditions. Both the measured and numerically simulated stop-pass band structures show good agreement with the theoretical predictions. Furthermore, the theory reveals that the left boundary of the stop-bands contains information about the fracture stiffness, suggesting the possibility of determining the stiffness of the parallel fractures from seismic waves. This paper also discusses the effects of fractured systems with random distributions of fracture spacings and stiffnesses on the stop-pass band structures of seismic waves in fractured rock. (C) 2000 Acoustical Society of America. [S0001-4966(00)02801-0]. C1 EO Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Nakagawa, S (reprint author), EO Lawrence Berkeley Natl Lab, Div Earth Sci, 1 Cyclotron Rd,MS 90-1116, Berkeley, CA 94720 USA. RI Nakagawa, Seiji/F-9080-2015; Nihei, Kurt/K-1239-2016 OI Nakagawa, Seiji/0000-0002-9347-0903; NR 18 TC 13 Z9 13 U1 1 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JAN PY 2000 VL 107 IS 1 BP 40 EP 50 DI 10.1121/1.428292 PG 11 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 282NX UT WOS:000085225900003 ER PT J AU Titze, IR Story, BH Burnett, GC Holzrichter, JF Ng, LC Lea, WA AF Titze, IR Story, BH Burnett, GC Holzrichter, JF Ng, LC Lea, WA TI Comparison between electroglottography and electromagnetic glottography SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB Newly. developed glottographic sensors, utilizing high-frequency propagating electromagnetic waves, were compared to a well-established electroglottographic device. The comparison was made on four male subjects under different phonation conditions, including three levels of vocal fold adduction (normal, breathy, and pressed), three different registers (falsetto, chest, and fry), and two different pitches. Agreement between the sensors was always found for the glottal closure event, but for the general wave shape the agreement was better for falsetto and breathy voice than for pressed voice and vocal fry. Differences are attributed to the field patterns of the devices. Whereas the electroglottographic device can operate only in a conduction mode, the electromagnetic device can operate in either the forward scattering (diffraction) mode or in the backward scattering (reflection) mode. Results of our tests favor the diffraction mode because a more favorable angle imposed on receiving the scattered (reflected) signal did not improve the signal strength. Several observations are made on the uses of the electromagnetic sensors for operation without skin contact and possibly in an array configuration for improved spatial resolution within the glottis. (C) 2000 Acoustical Society of America. [S0001-4966(00)06201-9]. C1 Univ Iowa, Dept Speech Pathol & Audiol, Iowa City, IA 52242 USA. Univ Iowa, Natl Ctr Voice & Speech, Iowa City, IA 52242 USA. Denver Ctr Performing Arts, Iowa City, IA 52242 USA. Univ Calif Davis, Dept Appl Sci, Livermore, CA 94557 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94557 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Speech Sci Inst, Apple Valley, MN 55124 USA. RP Titze, IR (reprint author), Univ Iowa, Dept Speech Pathol & Audiol, Iowa City, IA 52242 USA. FU PHS HHS [DO02532] NR 15 TC 7 Z9 9 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JAN PY 2000 VL 107 IS 1 BP 581 EP 588 DI 10.1121/1.428324 PG 8 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 282NX UT WOS:000085225900051 PM 10641666 ER PT J AU Cheong, YS Mukundhan, P Du, HH Withrow, SP AF Cheong, YS Mukundhan, P Du, HH Withrow, SP TI Improved oxidation resistance of silicon nitride by aluminum implantation: I, kinetics and oxide characteristics SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID SINGLE-CRYSTAL SILICON; MOLTEN-SALT CORROSION; SIO2-SI3N4 INTERFACE; SODIUM-SULFATE; CERAMICS; CARBIDE; VAPORS; SI3N4 AB Hot-isostatically-pressed, additive-free Si3N4 ceramics were implanted with aluminum at multi-energies and multidoses to achieve uniform implant concentrations at 1, 5, and 10 at. % to a depth of about 200 nm. The oxidation behavior of unimplanted and aluminum-implanted Si3N4 samples was investigated in 1 atm flowing oxygen entrained with 100 and 220 ppm NaNO3 vapor at 900-1100 degrees C. Unimplanted Si3N4 exhibits a rapid, linear oxidation rate with an apparent activation energy of about 70 kJ/mol, independent of the sodium content in the gas phase. Oxides formed on the unimplanted samples are rough and are populated with cracks and pores. In contrast, aluminum-implanted Si3N4 shows a significantly reduced, parabolic oxidation rate with apparent activation energies in the range of 90-140 kJ/mol, depending on the sodium content as well as the implant concentration. The oxides formed on the implanted samples are glassy and mostly free from surface flaws. The alteration of the oxidation kinetics and mechanism of Si3N4 in a sodium-containing environment by aluminum implantation is a consequence of the effective modification of the properties of the sodium silicates through aluminum incorporation. C1 Stevens Inst Technol, Dept Mat Sci & Engn, Hoboken, NJ 07030 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Cheong, YS (reprint author), Stevens Inst Technol, Dept Mat Sci & Engn, Hoboken, NJ 07030 USA. NR 25 TC 16 Z9 16 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JAN PY 2000 VL 83 IS 1 BP 154 EP 160 DI 10.1111/j.1151-2916.2000.tb01164.x PG 7 WC Materials Science, Ceramics SC Materials Science GA 291XE UT WOS:000085764000023 ER PT J AU Cheong, YS Mukundhan, P Du, HH Withrow, SP AF Cheong, YS Mukundhan, P Du, HH Withrow, SP TI Improved oxidation resistance of silicon nitride by aluminum implantation: II, analysis and optimization SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID TRANSMISSION ELECTRON-MICROSCOPY; MOLTEN-SALT CORROSION; SODIUM-SULFATE; OXIDIZED SI3N4; CERAMICS; GLASSES; CRYSTALS; SPECTRA; RAMAN AB In the preceding paper, it was shown that aluminum ion implantation significantly improves the oxidation resistance of Si3N4 ceramics under the influence of sodium. Not only is the oxidation rate reduced by up to an order of magnitude, the phase and morphological characteristics of the oxides grown on aluminum-implanted samples are improved as well. The role of aluminum in negating the detrimental effect of sodium on the oxidation resistance of Si3N4 ceramics can be interpreted on the basis of network modification of the oxide layers by sodium and aluminum cations. The degree of improvement in the oxidation resistance does not, however, necessarily increase with the aluminum concentration. A simple quantitative analysis is presented which correlates the optimum aluminum implant concentration and the sodium content in the gas phase for the optimization of the oxidation resistance of Si3N4 ceramics. C1 Stevens Inst Technol, Dept Mat Sci & Engn, Hoboken, NJ 07030 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Cheong, YS (reprint author), Stevens Inst Technol, Dept Mat Sci & Engn, Hoboken, NJ 07030 USA. NR 29 TC 9 Z9 9 U1 0 U2 3 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JAN PY 2000 VL 83 IS 1 BP 161 EP 165 DI 10.1111/j.1151-2916.2000.tb01165.x PG 5 WC Materials Science, Ceramics SC Materials Science GA 291XE UT WOS:000085764000024 ER PT J AU Xu, ZK Gupta, SM Viehland, D Yan, YF Pennycook, SJ AF Xu, ZK Gupta, SM Viehland, D Yan, YF Pennycook, SJ TI Direct imaging of atomic ordering in undoped and La-doped Pb(Mg1/3Nb2/3)O-3 SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID LEAD MAGNESIUM NIOBATE; PBMG1/3NB2/3O3; PEROVSKITES; CERAMICS; FERROELECTRICS; CRYSTALS; DISORDER AB In this paper, we report the first direct observations of local ordering in undoped and La-doped Pb(Mg1/3Nb2/3)O-3 (PMN) on an atomic scale by high-resolution (similar to 1.26 Angstrom) Z-contrast imaging. The 1:1 ordering occurs by a variation in the occupancy of Mg and Nb cations between B-I and B-II sublattices. In ordered regions, the B-II sublattice is dominantly occupied by Nb cations, but a small Mg occupancy cannot be excluded. The Mg cations were found to dominantly occupy the B-I sublattice. Within the B-I sublattice, the local Mg/Nb ratio was found to vary among the various B-I sublattices. The results show that the random site model, rather than the space-charge model, is a better structural model for the I:1 ordering observed in PMN. A random distribution of Mg and Nb cations an the BT sublattice within 1:1 ordered regions is believed to be responsible for the relaxer behavior of mixed B-site cation relaxors, such as PMN. C1 Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Xu, ZK (reprint author), Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. OI XU, Zhengkui/0000-0002-7465-8513 NR 31 TC 42 Z9 42 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JAN PY 2000 VL 83 IS 1 BP 181 EP 188 DI 10.1111/j.1151-2916.2000.tb01168.x PG 8 WC Materials Science, Ceramics SC Materials Science GA 291XE UT WOS:000085764000027 ER PT J AU More, KL Tortorelli, PF Ferber, MK Keiser, JR AF More, KL Tortorelli, PF Ferber, MK Keiser, JR TI Observations of accelerated silicon carbide recession by oxidation at high water-vapor pressures SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article AB A study of the exposure of SiC at 1200 degrees C and high water-vapor pressures (1.5 atm) has shown SiC recession rates that exceed what is predicted based on parabolic oxidation at water-vapor pressures of less than or equal to similar to 1 atm. After exposure to these conditions, distinct silica-scale structures are observed; thick, porous, nonprotective cristobalite scales form above a thin, dense silica layer. The porous cristobalite thickens with exposure time, while the thickness of the underlying dense layer remains constant. These observations suggest a moving-boundary phenomenon that is controlled by the rapid conversion of dense vitreous silica to a porous, nonprotective crystalline SiO2. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP More, KL (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Tortorelli, Peter/E-2433-2011; More, Karren/A-8097-2016 OI More, Karren/0000-0001-5223-9097 NR 12 TC 89 Z9 92 U1 3 U2 15 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JAN PY 2000 VL 83 IS 1 BP 211 EP 213 DI 10.1111/j.1151-2916.2000.tb01172.x PG 3 WC Materials Science, Ceramics SC Materials Science GA 291XE UT WOS:000085764000031 ER PT J AU Forslund, DW Smith, RK Culpepper, TC AF Forslund, DW Smith, RK Culpepper, TC TI Federation of the Person Identification Service between enterprises SO JOURNAL OF THE AMERICAN MEDICAL INFORMATICS ASSOCIATION LA English DT Article; Proceedings Paper CT Annual Symposium of the American-Medical-Informatics-Association CY NOV 04-08, 2000 CL LOS ANGELES, CALIFORNIA SP Amer Med Informat Assoc AB The Person Identification Service (RIDS) is, a standard that has been adopted by the Object Management Group(1) for managing identities of persons within a particular domain. That standard includes an interface that supports the ability to connect multiple PIDS servers together in a federated manner. The specification leaves great flexibility as to how to accomplish the federation. In this paper, we examine some of the federated approaches being considered by the Government Computer-based Patient Record Framework (G-CTR) project and discuss their advantages and disadvantages and the details of a specific, scalable approach to federation. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. GCPR MPI IPT Lead, Mclean, VA USA. 2AB Inc, CORBAmedTM, Calera, AL 35040 USA. RP Forslund, DW (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU HANLEY & BELFUS INC PI PHILADELPHIA PA 210 S 13TH ST, PHILADELPHIA, PA 19107 USA SN 1067-5027 J9 J AM MED INFORM ASSN JI J. Am. Med. Inf. Assoc. PY 2000 SU S BP 240 EP 244 PG 5 WC Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Information Science & Library Science; Medical Informatics SC Computer Science; Information Science & Library Science; Medical Informatics GA 458RC UT WOS:000170207500050 ER PT J AU Spyropoulos, B Batistatos, D Glotsos, D Marneris, I AF Spyropoulos, B Batistatos, D Glotsos, D Marneris, I TI An information system supporting electromagnetic compatibility and radiation risk management in the modern hospital SO JOURNAL OF THE AMERICAN MEDICAL INFORMATICS ASSOCIATION LA English DT Meeting Abstract C1 Inst Educ Technol, Med Instrumentat Technol Dept, Athens, Greece. BNL, Upton, NY USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU HANLEY & BELFUS INC PI PHILADELPHIA PA 210 S 13TH ST, PHILADELPHIA, PA 19107 USA SN 1067-5027 J9 J AM MED INFORM ASSN JI J. Am. Med. Inf. Assoc. PY 2000 SU S BP 1139 EP 1139 PG 1 WC Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Information Science & Library Science; Medical Informatics SC Computer Science; Information Science & Library Science; Medical Informatics GA 458RC UT WOS:000170207500390 ER PT J AU Belov, ME Gorshkov, MV Udseth, HR Anderson, GA Tolmachev, AV Prior, DC Harkewicz, R Smith, RD AF Belov, ME Gorshkov, MV Udseth, HR Anderson, GA Tolmachev, AV Prior, DC Harkewicz, R Smith, RD TI Initial implementation of an electrodynamic ion funnel with Fourier transform ion cyclotron resonance mass spectrometry SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article AB Fourier transform ion cyclotron resonance (FTICR) mass spectrometry has become a widely used method to study biopolymers. The method, in combination with an electrospray ionization (ESI) source has demonstrated the highest resolution and accuracy yet achieved for characterization of biomolecules and their noncovalent complexes. The most common design for the ESI interface includes a heated capillary inlet followed by a skimmer having a small orifice to limit gas conductance between a higher pressure (1 to 5 torr) source region and the lower pressure ion guide. The ion losses in the capillary-skimmer interface are large (estimated to be more than 90%) and thus reduce achievable sensitivity. Ln this work, we report on the initial implementation of a newly developed electrodynamic ion funnel in a 3.5 tesla ESI-FTICR mass spectrometer. The initial results show dramatically improved ion transmission as compared to the conventional capillary-skimmer arrangement. An estimated detection limit of 30 zeptomoles (similar to 18,000 molecules) has been achieved for the analysis of the proteins with molecular weights ranging from 8 to 20 kDa. (J Am Soc Mass Spectrom 2000, 11, 19-23) (C) 2000 American Society for Mass Spectrometry. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999,MS-K8-98, Richland, WA 99352 USA. RI Gorshkov, Mikhail/E-8522-2010; Smith, Richard/J-3664-2012; Gorshkov, Mikhail/N-4984-2013 OI Smith, Richard/0000-0002-2381-2349; Gorshkov, Mikhail/0000-0001-9572-3452 FU NCRR NIH HHS [RR12365] NR 8 TC 68 Z9 71 U1 1 U2 12 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD JAN PY 2000 VL 11 IS 1 BP 19 EP 23 DI 10.1016/S1044-0305(99)00121-X PG 5 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 266XM UT WOS:000084325600003 PM 10631660 ER PT J AU Groenewold, GS Appelhans, AD Gresham, GL Olson, JE Jeffery, M Weibel, M AF Groenewold, GS Appelhans, AD Gresham, GL Olson, JE Jeffery, M Weibel, M TI Characterization of VX on concrete using ion trap secondary ionization mass spectrometry SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID CHEMICAL WARFARE AGENTS; SUPERCRITICAL FLUID EXTRACTION; CAPILLARY GAS-CHROMATOGRAPHY; STATIC SIMS; TRIBUTYL-PHOSPHATE; SOIL; SURFACES; DEGRADATION; PROSPECTS; PRODUCTS AB The nerve agent VX (O-ethyl S-2-diisopropylaminoethyl methyl phosphonothiolate) was analyzed on the surface of concrete samples using an ion trap secondary ion mass spectrometer (IT-SIMS). It was found that VX could be detected down to an absolute quantity of 5 ng on a concrete chip, or to a surface coverage of 0.0004 monolayers on crushed concrete. To achieve these levels of detection, the m/z 268 --> 128 ion fragmentation was measured using MS2, where mit 268 corresponds to [VX + H](+), and 128 corresponds to a diisopropylvinylammonium isomer, that is formed by the elimination of the phosphonothiolate moiety. Detection at these levels was accomplished by analyzing samples that had been recently exposed to VX, i.e., within an hour. When the VX-exposed concrete samples were aged, the SIMS signature for intact VX had disappeared, which signaled the degradation of the compound on the concrete surface. The VX signature was replaced by ions which are interpreted in terms of VX degradation products, which appear to be somewhat long lived on the concrete surface. These compounds include ethylmethylphosphonic acid (EMPA), diisopropyl taurine (DIPT), diisopropylaminoethanethiol (DESH), bis(diisopropylaminoethane)disulfide [(DES)(2)], and a particularly tenacious compound that may correspond to diisopropylvinylamine (DNA), or an isomer thereof. It was found that the thiolamine-derived degradation products DIPT, DESH, and (DES)(2) were removed with isopropyl alcohol extraction. However, the DIVA-related degradation product was observed to strongly adhere to the concrete surface for longer than one week. Although quantitation was not possible in this set of experiments, the results clearly show the rapid degradation of VX on concrete, as well as the surface sensitivity of the IT-SIMS for intact VX and its adsorptive degradation products. (J Am Soc Mass Spectrom 2000, 11, 69-77) (C) 2000 American Society for Mass Spectrometry. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. W Desert Test Ctr, Battelle Dugway Operat, Dugway, UT USA. RP Groenewold, GS (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. NR 32 TC 39 Z9 40 U1 0 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD JAN PY 2000 VL 11 IS 1 BP 69 EP 77 DI 10.1016/S1044-0305(99)00118-X PG 9 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 266XM UT WOS:000084325600009 PM 10631666 ER PT J AU Veenstra, TD Martinovic, S Anderson, GA Pasa-Tolic, L Smith, RD AF Veenstra, TD Martinovic, S Anderson, GA Pasa-Tolic, L Smith, RD TI Proteome analysis using selective incorporation of isotopically labeled amino acids SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID ESCHERICHIA-COLI K-12; MASS-SPECTROMETRY; PROTEINS; LYSOZYME; GENOME AB A method is described for identifying intact proteins from genomic databases using a combination of accurate molecular mass measurements and partial amino acid content. An initial demonstration was conducted for proteins isolated from Escherichia coli (E. coli) using a multiple auxotrophic strain of K12. proteins extracted from the organism grown in natural isotopic abundance minimal medium and also minimal medium containing isotopically labeled leucine (Leu-D-10), were mixed and analyzed by capillary isoelectric focusing (CIEF) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FTICR). The incorporation of the isotopically labeled Leu residue has no effect on the CIEF separation of the protein, therefore both versions of the protein are observed within the same FTICR spectrum. The difference in the molecular mass of the natural isotopic abundance and Leu-D-10 isotopically labeled proteins is used to determine the number of Leu residues present in that particular protein. Knowledge of the molecular mass and number of Leu residues present can be used to unambiguously identify the intact protein. Preliminary results show the efficacy of this method for unambiguously identifying proteins isolated from E. coli. (J Am Soc Mass Spectrom 2000, 11, 78-82) (C) 2000 American Society far Mass Spectrometry. C1 Pacific NW Lab, Environm & Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Lab, Environm & Mol Sci Lab, POB 999,MSIN-K8-98, Richland, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 19 TC 115 Z9 117 U1 0 U2 4 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD JAN PY 2000 VL 11 IS 1 BP 78 EP 82 DI 10.1016/S1044-0305(99)00120-8 PG 5 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 266XM UT WOS:000084325600010 PM 10631667 ER PT J AU Feng, BB Smith, RD AF Feng, BB Smith, RD TI A simple nanoelectrospray arrangement with controllable flowrate for mass analysis of submicroliter protein samples SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID CAPILLARY ZONE ELECTROPHORESIS; FUSED-SILICA CAPILLARIES; ELECTROSPRAY-IONIZATION; NANO-ELECTROSPRAY; MICROFABRICATED DEVICE; CYLINDRICAL CAPACITOR; POLYACRYLAMIDE GELS; ION-SOURCE; SPECTROMETRY; INTERFACE AB A simple arrangement for nanoelectrospray ionization using a conventional syringe pump connected to a pulled unmodified capillary has been evaluated. This arrangement avoids several disadvantages associated with metal-coated nanoelectrospray emitters. The relatively large orifice (similar to 9 mu m) at the pulled capillary tip reduces sample clogging and the use of the pump minimizes spray disruption due to gas bubbles. Subattomole detection Limit was achieved with nanomolar protein sample solutions at 5-10 nL/min flowrates using an LCQ mass spectrometer. Submicroliter samples can be loaded from the tip orifice and stored inside the capillary to virtually eliminate any dead volume, and then be electrosprayed for extended periods at well-controlled flowrates. (J Am Soc Mass Spectrom 2000, 11, 94-99) (C) 2000 American Society for Mass Spectrometry. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. EM rd_smith@pnl.gov RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 39 TC 17 Z9 18 U1 2 U2 8 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD JAN PY 2000 VL 11 IS 1 BP 94 EP 99 DI 10.1016/S1044-0305(99)00124-5 PG 6 WC Biochemical Research Methods; Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Biochemistry & Molecular Biology; Chemistry; Spectroscopy GA 266XM UT WOS:000084325600013 PM 10631670 ER PT J AU Schaub, H Vadali, SR Junkins, JL Alfriend, KT AF Schaub, H Vadali, SR Junkins, JL Alfriend, KT TI Spacecraft formation flying control using mean orbit elements SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article; Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 16-19, 1999 CL GIRDWOOD, ALASKA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut ID SATELLITES AB Two nonlinear feedback control laws are presented for reestablishing a desired J(2) invariant relative orbit. Since it is convenient to describe the relative orbit of a deputy with respect to a chief satellite in terms of mean orbit element differences, and because the conditions for a relative orbit being J(2) invariant are expressed in terms of mean orbit elements, the first control law feeds back errors in terms of mean orbit elements. Dealing with mean orbit elements has the advantage that short period oscillations are not perceived as tracking errors; rather, only the long term tracking errors are compensated for. The second control law feeds back traditional Cartesian position and velocity tracking errors. For both of the control laws, the desired orbit is computed using mean orbit elements. A numerical study compares and contrasts the two feedback laws. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Texas A&M Univ, Dept Aerosp Engn, College Stn, TX 77843 USA. RP Schaub, H (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 15 TC 116 Z9 131 U1 4 U2 15 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 USA SN 0021-9142 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD JAN-MAR PY 2000 VL 48 IS 1 BP 69 EP 87 PG 19 WC Engineering, Aerospace SC Engineering GA 406CE UT WOS:000167196700004 ER PT J AU Morss, LR Nash, KL Ensor, DD AF Morss, LR Nash, KL Ensor, DD TI Thermodynamics of lanthanide and uranyl complexes with tetrahydrofuran-2,3,4,5-tetracarboxylic acid (THFTCA) SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID ACTINIDES AB We present the results of an investigation of the thermochemistry of the complexation of La3+, Nd3+, Eu3+, Dy3+, Tm3+, and UO22+ by tetrahydrofuran-2,3,4,5-tetracarboxylic acid (THFTCA). This predisposed structural analog to oxydiacetic acid (ODA) has been previously shown both to exhibit greater sensitivity to lanthanide cation radius than complexes with the unconstrained ODA and to form anomalously weak complexes with UO22+. Our purpose is to interpret these observations in terms of the balance between enthalpy and entropy contributions to the overall complexation thermodynamics. Enthalpies have been calculated from titration calorimetry experiments both for the protonation of the free ligand and for the formation of selected 1:1 and 1:2 complexes in pH 2-3 acidic media (I=0.1 M). The complexation entropies for the lanthanide complexes have been calculated using the previously reported stability constants for the MH2L+, MHL, and M(H2L)(2-). The stability constants for the uranyl complexes have been determined by potentiometric titration and these values used to calculate the thermodynamic parameters. Complexation enthalpies for the 1:1 lanthanide-THFTCA complexes (MH2L+ species) are nearly identical to those of the lanthanide ODA complexes. Therefore, the size-selectivity observed in the lanthanide-THFTCA complexes arises from the complexation entropy. The comparative weakness of the uranyl complexes with THFTCA also is accounted for thermodynamically in the entropy term. Calculations based on an electrostatic model for complexation entropy and molecular mechanics modeling are used to help interpret the experimental results. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Tennessee Technol Univ, Dept Chem, Cookeville, TN 38505 USA. RP Nash, KL (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 24 TC 13 Z9 13 U1 0 U2 0 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0300-9246 J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PY 2000 IS 3 BP 285 EP 291 DI 10.1039/a906729i PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 277WE UT WOS:000084955900012 ER PT J AU Senge, MO Renner, MW Kalisch, WW Fajer, J AF Senge, MO Renner, MW Kalisch, WW Fajer, J TI Molecular structure of (5,10,15,20-tetrabutyl-2,3,7,8,12,13,17,18-octaethylporphyrinato)nickel( II)-correlation of nonplanarity with frontier orbital shifts SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID ABSORPTION FINE-STRUCTURE; DIFFERENTIAL-OVERLAP TECHNIQUE; PHOTOSYNTHETIC REACTION-CENTER; INTERMEDIATE NEGLECT; CONFORMATIONAL FLEXIBILITY; PHOTOPHYSICAL PROPERTIES; CRYSTAL-STRUCTURE; REDOX POTENTIALS; METAL-COMPLEXES; PORPHYRINS AB Highly substituted porphyrins exhibit significantly distorted, nonplanar conformations in the solid state. The crystallographically determined degree of nonplanarity correlates with a bathochromic shift of the absorption maxima in solution. In addition, nonplanar porphyrins with meso aryl groups show increasing in-plane rotation of the meso aryl groups, which potentially could account for the observed changes in spectroscopic and physicochemical properties of nonplanar porphyrins. A crystal structure analysis of the title compound NiTBuOEP reveals a highly nonplanar conformation with an average deviation from planarity for the 24 macrocycle atoms of 0.462 Angstrom and displacements of the meso carbon atoms from the 4N-plane of 1.044 Angstrom. The average Ni-N bond distance in the crystal (1.873(3) Angstrom) is in good agreement with the Ni-N bond distance in solution (1.87 Angstrom) that was determined by EXAFS. Compared to more planar reference compounds, NiTBuOEP exhibits significantly red-shifted absorption spectra in solution, correctly predicted by INDO/s calculations. As the shortness of the Ni-N bonds has been shown to be an excellent indicator for the degree of conformational distortion in porphyrins, this proves that the highly nonplanar conformation of sterically strained porphyrins is maintained in solution. Thus, the physical and chemical properties measured in solution do indeed reflect the stereochemistry of the single crystals. In addition, the use of only alkyl substituents in NiTBuOEP to cause nonplanarity obviously circumvents potential electronic effects due to aryl ring interactions. C1 Free Univ Berlin, Inst Chem, D-14195 Berlin, Germany. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Senge, MO (reprint author), Free Univ Berlin, Inst Chem, Takustr 3, D-14195 Berlin, Germany. RI Senge, Mathias/F-1504-2011 OI Senge, Mathias/0000-0002-7467-1654 NR 60 TC 58 Z9 58 U1 2 U2 5 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0300-9246 J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PY 2000 IS 3 BP 381 EP 385 DI 10.1039/a905927j PG 5 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 277WE UT WOS:000084955900025 ER PT J AU Rulkens, R Coles, MP Tilley, TD AF Rulkens, R Coles, MP Tilley, TD TI Synthesis and structure of the (tetrahydroxy)oligosiloxane [((BuO)-Bu-t)(3)SiOSi(OH)(2)](2)O SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID RAY CRYSTAL-STRUCTURE; STABLE SILANETRIOLS; SILICA SURFACES; OXIDE CATALYSTS; BUILDING-BLOCKS; METAL-OXIDES; COMPLEXES; MODEL; TETRAHYDROXYDISILOXANE; REACTIVITY AB The solid-state structure of the (tetrahydroxy)oligosiloxane [((BuO)-Bu-t)(3)SiOSi(OH)(2)](2)O, synthesized by the hydrolysis of ((BuO)-Bu-t)(3)SiOSiCl3, reveals molecules composed of four vertex-linked SiO4 tetrahedra and containing four SiOH groups involved in both intermolecular and intramolecular hydrogen-bonding. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Tilley, TD (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 40 TC 8 Z9 8 U1 0 U2 1 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0300-9246 J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PY 2000 IS 5 BP 627 EP 628 DI 10.1039/b000322k PG 2 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 287TZ UT WOS:000085523700001 ER PT J AU Kesanli, B Gardner, DR Scott, B Eichhorn, BW AF Kesanli, B Gardner, DR Scott, B Eichhorn, BW TI Two new bimetallic phosphido carbonyl complexes of nickel(0): [Ni-2(CO)(2)(PPh3)(2)(mu-CO)(mu-PPh2)](-) and [Ni-2(CO)(4)(mu-PPh2)(2)](2-) SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID RAY CRYSTAL-STRUCTURES; DIPHOSPHENE COMPLEXES; NI-NI; NI2(MU-TERT-BU2P)2(CO)3; SUBSTITUTION; LIGANDS AB Toluene solutions of Ni(CO)(2)(PPh3)(2) react with excess potassium metal to give the [Ni-2(CO)(4)(mu-PPh2)(2)](2-) ion (2) which contains two tetrahedral Ni centers fused along a common edge. Each Ni achieves an 18 electron configuration without the formation of a Ni-Ni bond (d(Ni-Ni) = 3.397(1) Angstrom) in contrast to the two-electron oxidation product, Ni-2(CO)(4)(mu-PPh2)(2) (1) (d(Ni-Ni) = 2.510(2) Angstrom). The anion 2 shows a reversible oxidation at -1.5 V and a quasi-reversible oxidation at -1.1 V vs. FeCp2/FeCp2+. The negative ion electrospray mass spectrum of 2 shows the one-electron oxidation product of 2, [Ni-2(CO)(4)(mu-PPh2)(2)](-), along with three decarbonylation products [Ni-2(CO)(3)(mu-PPh2)(2)](-), [Ni-2(CO)(2)(mu-PPh2)(2)](-), and [Ni-2(CO)(mu-PPh2)(2)](-) where [Ni-2(CO)(3)(mu-PPh2)(2)](-) is the base peak. Ethylenediamine solutions of Sn-9(4-) react with Ni(CO)(2)(PPh3)(2) in the presence of 2,2,2-crypt (4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane) to reproducibly give [Ni-2(CO)(2)(PPh3)(2)(mu-CO)(mu-PPh2)](-) (3), as one of three products. The anion 3 also has an edge-shared bitetrahedral geometry but, unlike 2, possesses a Ni-Ni bond (d(Ni-Ni) = 2.4930(9) Angstrom). C1 Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Eichhorn, BW (reprint author), Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. RI Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 31 TC 6 Z9 6 U1 0 U2 3 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0300-9246 J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PY 2000 IS 8 BP 1291 EP 1296 DI 10.1039/b000852o PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 301TD UT WOS:000086325600013 ER PT J AU Clark, DL Donohoe, RJ Gordon, JC Gordon, PL Keogh, DW Scott, BL Tait, CD Watkin, JG AF Clark, DL Donohoe, RJ Gordon, JC Gordon, PL Keogh, DW Scott, BL Tait, CD Watkin, JG TI First single-crystal X-ray diffraction study of a lanthanide tricarbonate complex: [Co(NH3)(6)][Sm(CO3)(3)(H2O)]center dot 4H(2)O SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID CARBONATE COMPLEXATION; RARE-EARTH; IDENTIFICATION; BURBANKITE; NEPTUNIUM; SYSTEM; RAMAN; EXAFS AB The first single-crystal X-ray diffraction study of a lanthanide tricarbonate complex, namely [Co(NH3)(6)][Sm(CO3)(3)(H2O)]. 4H(2)O, is reported and reveals a zigzag chain structure of 9-coordinate samarium metal centers bridged by mu-eta(2):eta(1) carbonate ligands. C1 Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Glenn T Seaborg Inst Transactinium Sci, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Biosci, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Keogh, DW (reprint author), Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Glenn T Seaborg Inst Transactinium Sci, Mail Stop J514,NMT DO, Los Alamos, NM 87545 USA. RI Clark, David/A-9729-2011; Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 40 TC 4 Z9 4 U1 0 U2 9 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1470-479X J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PY 2000 IS 13 BP 1975 EP 1977 DI 10.1039/b000778l PG 3 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 344KY UT WOS:000088758500004 ER PT J AU Jensen, MP Beitz, JV Rogers, RD Nash, KL AF Jensen, MP Beitz, JV Rogers, RD Nash, KL TI Thermodynamics and hydration of the europium complexes of a nitrogen heterocycle methane-1,1-diphosphonic acid SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID SUBSTITUTED DIPHOSPHONIC ACIDS; 1-HYDROXYETHANE-1,1-DIPHOSPHONIC ACID; AQUEOUS-SOLUTION; LUMINESCENCE LIFETIMES; STABILITY-CONSTANTS; DICARBOXYLIC-ACIDS; CRYSTAL-STRUCTURE; METAL EXTRACTION; ION; SOLVENT AB The enthalpies for formation of five Eu3+ complexes with N-piperidinomethane-1,1-diphosphonic acid (H(4)pmdp) have been determined by titration calorimetry in 2 M (Na,H)ClO4 media at 25 degrees C. Both protonation enthalpies and entropies, and the structure of H(4)pmdp in the solid state indicate protonation of the piperidine nitrogen to give a zwitterion in the free ligand. Luminescent lifetime measurements show that the formation of the 1:1 and 1:2 Eu:L complexes of a variety of methane-1,1-diphosphonic acids liberates an average of 3.3 +/- 0.1 water molecules per ligand from the Eu inner hydration sphere. The number of water molecules in the inner coordination sphere and the thermodynamic parameters of the complexes suggest that the structure of the Eu3+-pmdp complexes and the strength of the Eu3+-pmdp bonds are similar to those of other methane-1,1-diphosphonic acids despite the presence of the piperidine ring. However, the complexation entropies argue for weaker solvation of the Eu-pmdp complexes probably due to the hydrophobic character of the piperidine ring. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Univ Alabama, Dept Chem, Tuscaloosa, AL 35487 USA. RP Jensen, MP (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Rogers, Robin/C-8265-2013; Jensen, Mark/G-9131-2012 OI Rogers, Robin/0000-0001-9843-7494; Jensen, Mark/0000-0003-4494-6693 NR 56 TC 20 Z9 20 U1 0 U2 4 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1470-479X J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PY 2000 IS 18 BP 3058 EP 3064 DI 10.1039/b004038j PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 351QT UT WOS:000089170200004 ER PT J AU Brooker, S Caygill, GB Croucher, PD Davidson, TC Clive, DLJ Magnuson, SR Cramer, SP Ralston, CY AF Brooker, S Caygill, GB Croucher, PD Davidson, TC Clive, DLJ Magnuson, SR Cramer, SP Ralston, CY TI Conversion of some substituted phenols to the corresponding masked thiophenols, synthesis of a dinickel(II) dithiolate macrocyclic complex and isolation of some metal- and ligand-based oxidation products SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID BINUCLEAR COPPER(II) COMPLEXES; OCTAHEDRAL NICKEL(II) IONS; STRUCTURAL CHARACTERIZATION; DESULFOVIBRIO-GIGAS; CRYSTAL-STRUCTURE; REDOX POTENTIALS; IRON HYDROGENASE; SQUARE-PLANAR; SITE; SULFUR AB A modified preparation of the masked thiolate head unit S-(2,6-diformyl-4-methylphenyl) dimethylthiocarbamate 6 is detailed and two new masked thiolate head units, S-(2,6-diformyl-4-tert-butylphenyl) dimethylthiocarbamate 7 and S-(2-formylphenyl) dimethylthiocarbamate 8, are prepared by this method. The synthesis, crystal structure, NMR spectra and electrochemical properties of the first macrocyclic complex to be derived from 7, [Ni(2)L1](ClO4)(2), are discussed. Oxidation of [Ni(2)L2](CF3SO3)(2) (L2(2-) is derived from 6 and 1,3-diaminopropane) with cerium(IV) ammonium nitrate led to the precipitation of the black complex [Ni(2)L2][Ce(NO3)(6)], which is believed to contain a single nickel(III) centre. This complex decomposes in DMF over time (approximate to 24 hours) to form the red dinickel(II) complex [Ni(2)L2](NO3)(2). 2DMF which has been structurally characterised. Oxidation of [Ni(2)L3](CF3SO3)(2) (L3(2-) is derived from 6 and 1,4-diaminobutane) with I-2 results in ligand oxidation forming the metal free macrocycle (L3')(2+) which contains two five membered isothiazole rings. This is confirmed by the X-ray crystal structure determinations of (L3')(I-3)(2) and (L3')(I)(2)(I-2)(5). C1 Univ Otago, Dept Chem, Dunedin, New Zealand. Univ Alberta, Dept Chem, Edmonton, AB T6G 2G2, Canada. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Energy & Environm, Berkeley, CA 94720 USA. RP Univ Otago, Dept Chem, POB 56, Dunedin, New Zealand. EM sbrooker@alkali.otago.ac.nz RI Brooker, Sally/C-3440-2016 OI Brooker, Sally/0000-0002-5878-8238 NR 75 TC 37 Z9 38 U1 0 U2 1 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1472-7773 J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PY 2000 IS 18 BP 3113 EP 3121 DI 10.1039/b004214p PG 9 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 351QT UT WOS:000089170200012 ER PT J AU Giesbrecht, GR Gebauer, A Shafir, A Arnold, J AF Giesbrecht, GR Gebauer, A Shafir, A Arnold, J TI Alkali-metal complexes of a triazacyclononane-functionalized tetramethylcyclopentadienyl ligand SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID OLEFIN POLYMERIZATION; CATALYSTS; DERIVATIVES; TRIDENTATE AB Reaction of (1,4-diisopropyl-1,4,7-triazacyclononane)Li with C5Me4HSiMe2Cl yields the new donor-functionalized ligand, [C5Me4SiMe2(tacn)]H; the alkali-metal salts [C5Me4SiMe2(tacn)]M (M=Li, Na, K) are obtained upon reaction with BuLi, NaN(SiMe3)(2) or KN(SiMe3)(2). C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Arnold, J (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Shafir, Alexandr/D-1676-2009; Arnold, John/F-3963-2012 OI Shafir, Alexandr/0000-0002-8127-2299; Arnold, John/0000-0001-9671-227X NR 21 TC 16 Z9 16 U1 0 U2 3 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1470-479X J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PY 2000 IS 22 BP 4018 EP 4020 DI 10.1039/b007075k PG 3 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 374EC UT WOS:000165330600006 ER PT J AU Myers, SA Assink, RA Loy, DA Shea, KJ AF Myers, SA Assink, RA Loy, DA Shea, KJ TI Investigation of the transmission of substituent effects by Si-29 NMR SO JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2 LA English DT Article ID MODIFIED SILICA SOLS; CONDENSATION; HYDROLYSIS; KINETICS; POLYCONDENSATION; POLYMERS; MODEL; GELS AB Long range substituent effects on the Si-29 NMR chemical shifts in a series of alkylene- and arylene-bridged triethoxysilanes were observed over as many as 11 bonds. The hydrolysis reaction of an ethoxide caused the resonance of the silicon on the opposing end of the bridging unit to move downfield. The alkylene bridging units ranged from ethylene to octylene while the arylene bridging units included phenyl and biphenyl. Resonance assignments were confirmed by the absence of these shifts for the triethoxysilyl in 1-triphenylsilyl-2-triethoxysilylethane. The magnitude of the downfield shift decreased as the length of the bridging unit between silicon atoms increased. Transmission of the substituent effect along a polymethylene chain was successfully modeled by a through-bond mechanism with an attenuation factor of 1.88 for each methylene unit. C1 Sandia Natl Labs, Org 1812, Albuquerque, NM 87185 USA. USN, Air Warfare Ctr, China Lake, CA 93555 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92717 USA. RP Sandia Natl Labs, Org 1812, POB 5800, Albuquerque, NM 87185 USA. RI Loy, Douglas/D-4847-2009 OI Loy, Douglas/0000-0001-7635-9958 NR 33 TC 8 Z9 8 U1 0 U2 10 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1472-779X J9 J CHEM SOC PERK T 2 JI J. Chem. Soc.-Perkin Trans. 2 PY 2000 IS 3 BP 545 EP 549 DI 10.1039/a906569e PG 5 WC Chemistry, Organic; Chemistry, Physical SC Chemistry GA 290NV UT WOS:000085683000022 ER PT J AU Lee, HS Sun, X Yang, XQ McBreen, J Callahan, JH Choi, LS AF Lee, HS Sun, X Yang, XQ McBreen, J Callahan, JH Choi, LS TI Synthesis of cyclic aza-ether compounds and studies of their use as anion receptors in nonaqueous lithium halide salts solution SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article AB A series of new anion receptors, based on cyclic aza-ether compounds, have been synthesized. The synthesis and characterization of these compounds are described. In all these cyclic aza-ether compounds, the electron-withdrawing group CF3SO2 was attached to each of the nitrogen atoms. Each member of this class of compounds contains a different number of nitrogen atoms. When used as additives, all of them can significantly increase the ionic conductivity of lithium halide salts in tetrahydrofuran solutions due to the ion-pair dissociation effect. This ion-pair dissociation effect is a result of complexation between these compounds and the halide anions. Ionic conductivity studies show that the complexation behavior is related to both the ring structure of the cyclic compounds and the characteristics of the halide anions. X-ray diffraction data show that the diffraction patterns of the complex crystals grown from cosolution of the cyclic aza-ether compound and lithium halide salts are completely different than those from the pure cyclic aza-ether compounds. New Bragg peaks representing a large d-spacing (similar to 15 Angstrom) are observed for the complex crystals. This is clear evidence of the complexation between the cyclic aza-ether compound and halide anions. (C) 2000 The Electrochemical Society. S0013-4651 (99)04-037-9. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. USN, Res Lab, Washington, DC 20375 USA. RP Lee, HS (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 9 TC 13 Z9 14 U1 1 U2 7 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JAN PY 2000 VL 147 IS 1 BP 9 EP 14 DI 10.1149/1.1493856 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 275QZ UT WOS:000084832800002 ER PT J AU Bates, JB Dudney, NJ Neudecker, BJ Hart, FX Jun, HP Hackney, SA AF Bates, JB Dudney, NJ Neudecker, BJ Hart, FX Jun, HP Hackney, SA TI Preferred orientation of polycrystalline LiCoO2 films SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID LITHIUM BATTERIES; CATHODES; GROWTH AB Polycrystalline films of LiCoO2 deposited by radio frequency magnetron sputtering exhibited a strong preferred orientation or texturing after annealing at 700 degrees C. For films thicker than about 1 mu m, more than 90% of the grains were oriented with their (101) and (101) planes parallel to the substrate and less than 10% with their (003) planes parallel to the substrate. As the film thickness decreased below 1 mu m, the percentage of (003)-oriented grains increased until at a thickness of about 0.05 mu m, 100% of the grains were (003) oriented. These extremes in texturing were caused by the tendency to minimize volume strain energy for the thicker films or the surface energy for the very thin films. Films were deposited using different process gas mixtures and pressures, deposition rates, substrate temperatures: and substrate bias. Of these variables, only changes in substrate temperature could cause large changes in texturing of thick films from predominately (101)-(101) to (003). Although lithium ion diffusion should be much faster through cathodes with a high percentage of(101)- and (104)-oriented grains than through cathodes with predominately (003)-oriented grains, it was not possible to verify this expectation because the resistance of most cells was dominated by the electrolyte and electrolyte-cathode interface. Nonetheless, cells with cathodes thicker than about 2 mu m could deliver more than 50% of their maximum energies at discharge rates of 5 mA/cm(2) or higher. (C) 2000 The Electrochemical Society. S0013-4651(99)04-087-2. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ South, Dept Phys, Sewanee, TN 37383 USA. Michigan Technol Univ, Houghton, MI 49931 USA. RP Bates, JB (reprint author), Excellatron Corp, Smyrna, GA 30080 USA. RI Dudney, Nancy/I-6361-2016 OI Dudney, Nancy/0000-0001-7729-6178 NR 20 TC 237 Z9 248 U1 12 U2 138 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JAN PY 2000 VL 147 IS 1 BP 59 EP 70 DI 10.1149/1.1393157 PG 12 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 275QZ UT WOS:000084832800010 ER PT J AU Ren, X Springer, TE Gottesfeld, S AF Ren, X Springer, TE Gottesfeld, S TI Water and methanol uptakes in nafion membranes and membrane effects on direct methanol cell performance SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ELECTROLYTE FUEL-CELLS; OXYGEN REDUCTION; TRANSPORT AB This paper compares direct methanol fuel cells (DMFCs) employing two types of Nafion(R) (E.I. DuPont de Nemours and Company) membranes of different equivalent weight (EW). Methanol and water uptakes in 1100 and 1200 EW Nafion membranes were determined by weighing P2O5-dried and methanol solution-equilibrated membranes. Both methanol and water uptakes in the 1200 EW membrane were about 70-74% of those in the 1100 EW membrane. The methanol crossover rate corresponding to that in a DMFC at open circuit was measured using a voltammetric method in the DMFC configuration and under the same cell operating conditions. After accounting for the thickness difference between the membrane samples, the methanol crossover rate through a 1200 EW membrane was 52% of that through an 1100 EW membrane. To resolve the cathode and anode performances in an operating DMFC, a dynamic hydrogen electrode was used as a reference electrode. Results show that in an operating DMFC the cathode can be easily flooded. as shown in a DMFC using 1100 EW membrane. An increase in methanol crossover rare decreases the DMFC cathode potential at open circuit. At a high cell current density, the DMFC cathode potential can approach that of a H-2/air cull. (C) 2000 The Electrochemical Society. S0013-4651(99)05-093-4. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ren, X (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI ren, xiaoming/F-3953-2011 NR 21 TC 332 Z9 336 U1 3 U2 55 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JAN PY 2000 VL 147 IS 1 BP 92 EP 98 DI 10.1149/1.1393161 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 275QZ UT WOS:000084832800014 ER PT J AU Doyle, M Meyers, JP Newman, J AF Doyle, M Meyers, JP Newman, J TI Computer simulations of the impedance response of lithium rechargeable batteries SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID STATE-OF-CHARGE; NIOBIUM TRISELENIDE CATHODE; POROUS NICKEL ELECTRODES; AC-IMPEDANCE; ELECTROCHEMICAL IMPEDANCE; DIFFUSION-COEFFICIENT; CARBON ELECTRODES; ALKALINE MEDIA; INSERTION CELL; THIN-LAYER AB A mathematical model is developed to simulate the impedance response of a wide range of lithium rechargeable battery systems. The mathematical model is a macroscopic model of a full-cell sandwich utilizing porous electrode theory to treat the electrode region and concentrated solution theory for transport processes in solution. insertion processes are described with charge-transfer Kinetic expressions and solid-phase diffusion of lithium into the active electrode material. The impedance model assumes steady-state conditions and a linear response with the perturbation applied about the open-circuit condition for the battery. The simulated impedance response of a specific system, the lithium-polymer cell Li\PEO18LiCF3SO3\LiTiS2, is analyzed in more detail to illustrate several features of the impedance behavior. Particular attention is paid to the measurement of solid-phase lithium-ion diffusion coefficients in the insertion electrodes using impedance techniques. A number of complication that can lead to errors in diffusion-coefficient measurements based on impedance techniques are discussed. (C) 2000 The Electrochemical Society. S0013-4651(98)11-056-X. All rights reserved. C1 Dupont Co, Cent Res & Dev, Expt Stn, Wilmington, DE 19880 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Energy & Environm, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Doyle, M (reprint author), Dupont Co, Cent Res & Dev, Expt Stn, Wilmington, DE 19880 USA. RI Meyers, Jeremy/B-8814-2008; Newman, John/B-8650-2008 OI Newman, John/0000-0002-9267-4525 NR 67 TC 97 Z9 98 U1 3 U2 65 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JAN PY 2000 VL 147 IS 1 BP 99 EP 110 DI 10.1149/1.1393162 PG 12 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 275QZ UT WOS:000084832800015 ER PT J AU Buchheit, RG Martinez, MA Montes, LP AF Buchheit, RG Martinez, MA Montes, LP TI Evidence for Cu ion formation by dissolution and dealloying the Al2CuMg intermetallic compound in rotating ring-disk collection experiments SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID COPPER AB Rotating ring-disk collection experiments and stripping voltammetry have been used to detect Cu ions generated by dissolution of the Al2CuMg intermetallic compound in aqueous chloride solutions. Cu ions are generated under open-circuit conditions (open-circuit potential -0.930 V-SCE), or by slight anodic or cathodic polarization (+/- 0.050 V from the open-circuit potential). In all cases, Cu ion generation occurs even though the electrode potential is hundreds of millivolts negative of the equilibrium potential, Ec, Results show that Cu ion generation is strongly dependent on the degree of solution aeration, indicating a role fur Cu oxidants in the liberation process. Copper chloride-complex formation and local surface curvature effects can shift the Cu equilibrium potential in the active direction, but neither phenomenon appears to play a primary role in oxidation of Cu from the intermetallic compound. Rather, the results of this study support the notion that Cu ion generation involves (i) dealloying of the intermetallic compound, (ii) nonfaradaic liberation of mechanically and electrically isolated metallic Cu clusters by physical coarsening of the dealloyed particle, and (iii) oxidation of the electrically isolated Cu clusters. This Cu ion generation mechanism is believed to be a significant factor contributing to the poor corrosion resistance and poor conversion coating characteristics of Al2CuMg-bearing alloys. (C) 2000 The Electrochemical Society. S0013-4651(99)01-012-5. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Buchheit, RG (reprint author), Ohio State Univ, Dept Mat Sci & Engn, 116 W 19Th Ave, Columbus, OH 43210 USA. NR 12 TC 131 Z9 137 U1 2 U2 26 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JAN PY 2000 VL 147 IS 1 BP 119 EP 124 DI 10.1149/1.1393164 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 275QZ UT WOS:000084832800017 ER PT J AU Silling, SA AF Silling, SA TI Reformulation of elasticity theory for discontinuities and long-range forces SO JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS LA English DT Article DE dynamics; elastic material; fracture; stability and bifurcation; stress waves ID NONLOCAL ELASTICITY; SIMULATION; FRACTURE AB Some materials may naturally form discontinuities such as cracks as a result of deformation. As an aid to the modeling of such materials, a new framework for the basic equations of continuum mechanics, called the 'peridynamic' formulation, is proposed. The propagation of linear stress waves in the new theory is discussed, and wave dispersion relations are derived. Material stability and its connection with wave propagation is investigated, It is demonstrated by an example that the reformulated approach permits the solution of fracture problems using the same equations either on or off the crack surface or crack tip. This is an advantage for modeling problems in which the location of a crack is not known in advance. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Computat Phys & Mech Dept, Albuquerque, NM 87185 USA. RP Silling, SA (reprint author), Sandia Natl Labs, Computat Phys & Mech Dept, POB 5800, Albuquerque, NM 87185 USA. NR 15 TC 463 Z9 481 U1 20 U2 80 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-5096 J9 J MECH PHYS SOLIDS JI J. Mech. Phys. Solids PD JAN PY 2000 VL 48 IS 1 BP 175 EP 209 DI 10.1016/S0022-5096(99)00029-0 PG 35 WC Materials Science, Multidisciplinary; Mechanics; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 261YM UT WOS:000084038800007 ER PT J AU Tohyama, T Shibata, Y Maekawa, S Shen, ZX Nagaosa, N Miller, LL AF Tohyama, T Shibata, Y Maekawa, S Shen, ZX Nagaosa, N Miller, LL TI Spin liquid state around a doped hole in insulating cuprates SO JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN LA English DT Letter DE spin liquid; spin-charge separation; insulating cuprates; t-J model ID T-J MODEL; QUANTUM ANTIFERROMAGNET; SPECTRAL-FUNCTION; SUPERCONDUCTORS; PHOTOEMISSION; BI2SR2CACU2O8+DELTA; EXCITATIONS; PHASE AB The numerically exact diagonalization study on small clusters of the t-J model with second-and third-neighbor hopping terms shows that a novel spin liquid state is realized around a doped hole with momentum k=(pi, 0) and energy similar to 2J compared with that with (pi/2, pi/2) in insulating cuprates, where the spin and charge degrees of freedom are approximately decoupled. Our finding implies that the excitations in the insulating cuprates are mapped onto the d-wave resonating valence bond state. C1 Tohoku Univ, Inst Mat Res, Sendai, Miyagi 9808577, Japan. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Univ Tokyo, Dept Appl Phys, Bunkyo Ku, Tokyo 1138656, Japan. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Tohyama, T (reprint author), Tohoku Univ, Inst Mat Res, Sendai, Miyagi 9808577, Japan. RI Nagaosa, Naoto/G-7057-2012 NR 22 TC 29 Z9 29 U1 1 U2 3 PU PHYSICAL SOCIETY JAPAN PI TOKYO PA KIKAI-SHINKO BUILDING, 3-5-8 SHIBA-KOEN, MINATO-KU, TOKYO, 105, JAPAN SN 0031-9015 J9 J PHYS SOC JPN JI J. Phys. Soc. Jpn. PD JAN PY 2000 VL 69 IS 1 BP 9 EP 12 DI 10.1143/JPSJ.69.9 PG 4 WC Physics, Multidisciplinary SC Physics GA 295ZX UT WOS:000085999500003 ER PT J AU Kawabata, C Takeuchi, M Shenoy, SR Bishop, AR AF Kawabata, C Takeuchi, M Shenoy, SR Bishop, AR TI Critical temperature, critical current, and vortex loops in 3D anisotropic Josephson junction arrays SO JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN LA English DT Article DE 3D-XY/JJA model; Monte Carlo; vortex loop; critical temperature; critical current; quasi-universal clustering ID HIGH-TC SUPERCONDUCTORS; CURRENT-VOLTAGE CHARACTERISTICS; 3-DIMENSIONAL XY MODEL; HE-4 LAMBDA-TRANSITION; LAYERED SUPERCONDUCTORS; CRITICAL-BEHAVIOR; PHASE-TRANSITION; 2ND KIND; FLUCTUATIONS; VORTICES AB Monte Carlo simulations of a 3D anisotropic Josephson junction array are performed, to determine the critical temperature T-c(I, alpha) for the onset of phase incoherence. Here I is the external current drive at opposite surfaces, and alpha = E-J perpendicular to/E-J parallel to is the inter-/intra-layer Josephson coupling ratio. T-c(I, alpha) is equivalent to a critical current, I-c(T, alpha) fur the breakdown of global phase coherence. The temperature and anisotropy dependence of I-c(T, alpha) supports a physical picture of two vortex populations, quasi-2D and 3D in nature at small and large scales respectively, separated by a length scale r(perpendicular to) similar to 1/root alpha. C1 Okayama Univ, Fac Environm Sci & Technol, Okayama 7008530, Japan. Abdus Salam Int Ctr Theoret Phys, Condensed Matter Grp, I-34100 Trieste, Italy. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Kawabata, C (reprint author), Okayama Univ, Fac Environm Sci & Technol, 3-1-1 Tsushima Naka, Okayama 7008530, Japan. NR 64 TC 5 Z9 5 U1 0 U2 1 PU PHYSICAL SOCIETY JAPAN PI TOKYO PA KIKAI-SHINKO BUILDING, 3-5-8 SHIBA-KOEN, MINATO-KU, TOKYO, 105, JAPAN SN 0031-9015 J9 J PHYS SOC JPN JI J. Phys. Soc. Jpn. PD JAN PY 2000 VL 69 IS 1 BP 194 EP 202 DI 10.1143/JPSJ.69.194 PG 9 WC Physics, Multidisciplinary SC Physics GA 295ZX UT WOS:000085999500033 ER PT J AU Jensen, RP Preece, DS AF Jensen, RP Preece, DS TI Modelling explosive/rock interaction during presplitting, using ALE computational methods SO JOURNAL OF THE SOUTH AFRICAN INSTITUTE OF MINING AND METALLURGY LA English DT Article AB Arbitrary Lagrangian Eulerian (ALE) computational techniques allow treatment of gases, liquids and solids in the same simulation. ALE methods include the ability to treat shock waves in gases, liquids and solids and the interaction of shock waves with each other and with media from one of the other categories, ALE codes can also treat explosive detonation and the expansion of the explosive gases and their interaction with air and solids, ALEGRA is a 3-D ALE code that has been developed at Sandia National Laboratories over the past few years. ALEGRA has been applied to a 2-D simulation of presplitting using decoupled explosives in rock blasting with very interesting results. The detonation of the explosive at the bottom of the hole sends a shock wave up the borehole driven by the explosive gas expanding into air. The explosive gas compresses the air against the stemming column where it rebounds and recompresses at the bottom of the borehole. This type of ringing takes several cycles to damp out. The explosively induced expansion of the borehole is also treated by ALEGRA as well as the shock wave imparted to the rock. The presentation of this paper will include several computer animations to aid in understanding this complex phenomenon. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Jensen, RP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU SOUTH AFRICAN INST MIN METALL PI MARSHALLTOWN TRANSVAAL PA PO BOX 61127 11-13 MACLAREN ST 13TH FLOOR-CAPE TOWERS, MARSHALLTOWN TRANSVAAL 2107, SOUTH AFRICA SN 0038-223X J9 J S AFR I MIN METALL JI J. S. Afr. Inst. Min. Metall. PD JAN-FEB PY 2000 VL 100 IS 1 BP 23 EP 26 PG 4 WC Metallurgy & Metallurgical Engineering; Mining & Mineral Processing SC Metallurgy & Metallurgical Engineering; Mining & Mineral Processing GA 325EJ UT WOS:000087663100004 ER PT J AU Androsch, R Pyda, M Wang, H Wunderlich, B AF Androsch, R Pyda, M Wang, H Wunderlich, B TI A study of temperature-modulated differential scanning calorimetry with high-resolution infrared thermography SO JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY LA English DT Article DE differential scanning calorimetry (DSC); infrared thermography; phase angle; temperature gradient; temperature-modulated differential scanning calorimetry (TMDSC) ID DSC AB Temperature gradients within the sample and furnace in temperature-modulated differential scanning calorimetry (TMDSC) are studied for a power-compensation calorimeter of the Perkin Elmer type. The temperature measurements were made with a high-speed, high-resolution infrared camera. Differences between programmed and actual temperature amplitudes are determined as a function of sample thickness for a sawtooth modulation with up to 48 K min(-1) heating and cooling rates. Phase angles have been established, and the effect of open and sealed sample pans has been analyzed. A simple one-dimensional description of the observed effects is made and a three-dimensional one is suggested based on a model available in the literature. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RI Wang, Hsin/A-1942-2013 OI Wang, Hsin/0000-0003-2426-9867 NR 22 TC 15 Z9 16 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1418-2874 J9 J THERM ANAL CALORIM JI J. Therm. Anal. PY 2000 VL 61 IS 3 BP 661 EP 679 DI 10.1023/A:1010158621847 PG 19 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 366BZ UT WOS:000089986100001 ER PT J AU Burnham, AK AF Burnham, AK TI Application of the Sestak-Berggren equation to organic and inorganic materials of practical interest SO JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY LA English DT Article DE nucleation kinetics; Prout-Tompkins equation; sigmoidal kinetics; thermal decomposition kinetics ID KINETIC-PARAMETERS; PYROLYSIS; CELLULOSE; MICROPYROLYSIS; DISTRIBUTIONS; MODEL AB Reactions that have an initial acceleratory period are common in both organic and inorganic systems. The Sestak-Berggren equation, dx/dt= -kx(n)(1-x)(m)[-ln(x)](p), with p set to zero (also called the extended Prout-Tompkins (PT) equation) is an excellent empirical kinetic law for many of these systems. In this work, it is shown to fit both isothermal and constant heating rate pyrolysis data for a well-preserved algal kerogen in a petroleum source rock and two synthetic polymers (polycarbonate and poly-ether-etherketone), dehydration of calcium oxalate monohydrate, decomposition of ammonium percholorate, and diffusive release of gas implanted in materials. Activation energies derived by non-linear regression to multiple experiments are consistent with those derived by simple isoconversional methods. Errors caused by misapplication of first-order kinetics to single-heating-rate data are discussed briefly. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Burnham, AK (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 28 TC 54 Z9 54 U1 0 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1418-2874 J9 J THERM ANAL CALORIM JI J. Therm. Anal. PY 2000 VL 60 IS 3 BP 895 EP 908 DI 10.1023/A:1010163809501 PG 14 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 343JF UT WOS:000088698700019 ER PT J AU Wunderlich, B AF Wunderlich, B TI Teaching thermal analysis of polymeric materials SO JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY LA English DT Article DE computer aided teaching; materials; polymer AB Thermal analysis and polymers are two subjects in the field of chemistry and materials sciences that have not developed to the level commensurate with their importance. In this paper the reasons for this deficiency are traced to the history of the development of these subjects which led to only limited availability of courses of instruction. A first remedy to this problem is suggested, teaching via the internet. The attempt by the author to generate such a course is described in this paper. The course contains an up-to-date store of basic information. It is divided into 36 'lectures' and displayed in about 3000 computer screens filled with graphs, text, and hypertext. All lectures are downloadable. Including presentation software, each lecture requires only 1-3 Mbyte of computer memory. The inclusion of color, movies, and sound would exceed the capacity of most presently available personal computers, but might point the way to future of teaching the ever increasing number of subjects. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 6 TC 4 Z9 4 U1 1 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1418-2874 J9 J THERM ANAL CALORIM JI J. Therm. Anal. PY 2000 VL 59 IS 1-2 BP 7 EP 19 DI 10.1023/A:1010143523527 PG 13 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 286TU UT WOS:000085462800002 ER PT J AU Moon, I Androsch, R Chen, W Wunderlich, B AF Moon, I Androsch, R Chen, W Wunderlich, B TI The principles of micro-thermal analysis and its application to the study of macromolecules SO JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY LA English DT Article DE atomic force microscopy; microcalorimetry; polymers; temperature-modulation ID ATOMIC FORCE MICROSCOPE; CONDUCTIVITY; CALORIMETRY; PROBE AB A newly developed Micro-Thermal Analyzer affords images based on thermal properties such as thermal conductivity, thermal diffusivity, and permits localized thermal analyses on samples of a square micrometer area by combining the imaging ability of the atomic force microscope and the thermal characterization ability of temperature-modulated differential scanning calorimetry. Since thermal penetration depth depends on frequency, one can obtain depth profiles of thermal conductivity and thermal diffusivity by varying the modulation frequency. Also, the analyzer can be used to characterize phase-transition temperatures, such as glass and melting transitions, of small sample regions with a precision of about %3 K. Heating rates can be varied between 1 and 1500 K min(-1). Modulation frequencies can be applied in the range from 2 to 100 kHz. We applied this new type of instrument to characterize microscopic thermal and structural properties of various polymer systems. The operation principles of the instrument are described, application examples are presented, and the future of the technique is discussed. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 16 TC 32 Z9 32 U1 0 U2 5 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1418-2874 J9 J THERM ANAL CALORIM JI J. Therm. Anal. PY 2000 VL 59 IS 1-2 BP 187 EP 203 DI 10.1023/A:1010144230796 PG 17 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 286TU UT WOS:000085462800015 ER PT J AU Groenewold, GS Gresham, GL Gianotto, AK Avci, R AF Groenewold, GS Gresham, GL Gianotto, AK Avci, R TI Direct characterization of surface chemicals on hair samples using imaging SIMS SO JOURNAL OF TRACE AND MICROPROBE TECHNIQUES LA English DT Article DE SIMS; hair analysis; surface contaminants; conditioner; shampoo; surfactants; imaging ID ION MASS-SPECTROMETRY; SOIL PARTICLES; LEAF SURFACES; STATIC SIMS; ACIDS; EMISSION; SULFIDE AB Canine hair samples were analyzed as part of a program to assess the efficacy of imaging secondary ion mass spectrometry (SIMS) for the characterization of trace samples. The samples were analyzed as received, and subsequent to treatment with shampoo and/or conditioner products. Samples were mounted on silicon wafers using double sided tape, in such a manner that the tape did not contaminate the portion of the sample to be analyzed, nor was the tape exposed to the primary ion beam. The imaging SIMS instrument used enabled spectra to be generated only from the hair surface, in a manner which excluded contributions from the silicon mounting stage. The cation spectra of the untreated hair contained evidence for organic amines and polydimethylsiloxane (PDMS) contaminants, that originate from the canine's living environment. When the hair samples were treated with shampoo, the cation spectra showed that the amine-derived ions were removed, but the abundance of the PDMS-derived ions had increased. A series of PDMS-derived ions was also observed in the anion spectra, as was evidence for alkyl-, and ethoxylated alkyl-, sulfate species. Treatment of the hair samples with conditioner had a dramatic effect on the appearance of the cation spectra: higher mass alkylammonium species, present in the conditioner product, were measured with an intensity well above the detection limit. The identity of the alkylammonium species were confirmed by MS2 (mass spectrometry/mass spectrometry), using an ion trap SIMS instrument. When the hair samples were rinsed using water, the organic sulfates were removed, but the PDMS and the alkylammonium ions were not. Subsequent rinsing with hexane removed the PDMS, but did not remove the alkylammonium ions. The results indicate that several components of the hair care products are long lived on hair,and are readily detectable using SIMS. Characterization of surface chemicals may be useful for distinguishing between different samples. Copyright (C) 2000 by Marcel Dekker, Inc. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83401 USA. Montana State Univ, Image & Chem Anal Lab, Bozeman, MT 59717 USA. RP Groenewold, GS (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83401 USA. NR 33 TC 8 Z9 8 U1 1 U2 9 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0733-4680 J9 J TRACE MICROPROBE T JI J. Trace Microprobe Tech. PY 2000 VL 18 IS 1 BP 107 EP 119 PG 13 WC Chemistry, Analytical SC Chemistry GA 296WC UT WOS:000086048900010 ER PT J AU He, XM Baker, N Kehler, BA Walter, KC Nastasi, M Nakamura, Y AF He, XM Baker, N Kehler, BA Walter, KC Nastasi, M Nakamura, Y TI Structure, hardness, and tribological properties of reactive magnetron sputtered chromium nitride films SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID VACUUM-ARC EVAPORATION; COATINGS; DEPOSITION; STRESS; MICROSTRUCTURE; MECHANISMS AB Chromium nitride (CrN) films with Cr/N atomic ratios of 0.73-1.46 were prepared by reactive dc-magnetron sputtering with Ar as the sputtering gas and N-2 as the reactive gas. The application of a negative bias voltage to the substrates and the decrement of the gas flow ratio of N-2 to Ar (or F-N2/F-Ar) promoted the growth of CrN films with preferred orientations of (200) + (220), high Cr/N ratios, and high densities. The functional hardness and compressive stress were highly dependent on the magnitude of the bias voltage and the Cr/N ratio that was adjusted by the F-N2/F-Ar ratio during film deposition. The optimal energy conditions for ion impingement on growing CrN films with compact columnar crystal structure, high hardness, and enhanced tribological propel-ties were studied with respect to the modulations of the bias voltages and the Cr/N ratios. The CrN films with high hardness and high wear resistance were synthesized in this study at low bias voltages of -(100-300) V and F-N2/F-Ar ratios of 1-3. (C) 2000 American Vacuum Society. [S0734-2101(00)02701-9]. C1 Univ Calif Los Alamos Natl Lab, MST 8, Los Alamos, NM 87545 USA. Kagoshima Univ, Dept Engn Mech, Kagoshima 8900065, Japan. RP He, XM (reprint author), Univ Calif Los Alamos Natl Lab, MST 8, POB 1663, Los Alamos, NM 87545 USA. NR 27 TC 63 Z9 65 U1 4 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JAN-FEB PY 2000 VL 18 IS 1 BP 30 EP 36 DI 10.1116/1.582154 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 276CM UT WOS:000084858100005 ER PT J AU Erlebacher, J Aziz, MJ Chason, E Sinclair, MB Floro, JA AF Erlebacher, J Aziz, MJ Chason, E Sinclair, MB Floro, JA TI Nonlinear amplitude evolution during spontaneous patterning of ion-bombarded Si(001) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID MORPHOLOGICAL EQUILIBRATION; ROUGHENING INSTABILITY; VICINAL SURFACES; THIN-FILMS; SI; DIFFUSION AB The time evolution of the amplitude of periodic nanoscale ripple patterns formed on Ar+ sputtered Si(001) surfaces was examined using a recently developed in situ spectroscopic technique. At sufficiently long times, we find that the amplitude does not continue to grow exponentially as predicted by the standard Bradley-Harper sputter rippling model. In accounting for this discrepancy, we rule out effects related to the concentration of mobile species, high surface curvature, surface energy anisotropy, and ion-surface interactions. We observe that for all wavelengths the amplitude ceases to grow when the width of the topmost terrace of the ripples is reduced to approximately 25 nm. This observation suggests that a short circuit relaxation mechanism limits amplitude growth. A strategy for influencing the ultimate ripple amplitude is discussed. (C) 2000 American Vacuum Society. [S0734-2101(00)01001-0]. C1 Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Erlebacher, J (reprint author), Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RI Erlebacher, Jonah/A-3231-2010 NR 24 TC 95 Z9 96 U1 1 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JAN-FEB PY 2000 VL 18 IS 1 BP 115 EP 120 DI 10.1116/1.582127 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 276CM UT WOS:000084858100020 ER PT J AU Baer, DR Windisch, CF Engelhard, MH Danielson, MJ Jones, RH Vetrano, JS AF Baer, DR Windisch, CF Engelhard, MH Danielson, MJ Jones, RH Vetrano, JS TI Influence of Mg on the corrosion of Al SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID ROOM-TEMPERATURE; SEGREGATION; OXIDATION; SURFACE; ALLOYS AB This article summarizes a series of experiments to determine the influence of Mg on the corrosion and electrochemical behavior of Al. Magnesium is commonly added to increase the strength of lightweight nonheat treatable Al alloys. However, these alloys are susceptible to grain boundary dissolution, stress corrosion cracking, or hydrogen induced embrittlement due to changes in the alloy structure and elemental distribution during processing, welding, or in-service exposure to elevated temperatures. Auger electron spectroscopy and transmission electron microscopy measurements show that alloys having a distribution of Al3Mg2 (beta phase) precipitates and segregated Mg on grain boundaries are more susceptible to cracking. To understand the roles of Mg on the cracking process we compared the corrosion potential and film formation of pure Al, Al implanted with Mg, a 7 wt % Mg-Al alloy and pure Al3Mg2 phase; The surfaces of the specimens were cleaned and prepared in a surface analysis system and transferred in a vacuum transfer system to a corrosion cell. After solution exposure and electrochemical measurement the specimens were returned to the spectrometer and analyzed by x-ray photoelectron spectroscopy. The open circuit potentials for Al, Mg implanted Al, and the 7% alloy were nearly identical. However, the corrosion potential for the beta phase differs significantly. The thickness of the film formed on each of the samples is similar. Mg is observed to be depleted in the outer part of the oxide films, but somewhat enhanced near the oxide-metal interface. The results suggest that segregated Mg plays little role in the cracking and that hydrogen production at the beta phase particles may be the most significant factor. (C) 2000 American Vacuum Society. [S0734-2101 (00)01801-7]. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Baer, DR (reprint author), Pacific NW Natl Lab, MS K8-93, Richland, WA 99352 USA. RI Engelhard, Mark/F-1317-2010; Baer, Donald/J-6191-2013 OI Baer, Donald/0000-0003-0875-5961 NR 18 TC 39 Z9 39 U1 2 U2 14 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JAN-FEB PY 2000 VL 18 IS 1 BP 131 EP 136 DI 10.1116/1.582129 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 276CM UT WOS:000084858100022 ER PT J AU Maya, L AF Maya, L TI Plasma-assisted reduction of carbon dioxide in the gas phase SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID SHIFT REACTION AB The reduction of carbon dioxide by hydrogen, which constitutes the reverse water-gas shift reaction, is an active area of research because of its connection with the production of methanol and other fuels. Representative references are given,(1-3) that have been reported in the catalysis literature where most of this research is described. In contrast with this, studies dealing with the plasma-assisted reduction of carbon dioxide, as a subset of the subject, are rather limited. A variety of products such as diamond,(4) oxalic acid(5) or fuel species(6) have been obtained depending on the conditions. The present study was undertaken to explore the possibility of obtaining formic acid through the plasma-assisted reduction of carbon dioxide given the precedent that even a more complex molecule such as oxalic has been obtained.(5) The production of formic acid was not anticipated to take place cleanly given the mechanistic complexity of such a process. The study was conducted nevertheless to seek an alternative to an electrochemical pathway(7) to reduce carbon dioxide that has obvious shortcomings because of the requirement to dissolve the gas in a solvent, in addition to the limited concentration of reactant and products that might be obtained. Formic acid in the form of formate is a component of a cycle conceived to trap tritium from contaminated ground water(8) that uses carbon dioxide from a selective oxidation step and hydrogen/tritium from the electrochemical reduction of the contaminated water. The electrochemical oxidation of formate is catalyzed by means of terpyridine bipyridine oxo ruthenium (IV), a complex that shows remarkable isotope effects so that tritiated formate is selectively enriched and may be separated by ion exchange. [S0734-2101(00)04001-X]. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Maya, L (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 10 TC 6 Z9 6 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JAN-FEB PY 2000 VL 18 IS 1 BP 285 EP 287 DI 10.1116/1.582148 PG 3 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 276CM UT WOS:000084858100043 ER PT J AU Levinson, JA Shaqfeh, ESG Balooch, M Hamza, AV AF Levinson, JA Shaqfeh, ESG Balooch, M Hamza, AV TI Ion-assisted etching and profile development of silicon in molecular and atomic chlorine SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID GAS-SURFACE CHEMISTRY; CYCLOTRON-RESONANCE PLASMA; DYNAMICS SIMULATIONS; BEAM SCATTERING; CL-2 PLASMA; POLY-SI; CL2; SI(100); POLYSILICON; MECHANISMS AB An ion beam etching study, designed to characterize, the important kinetic and transport processes involved in the ion-assisted etching of silicon in both molecular and atomic chlorine, was performed. Monoenergetic argon ions were directed normal to a silicon wafer that was simultaneously exposed to a neutral molecular and/or atomic chlorine beam. Dissociation of the beam was induced by thermally heating the graphite tip of an effusive source via electron impact. Beam composition was characterized using a quadrupole mass spectrometer and was found to be in excellent agreement with a thermodynamic equilibrium. model at the source pressure and tip temperature. Unpatterned polysilicon wafers were etched to determine the ion-induced etching yields as a function of ion energy, ion to neutral flux ratio, and neutral flux composition. A physically based kinetic model was developed to represent the yield data, incorporating chlorine adsorption, atomic to molecular chlorine surface recombination, and the ion-induced desorption of adsorbed chlorine and silicon chloride products. Feature profile etching experiments using patterned silicon wafers were also performed under ion and neutral-limited conditions of varying neutral composition. Resulting profiles were examined for aspect ratio dependent etching effects, where traditional lag was observed for features etched using an isotropically distributed background chlorine flux and inverse lag was observed for features etched with a molecular and atomic chlorine Aux arriving directly from the effusive source. Microtrenching was also present in the etched features. Computer simulations of the etching process and profile development were performed using the kinetic model and a Line-of-sight re-emission model for the chlorine transport. The dependence of the yield on the ion angle of incidence was also incorporated into a simulation for an isotropically distributed molecular chlorine flux and was found to have a significant impact. on profile evolution as a function of the ion to neutral Bur ratio. Using the simulation,atomic to molecular chlorine recombination effects were also explored as a function of the surface recombination coefficient. Predictions of the simulations were compared to experimentally derived profiles and were found to be in good agreement. (C) 2000 American Vacuum Society. [S0734-211X(00)10301-4]. C1 Stanford Univ, Dept Chem Engn, Stanford, CA 94305 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Levinson, JA (reprint author), Stanford Univ, Dept Chem Engn, Stanford, CA 94305 USA. NR 52 TC 21 Z9 24 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JAN-FEB PY 2000 VL 18 IS 1 BP 172 EP 190 DI 10.1116/1.591170 PG 19 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 285DZ UT WOS:000085375600033 ER PT J AU Labun, AH Moffat, HK Cale, TS AF Labun, AH Moffat, HK Cale, TS TI Mechanistic feature-scale profile simulation of SiO2 low-pressure chemical vapor deposition by tetraethoxysilane pyrolysis SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID SILICON DIOXIDE; STEP COVERAGE; TETRAETHYLORTHOSILICATE; QUALITY; FILMS AB Simulation of chemical vapor deposition in submicron features typical of semiconductor devices has been facilitated by extending the EVOLVE [T. S. Gale, T. H. Gandy, and G. B. Raupp, J. Vac. Sci. Technol. A 9, 524 (1991)] thin film etch and deposition simulation code to use thermal reaction mechanisms expressed in the Chemkin format. This allows consistent coupling between EVOLVE and reactor simulation codes that use Chemkin. In an application of a reactor-scale simulation code providing surface fluxes to a feature-scale simulation code, a proposed reaction mechanism for tetraethoxysilane [Si(OC2H5)(4)] pyrolysis to deposit SiO2, which had been applied successfully to reactor-scale simulation, does not correctly predict the low step coverage over trenches observed under short reactor residence time conditions; One apparent discrepancy between the mechanism and profile-evolution observations is a reduced degree of sensitivity of the deposition rate to the presence of reaction products, i.e., the by-product inhibition effect is underpredicted. The cause of the Proposed mechanism's insensitivity to by-product inhibition is investigated with the combined reactor and topography simulators. This is done first by manipulating the surface-to-volume ratio of a simulated reactor and second by adjusting parameters in the proposed mechanism such as the calculated free energies of proposed surface species. The conclusion is that simply calibrating mechanism parameters to enhance the by-product inhibition can improve the fit to profile evolution data; however, the agreement between with reactor-scale data and simulations decreases. Additional surface reaction channels seem to be required to simultaneously reproduce experimental reactor-scale growth rates and feature-scale step coverages. (C) 2000 American Vacuum Society. [S0734-211X(00)09201-5]. C1 Compaq Comp Corp, Shrewsbury, MA 01545 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Rensselaer Polytech Inst, Dept Chem Engn, Sch Engn, Troy, NY 12180 USA. RP Labun, AH (reprint author), Compaq Comp Corp, 334 South St, Shrewsbury, MA 01545 USA. NR 18 TC 15 Z9 15 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JAN-FEB PY 2000 VL 18 IS 1 BP 267 EP 278 DI 10.1116/1.591182 PG 12 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 285DZ UT WOS:000085375600045 ER PT J AU Larson, DJ Russell, KF Cerezo, A AF Larson, DJ Russell, KF Cerezo, A TI Sharpening of field-ion specimens and positioning of features of interest by ion-beam milling SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID MICROSCOPY AB Atom-probe field-ion microscopy is a powerful technique used to study microstructural features such as precipitates and grain boundaries. However, the amount of material which can be analyzed in a field-ion specimen is usually limited by the blunting effects of field evaporation. This limitation can be overcome by the use of ion-beam milling to resharpen field-ion specimens blunted by evaporation. In addition, ion-beam milling allows the positioning of features of interest in the apex region of electropolished field-ion specimens, Ion milling has been found to proceed in two stages. Stage I is a radius-reduction stage during which there is only limited removal of material directly from the apex region, but the radius of curvature at the apex is reduced. Stage IT milling occurs after some sharpening of field-ion specimens has taken place and results in a more rapid translation of the specimen apex position with respect to features in the sample. The rate of material removal along the specimen axis direction depends on the specimen shank angle. (C) 2000 American Vacuum Society. [S0734-2101(00)02301-0]. C1 Oak Ridge Natl Lab, Microscopy & Microanalyt Sci Grp, Div Met & Ceram, Oak Ridge, TN 37831 USA. Univ Oxford, Dept Mat, Oxford OX1 3PH, England. RP Larson, DJ (reprint author), Seagate Technol, M-S NRW 102,7801 Comp Ave, Minneapolis, MN 55435 USA. NR 14 TC 9 Z9 9 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JAN-FEB PY 2000 VL 18 IS 1 BP 328 EP 333 DI 10.1116/1.591194 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 285DZ UT WOS:000085375600058 ER PT J AU Segalman, D Reese, G Field, R Fulcher, C AF Segalman, D Reese, G Field, R Fulcher, C TI Estimating the probability distribution of von Mises stress for structures undergoing random excitation SO JOURNAL OF VIBRATION AND ACOUSTICS-TRANSACTIONS OF THE ASME LA English DT Article AB The von Mises stress is often used as the metric for evaluating design margins, particularly for structures made of ductile materials. For deterministic loads, both static and dynamic, the calculation of von Mises stress is straightforward, as is the resulting calculation of reliability. For loads modeled as random processes, the task is different; the response to such loads is itself a random process and its properties must be determined in terms of those of both the loads and the system. This has been done in the past by Monte Carlo sampling of numerical realizations that reproduce the second order statistics of the problem. Here, we present a method that provides analytic expressions for the probability distributions of von Mises stress which can be evaluated efficiently and with good numerical precision. Further, this new approach has the important advantage of providing the asymptotic properties of the probability distribution. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Segalman, D (reprint author), Sandia Natl Labs, Org 9234,MS 0847,POB 5800, Albuquerque, NM 87185 USA. OI Field, Richard/0000-0002-2765-7032 NR 15 TC 10 Z9 13 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1048-9002 J9 J VIB ACOUST JI J. Vib. Acoust.-Trans. ASME PD JAN PY 2000 VL 122 IS 1 BP 42 EP 48 DI 10.1115/1.568442 PG 7 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 283BP UT WOS:000085256500008 ER PT J AU Pfister, T Jones, KW Wimmer, E AF Pfister, T Jones, KW Wimmer, E TI A cysteine-rich motif in poliovirus protein 2C(ATPase) is involved in RNA replication and binds zinc in vitro SO JOURNAL OF VIROLOGY LA English DT Article ID SITE-DIRECTED MUTAGENESIS; POLYMERASE CHAIN-REACTION; ESCHERICHIA-COLI; VIRAL-RNA; STRAND RNA; 2C PROTEIN; MEMBRANE PROLIFERATION; HELA-CELLS; VIRUS; COMPLEX AB Protein 2C(ATPase) of picornaviruses is involved in the rearrangement of host cell organelles, viral RNA replication, and encapsidation. However, the biochemical and molecular mechanisms by which 2C(ATPase) engages in these processes are not known. To characterize functional domains of 2C(ATPase) we have focused on a cysteine-rich motif near the carboxy terminus of poliovirus 2C(ATPase). This region, which is well conserved among enteroviruses and rhinoviruses displaying an amino acid arrangement resembling zinc finger motifs, was studied by genetic and biochemical analyses. A mutation that replaced the first cysteine residue of the motif with a serine was lethal. A mutant virus which, lacked the second of four potential coordination sites for zinc was temperature sensitive, At the restrictive temperature, RNA replication was inhibited,whereas translation and polyprotein processing, assayed in vitro and in vivo, appeared to be normal. An intragenomic second-site revertant which reinserted the missing coordination site for zinc and recovered RNA replication at the restrictive temperature was isolated. The cysteine-rich motif was sufficient to bind zinc in vitro, as assessed in the presence of 4-(2-pyridylazo)resorcinol by a colorimetric assay. Zinc binding, however, was not required for hydrolysis of ATP. 2C(ATPase) as web as its precursors 2BC and P2 were found to exist in a reduced form in poliovirus-infected cells. C1 SUNY Stony Brook, Dept Mol Genet & Microbiol, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Wimmer, E (reprint author), SUNY Stony Brook, Dept Mol Genet & Microbiol, Stony Brook, NY 11794 USA. FU NIAID NIH HHS [AI15122, AI32100, R01 AI015122, R01 AI032100, R37 AI015122] NR 66 TC 57 Z9 60 U1 1 U2 3 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0022-538X J9 J VIROL JI J. Virol. PD JAN PY 2000 VL 74 IS 1 BP 334 EP 343 PG 10 WC Virology SC Virology GA 263QQ UT WOS:000084137100039 PM 10590122 ER PT J AU Gaines, KF Lord, CG Boring, CS Brisbin, IL Gochfeld, M Burger, J AF Gaines, KF Lord, CG Boring, CS Brisbin, IL Gochfeld, M Burger, J TI Raccoons as potential vectors of radionuclide contamination to human food chains from a nuclear industrial site SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article DE contaminant transport; Procyon lotor; radiocesium; raccoon; risk assessment; Savannah River Sit; South Carolina ID COAL ASH; RADIOCESIUM; RESERVOIR; SEDIMENTS; PATTERNS; EFFLUENTS; COMMUNITY; VARIANCE; CS-137; EGGS AB Although the raccoon (Procyon lotor) is commonly harvested and consumed throughout the southeastern United States, little is known regarding the fate and effects of environmental pollutants to this species, and the potential for it to act as a contaminant vector to humans or other predators, Muscle and liver tissues were collected from 76 raccoons from locations on and near the Department of Energy's Savannah River Site (SRS) in South Carolina and analyzed for radiocesium (Cs-137). Raccoons were trapped from areas near a former reactor cooling reservoir known to be contaminated from former nuclear production activities, a stream drainage system also known to have received Cs-137 contamination from low level releases, and 4 on-site reference areas that have been unimpacted by nuclear production activities. Raccoons from 3 hunting areas 3-15 km of SRS were used as off-site reference samples. Cs-137 levels differed between the 3 treatment groups (contaminated, on-site reference, off-site reference) for both muscle and liver tissues. Muscle and liver samples from raccoons from on-site reference areas were higher in Cs-137 than those from off-site reference animals. Cs-137 in raccoon tissues from contaminated habitats exceeded levels in the pooled reference animals. The 2 contaminated areas differed in Cs-137 tissue levels. Only 1 of 20 raccoons from contaminated sites on the SRS exceeded the European Economic Community (EEC) limit for Cs-137 in edible muscle tissue of 0.6 Bq Cs-137/g fresh-weight edible muscle. Further, none of the raccoons from the on-site reference areas exceeded EEC Limits for muscle. It is unlikely that the hunting public faces any significant risk from exposure to raccoons from the SRS. Although some raccoons might stray off the SRS which is closed to public access, most of the heavily contaminated areas are not adjacent to the edges of the site, decreasing the potential for off-site movement of contaminated animals. C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. Rutgers State Univ, Nelson Biol Labs, Piscataway, NJ 08855 USA. Rutgers State Univ, Environm & Occupat Hlth Sci Inst, Piscataway, NJ 08855 USA. RP Gaines, KF (reprint author), Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. NR 62 TC 14 Z9 16 U1 1 U2 4 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 USA SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD JAN PY 2000 VL 64 IS 1 BP 199 EP 208 DI 10.2307/3802991 PG 10 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA 274VN UT WOS:000084785900023 ER PT J AU Bozell, JJ Hoberg, JO Dimmel, DR AF Bozell, JJ Hoberg, JO Dimmel, DR TI Heteropolyacid catalyzed oxidation of lignin and lignin models to benzoquinones SO JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY LA English DT Article ID NITROGEN-DIOXIDE OXIDATION; PHASE-TRANSFER CONDITIONS; TRANSITION-METAL CATALYSIS; DILUTE HYDROGEN-PEROXIDE; WATER-SOLUBLE SALTS; PULPING CATALYSTS; OLEFIN EPOXIDATION; ALLYLIC ALCOHOLS; BIPHASE MEDIUM; POM ANIONS AB Several metal catalysts were examined for their effectiveness in activating hydrogen peroxide and oxygen as oxidants for conversion of lignin models to benzoquinones. Good yields of quinones were observed when certain heteropolymetallates were used as catalysts in the presence of hydrogen peroxide. Oxygen was generally less effective. Oxidation of lignin samples gave 2-3 wt% yields of 2,6-dimethoxybenzoquinone. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Inst Paper Sci & Technol, Atlanta, GA 30318 USA. RP Bozell, JJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 63 TC 3 Z9 4 U1 1 U2 10 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0277-3813 J9 J WOOD CHEM TECHNOL JI J. Wood Chem. Technol. PY 2000 VL 20 IS 1 BP 19 EP 41 DI 10.1080/02773810009349622 PG 23 WC Materials Science, Paper & Wood SC Materials Science GA 285JW UT WOS:000085386800002 ER PT J AU Im, HG AF Im, HG TI Numerical studies of transient opposed-flow flames using adaptive time integration SO KSME INTERNATIONAL JOURNAL LA English DT Article DE unsteady flames; adaptive time integration AB Numerical simulations of unsteady opposed-flow flames are performed using an adaptive time integration method designed for differential-algebraic systems. The compressibility effect is considered in deriving the system of equations, such that the numerical difficulties associated with a high-index system are alleviated. The numerical method is implemented for systems with detailed chemical mechanisms and transport properties by utilizing the Chemkin software. Two test simulations are performeds hydrogen/air diffusion flames with an oscillatory strain rate and transient ignition of methane against heated air. Both results show that the rapid transient behavior is successfully captured by the numerical method. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Im, HG (reprint author), Sandia Natl Labs, Combust Res Facil, MS9051, Livermore, CA 94551 USA. RI Im, Hong/J-4317-2012 NR 14 TC 0 Z9 0 U1 0 U2 0 PU KOREAN SOC MECHANICAL ENGINEERS PI SEOUL PA KSTC NEW BLD. 7TH FLOOR, 635-4 YEOGSAM-DONG KANGNAM-KU, SEOUL 135-703, SOUTH KOREA SN 1226-4865 J9 KSME INT J JI KSME Int. J. PD JAN PY 2000 VL 14 IS 1 BP 103 EP 112 PG 10 WC Engineering, Mechanical SC Engineering GA 271ZL UT WOS:000084625500012 ER PT S AU Hall, LO Chawla, N Bowyer, KW Kegelmeyer, WP AF Hall, LO Chawla, N Bowyer, KW Kegelmeyer, WP BE Zaki, MJ Ho, CT TI Learning rules from distributed data SO LARGE-SCALE PARALLEL DATA MINING SE LECTURE NOTES IN ARTIFICIAL INTELLIGENCE LA English DT Article; Proceedings Paper CT Workshop on Large-Scale Parallel KDD Systems held in conjunction with the 5th International Conference on Knowledge Discovery and Data Mining CY AUG 05, 1999 CL SAN DIEGO, CALIFORNIA SP ACM, SIGKDD AB In this paper a concern about the accuracy (as a function of parallelism) of a certain class of distributed learning algorithms is raised, and one proposed improvement is illustrated. We focus on learning a single model from a set of disjoint data sets, which are distributed across a set of computers. The model is a set of rules. The distributed data sets may be disjoint for any of several reasons. In our approach, the first step is to construct a rule set (model) for each of the original disjoint data sets. Then rule sets are merged until an eventual final rule set is obtained which models the aggregate data. We show that this approach compares to directly creating a rule set from the aggregate data and promises faster learning. Accuracy can drop off as the degree of parallelism increases. However, an approach has been developed to extend the degree of parallelism achieved before this problem takes over. C1 Univ S Florida, Dept Comp Sci & Engn, Tampa, FL 33620 USA. Sandia Natl Labs, Adv Concepts Dept, Livermore, CA 94551 USA. RP Hall, LO (reprint author), Univ S Florida, Dept Comp Sci & Engn, ENB 118,4202 E Fowler Ave, Tampa, FL 33620 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-67194-3 J9 LECT NOTES ARTIF INT PY 2000 VL 1759 BP 211 EP 220 DI 10.1007/3-540-46502-2_11 PG 10 WC Computer Science, Artificial Intelligence SC Computer Science GA BS60W UT WOS:000170556000011 ER PT S AU Norton, DP Park, C Lee, YE Budai, JD Chisholm, MF Verebelyi, DT Christen, DK Kroeger, DM AF Norton, DP Park, C Lee, YE Budai, JD Chisholm, MF Verebelyi, DT Christen, DK Kroeger, DM BE Helvajian, H Sugioka, K Gower, MC Dubowski, JJ TI Pulsed-laser deposition of electronic oxides: superconductor and semiconductor applications SO LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Applications in Microelectronic and Optoelectronic Manufacturing V CY JAN 24-26, 2000 CL SAN JOSE, CA SP USAF Off Sci Res, SPIE DE pulsed-laser deposition; electronic oxides; superconductor; dielectric; dissimilar epitaxy; epitaxial growth ID CRITICAL-CURRENT DENSITY; MECHANICAL-PROPERTIES; BUFFER LAYERS; THIN-FILMS; GROWTH; SURFACES; SILICON; EVAPORATION; YBA2CU3O7; SYSTEM AB Over the past decade, pulsed-laser deposition (PLD) has proven to be one of the most versatile and effective methods for obtaining high-quality electronic oxide thin-film materials. Much of this success can be attributed to its initial use in depositing high temperature superconducting materials. However, pulsed-laser deposition is now a leading research tool in the development of various electronic oxide thin-film technologies. In this paper, recent progress in the deposition of oxide materials on dissimilar materials for both superconductor and semiconductor applications is discussed. Recent developments in the synthesis of superconducting wires via epitaxial growth of superconducting oxides on biaxially textured metal tapes is described. In addition, efforts to integrate high-k dielectric oxides on semiconductor surfaces using pulsed-laser deposition are highlighted. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Norton, DP (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 21 TC 0 Z9 0 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 0-8194-3550-3 J9 P SOC PHOTO-OPT INS PY 2000 VL 3933 BP 124 EP 130 DI 10.1117/12.387548 PG 7 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BQ53R UT WOS:000088674400013 ER PT S AU Demos, SG Sheehan, L Kozlowski, MR AF Demos, SG Sheehan, L Kozlowski, MR BE Helvajian, H Sugioka, K Gower, MC Dubowski, JJ TI Spectroscopic investigation of SiO2 surfaces of optical materials for high power lasers SO LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Applications in Microelectronic and Optoelectronic Manufacturing V CY JAN 24-26, 2000 CL SAN JOSE, CA SP USAF Off Sci Res, SPIE DE fused silica; surface quality; spectroscopy; Raman scattering ID INDUCED BREAKDOWN; SILICA; RAMAN; LUMINESCENCE; PRESSURE; GLASS AB High quality surfaces of fused silica optical materials were studied using microscopic fluorescence imaging as well as Raman and emission micro-spectroscopy. For as-polished surfaces optically active defect formations were detected on the surface of the material which vary in geometry, relative intensity and concentration depending on the polishing process. A partial correlation of these defects with subsequent laser damage sites was indicated. Following laser-induced damage the Raman and photoluminescence spectra indicated extensive material modification within the damage site. Emission spectra show at least three characteristic luminescence bands centered at 1.9 eV (650 nm), 2.2 eV (560 nm) and similar to 4.7 eV (similar to 440 nm). Raman scattering indicates that laser irradiation leads to compaction. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Demos, SG (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 17 TC 14 Z9 14 U1 1 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 0-8194-3550-3 J9 P SOC PHOTO-OPT INS PY 2000 VL 3933 BP 316 EP 320 DI 10.1117/12.387569 PG 5 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BQ53R UT WOS:000088674400033 ER PT S AU Romero, LA Dickey, FM AF Romero, LA Dickey, FM BE Dickey, FM Holswade, SC TI What makes a beam shaping problem difficult SO LASER BEAM SHAPING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Beam Shaping CY AUG 02-03, 2000 CL SAN DIEGO, CA SP SPIE AB We discuss what we believe are the three most important factors effecting the difficulty of a beam shaping problem: scaling, smoothness, and coherence. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Romero, LA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 1 Z9 2 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3740-9 J9 P SOC PHOTO-OPT INS PY 2000 VL 4095 BP 16 EP 25 DI 10.1117/12.405260 PG 10 WC Physics, Applied SC Physics GA BR61S UT WOS:000166959300002 ER PT S AU Setchell, RE AF Setchell, RE BE Dickey, FM Holswade, SC TI Laser injection optics for high-intensity transmission in multimode fibers SO LASER BEAM SHAPING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Beam Shaping CY AUG 02-03, 2000 CL SAN DIEGO, CA SP SPIE DE high-intensity fiber transmission; laser damage in optical fibers; beam-shaping optics ID DAMAGE; DELIVERY; SYSTEM; BEAM AB An increasing number of applications ate requiring fiber transmission of high-intensity laser pulses. Our particular interests have led us to examine carefully the fiber transmission of Q-switched pulses from multimode Nd:YAG lasers at their fundamental wavelength. The maximum pulse energy that can be transmitted through a particular fiber is limited by the onset of laser-induced breakdown and damage mechanisms. Laser breakdown at the fiber entrance face is often the first limiting process to be encountered, but other mechanisms can result in catastrophic damage at either fiber face, within the initial "entry" segment of the fiber, and at other internal sites along the fiber path. In the course of our studies we have examined a number of factors that govern the relative importance of different mechanisms, including laser characteristics, the design and alignment of injection optics, fiber end-face preparation, and fiber routing. The present study emphasizes the important criteria for injection optics in high-intensity fiber transmission, and illustrates the opportunities that now exist for innovative designs of optics to meet these criteria. Our consideration of diffractive optics to achieve desired injection criteria began in 1993, and we have evaluated a progression of designs since that time. In the present study, two recent designs for injection optics are compared by testing a sufficient number of fibers with each design to establish statistics for the onset of laser-induced breakdown and damage. In this testing we attempted to hold constant other factors that can influence damage statistics. Both designs performed well, although one was less successful in meeting all injection criteria and consequently showed a susceptibility to a particular damage process. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Setchell, RE (reprint author), Sandia Natl Labs, MS1421, Albuquerque, NM 87185 USA. NR 16 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 0-8194-3740-9 J9 P SOC PHOTO-OPT INS PY 2000 VL 4095 BP 74 EP 84 DI 10.1117/12.405250 PG 11 WC Physics, Applied SC Physics GA BR61S UT WOS:000166959300008 ER PT S AU Frank, AM Wilkins, PR Honig, J Moss, M Gillespie, C AF Frank, AM Wilkins, PR Honig, J Moss, M Gillespie, C BE Dickey, FM Holswade, SC TI High energy laser pulse multiplexing into a fused silica fiber array SO LASER BEAM SHAPING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Beam Shaping CY AUG 02-03, 2000 CL SAN DIEGO, CA SP SPIE AB A novel technique to multiplex high energy laser pulses from a Nd:YLF laser into an array of fibers at energies near the bulk damage limit of fused silica is presented with the object of delivering N equal high energy laser pulses with a minimal time dispersion. Characteristics of the multiple fiber system, diffractive grating splitter, and spatial mode structure of the laser to minimize fiber damage are presented along with preliminary results in scaling the system to larger fiber numbers (N similar to 200) with a high energy 10-Joule Nd:Glass laser system. Fiber array alignment techniques and morphologies of fiber damage will be also be presented and discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Frank, AM (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-281,Box 808, Livermore, CA 94550 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 0-8194-3740-9 J9 P SOC PHOTO-OPT INS PY 2000 VL 4095 BP 85 EP 97 DI 10.1117/12.405251 PG 13 WC Physics, Applied SC Physics GA BR61S UT WOS:000166959300009 ER PT S AU Honig, J AF Honig, J BE Dickey, FM Holswade, SC TI A 1-Joule laser for a 16-fiber injection system SO LASER BEAM SHAPING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Beam Shaping CY AUG 02-03, 2000 CL SAN DIEGO, CA SP SPIE DE Nd : YLF; fiber injection; multi-mode; fiber damage ID STIMULATED BRILLOUIN-SCATTERING; DESIGN; GLASS AB A 1-J laser was designed to launch light down 16, multi-mode fibers (400-mum-core dia.). A diffractive-optic splitter was designed in collaboration with Digital Optics Corporation(1) (DOC), and was delivered by DOG. Using this splitter, the energy injected into each fiber varied <1%. The spatial profile out of each fiber was such that there were no "hot spots," a flyer could successfully be launched and a PETN pellet could be initiated. Preliminary designs of the system were driven by system efficiency where a pristine TEM00 laser beam would be required. The laser is a master oscillator, power amplifier (MOPA) consisting of a 4-mm-dia. Nd:YLF rod in the stable, q-switched oscillator and a 9.5-mm-dia. Nd:YLF rod in the double-passed amplifier. Using a TEM00 oscillator beam resulted in excellent transmission efficiencies through the fibers at lower energies but proved to be quite unreliable at higher energies, causing premature fiber damage, flyer plate rupture, stimulated Raman scattering (SRS), and stimulated Brillouin scattering (SBS). Upon further investigation, it was found that both temporal and spatial beam formatting of the laser were required to successfully initiate the PETN. Results from the single-mode experiments, including fiber damage, SRS and SBS losses, will be presented. In addition, results showing the improvement that can be obtained by proper laser beam formatting will also be presented. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Honig, J (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-477,POB 808, Livermore, CA 94551 USA. NR 8 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 0-8194-3740-9 J9 P SOC PHOTO-OPT INS PY 2000 VL 4095 BP 98 EP 107 DI 10.1117/12.405252 PG 10 WC Physics, Applied SC Physics GA BR61S UT WOS:000166959300010 ER PT S AU Greenfield, SR Casson, JL Koskelo, AC AF Greenfield, SR Casson, JL Koskelo, AC BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Nanosecond interferometric studies of surface deformation induced by laser irradiation SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1999 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 31st Annual Boulder Damage Symposium on Laser-Induced Damage in Optical Materials CY OCT 04-07, 1999 CL BOULDER, CO SP Lawrence Livermore Natl Lab, Univ New Mexico, Ctr High Technol Mat, Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Def Evaluat & Res Agcy, NIST, Pacific NW Natl Lab, SPIE DE ablation; surface acoustic wave (SAW); Rayleigh wave; photoacoustics; laser ultrasonics; interferometry ID INDUCED DECOMPOSITION; ABLATION; DYNAMICS; FILM AB Transient surface morphology changes in dielectric materials induced by laser irradiation were investigated with time-resolved interferometry. Deformation images were acquired at various delay times after exposure to single pulses (100 ps at 1.064 mu m) on fresh sample regions. Above the ablation threshold, we observe prompt ejection of material and the formation of a single unipolar compressional surface acoustic wave propagating away from the ablation crater. For calcite, no deformation - either transient or permanent - is discernable at laser fluences below the threshold for material ejection. Below-threshold behavior was investigated using a phosphate glass sample with substantial near infrared absorption (Schott filter KG3), KG3 exhibits the formation of a small bulge roughly the size of the laser spot that reaches its maximum amplitude by similar to 5 ns. At lower laser fluences, diffusion of thermal energy away from that region causes a much weaker and broader bulge to appear on a slower time scale. At higher laser fluences, a pair of strong, unipolar rarefaction surface acoustic waves is launched, separating from the central region at roughly 17 and 22 ns. Details of the transient interferometry system will also be given. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Greenfield, SR (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 12 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 0-8194-3508-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 3902 BP 108 EP 117 DI 10.1117/12.379296 PG 10 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP86M UT WOS:000086446600013 ER PT S AU Kozlowski, MR Battersby, CL Demos, SG AF Kozlowski, MR Battersby, CL Demos, SG BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Luminescence investigation of SiO2 surfaces damaged by 0.35 mm laser illumination SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1999 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 31st Annual Boulder Damage Symposium on Laser-Induced Damage in Optical Materials CY OCT 04-07, 1999 CL BOULDER, CO SP Lawrence Livermore Natl Lab, Univ New Mexico, Ctr High Technol Mat, Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Def Evaluat & Res Agcy, NIST, Pacific NW Natl Lab, SPIE ID VISIBLE-LIGHT EMISSION; AMORPHOUS SIO2; PHOTOLUMINESCENCE; SILICA; GAMMA; FILMS AB Following initiation at absorbing surface flaws, UV laser-induced damage to polished fused-silica surfaces continues to grow upon subsequent illumination. In this study photoluminescence spectroscopy was used to detect the formation of a modified, absorbing layer of silica that could be responsible for the continued growth of the damage site. For damage sites created with pulsed 355 nm illumination, three characteristic photoluminescence peaks are detected within the damage sites when excited with a 351 nm CW beam. Two of the peaks are likely due to the well-known E' and NBOHC defects associated with oxygen vacancies and broken Si-O bonds, respectively. The third, and domimant, peak at 560 nm has not been clearly identified, but is likely associated with a change in stoichiometry of the silica. The relative intensities of the peaks are non-uniform across individual damage sites. The photoluminescence data is being combined with insights from various optical and electron microscopies to develop an understanding of laser-induced damage sites. The objective is to develop strategies to slow or stop the growth of the damage sites. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Kozlowski, MR (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 17 TC 19 Z9 19 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 0-8194-3508-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 3902 BP 138 EP 144 DI 10.1117/12.379338 PG 7 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP86M UT WOS:000086446600016 ER PT S AU Ferris, KF Exarhos, GJ Risser, SM AF Ferris, KF Exarhos, GJ Risser, SM BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Linear and nonlinear contributions on the dielectric response of zirconia and polyethylene films SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1999 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 31st Annual Boulder Damage Symposium on Laser-Induced Damage in Optical Materials CY OCT 04-07, 1999 CL BOULDER, CO SP Lawrence Livermore Natl Lab, Univ New Mexico, Ctr High Technol Mat, Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Def Evaluat & Res Agcy, NIST, Pacific NW Natl Lab, SPIE DE electric fields; dielectric response; nonlinear susceptibility; finite element AB Using the LOCALF method, we have examined electric field distributions for high (ZrO2,epsilon=12.5) and low (polyethylene,epsilon=2.26) dielectric susceptibility cases through systematic variations of defect concentration and orientation. The addition of nonlinear susceptibility terms to the conventional linear contributions in the dielectric formalism incrementally perturbs both the electric field intensities and predicted dielectric constants, having a greater influence on low dielectric materials. These effects are modulated by the relative ratios of the linear and nonlinear susceptibility terms for a material due to polarization-derived changes. Nonlinear effects can have a strong influence on the magnitude of these changes; potentially obscuring predicted changes in dielectric response due to microstructural detail. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Ferris, KF (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 13 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 0-8194-3508-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 3902 BP 274 EP 282 DI 10.1117/12.379330 PG 9 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP86M UT WOS:000086446600031 ER PT S AU Chow, R Berzins, LV Arnold, PA Erbert, GV AF Chow, R Berzins, LV Arnold, PA Erbert, GV BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Reversible laser damage of dichroic coatings in a high average power laser vacuum resonator SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1999 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 31st Annual Boulder Damage Symposium on Laser-Induced Damage in Optical Materials CY OCT 04-07, 1999 CL BOULDER, CO SP Lawrence Livermore Natl Lab, Univ New Mexico, Ctr High Technol Mat, Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Def Evaluat & Res Agcy, NIST, Pacific NW Natl Lab, SPIE DE vacuum; photochemistry; coating damage; dichroic coating; argon ion laser AB In our application, dichroics in a high average power, near-infrared, laser system have short operating lifetimes. These dichroics were used as the resonator fold mirrors and permited the transmission of the pumping argon (Ar) ion laser light. Representative samples of two different dichroic optics were taken off-line and the transmission performance monitored in various scenarios. Irradiating these optics under resonator vacuum conditions, (less than or equal to 1 mT, 11.7 kW/cm(2), Ar laser running all wavelengths) resulted in a degradation of transmission with time. Irradiating these optics in a rarefied oxygen atmosphere (1 to 10 T of oxygen, 11.7 kW/cm(2) Ar laser running all wavelengths) the transmission remained steady over a period of days. The transmission loss observed in the optic tested in vacuum was somewhat reversible if the optic was subsequently irradiated in a rarefied oxygen atmosphere. This reversibility was only possible if the transmission degradation was not too severe. Further tests demonstrated that an atmosphere of 10 T of air also prevented the transmission degradation. In addition, tests were performed to demonstrate that the optic damage was not caused by the ultra-violet component in the Ar ion laser. Mechanisms that may account for this behavior are proposed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Chow, R (reprint author), Univ Calif Lawrence Livermore Natl Lab, Mail Stop 7000 East Ave,L-463, Livermore, CA 94551 USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3508-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 3902 BP 283 EP 291 DI 10.1117/12.379346 PG 9 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP86M UT WOS:000086446600032 ER PT S AU Shinn, M Benson, S Biallas, G Bohn, CL Douglas, D Dylla, F Evans, R Fugitt, J Gubeli, J Hill, R Jordan, K Krafft, G Li, R Merminga, L Neil, GR Oepts, D Piot, P Preble, J Siggins, T Walker, R Yunn, B AF Shinn, M Benson, S Biallas, G Bohn, CL Douglas, D Dylla, F Evans, R Fugitt, J Gubeli, J Hill, R Jordan, K Krafft, G Li, R Merminga, L Neil, GR Oepts, D Piot, P Preble, J Siggins, T Walker, R Yunn, B BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI The Jefferson Lab FEL user facility SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1999 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 31st Annual Boulder Damage Symposium on Laser-Induced Damage in Optical Materials CY OCT 04-07, 1999 CL BOULDER, CO SP Lawrence Livermore Natl Lab, Univ New Mexico, Ctr High Technol Mat, Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Def Evaluat & Res Agcy, NIST, Pacific NW Natl Lab, SPIE DE free-electron laser; high average power laser; ultrafast laser; materials processing; laser applications AB Jefferson Lab's IR Demo FEL Facility includes an associated 600 m(2) user facility containing six separate laboratory areas. In the summer of 1999 we began delivery of beam into two of these labs as part of our commissioning of the FEL optical transport and laser safety systems. The high average power capability (kilowatt-level) in the mid-infrared (3-6.6 microns), along with an ultrafast(similar to 1 ps) high PRF (10's MHz) temporal structure makes this laser a unique source for both applied and basic research. While commissioning, we conducted several tests, primarily of laser-materials interactions that take advantage of the unique characteristics of this FEL. An overview of the FEL facility and its current performance, along with a synopsis of current and future experiments, will be presented. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Shinn, M (reprint author), Thomas Jefferson Natl Accelerator Facil, 12000 Jefferson Ave, Newport News, VA 23606 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 0-8194-3508-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 3902 BP 355 EP 360 DI 10.1117/12.379347 PG 6 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP86M UT WOS:000086446600040 ER PT S AU Sharp, R Runkel, M AF Sharp, R Runkel, M BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Automated damage onset analysis techniques applied to KDP damage and the Zeus small area damage test facility SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1999 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 31st Annual Boulder Damage Symposium on Laser-Induced Damage in Optical Materials CY OCT 04-07, 1999 CL BOULDER, CO SP Lawrence Livermore Natl Lab, Univ New Mexico, Ctr High Technol Mat, Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Def Evaluat & Res Agcy, NIST, Pacific NW Natl Lab, SPIE DE KDP; bulk damage; automated onset; signal processing; damage detection AB Automated damage testing of KDP using LLNL's Zeus automated damage test system(1) has allowed the statistics of KDP bulk damage to be investigated. Samples are now characterized by the cumulative damage probability curve, or S-curve, that is generated from hundreds of individual test sites per sample. A HeNe laser/PMT scatter diagnostic is used to determine the onset of damage at each test site. The nature of KDP bulk damage is such that each scatter signal may possess many different indicators of a damage event. Because of this, the determination of the initial onset for each scatter trace is not a straightforward affair and has required considerable manual analysis. The amount of testing required by crystal development for the National Ignition Facility (MF) has made it impractical to continue analysis by hand. Because of this, we have developed and implemented algorithms for analyzing the scatter traces by computer. We discuss the signal cleaning algorithms and damage determination criteria that have lead to the successful implementation of a LabView based analysis code. For the typical R/1 damage data set, the program can find the correct damage onset in more than 80% of the cases, with the remaining 20% being left to operator determination. The potential time savings for data analysis is on the order of similar to 100X over manual analysis and is expected to result in the savings of at least 400 man-hours over the next 3 years of NIF quality assurance testing. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Sharp, R (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 4 TC 9 Z9 10 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 0-8194-3508-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 3902 BP 361 EP 368 DI 10.1117/12.379305 PG 8 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP86M UT WOS:000086446600041 ER PT S AU Demos, SG Radousky, HB Staggs, M Runkel, M Burnham, A AF Demos, SG Radousky, HB Staggs, M Runkel, M Burnham, A BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Laser induced material modification in the bulk KDP crystals SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1999 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 31st Annual Boulder Damage Symposium on Laser-Induced Damage in Optical Materials CY OCT 04-07, 1999 CL BOULDER, CO SP Lawrence Livermore Natl Lab, Univ New Mexico, Ctr High Technol Mat, Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Def Evaluat & Res Agcy, NIST, Pacific NW Natl Lab, SPIE DE damage; KDP; material modification; spectroscopy AB Laser induced material modifications in the bulk and on the surface of KDP (kh(2)PO(4)) and DKDDP (70-80% deuterated KDP) are studied using fluorescence imaging and spectroscopy. Photoluminescence is observed at damaged regions following above threshold exposure with an emission peak centered at 550-nm In addition, surfaces exposed to >100 high power, 355-nm laser pulses reveal a reduced surface finishing quality as evidenced by an associated emission under UV photoexcitation. The emission spectra from the laser-induced damage sites and the laser degraded surfaces are similar suggesting the generation of similar defect species. 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 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 0-8194-3508-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 3902 BP 428 EP 435 DI 10.1117/12.379326 PG 8 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP86M UT WOS:000086446600048 ER PT S AU Runkel, M Sharp, R AF Runkel, M Sharp, R BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Modeling KDP bulk damage curves for prediction of large-area damage performance SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1999 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 31st Annual Boulder Damage Symposium on Laser-Induced Damage in Optical Materials CY OCT 04-07, 1999 CL BOULDER, CO SP Lawrence Livermore Natl Lab, Univ New Mexico, Ctr High Technol Mat, Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Def Evaluat & Res Agcy, NIST, Pacific NW Natl Lab, SPIE DE KDP; bulk damage; damage statistics; exponential evolution; curve fitting ID SURFACE; ONSET AB Over the past two years extensive experimentation has been carried out to determine the nature of bulk damage in KDP. Automated damage testing with small beams has made it possible to rapidly investigate damage statistics and its connection to growth parameter variation. Over this time we have built up an encyclopedia of many damage curves but only relatively few samples have been tested with large beams. The scarcity of data makes it difficult to estimate how future crystals will perform on the NIF, and the campaign nature of large beam testing is not suitable for efficient testing of many samples with rapid turn-around. It is therefore desirable to have analytical tools in place that could make reliable predictions of large-beam performance based on small-beam damage probability measurements. To that end, we discuss the application of exponential and power law damage evolution within the framework of Poisson statistics in this memo. We describe the results of fitting these models to various damage probability curves on KDP including the heavily investigated KDP214 samples. We find that both models are capable of fitting the damage probability S-curves quite well but there are multiple parameter sets for each model that produce comparable chi(2) values. In addition, the fit parameters from the exponential model do not agree well with the measured evolution from large-beam OSL experiments where pinpoint density was shown to evolve according to n(F)=n(0)exp(bF). The largest discrepancy is in determination of the b values. For the O'Connell formalism of the power law case developed here, we find that the best-fit powers have approximately the same magnitude as the Weibull exponent of Felt's formalism, but it is difficult to extract information about the defect concentration using the O'Connell approach. In addition, we found that the power law case provides slightly better chi(2) values in roughly half of the cases. We discuss these results in terms of fluence measurement precision and the observed fluctuation of damage density observed on OSL testing. We conclude that these two formalisms are not yet well-enough developed to provide reliable parameters for predicting large-scale damage performance of KDP. In outlining possible steps for refining the models, we also call for any future small-spot damage model to include the effects of laser conditioning. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Runkel, M (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-250,7000 East Ave, Livermore, CA 94550 USA. NR 17 TC 2 Z9 2 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3508-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 3902 BP 436 EP 448 DI 10.1117/12.379315 PG 13 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP86M UT WOS:000086446600049 ER PT S AU Wheeler, EK McWhirter, JT Whitman, PK Thorsness, C De Yoreo, J Thomas, TM Hester, M AF Wheeler, EK McWhirter, JT Whitman, PK Thorsness, C De Yoreo, J Thomas, TM Hester, M BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI Scatter loss from environmental degradation of KDP crystals SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1999 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 31st Annual Boulder Damage Symposium on Laser-Induced Damage in Optical Materials CY OCT 04-07, 1999 CL BOULDER, CO SP Lawrence Livermore Natl Lab, Univ New Mexico, Ctr High Technol Mat, Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Def Evaluat & Res Agcy, NIST, Pacific NW Natl Lab, SPIE AB Severe scattering losses from KDP crystals have been correlated with the exposure of porous sol AR coated crystals to ambient humidity. The scattering is attributed to formation of etch pits which develop under the coating on the KDP surface along crystallographic axes. This high angle scattering can in turn produce laser damage of downstream optics either through modulation of the beam or by optic contamination from ablation of adjacent metal structures. We have developed a simple tool to characterize the evolution of scatter from sol-coated KDP surfaces. We have measured the rate of etch pit formation as a function of relative humidity and surface treatment using both microscopy and scattering. We will discuss various surface treatments which can be utilized to retard or eliminate the environmental degradation of KDP crystals. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wheeler, EK (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 2 TC 4 Z9 4 U1 3 U2 7 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3508-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 3902 BP 451 EP 459 DI 10.1117/12.379328 PG 9 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP86M UT WOS:000086446600051 ER PT S AU Qian, SN Takacs, P AF Qian, SN Takacs, P BE Kujawinska, M Pryputniewicz, RJ Takeda, M Brown, GM Juptner, WPO TI Precise angle monitor based on the concept of pencil-beam interferometry SO LASER INTERFEROMETRY X: TECHNIQUES AND ANALYSIS AND APPLICATIONS, PTS A AND B SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Interferometry X CY JUL 31-AUG 01, 2000 CL SAN DIEGO, CA SP SPIE DE angle measurement; pencil-beam interferometry; precise; LTP; autocollimator ID LONG-TRACE-PROFILER; HEAT-LOAD MIRROR; DISTORTION PROFILE; LTP AB The precise angle monitoring is a very important metrology task for research, development and industrials applications. Autocollimator is one of the most powerful and widely applied instruments for small angle monitoring, which is based on the principle of geometric optics, in this paper we introduce a new precise angle monitoring system, Pencil-beam Angle Monitor (PAM), base on pencil beam interferometry. It's principle of operation is a combination of physical and geometrical optics. The angle calculation method is similar to the autocollimator. However, the autocollimator creates a cross image but the precise pencil-beam angle monitoring system produces an interference fringe on the focal plane. The advantages of the PAM are: high angular sensitivity, long-term stability character making angle monitoring over long time periods possible, high measurement accuracy in the order of sub-microradian, simultaneous measurement ability in two perpendicular directions or on two different objects, dynamic measurement possibility, insensitive to the vibration and air turbulence, automatic display, storage and analysis by use of the computer, small beam diameter making the alignment extremely easy and longer test distance. Some test examples are presented. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Qian, SN (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 12 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 0-8194-3746-8 J9 P SOC PHOTO-OPT INS PY 2000 VL 4101 BP 263 EP 272 PN A&B PG 10 WC Optics SC Optics GA BR57X UT WOS:000166853400030 ER PT S AU Geohegan, DB Puretzky, AA Fan, XD Guillorn, MA Simpson, ML Merkulov, VI Pennycook, SJ AF Geohegan, DB Puretzky, AA Fan, XD Guillorn, MA Simpson, ML Merkulov, VI Pennycook, SJ BE Haglund, RF Wood, RF TI In situ plasma diagnostic investigations of single-wall carbon nanotube synthesis by laser ablation of C-Ni-Co targets SO LASER PLASMA GENERATION AND DIAGNOSTICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Plasma Generation and Diagnostics CY JAN 27, 2000 CL SAN JOSE, CA SP SPIE DE carbon nanotubes; laser plasmas; spectroscopy; in situ diagnostics; nanoparticles; hydrodynamics ID LARGE-SCALE; KRF-LASER; BACKGROUND GASES; DYNAMICS; PLUME; SPECTROSCOPY; VAPORIZATION; PYROLYSIS; CHEMISTRY; GRAPHITE AB Single-wall carbon nanotubes are formed by Nd:YAG laser vaporization of a graphite/(1 at. % Ni, I at. % Co) target into flowing argon (500 Torr) within a quartz tube furnace (1000 degrees C). Here, this process is investigated for the first time with time-resolved laser-induced luminescence imaging and spectroscopy of Co atoms, C-2 and C-3 molecules, and clusters. These measurements under actual synthesis conditions show that the plume of vaporized material is segregated and confined within a vortex ring which maintains a similar to 1 cm(3) volume for several seconds. Using time-resolved spectroscopy and spectroscopic imaging, the time for conversion of atomic and molecular species to clusters was measured for both carbon (200 mu s) and cobalt (2 ms). This rapid conversion of carbon to nanoparticles, combined with transmission electron microscopy analysis of the collected deposits, indicate that nanotube growth occurs during several seconds of time from a feedstock of mixed nanoparticles in the gas-suspended plume. By adjusting the time spent by the plume within the high-temperature zone using these in situ diagnostics, single-walled nanotubes of controlled length were grown at an estimated rate of 0.2 mu m/s. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Geohegan, DB (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Simpson, Michael/A-8410-2011; Puretzky, Alexander/B-5567-2016; Geohegan, David/D-3599-2013 OI Simpson, Michael/0000-0002-3933-3457; Puretzky, Alexander/0000-0002-9996-4429; Geohegan, David/0000-0003-0273-3139 NR 37 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 0-8194-3552-X J9 P SOC PHOTO-OPT INS PY 2000 VL 3935 BP 2 EP 13 DI 10.1117/12.380791 PG 12 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP95F UT WOS:000086713900001 ER PT S AU Wood, RF Leboeuf, JN Geohegan, DB Puretzky, AA Chen, KR AF Wood, RF Leboeuf, JN Geohegan, DB Puretzky, AA Chen, KR BE Haglund, RF Wood, RF TI Aspects of nanoparticle formation during pulsed laser ablation SO LASER PLASMA GENERATION AND DIAGNOSTICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Plasma Generation and Diagnostics CY JAN 27, 2000 CL SAN JOSE, CA SP SPIE DE nanoparticles; laser ablation; computer modeling; nucleation theory ID INERT-GAS; DEPOSITION; DYNAMICS AB Laser ablation is one of the most effective ways of making single-wall carbon nanotubes. Although the process is poorly understood, the importance of nanoparticle formation to initiate tube growth is evident. While some groups have concluded that nanoparticles can form in vacuum, we have argued that this is unlikely because the expansion of the plume is so rapid that the "freezing limit" is reached too rapidly for nucleation and growth to the observed size. A background gas changes the dynamics completely. Calculations show that in a few microseconds the ablated plume is dramatically slowed by the "snowplowing" of the background gas into a peak whose density is much greater than its initial density. The ablated material is trapped within this peak. The question then arises as to how this peak dissipates by diffusion. A simple calculation shows that it is at this point that a drastic change in the timescale of the process occurs so that there is ample time (milliseconds) for nanoparticles to nucleate and grow. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Wood, RF (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Puretzky, Alexander/B-5567-2016; Geohegan, David/D-3599-2013 OI Puretzky, Alexander/0000-0002-9996-4429; Geohegan, David/0000-0003-0273-3139 NR 18 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 0-8194-3552-X J9 P SOC PHOTO-OPT INS PY 2000 VL 3935 BP 57 EP 65 DI 10.1117/12.380807 PG 9 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP95F UT WOS:000086713900007 ER PT S AU Komashko, AM Feit, MD Rubenchik, AM AF Komashko, AM Feit, MD Rubenchik, AM BE Haglund, RF Wood, RF TI Modeling of long term behavior of ablation plumes produced with ultrashort laser pulses SO LASER PLASMA GENERATION AND DIAGNOSTICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Plasma Generation and Diagnostics CY JAN 27, 2000 CL SAN JOSE, CA SP SPIE DE simulation; ultrashort laser pulses; ablation; expansion; ellipsoid model; plume directionality AB Expansion of ablation plumes created by intense ultrashort lasers is determined by various complicated physical processes which have very different spatial and time scales. Since complete simulation by one model is practically impossible, we suggest using two models describing initial and final stages that can be matched at an intermediate time. The proposed modeling procedure connects laser parameters to plume properties far away from the ablation spot. Laser material interaction and beginning of the expansion are simulated with a one-dimensional hydrodynamics code and the final stage is modeled using an analytical solution for an expanding three-dimensional ellipsoidal gas cloud. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Komashko, AM (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,Mail Stop L-438, Livermore, CA 94550 USA. RI Feit, Michael/A-4480-2009 NR 11 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 0-8194-3552-X J9 P SOC PHOTO-OPT INS PY 2000 VL 3935 BP 97 EP 103 DI 10.1117/12.380796 PG 7 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP95F UT WOS:000086713900011 ER PT S AU Smithpeter, CL Nellums, RO Lebien, SM Studor, G AF Smithpeter, CL Nellums, RO Lebien, SM Studor, G BE Kamerman, GW Singh, UN Werner, C Molebny, VV TI A miniature, high-resolution laser radar operating at video rates SO LASER RADAR TECHNOLOGY AND APPLICATIONS V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Radar Technology and Applications V CY APR 26-28, 2000 CL ORLANDO, FL SP SPIE DE range; imaging; laser; time of flight; heterodyne; phase; modulation; miniature; fine resolution AB We are developing a laser radar to meet the needs of NASA for a 5-lb, 150 in(3) image sensor with a pixel range accuracy of 0.1-inch. NASA applications include structural dynamics measurements, navigation guidance in rendezvous and proximity operations, and space vehicle inspection. The sensor is based on the scannerless range imager architecture developed at Sandia. This architecture modulates laser floodlight illumination and a focal plane receiver to phase encode the laser time of flight (TOF) for each pixel. We believe this approach has significant advantages over architectures directly measuring TOF including high data rate, reduced detector bandwidth, and conventional focal plane array (FPA) detection. A limitation of the phase detection technique is its periodic nature, which provides relative range information over a finite ambiguity interval. To extend the operating interval while maintaining a given range resolution, a LADAR sensor using dual modulation frequencies has been developed. The modulation frequency values can be scaled to meet the resolution and range interval requirements of different applications. Results from the miniature NASA sensor illustrate the advantages of the dual-frequency operation and the ability to provide the range images of 640 by 480 pixels at 30 frames per second. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Smithpeter, CL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 9 TC 15 Z9 15 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 0-8194-3661-5 J9 P SOC PHOTO-OPT INS PY 2000 VL 4035 BP 279 EP 286 DI 10.1117/12.397801 PG 8 WC Remote Sensing; Optics; Physics, Applied SC Remote Sensing; Optics; Physics GA BR61N UT WOS:000166958000027 ER PT B AU Miles, P AF Miles, P BE Adrian, RJ Durao, DFG Durst, F Heitor, MV Maeda, M Whitelaw, JH TI In-cylinder measurements of mixture composition for investigation of residual gas scavenging SO LASER TECHNIQUES APPLIED TO FLUID MECHANICS LA English DT Proceedings Paper CT 9th International Symposium on Applications of Laser Techniques to Fluid Mechanics CY JUL 13-16, 1998 CL CALOUSTE GULBENKIAN FDN, LISBON, PORTUGAL SP European Res Off, USA, USN, USAF, Lusoamer Fdn Dev, Calouste Gulbenkian Fdn, Portuguese Sci & Technol Fdn, Inst Superior Tecn HO CALOUSTE GULBENKIAN FDN DE Raman scattering; residual gas scavenging AB Laser Raman scattering with broadband signal detection is employed to simultaneously measure the mole fractions of CO2, O-2, N-2, C3H8, and H2O under conditions simulating a cold start. The engine is operated with well-premixed fuel and air, such that each of the measured species can be used to independently estimate the mole fraction of burnt residual gases. The residual gas mole fraction estimates are subsequently examined for consistency and for evidence of poor scavenging of H2O due to condensation on the cold combustion chamber walls. The data indicate that if this mechanism inhibiting H2O scavenging is operative, it results in H2O number densities which are only 10-15% higher than expected. It is suggested that these higher than expected levels of H2O may be associated with Raman scattered light from condensate films on the windows. Raman scattering techniques using backscatter collection geometries are expected to be more sensitive to light scattered from condensate films, which may explain previously measured high H2O mole fractions. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. RP Miles, P (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-66738-5 PY 2000 BP 457 EP 471 PG 15 WC Engineering, Mechanical; Instruments & Instrumentation; Mechanics; Optics; Physics, Fluids & Plasmas SC Engineering; Instruments & Instrumentation; Mechanics; Optics; Physics GA BQ09R UT WOS:000087171900030 ER PT S AU Kim, BM Feit, MD Rubenchik, AM Komashko, AM Reidt, S Eichler, J Da Silva, LB AF Kim, BM Feit, MD Rubenchik, AM Komashko, AM Reidt, S Eichler, J Da Silva, LB BE Duncan, DD Hollinger, JO Jacques, SL TI Analysis of stress waves generated in water using ultrashort laser pulses SO LASER-TISSUE INTERACTION XI: PHOTOCHEMICAL, PHOTOTHERMAL, AND PHOTOMECHANICAL SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Laser-Tissue Interaction XI - Photochemical, Photothermal, and Photomechanical CY JAN 22-27, 2000 CL SAN JOSE, CA SP USAF Off Sci Res, SPIE, Int Biomed Opt Soc ID FEMTOSECOND AB A Mach-Zehnder interferometer was used for analysis of pressure waves generated by ultrashort laser pulse ablation of water. It was found that the shock wave generated by plasma formation rapidly decays to an acoustic wave. Both experimental and theoretical studies demonstrated that the energy transfer to the mechanical shock was less than 1%. C1 Lawrence Livermore Natl Lab, Med Technol Program, Livermore, CA 94550 USA. RP Kim, BM (reprint author), Lawrence Livermore Natl Lab, Med Technol Program, Livermore, CA 94550 USA. RI Feit, Michael/A-4480-2009 NR 3 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 0-8194-3530-9 J9 PROC SPIE PY 2000 VL 3914 BP 177 EP 182 DI 10.1117/12.388043 PG 6 WC Engineering, Biomedical; Optics SC Engineering; Optics GA BQ53Q UT WOS:000088674300021 ER PT S AU Visuri, SR Heredia, N AF Visuri, SR Heredia, N BE Duncan, DD Hollinger, JO Jacques, SL TI Opto-acoustic cell permeation SO LASER-TISSUE INTERACTION XI: PHOTOCHEMICAL, PHOTOTHERMAL, AND PHOTOMECHANICAL SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Laser-Tissue Interaction XI - Photochemical, Photothermal, and Photomechanical CY JAN 22-27, 2000 CL SAN JOSE, CA SP USAF Off Sci Res, SPIE, Int Biomed Opt Soc DE acoustic; ultrasound; drug delivery AB Optically generated acoustic waves have been used to temporarily permeate biological cells. This technique may be useful for enhancing transfection of DNA into cells or enhancing the absorption of locally delivered drugs. A diode-pumped frequency-doubled Nd:YAG laser operating at kHz repetition rates was used to produce a series of acoustic pulses. An acoustic wave was formed via thermoelastic expansion by depositing laser radiation into an absorbing dye. Generated pressures were measured with a PVDF hydrophone. The acoustic waves were transmitted to cultured and plated cells. The cell media contained a selection of normally-impermeable fluorescent-labeled dextran dyes. Following treatment with the opto-acoustic technique, cellular incorporation of dyes, up to 40,000 Molecular Weight, was noted. Control cells that did not receive opto-acoustic treatment had unremarkable dye incorporation. Uptake of dye was quantified via fluorescent microscopic analysis. Trypan Blue membrane exclusion assays and fluorescent labeling assays confirmed the vitality of cells following treatment. This method of enhanced drug delivery has the potential to dramatically reduce required drug dosages and associated side effects and enable revolutionary therapies. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Visuri, SR (reprint author), Lawrence Livermore Natl Lab, POB 808,L-399, Livermore, CA 94551 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 0-8194-3530-9 J9 PROC SPIE PY 2000 VL 3914 BP 183 EP 187 DI 10.1117/12.388044 PG 5 WC Engineering, Biomedical; Optics SC Engineering; Optics GA BQ53Q UT WOS:000088674300022 ER PT S AU Kim, BM Stoller, P Reiser, K Eichler, J Yan, M Rubenchik, A Da Silva, L AF Kim, BM Stoller, P Reiser, K Eichler, J Yan, M Rubenchik, A Da Silva, L BE Duncan, DD Hollinger, JO Jacques, SL TI Confocal imaging of biological tissues using second harmonic generation SO LASER-TISSUE INTERACTION XI: PHOTOCHEMICAL, PHOTOTHERMAL, AND PHOTOMECHANICAL SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Laser-Tissue Interaction XI - Photochemical, Photothermal, and Photomechanical CY JAN 22-27, 2000 CL SAN JOSE, CA SP USAF Off Sci Res, SPIE, Int Biomed Opt Soc ID LASER-PULSES AB A confocal microscopy imaging system was devised to selectively detect second harmonic signals generated by biological tissues. Several types of biological tissues were examined using this imaging system, including human teeth, bovine blood vessels, and chicken skin. All these tissues generated strong second harmonic signals. There is considerable evidence that the source of these signals in tissue is collagen. Collagen, the predominant component of most tissues, is known to have second order nonlinear susceptibility. This technique may have diagnostic usefulness in pathophysiological conditions characterized by changes in collagen structure including malignant transformation of nevi, progression of diabetic complications, and abnormalities in wound healing. C1 Lawrence Livermore Natl Lab, Med Technol Program, Livermore, CA 94550 USA. RP Kim, BM (reprint author), Lawrence Livermore Natl Lab, Med Technol Program, Livermore, CA 94550 USA. NR 7 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 0-8194-3530-9 J9 PROC SPIE PY 2000 VL 3914 BP 435 EP 440 DI 10.1117/12.388066 PG 6 WC Engineering, Biomedical; Optics SC Engineering; Optics GA BQ53Q UT WOS:000088674300049 ER PT S AU Demos, SG Balooch, M Marshall, GW Marshall, SJ Gallagher, RR AF Demos, SG Balooch, M Marshall, GW Marshall, SJ Gallagher, RR BE Featherstone, JDB Rechmann, P Fried, D TI Optical spectroscopy study of transparent non-carious human dentin and dentin-enamel junction SO LASERS IN DENTISTRY VI SE PROGRESS IN BIOMEDICAL OPTICS LA English DT Proceedings Paper CT Conference on Lasers in Dentistry VI CY JAN 23-24, 2000 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE dentin; DEJ; laser-induced fluorescence spectroscopy AB Improving our knowledge of the morphology, composition and properties of the dentin, enamel, and the dentin-enamel junction (DEJ) is vital for the development of improved restorative materials and clinical placement techniques, Most studies of dental tissues have used light microscopy for characterization. In our investigation, the spectroscopic properties of normal and non-carious transparent human root dentin, and the dentin-enamel junction were investigated using emission imaging microscopy, and micro-spectroscopy. Experimental results reveal new information on the structural and biochemical characteristics of these dental tissues. C1 Lawrence Livermore Natl Lab, Livermore, CA 94580 USA. RP Demos, SG (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94580 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 1017-2661 BN 0-8194-3526-0 J9 PROG BIOM O PY 2000 VL 1 BP 102 EP 105 PG 4 WC Dentistry, Oral Surgery & Medicine; Optics SC Dentistry, Oral Surgery & Medicine; Optics GA BP95A UT WOS:000086710900015 ER PT J AU Kim, BM Eichler, J Reiser, KM Rubenchik, AM Da Silva, LB AF Kim, BM Eichler, J Reiser, KM Rubenchik, AM Da Silva, LB TI Collagen structure and nonlinear susceptibility: Effects of heat, glycation, and enzymatic cleavage on second harmonic signal intensity SO LASERS IN SURGERY AND MEDICINE LA English DT Article DE polarization; second harmonic generation; ultrashort pulse laser ID FEMTOSECOND LASER-PULSES; NONENZYMATIC GLYCATION; MOLECULAR PACKING; TAIL TENDON; TISSUES; GENERATION; ABLATION; CHAIN; SCAR AB Background and Objective: Helical macromolecules such as collagen and DNA are characterized by nonlinear optical properties, including nonlinear susceptibility. Because collagen is the predominant component of most biological tissues, as well as the major source of second harmonic generation (SHG), it is reasonable to assume that changes in harmonic signal can be attributed to structural changes in collagen. The purpose of this study is to determine whether various modifications of collagen structure affect second harmonic intensity. Study Design/Materials and Methods: SHG was measured in tissues from cows, humans, and chickens. The effects of beam polarization, thermal denaturation, glyco-oxidative damage, and enzymatic cleavage of tissues on second harmonic intensity was studied. Results: The second harmonic intensity differed considerably among different tissues, as did the effect of the incident beam polarization. In structurally modified collagen, SHG was significantly degraded from SHG; in intact collagen. Conclusion: These structural modifications are representative of changes that occur in pathophysiologic conditions such as thermal injury, diabetes, tumor invasion, and abnormal wound healing. The ability to assess these changes rapidly and noninvasively has considerable clinical applicability. SHG analysis might provide a unique tool for monitoring these structural changes of collagen. Published 2000 Wiley-Liss, Inc.(dagger) C1 Univ Calif Lawrence Livermore Natl Lab, Med Technol Program, Livermore, CA 94550 USA. Univ Appl Sci, Tech Fachhsch Berlin, D-13347 Berlin, Germany. Univ Calif Davis, Sch Med, Davis, CA 95616 USA. RP Kim, BM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Med Technol Program, 7000 East Ave,L-399, Livermore, CA 94550 USA. NR 21 TC 100 Z9 101 U1 0 U2 7 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0196-8092 J9 LASER SURG MED JI Lasers Surg. Med. PY 2000 VL 27 IS 4 BP 329 EP 335 DI 10.1002/1096-9101(2000)27:4<329::AID-LSM5>3.0.CO;2-C PG 7 WC Dermatology; Surgery SC Dermatology; Surgery GA 366PG UT WOS:000090013300005 PM 11074509 ER PT S AU Creutz, M AF Creutz, M BE Mitrjushkin, V Schierholz, G TI Remarks on domain-wall fermions SO LATTICE FERMIONS AND STRUCTURE OF THE VACUUM SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT Conference of the NATO Advanced Research Workshop on Lattice Fermions and Structure of the Vacuum CY OCT 05-09, 1999 CL JOINT INST NUCL RES, DUBNA, RUSSIA SP NATO, Heisenberg Landau Program HO JOINT INST NUCL RES ID LATTICE; FORMULATION; SYMMETRY; STATES C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Creutz, M (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-6429-5 J9 NATO ADV SCI I C-MAT PY 2000 VL 553 BP 1 EP 9 PG 9 WC Mathematics, Applied; Physics, Particles & Fields; Physics, Mathematical SC Mathematics; Physics GA BR58L UT WOS:000166854800001 ER PT S AU Edwards, RG Heller, UM Kiskis, J Narayanan, R AF Edwards, RG Heller, UM Kiskis, J Narayanan, R BE Mitrjushkin, V Schierholz, G TI Topology and chiral symmetry in QCD with overlap fermions SO LATTICE FERMIONS AND STRUCTURE OF THE VACUUM SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT Conference of the NATO Advanced Research Workshop on Lattice Fermions and Structure of the Vacuum CY OCT 05-09, 1999 CL JOINT INST NUCL RES, DUBNA, RUSSIA SP NATO, Heisenberg Landau Program HO JOINT INST NUCL RES ID DIRAC OPERATOR; GAUGE-THEORIES; LATTICE QCD AB We briefly review(1) the overlap formalism for chiral gauge theories, the overlap Dirac operator for massless fermions and its connection to domain wall fermions. We describe properties of the overlap Dirac operator, and methods to implement it numerically. Finally, we give some examples of quenched calculations of chiral symmetry breaking and topology with overlap fermions. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Edwards, RG (reprint author), Jefferson Lab, 12000 Jefferson Ave,MS 12H2, Newport News, VA 23606 USA. NR 24 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-6429-5 J9 NATO ADV SCI I C-MAT PY 2000 VL 553 BP 53 EP 64 PG 12 WC Mathematics, Applied; Physics, Particles & Fields; Physics, Mathematical SC Mathematics; Physics GA BR58L UT WOS:000166854800005 ER PT S AU Klem, JF Choquette, KD Fischer, AJ Blum, O Geib, KM Naone, RL Galt, D AF Klem, JF Choquette, KD Fischer, AJ Blum, O Geib, KM Naone, RL Galt, D GP IEEE IEEE TI 1.3 mu m InGaAsN quantum well vertical cavity surface emitting lasers on GaAs substrates SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Klem, JF (reprint author), Sandia Natl Labs, POB 5800,MS 0603, Albuquerque, NM 87185 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 127 EP 128 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400064 ER PT S AU Kelly, JF Williams, RM Myers, TL Taubman, MS Sheen, DM Sharpe, SW AF Kelly, JF Williams, RM Myers, TL Taubman, MS Sheen, DM Sharpe, SW GP IEEE IEEE TI Chemical sensing with quantum cascade lasers SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World ID SPECTROSCOPY C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Kelly, JF (reprint author), Pacific NW Natl Lab, MS K5-25,POB 999, Richland, WA 99352 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 191 EP 192 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400096 ER PT S AU Kim, BM Stoller, P Reiser, K Rubenchik, A Da Silva, L AF Kim, BM Stoller, P Reiser, K Rubenchik, A Da Silva, L GP IEEE IEEE TI Polarization-sensitive second harmonic confocal imaging of biological tissues SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World ID LASER-PULSES C1 Univ Calif Lawrence Livermore Natl Lab, Med Technol Program, Livermore, CA 94550 USA. RP Kim, BM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Med Technol Program, 7000 E Ave,L-399, Livermore, CA 94550 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 206 EP 207 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400104 ER PT S AU Shvets, G Fisch, NJ Pukhov, A Meyer-ter-Vehn, J AF Shvets, G Fisch, NJ Pukhov, A Meyer-ter-Vehn, J GP IEEE IEEE TI Superradiant pulse compression using free-carrier plasma SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Shvets, G (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 292 EP 293 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400149 ER PT S AU Choquette, KD Hietala, VM Geib, KM AF Choquette, KD Hietala, VM Geib, KM GP IEEE IEEE TI Hybrid integrated VCSEL and driver arrays for optical interconnects SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Choquette, KD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 424 EP 425 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400214 ER PT S AU Han, J Crawford, MH AF Han, J Crawford, MH GP IEEE IEEE TI Growth and characterization of AlGaInN for UV optoelectronics SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World ID LIGHT-EMITTING-DIODES; VAPOR-PHASE EPITAXY; BUFFER LAYER; GAN; SUBSTRATE; SAPPHIRE 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 13 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 557 EP 558 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400281 ER PT S AU Liu, YW Seminario, M Tomasel, FG Chang, C Rocca, JJ Attwood, DT AF Liu, YW Seminario, M Tomasel, FG Chang, C Rocca, JJ Attwood, DT GP IEEE IEEE TI Observation of high average power soft X-ray laser beam approaching full spatial coherence SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World C1 Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RP Liu, YW (reprint author), Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 633 EP 634 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400319 ER PT S AU Roan, E Rajic, S Datskos, PG AF Roan, E Rajic, S Datskos, PG GP IEEE IEEE TI Optically actuated all optical mechanical switch SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World ID SILICON C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Roan, E (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 7 TC 0 Z9 0 U1 0 U2 4 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 641 EP 642 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400323 ER PT S AU Fischer, AJ Choquette, KD Chow, WW Allerman, AA Geib, KM AF Fischer, AJ Choquette, KD Chow, WW Allerman, AA Geib, KM GP IEEE IEEE TI 5.2 mW single-mode power from a coupled-resonator vertical-cavity laser SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World C1 Sandia Natl Labs, Ctr Cpds Semicond Sci & Technol, Albuquerque, NM 87185 USA. RP Fischer, AJ (reprint author), Sandia Natl Labs, Ctr Cpds Semicond Sci & Technol, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 802 EP 803 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400403 ER PT S AU Hadley, GR Choquette, KD Fischer, AJ Geib, KM Allerman, AA Hindi, JJ AF Hadley, GR Choquette, KD Fischer, AJ Geib, KM Allerman, AA Hindi, JJ GP IEEE IEEE TI High-power single mode operation of hybrid ion-implanted/selectively-oxidized VCSELs SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World C1 Sandia Natl Labs, Ctr Cpds Semicond Sci & Technol, Albuquerque, NM 87185 USA. RP Hadley, GR (reprint author), Sandia Natl Labs, Ctr Cpds Semicond Sci & Technol, POB 5800, Albuquerque, NM 87185 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 804 EP 805 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400404 ER PT S AU Chow, E Lin, SY Wendt, JR Allerman, AA Vawter, GA Zubrzycki, W Johnson, SG Villeneuve, PR Joannopoulos, JD AF Chow, E Lin, SY Wendt, JR Allerman, AA Vawter, GA Zubrzycki, W Johnson, SG Villeneuve, PR Joannopoulos, JD GP IEEE IEEE TI Photonic bandgap waveguides - 2D PBG materials embedded in a GaAs/AlO slab SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World AB A new two-dimensional photonic crystal (2D PC) slab structure was created with a full three-dimensional light confinement. Guided modes with broad bandwidth and high transmission for such PC waveguides and bends are also observed. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Chow, E (reprint author), Sandia Natl Labs, MS 0603,POB 5800, Albuquerque, NM 87185 USA. NR 2 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 842 EP 843 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400423 ER PT S AU Geib, KM Choquette, KD Allerman, AA Hindi, JJ AF Geib, KM Choquette, KD Allerman, AA Hindi, JJ GP IEEE IEEE TI Flip-chip integration of selectively oxidized 850 nm VCSEL arrays SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Geib, KM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 850 EP 851 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400427 ER PT S AU Vawter, GA Baca, AG Chow, WW Hafich, MJ Hjalmarson, HP Loubriel, GM Mar, A O'Malley, MW Zutavern, FJ AF Vawter, GA Baca, AG Chow, WW Hafich, MJ Hjalmarson, HP Loubriel, GM Mar, A O'Malley, MW Zutavern, FJ GP IEEE IEEE TI Performance of semiconductor current filament lasers SO LEOS 2000 - IEEE ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS. 1 & 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 13th Annual Meeting of the IEEE Lasers-and-Electro-Optics-Society CY NOV 13-16, 2000 CL RIO GRANDE, PR SP IEEE, Laser & Electroopt Soc, IEEE, Networking World C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Vawter, GA (reprint author), Sandia Natl Labs, POB 5800,MS 0603, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-5947-X J9 IEEE LEOS ANN MTG PY 2000 BP 874 EP 875 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR17V UT WOS:000165806400439 ER PT S AU Curtis, SB Vazquez, ME Wilson, JW Atwell, W Kim, MHY AF Curtis, SB Vazquez, ME Wilson, JW Atwell, W Kim, MHY BE Slenzka, K Vazquez, M Cucinotta, FA TI Cosmic ray hits in the central nervous system at solar maximum SO LIFE SCIENCES: MICROGRAVITY AND SPACE RADIATION EFFECTS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT F2 6 and F2 5 Symposia of COSPAR Scientific Commission F Held during the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP NASA, European Space Agcy, Deutsch Agentur Raumfahrt, Angellegenheiten GMBH, Comm Space Res ID HUMAN RETINA; GANGLION-CELLS; NEURONS; NUMBER AB It has been suggested that a manned mission to Mars be launched at solar maximum rather than at solar minimum to minimize the radiation exposure to galactic cosmic rays. It is true that the number of hits from highly ionizing particles to critical regions in the brain will be less at solar maximum, and it is of interest to estimate how much less. We present here calculations for several sites within the brain from iron ions (z = 26) and from particles with charge, z, greater than or equal to 15. The same shielding configurations and sites in the brain used in an earlier paper for solar minimum are employed so that direct comparison of results between the two solar activity conditions can be made. A simple pressure-vessel wall and an equipment room onboard a spacecraft are chosen as shielding examples. In the equipment room, typical results for the thalamus are that the probability of any particles with 3 greater than or equal to 15 and from 2.3 percent to 1.3 percent for iron ions. The extra shielding provided in the equipment room makes little difference in these numbers. We conclude that this decrease in hit frequency (less than a factor of two) does not provide a compelling reason to avoid solar minimum for a manned mission to Mars. This conclusion could be revised, however, if a very small number of hits is found to cause critical malfunction within the brain. (C) 2000 COSPAR. Published by Elsevier Science Ltd. C1 Fred Hutchinson Canc Res Ctr, Seattle, WA 98104 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Boeing N Amer Inc, Houston, TX 77058 USA. RP Curtis, SB (reprint author), Fred Hutchinson Canc Res Ctr, 1124 Columbia St, Seattle, WA 98104 USA. FU NIDCR NIH HHS [DE-AC02-98CH10886] NR 17 TC 7 Z9 8 U1 0 U2 1 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 2000 VL 25 IS 10 BP 2035 EP 2040 DI 10.1016/S0273-1177(99)01015-7 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP67D UT WOS:000085822600008 PM 11542854 ER PT S AU Vazquez, ME Kirk, E AF Vazquez, ME Kirk, E BE Slenzka, K Vazquez, M Cucinotta, FA TI In vitro neurotoxic effects of 1 GeV/n iron particles assessed in retinal explants SO LIFE SCIENCES: MICROGRAVITY AND SPACE RADIATION EFFECTS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT F2 6 and F2 5 Symposia of COSPAR Scientific Commission F Held during the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP NASA, European Space Agcy, Deutsch Agentur Raumfahrt, Angellegenheiten GMBH, Comm Space Res ID CENTRAL-NERVOUS-SYSTEM; INORGANIC LEAD; NEURITE GROWTH; NEURAL RETINA; SPACE; APOPTOSIS; HIPPOCAMPAL; OUTGROWTH; NEURONS; CULTURE AB The heavy ion component of the cosmic radiation remains problematic to the assessment of risk in manned space flight. The biological effectiveness of HZE particles has yet to be established, particularly with regard to nervous tissue. Using heavy ions accelerated at the AGS of Brookhaven National Laboratory, we study the neurotoxic effects of iron particles. We exposed retinal explants, taken from chick embryos, to determine the dose response relationships for neurite outgrowth. Morphometric techniques were used to evaluate the in vitro effects of 1 GeV/a iron particles (LET 148 keV/mu m). Iron particles produced a dose-dependent reduction of neurite outgrowth with a maximal effect achieved with a dose of 100 cGy. Doses as low as 10-50 cGy were able to induce reductions of the neurite outgrowth as compared to the control group. Neurite generation is a more sensitive parameter than neurite elongation, suggesting different mechanism of radiation damage in our model. These results showed that low doses/fluences of iron particles could impair the retinal ganglion cells' capacity to generate neurites indicating the highly neurotoxic capability of this heavy charged particle. (C) 2000 COSPAR. Published by Elsevier Science Ltd. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Vazquez, ME (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. FU NIDCR NIH HHS [DE-AC02-98CH10886] NR 25 TC 9 Z9 9 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 2000 VL 25 IS 10 BP 2041 EP 2049 DI 10.1016/S0273-1177(99)01012-1 PG 9 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP67D UT WOS:000085822600009 PM 11542855 ER PT S AU Yang, TC Craise, LM Raju, MR AF Yang, TC Craise, LM Raju, MR BE Slenzka, K Vazquez, M Cucinotta, FA TI Oncogenic transformation of mammalian cells by ultrasoft X-rays and alpha particles SO LIFE SCIENCES: MICROGRAVITY AND SPACE RADIATION EFFECTS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT F2 6 and F2 5 Symposia of COSPAR Scientific Commission F Held during the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP NASA, European Space Agcy, Deutsch Agentur Raumfahrt, Angellegenheiten GMBH, Comm Space Res ID HAMSTER-CELLS; CHINESE-HAMSTER; INACTIVATION; RADIOBIOLOGY; RADIATIONS; MUTATION; V79 AB For a better understanding of oncogenic cell transformation by ionizing radiation, we conducted experiments with ultrasoft X rays and low energy alpha particles. Confluent C3H10T1/2 cells were irradiated by Al-K (1.5 keV) X rays or alpha particles from plutonium through a thin mylar sheet, on which the cells attached and grew. Our results indicated that Al-K X rays were more effective in causing cell inactivation and oncogenic transformation than Co-60 gamma rays but less effective than 1.0 and 3.7 MeV alpha particles. There was no significant difference between 1.0 and 3.7 MeV alpha particles in transforming cells although the latter were slightly more effective than the former in producing lethal effect. These results indicated that track structure is important in causing biological effects by ionizing radiation. (C) 2000 COSPAR. Published by Elsevier Science Ltd. C1 NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Houston, TX 77058 USA. Univ Calif Berkeley, Larence Berkeley Natl Lab, Berkeley, CA USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Yang, TC (reprint author), NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Houston, TX 77058 USA. NR 17 TC 1 Z9 1 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 2000 VL 25 IS 10 BP 2123 EP 2130 DI 10.1016/S0273-1177(99)01064-9 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP67D UT WOS:000085822600019 PM 11542865 ER PT S AU Crawford, MH Han, J Chow, WW Banas, MA Figiel, JJ Zhang, L Shul, RJ AF Crawford, MH Han, J Chow, WW Banas, MA Figiel, JJ Zhang, L Shul, RJ BE Yao, HW Ferguson, IT Schubert, EF TI Design and performance of nitride-based UV LEDs SO LIGHT-EMITTING DIODES: RESEARCH, MANUFACTURING, AND APPLICATIONS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Conference on Light-Emitting Diodes (LEDs) CY JAN 26-27, 2000 CL SAN JOSE, CA SP USA Res Off, AIXTRON Inc, SPIE ID MULTIPLE-QUANTUM WELLS; LIGHT-EMITTING-DIODES; GAN; INGAN; LASER; FILMS AB In this paper, we overview several of the critical materials growth, design and performance issues for nitride-based UV (< 400 nm) LEDs. The critical issue of optical efficiency is presented through temperature-dependent photoluminescence studies of various UV active regions. These studies demonstrate enhanced optical efficiencies for active regions with Incontaining alloys (InGaN, AlInGaN). We discuss the trade-off between the challenging growth of high Al containing alloys (AlGaN, AlGaInN), and the need for sufficient carrier confinement in UV heterostructures. Carrier leakage for various composition AlGaN barriers is examined through a calculation of the total unconfined carrier density in the quantum well system. We compare the performance of two distinct UV LED structures: GaN/AlGaN quantum well LEDs for lambda < 360 nm emission, and InGaN/AlGaInN quantum well LEDs for 370 nm < lambda < 390 nm emission. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Crawford, MH (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 25 TC 2 Z9 2 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 0-8194-3555-4 J9 P SOC PHOTO-OPT INS PY 2000 VL 3938 BP 13 EP 23 DI 10.1117/12.382842 PG 11 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BQ27Y UT WOS:000087782000002 ER PT B AU Sabau, AS Viswanathan, S AF Sabau, AS Viswanathan, S BE Peterson, RD TI Porosity prediction in aluminum A356 alloy castings SO LIGHT METALS 2000 LA English DT Proceedings Paper CT Technical Session on Light Metals 2000 held at the 129th TMS Annual Meeting CY MAR 12-16, 2000 CL NASHVILLE, TN SP Minerals Met Mat Soc ID MICROPOROSITY FORMATION; MUSHY ZONE; FLOW AB A comprehensive methodology that takes into account alloy solidification, shrinkage-driven interdendritic fluid flow, hydrogen precipitation, and porosity evolution has been developed for the prediction of microporosity fraction in aluminum A356 alloy castings. The mathematical models presented are implemented in a computational framework consistent with those of commercial casting codes, allowing them to be easily incorporated in commercial casting simulation software. Examples are presented for two test-plate castings of vastly differing solidification behavior. The analysis of (a) metallographic observations of the pore morphology distribution, (b) computed solid fraction distribution, and (c) computed pressure distribution during solidification is used to explain the pore fraction evolution during solidification. The predictions of porosity distribution are validated by comparison with independent experimental measurements of pore fraction in the test plate castings. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Sabau, AS (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. OI Sabau, Adrian/0000-0003-3088-6474 NR 28 TC 7 Z9 7 U1 0 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-462-3 PY 2000 BP 597 EP 602 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ47E UT WOS:000088436700086 ER PT B AU Han, Q Viswanathan, S AF Han, Q Viswanathan, S BE Peterson, RD TI Microstructure prediction in A356 alloy castings SO LIGHT METALS 2000 LA English DT Proceedings Paper CT Technical Session on Light Metals 2000 held at the 129th TMS Annual Meeting CY MAR 12-16, 2000 CL NASHVILLE, TN SP Minerals Met Mat Soc ID MULTICOMPONENT ALLOYS; DENDRITIC GROWTH; EUTECTIC GROWTH; ARRAY GROWTH; SPACINGS AB As part of a program to develop advanced tooling for the design and optimization of structural A356 aluminum alloy castings, models have been used and developed for predicting microstructural length scales after solidification. The length scales are the primary dendrite size, secondary dendrite arm spacing and cell spacing for the primary aluminum phase and the particle/rod length, diameter and spacing for the silicon phase. Mechanisms governing the growth of these phases are considered in the models. The predictions are compared with independent measurements by other researchers and with data from the literature. A good fit with experimental data is obtained. The results of the models are presented in the form of analytical equations for each of the length scales. The simple form of the equations allows them to be used in the postprocessing step of commercial solidification codes for the prediction of microstructure in shape castings. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Han, Q (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 19 TC 4 Z9 4 U1 2 U2 3 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-462-3 PY 2000 BP 609 EP 614 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ47E UT WOS:000088436700088 ER PT B AU Han, Q Kenik, EA Viswanathan, S AF Han, Q Kenik, EA Viswanathan, S BE Peterson, RD TI Die soldering in aluminum die casting SO LIGHT METALS 2000 LA English DT Proceedings Paper CT Technical Session on Light Metals 2000 held at the 129th TMS Annual Meeting CY MAR 12-16, 2000 CL NASHVILLE, TN SP Minerals Met Mat Soc AB Two types of tests, "dipping" tests and "dip-coating" tests, were carried out on small steel cylinders using pure aluminum and 380 alloy to investigate the mechanism of die soldering during aluminum die casting. Optical and scanning electron microscopy were used to study the morphology and composition of the phases formed during soldering. A soldering mechanism is postulated based on experimental observations. A soldering critical temperature is postulated at which iron begins to react with aluminum to form an aluminum-rich liquid phase and solid intermetallic compounds. When the temperature at the die surface is higher than this critical temperature, the aluminum-rich phase is liquid and joins the die with the casting during the subsequent solidification. The paper discusses the mechanism of soldering for the case of pure aluminum and 380 alloy casting in a steel mold, the factors that promote soldering, and the strength of the bond formed when soldering occurs. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Han, Q (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 10 TC 1 Z9 1 U1 1 U2 6 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-462-3 PY 2000 BP 765 EP 770 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ47E UT WOS:000088436700112 ER PT B AU Liu, P Hornyak, GL Dillon, AC Gennett, T Heben, MJ Turner, JA AF Liu, P Hornyak, GL Dillon, AC Gennett, T Heben, MJ Turner, JA BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI Electrochemical performance of carbon nanotube materials in lithium ion batteries SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div AB Single-walled (SWNT), multi-walled (MWNT) and template-synthesized (TSNT) carbon nanotube materials have been tested as anodes in lithium batteries, MWNTs, made by an are-discharge process, showed reversible capacity of 200 mAh/g and flat profiles similar to those of graphitic carbons. SWNTs, prepared by a laser vaporization method, exhibited lithium intercalation behavior that depended on the preparation conditions. In particular, a high degree of lithium ordering was observed in SWNTs prepared in hydrogen/argon mixtures. TSNTs, formed by chemical vapor deposition (CVD) of propylene gas at 800 degrees C within porous alumina templates membranes, consisted of nanocrystalline and disordered graphite. We found that increasing the diameter of TSNTs from 30 to 90 nm and annealing at 1200 degrees C improved the lithium storage capacity. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Liu, P (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 7 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 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 31 EP 39 PG 7 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200003 ER PT B AU Guidotti, RA Scharrer, GL Reinhardt, FW McKecknie, T AF Guidotti, RA Scharrer, GL Reinhardt, FW McKecknie, T BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI Electrochemical evaluation of thin-film Li-Si anodes prepared by plasma spraying SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div ID ELECTRODES AB Thin-film electrodes of a plasma-sprayed Li-Si alloy were evaluated for use as anodes in high-temperature thermally activated (thermal) batteries. These anodes were prepared using 44% Li/56% Si (w/w) material as feed material in a special plasma-spray apparatus under helium or hydrogen, to protect this air- and moisture-sensitive material during deposition, Anodes were tested in single cells using conventional pressed-powder separators and lithiated pyrite cathodes at temperatures of 400 degrees to 550 degrees C at several different current densities. A limited number of 5-cell battery tests were also conducted. The data for the plasma-sprayed anodes was compared to that for conventional pressed-powder anodes. The performance of the plasma-sprayed anodes was inferior to that of conventional pressed-powder anodes, in that the cell emfs were lower (due to the lack of formation of the desired alloy phases) and the small porosity of these materials severely limited their rate capability. Consequently, plasma-sprayed Li-Si anodes would not be practical for use in thermal batteries. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Guidotti, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 0 Z9 0 U1 1 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 184 EP 193 PG 6 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200017 ER PT B AU Yang, XQ Sun, X McBreen, J AF Yang, XQ Sun, X McBreen, J BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI New findings on the phase transitions in Li1-xCoO2 and Li1-xNiO2 cathode materials during cycling: In situ synchrotron x-ray diffraction studies. SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div ID SECONDARY LITHIUM CELLS; LIXCOO2; R(3)OVER-BAR-M AB We have utilized synchrotron x-ray radiation to perform "in situ" x-ray diffraction studies on Li1-xCoO2 and Li1-xNiO2 cathodes. A C/10 charging rate was used for a Li/Li1-xCoO2 cell. For the Li/Li1-xNiO2 cells, C/13 and C/84 rates were applied. The in situ XRD data were collected during the first charge from 3.5 to 5.2 V. For the Li1-xCoO2 cathode, in the composition range of x=0 to x=0.5, a new intermediate phase H2a was observed in addition to the two expected hexagonal phases H1 and H2. In the region very close to x=0.5, some spectral signatures for the formation of a monoclinic phase M1 were also observed. Further, in the x=0.8 to x=1 region, the formation of a CdI2 type hexagonal phase has been confirmed. However, this new phase is transformed from a CdCl2 type hexagonal phase, rather than from a monoclinic phase M2 as previously reported in the literature. For the Li1-xNiO2 system, by taking the advantage of the high resolution in 2 theta angles through the synchrotron based XRD technique, we were able to identify a two-phase coexistence region of hexagonal phase H1 and H2, which has been mistakenly indexed as a single phase region for monoclinic phase M1. Interesting similarities and differences between these two systems are also discussed. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Yang, XQ (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 8 TC 0 Z9 0 U1 2 U2 5 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 245 EP 256 PG 6 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200023 ER PT B AU Sun, X Yang, XQ McBreen, J Gao, Y Yakovleva, MV Xing, XK Daroux, ML AF Sun, X Yang, XQ McBreen, J Gao, Y Yakovleva, MV Xing, XK Daroux, ML BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI Studies on relationship between structure of over-charge state and thermal, stability for LiNiO2 based cathode materials SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div ID X-RAY-DIFFRACTION; SECONDARY LITHIUM CELLS; ION CELLS; LIXCOO2; R(3)OVER-BAR-M; LI-1-XNIO2; BATTERIES; SAFETY AB A synchrotron x-ray source was used for In Situ x-ray diffraction studies on cathode materials during charge and discharge. Two new cathode materials, LiNi0.75Mg0.125Ti0.125O2 and LiNi0.65Co0.25Mg0.05Ti0.05O2, were studied in comparison with LiNiO2 and LiCo0.2Ni0.8O2. The relationship between the structural changes and thermal stability at over-charged state has been investigated. For the first time, The thermal stability of these materials are related to their structural changes during charge, especially to the formation of a hexagonal phase H3 with collapsed lattice along "c" axis. A hypothesis is proposed that through suppressing the formation of H3 phase when charged above 4.3 V, the thermal stability of the cathode materials can be improved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Sun, X (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 10 TC 0 Z9 0 U1 1 U2 5 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 268 EP 277 PG 4 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200025 ER PT B AU Amine, K Yasuda, H Yamachi, M AF Amine, K Yasuda, H Yamachi, M BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI Olivine LiMePO4 (Me : Co, Cu) as 4.8 V and 2 V positive electrodes materials for lithium batteries SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div ID CATHODE MATERIALS AB Reversible extraction and insertion of lithium from olivine LiCoPO4 at 4.8 V vs. lithium have shown that this material is a good candidate for a high-voltage lithium-ion battery. Electrochemical extraction was limited to 0.64 lithium per formula unit, with a charge capacity of 105 mAh/g and a discharge capacity of 80 mAh/g. In this case, the material retains its structural integrity with a slight contraction of the unit cell upon cycling. The crystallinity of the electrode during charge and discharge processes was not affected, as deduced from the sharpness of the X-ray diffraction peaks of the cycled electrode. However, LiCuPO4 exhibited a larger unit cell, with orthorhombic symmetry different from that of olivine. In this case, lithium could not be extracted, and the material could only be discharged at 2 V giving a large discharge capacity of 600 mAh/g. X-ray diffraction of the fully discharge material showed the formation of Li3PO4 and metallic copper due to a decomposition reaction. The formation of metallic copper could enhance the electronic pathway channel of the electrode during the discharge, making LiCuPO4 a good cathode for primary batteries. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Amine, K (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Amine, Khalil/K-9344-2013 NR 16 TC 1 Z9 1 U1 2 U2 26 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 311 EP 325 PG 5 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200029 ER PT B AU Nagasubramanian, G AF Nagasubramanian, G BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI Fluoro-carbonate solvents for Li-ion cells SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div AB A number of fluoro-carbonate solvents were evaluated as electrolytes for Li-ion cells. These solvents are fluorine analogs of the conventional electrolyte solvents such as dimethyl carbonate, ethylene carbonate, diethyl carbonate in Li-ion cells. Conductivity of single and mixed fluoro carbonate electrolytes containing 1 M LiPF6 was measured at different temperatures. These electrolytes did not freeze at -40 degrees C. We are evaluating currently, the irreversible 1(st) cycle capacity loss in carbon anode in these electrolytes and the capacity loss will be compared to that in the conventional electrolytes. Voltage stability windows of the electrolytes were measured at room temperature and compared with that of the conventional electrolytes. The fluoro-carbon electrolytes appear to be more stable than the conventional electrolytes near Li voltage. Few preliminary electrochemical data of the fluoro-carbonate solvents in full cells are reported in the literature. For example, some of the fluorocarbonate solvents appear to have a wider Voltage window than the conventional electrolyte solvents. For example, methyl 2,2,2 trifluoro ethyl carbonate containing 1 M LiPF6 electrolyte has a decomposition voltage exceeding 6 V vs. Li compared to <5 V for conventional electrolytes. The solvent also appears to be stable in contact with lithium at room temperature. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Nagasubramanian, G (reprint author), Sandia Natl Labs, 2521 Lithium Battery R&D, Albuquerque, NM 87185 USA. NR 5 TC 0 Z9 0 U1 1 U2 6 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 434 EP 439 PG 2 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200041 ER PT B AU Lee, HS Sun, X Yang, XQ McBreen, J Callahan, JH Choi, LS AF Lee, HS Sun, X Yang, XQ McBreen, J Callahan, JH Choi, LS BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI Synthesis of cyclic aza-ether compounds and studies of their use as anion receptors in non-aqueous lithium halide salt solutions SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div ID ION AB A series of new anion receptors, based on cyclic aza-ether compounds, have been synthesized. In all of these cyclic aza-ether compounds, the electron-withdrawing group CF3SO2 was attached to each of the nitrogen atoms. When used as additives, all of them can significantly increase the ionic conductivity if lithium halide salts in THF solutions. This is due to the complexation between these compounds and halide anions. Ionic conductivity studies show that the complexation behavior is related to both the ring structure of the cyclic compounds and the characteristics of the halide anions. X-ray diffraction data show that the characteristics of the complex crystals are different from the pure cyclic aza-ether compounds. New Bragg peaks representing a large d-spacing (similar to 15 Angstrom) are observed for the complex crystals which provides a clear evidence for complexation. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Lee, HS (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 10 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 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 471 EP 479 PG 5 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200046 ER PT B AU McBreen, J Lee, HS Yang, XQ Sun, X AF McBreen, J Lee, HS Yang, XQ Sun, X BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI New polymer and liquid electrolytes for lithium batteries SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div ID ION-PAIR DISSOCIATION; X-RAY-ABSORPTION; ANION RECEPTORS; POLY(ETHYLENE OXIDE); TEMPERATURE-DEPENDENCE; NONAQUEOUS SOLUTIONS; POTASSIUM-SALT; CONDUCTIVITY; COMPLEXES; NACF3SO3 AB All non-aqueous lithium battery electrolytes are Lewis bases that interact with cations. Unlike water, they don't interact with anions. The result is a high degree of ion pairing and the formation of triplets and higher aggregates. This decreases the conductivity and the lithium ion transference and results in polarization losses in batteries. Approaches that have been used to increase ion dissociation in PEO based electrolytes are the use of salts with low lattice energy, the addition of polar plasticizers to the polymer, and the addition of cation complexing agents such as crown ethers or cryptands. Complexing of the anions is a more promising approach since it should increase both ion dissociation and the lithium transference. At Brookhaven National Laboratory (BNL) we have synthesized two new families of neutral anion complexing agents, each based on Lewis acid centers. One is based on electron deficient nitrogen sites on substituted aza-ethers, wherein the hydrogen on the nitrogen is replaced by electron withdrawing groups such as CF3SO3-. The other is based on electron deficient boron sites on borane or berate compounds with various fluorinated aryl or alkyl groups. Some of the borane based anion receptors can promote the dissolution of LIF in several solvents. Several of these compounds, when added in equivalent amounts, produce 1.2 M LiF solutions in DME, an increase in solubility of LiF by six orders of magnitude. Some of these LiF electrolytes have conductivities as high as 6x10(-3) Scm(-1). The LiF electrolytes with borane anion acceptors in PC:EC:DEC solvents have excellent electrochemical stability. This has been demonstrated in small Li/LiMn2O4 cells. C1 Brookhaven Natl Lab, Dept Appl Sci, Mat & Chem Sci Div, Upton, NY 11973 USA. RP McBreen, J (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Mat & Chem Sci Div, Upton, NY 11973 USA. NR 29 TC 1 Z9 1 U1 1 U2 3 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 494 EP 503 PG 8 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200049 ER PT B AU Yang, XQ Lee, HS Sun, X McBreen, J AF Yang, XQ Lee, HS Sun, X McBreen, J BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI Comparative studies of the electrochemical and thermal stability of composite electrolytes for lithium battery using two types of boron-based anion receptors SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div ID ION-PAIR DISSOCIATION; NONAQUEOUS SOLUTIONS; CONDUCTIVITY; SALTS; FAMILY AB Comparative studies were done on two new types of boron based anion receptors, tris(pentafluorophenyl) borane (TFPB) and tris(pentafluorophenyl) berate (TFPBO), regarding conductivity enhancement, electrochemical and thermal stability when used as additives in composite electrolytes for lithium batteries. Both additives enhance the ionic conductivity of electrolytes of simple lithium salts, LiF, CF3CO2Li and C2F5CO2Li in several organic solvents. The electrochemical windows of TPFB based electrolytes in ethylene carbonate (EC)-propylene carbonate (PC)-dimethyl carbonate (DMC) (1:1:3, v/v) are up to 5, 4.76 and 4.96 V for LiF, CF3CO2Li and C2F5CO2Li respectively. TPFBO has lower electrochemical stability compared to TPFB. The thermal stability of purl TFPB is better than TFPBO. The lithium salt complexes have higher thermal stability than these two compounds. TPFB based electrolytes showed high cycling efficiencies and good cycleability when they were tested in Li/LiMn2O4 cells. The capacity retention of the cells using TFPB based electrolytes during multiple cycling is better than those using TFPBO based electrolytes. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Yang, XQ (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 10 TC 1 Z9 1 U1 1 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 540 EP 550 PG 7 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200054 ER PT B AU Richardson, TJ Ross, PN AF Richardson, TJ Ross, PN BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI Redox shuttle additives for overcharge protection in lithium batteries SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div AB Seven new redox shuttle additives with shuttle current onset potentials above 4.2 V vs Li/Li+ are reported, along with diffusion coefficients for the neutral additives. The dependence of the limiting shuttle current on the respective diffusion coefficients of the oxidized and reduced forms of an additive is clarified. Overcharge protection in liquid electrolyte Li/LiMn2O4 cells is demonstrated. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Richardson, TJ (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 8 TC 10 Z9 10 U1 0 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 687 EP 693 PG 3 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200070 ER PT B AU Roth, EP AF Roth, EP BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI Thermal stability of Li-ion cells SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div DE lithium ion cells; lithium cobalt oxide; lithium nickel cobalt oxide; thermal stability; calorimetry; ARC; DSC ID LITHIUM INTERCALATED GRAPHITE; CALORIMETRY; ELECTRODES; BATTERIES AB The thermal stability of Li-ion cells with intercalating carbon anodes and metal oxide cathodes was measured as a function of state of charge and temperature for two advanced cell chemistries. Cells of the 18650 design with LixCoO2 cathodes (commercial SONY cells) and LixNi0.8Co0.2O2 cathodes were measured for thermal reactivity in the open circuit cell condition. Accelerating rate calorimetry (ARC) was used to measure cell thermal runaway as a function of state of charge (SOC). Microcalorimetry was used to measure the time dependence of heat generating side reactions also as a function of SOC. Components of cells were measured using differential scanning calorimetry (DSC) to study the thermal reactivity of the individual electrodes to determine the temperature regimes and conditions of the major thermal reactions. Thermal decomposition of the SEI layer at the anodes was identified as the initiating source for thermal runaway. The cells with LixCoO2 cathodes showed greater sensitivity to SOC and higher accelerating heating rates than seen for the cells with LixNi0.8Co0.2O2 cathodes. Lower temperature reactions starting as low as 40 degrees C were also observed that were SOC dependent but not accelerating. These reactions were also measured in the microcalorimeter and observed to decay over time with a power-law dependence and are believed to result in irreversible capacity loss in the cells. C1 Sandia Natl Labs, Lithium Battery R&D Dept 2521, Albuquerque, NM 87185 USA. RP Roth, EP (reprint author), Sandia Natl Labs, Lithium Battery R&D Dept 2521, POB 5800, Albuquerque, NM 87185 USA. NR 8 TC 0 Z9 0 U1 1 U2 7 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 763 EP 771 PG 3 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200077 ER PT B AU Guidotti, RA Reinhardt, FW AF Guidotti, RA Reinhardt, FW BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI Evaluation of fiber separators for use in thermal batteries SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div AB Fiberglass tape and borosilicate filter discs impregnated with molten LiCl-KCl eutectic were examined for potential use as separators for high-temperature LiSi/LiCl-KCl/FeS2 thermal batteries. Test discs were punched from these materials and evaluated at 400 degrees C in single cells at a steady-state current of 63 mA/cm(2). The performance generally improved with electrolyte loading for most of the materials. Better results were obtained with the filter discs than with the tape. The best overall results were obtained with Whatman GF/A discs. Active lives for cells with these separators were about 85% of the standard cells with pressed-powder separators. More work with other materials and electrolytes over a wider temperature range is underway, along with 5-cell-battery tests.. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Guidotti, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 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 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 772 EP 780 PG 5 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200078 ER PT B AU Guidotti, RA Even, WR AF Guidotti, RA Even, WR BE Surampudi, S Marsh, RA Ogumi, Z Prakash, J TI The effects of laser surface reconstruction of disordered carbons on performance SO LITHIUM BATTERIES, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Lithium Batteries of the 196th Electrochemical-Society Fall Meeting CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Battery Div, Electrochem Soc, Energy Technol Div ID HARD AB The reconstruction of the surface of disordered carbons was examined by heating carbons derived from polymethacrylonitrile (PMAN) and divinylbenzene (DVB) with a pulsed infrared laser in an argon or helium atmosphere, both fluidized and under static conditions. By graphitizing the outer surface of the carbons, it was hoped to reduce the high first-cycle Losses associated with such disordered materials in Li-ion cells. The power to the sample was varied to observed the effects on surface morphology and electrochemical performance in 1M LiPF6/ethylene carbonate-dimethyl carbonate. The use various reactive atmosphere such as ethylene, 2-vinylpyridine, pyrrole, and furfuryl alcohol were also evaluated as an alternative means of hopefully forming a thin graphitic layer on the carbon particles to reduce first-cycle irreversibility. While some improvement was realized, these losses were still unacceptably high. The laser heating did improve the rate capabilities of the carbons, however. More work in this area is necessary to fully understand surface and bulk effects. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Guidotti, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 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 1-56677-248-6 J9 ELEC SOC S PY 2000 VL 99 IS 25 BP 790 EP 799 PG 4 WC Electrochemistry SC Electrochemistry GA BQ33W UT WOS:000088014200080 ER PT B AU Takano, H Wong, SS Harnisch, J Porter, MD AF Takano, H Wong, SS Harnisch, J Porter, MD BE Taylor, SR Hillier, AC Seo, M TI Chemically sensitive scanning force microscopy SO LOCALIZED IN-SITU METHODS FOR INVESTIGATING ELECTROCHEMICAL INTERFACES SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Localized In-Situ Methods for Investigating Electrochemical Interfaces CY OCT 20-21, 1999 CL HONOLULU, HI SP Electrochem Soc, Corros Div ID RESOLUTION; SURFACES; POTENTIOMETRY AB The ability to map the subsurface composition of organic thin films is of vast importance to many areas of electrochemistry (e.g., electrocatalysis, corrosion inhibition, and electroanalysis). This report describes preliminary results that demonstrate the ability of electric force microscopy (EFM) to map compositional differences of organic monolayers buried under a thin (similar to 400 nm) polymeric film. The underlying monolayer was patterned onto a gold surface using the self-assembly of thiols on gold, resulting in alternating domains of different terminal groups. Results show not only that the imaging mechanism exhibits sufficient contrast to function as a mapping concept, but also that such imaging has a lateral resolution of similar to 150 nm. C1 US DOE, Ames Lab, Dept Chem, Ames, IA 50011 USA. RP Takano, H (reprint author), US DOE, Ames Lab, Dept Chem, Ames, IA 50011 USA. NR 24 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 1-56677-251-6 J9 ELEC SOC S PY 2000 VL 99 IS 28 BP 46 EP 54 PG 7 WC Electrochemistry SC Electrochemistry GA BQ24K UT WOS:000087714600005 ER PT B AU Isaacs, HS Jeffcoate, CS Missert, NA Barbour, JC AF Isaacs, HS Jeffcoate, CS Missert, NA Barbour, JC BE Taylor, SR Hillier, AC Seo, M TI Ionic current mapping techniques and applications to aluminum-copper corrosion SO LOCALIZED IN-SITU METHODS FOR INVESTIGATING ELECTROCHEMICAL INTERFACES SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT International Symposium on Localized In-Situ Methods for Investigating Electrochemical Interfaces CY OCT 20-21, 1999 CL HONOLULU, HI SP Electrochem Soc, Corros Div ID PROBE FORCE MICROSCOPY; AA2024-T3 AB Measurements have been made of the aluminum/metal galvanic couple. A wide range of geometries were Investigated varying the areas of anodic and cathodic surfaces and employing specially designed galvanic cells with crevices. In situ ionic current density mapping was used to monitor galvanic corrosion and currents flowing between separated metals was measured. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Isaacs, HS (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 7 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 1-56677-251-6 J9 ELEC SOC S PY 2000 VL 99 IS 28 BP 192 EP 199 PG 6 WC Electrochemistry SC Electrochemistry GA BQ24K UT WOS:000087714600016 ER PT S AU Karnowski, TP Tobin, KW Ferrell, RK Lakhani, F AF Karnowski, TP Tobin, KW Ferrell, RK Lakhani, F BE Tobin, KW TI Content based image retrieval for semiconductor manufacturing SO MACHINE VISION APPLICATIONS IN INDUSTRIAL INSPECTION VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Machine Vision Applications in Industrial Inspection VIII CY JAN 24-26, 2000 CL SAN JOSE, CA SP Soc Imaging Sci & Technol, SPIE DE Content-Based Image Retrieval; semiconductor; yield enhancement; defect detection; automated image retrieval AB In the semiconductor manufacturing environment, defect imagery is used to diagnose problems in the manufacturing line, train automatic defect classification systems, and examine historical data for trends. Image management in semiconductor yield management systems is a growing cause of concern since many facilities collect 3000 to 5000 images each month, with future estimates of 12,000 to 20,000. Engineers at Oak Ridge National Laboratory (ORNL) have developed a semiconductor-specific content-based image retrieval architecture, also known as Automated Image Retrieval (AIR). We review the AIR system approach including the application environment as well as details on image interpretation for content-based image retrieval. We discuss the software architecture that has been designed for flexibility and applicability to a variety of implementation schemes in the fabrication environment. We next describe details of the system implementation including image processing and preparation, database indexing, and image retrieval. The image processing and preparation discussion includes a description of an image processing algorithm which enables a more accurate description of the semiconductor substrate (non-defect area). We also describe the features used that identify the key areas of the defect imagery. The feature indexing mechanisms are described next, including their implementation in a commercial database. Next, the retrieval process is described, including query image processing. Feedback mechanisms, which direct the retrieval mechanism to favor specified retrieval results, are also discussed. Finally, experimental results are shown with a database of over 10,000 images obtained from various semiconductor manufacturing facilities. These results include subjective measures of system performance and timing details for our implementation. C1 Oak Ridge Natl Lab, Image Sci & Machine Vis Grp, Oak Ridge, TN 37831 USA. RP Karnowski, TP (reprint author), Oak Ridge Natl Lab, Image Sci & Machine Vis Grp, POB 2008, Oak Ridge, TN 37831 USA. RI Escarabajal, Juan Antonio/C-5644-2012 NR 18 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 0-8194-3584-8 J9 P SOC PHOTO-OPT INS PY 2000 VL 3966 BP 162 EP 172 DI 10.1117/12.380070 PG 11 WC Computer Science, Artificial Intelligence; Engineering, Industrial; Optics SC Computer Science; Engineering; Optics GA BP95H UT WOS:000086714100017 ER PT S AU Pechersky, MJ Harpring, LJ AF Pechersky, MJ Harpring, LJ BE Tobin, KW TI A True Color Tube Bore Inspection System SO MACHINE VISION APPLICATIONS IN INDUSTRIAL INSPECTION VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Machine Vision Applications in Industrial Inspection VIII CY JAN 24-26, 2000 CL SAN JOSE, CA SP Soc Imaging Sci & Technol, SPIE DE true color; borescope; visual inspection; neural networks; color factor AB A True Color Tube Bore Inspection System (TCTBIS) has been developed to aid in the visual nondestructive examination of the inside surfaces of small bore stainless steel tubes. The instrument was developed to inspect for the presence of contaminants and oxidation on the inner surfaces of these 1.5 to 1.7 millimeter inside diameter tubes. Previously a parameter called the color factor, which can be calculated from the images collected by the TCTBIS, was found to be a good measure of the surface quality in these tubes. The color factor is a global number in the sense that it is calculated for the entire inspection region. Additional algorithms have also been developed to evaluate the tube based on surface inhomogeneities that are indicative of the presence of foreign matter, local chemical attack or other undesirable but localized conditions. These algorithms have been incorporated into an up-to-date apparatus which is described in detail. We have also investigated the feasibility of using artificial intelligence techniques to aid in the interpretation of these defects. Promising results were obtained with a feed forward, back propagation artificial neural network. C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Pechersky, MJ (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 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 0-8194-3584-8 J9 P SOC PHOTO-OPT INS PY 2000 VL 3966 BP 174 EP 183 DI 10.1117/12.380071 PG 10 WC Computer Science, Artificial Intelligence; Engineering, Industrial; Optics SC Computer Science; Engineering; Optics GA BP95H UT WOS:000086714100018 ER PT S AU Tobin, KW Goddard, JS Hunt, MA Hylton, KW Karnowski, TP Simpson, ML Richards, RK Treece, DA AF Tobin, KW Goddard, JS Hunt, MA Hylton, KW Karnowski, TP Simpson, ML Richards, RK Treece, DA BE Tobin, KW TI Accommodating multiple illumination sources in an imaging colorimetry environment SO MACHINE VISION APPLICATIONS IN INDUSTRIAL INSPECTION VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Machine Vision Applications in Industrial Inspection VIII CY JAN 24-26, 2000 CL SAN JOSE, CA SP Soc Imaging Sci & Technol, SPIE DE imaging colorimetry; tristimulus colorimetry; projection onto convex sets; D65 illumination; metal-halide illumination; textile products; rotary screen printing ID SEGMENTATION; SPACES AB Researchers at the Oak Ridge National Laboratory have been developing a method for measuring color quality in textile products using a tri-stimulus color camera system. Initial results of the Imaging Tristimulus Colorimeter (ITC) were reported during 1999. These results showed that the projection onto convex sets (POCS) approach to color estimation could be applied to complex printed patterns on textile products with high accuracy and repeatability. Image-based color sensors used for on-line measurement are not colorimetric by nature and require a non-linear transformation of the component colors based on the spectral properties of the incident illumination, imaging sensor, and the actual textile color. Our earlier work reports these results for a broad-band, smoothly varying D65 standard illuminant, To move the measurement to the on-line environment with continuously manufactured textile webs, the illumination source becomes problematic. The spectral content of these light sources varies substantially from the D65 standard illuminant and can greatly impact the measurement performance of the POCS system. Although absolute color measurements are difficult to make under different illumination, referential measurements to monitor color drift provide a useful indication of product quality. Modifications to the ITC system have been implemented to enable the study of different light sources. These results and the subsequent analysis of relative color measurements will be reported for textile products. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Tobin, KW (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. 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 0-8194-3584-8 J9 P SOC PHOTO-OPT INS PY 2000 VL 3966 BP 194 EP 205 PG 12 WC Computer Science, Artificial Intelligence; Engineering, Industrial; Optics SC Computer Science; Engineering; Optics GA BP95H UT WOS:000086714100020 ER PT S AU Allgood, GO Treece, DA Mee, DK Mooney, LR AF Allgood, GO Treece, DA Mee, DK Mooney, LR BE Tobin, KW TI Textile laser-optical system for inspecting fabric structure and form SO MACHINE VISION APPLICATIONS IN INDUSTRIAL INSPECTION VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Machine Vision Applications in Industrial Inspection VIII CY JAN 24-26, 2000 CL SAN JOSE, CA SP Soc Imaging Sci & Technol, SPIE DE laser-optics; US textile industry; textile inspection; 1-D image fabric reconstruction; automated defect detection; pick measurement device; real-time defect classification AB The American textile industry has lost an estimated 400,000 jobs to offshore competitors since 1980. It is predicted they will lose an additional 600,000 jobs by the year 2002. These losses and their resulting economic threat to the U.S. textile industry can be attributed to the low operating costs of their offshore competition. In order to stem these rising losses, the American textile industry entered into an agreement with the U.S. Department of Energy (DOE) in a program called the American Textile Partnership (AMTEX(TM)). Since the minimum U.S. labor rate is well above that of its offshore competitors, one of the competitive factors the U.S. industry hopes to gain is a higher quality fabric. To facilitate this, a Computer-Aided Fabric Evaluation (CAFE) System has been developed at Oak Ridge National Laboratory (ORNL) and Lockheed Martin Energy Systems, Inc. (LMES). The system is based on a class 3-a laser and a set of cylindrical lenses allowing for I-D imaging of single yarns thrown in the fill direction. It has been designed to be located close to the point of fabric formation providing data and information an structure, patterns, and material defects of the fabric as it is being formed. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Allgood, GO (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 0 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 0-8194-3584-8 J9 P SOC PHOTO-OPT INS PY 2000 VL 3966 BP 270 EP 279 DI 10.1117/12.380081 PG 10 WC Computer Science, Artificial Intelligence; Engineering, Industrial; Optics SC Computer Science; Engineering; Optics GA BP95H UT WOS:000086714100027 ER PT J AU Shih, AJ McSpadden, SB Morris, TO Grant, MB Yonushonis, TM AF Shih, AJ McSpadden, SB Morris, TO Grant, MB Yonushonis, TM TI High speed and high material removal rate grinding of ceramics using the vitreous bond CBN wheel SO MACHINING SCIENCE AND TECHNOLOGY LA English DT Article AB High-speed (up to 127 m/s) and high material removal rate grinding experiments were conducted using a vitreous bond cubic boron nitride (CBN) wheel to investigate the effects of material removal rate, wheel speed, dwell time and truing speed ratio on cylindrical grinding of silicon nitride and zirconia. Experimental results show that operating the grinding wheel at a high surface speed can reduce grinding forces, enable high material removal rates, and achieve a higher grinding ratio (G-ratio). The material removal rate was increased to 9.6 and 7.6 mm(3)/s/mm for zirconia and silicon nitride, respectively, to explore the advantage of using high wheel speeds for cost-effective, high-material-removal-rate grinding of ceramics. Models for specific grinding force vs. the specific material removal rate and G-ratio vs. grinding wheel surface speed were developed based on the experimental results. Overall, this study showed that high grinding wheel surface speed is beneficial to the grinding of ceramics. C1 N Carolina State Univ, Dept Mech & Aerosp Engn, Raleigh, NC 27695 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Cummins Engine Co Inc, Columbus, IN 47201 USA. RP Shih, AJ (reprint author), N Carolina State Univ, Dept Mech & Aerosp Engn, Raleigh, NC 27695 USA. NR 9 TC 11 Z9 12 U1 0 U2 1 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 1091-0344 J9 MACH SCI TECHNOL JI Mach. Sci. Technol. PY 2000 VL 4 IS 1 BP 43 EP 58 DI 10.1080/10940340008945699 PG 16 WC Engineering, Manufacturing; Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 302MM UT WOS:000086369200004 ER PT B AU Moore, JF Hryn, JN Pellin, MJ Calaway, WF Watson, K AF Moore, JF Hryn, JN Pellin, MJ Calaway, WF Watson, K BE Kaplan, HL Hryn, JN Clow, BB TI An inert metal anode for magnesium electrowinning SO MAGNESIUM TECHNOLOGY 2000 LA English DT Proceedings Paper CT Magnesium Technology 2000 Symposium held at the 2000 TMS Annual Meeting CY MAR 12-16, 2000 CL NASHVILLE, TN SP Minerals Met & Mat Soc, Light Met Div, Int Magnesium Assoc ID OXYGEN AB Results from the development of a novel type of anode for electrowinning Mg are reported. A tailored alloy system based on the binary Cu-Al can be made to form a thin alumina layer on its surface that is relatively impervious to attack by the molten chloride melt at high temperature. This barrier is thin enough (5-50nm) to conduct electrical current without significant IR loss. As the layer slowly dissolves, the chemical potential developed at the surface drives the diffusion of aluminum from the bulk alloy to reform (heal) the protective alumina layer. In this way, an anode that generates Cl-2 (melt electrolysis) and O-2 (wet feed hydrolysis) and no chlorocarbons can be realized. Further, we expect the rate of loss of the anode to be dramatically less than the coke-derived carbon anodes typically in use for this technology, leading to substantial cost savings and ancillary pollution control by eliminating coke plant emissions, as well as eliminating chlorinated hydrocarbon emissions from Mg electrowinning cells. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Moore, JF (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Pellin, Michael/B-5897-2008 OI Pellin, Michael/0000-0002-8149-9768 NR 12 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 0-87339-466-6 PY 2000 BP 21 EP 26 PG 6 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Metallurgy & Metallurgical Engineering; Materials Science GA BQ46X UT WOS:000088421500004 ER PT B AU Agnew, SR Liu, KC Kenik, EA Viswanathan, S AF Agnew, SR Liu, KC Kenik, EA Viswanathan, S BE Kaplan, HL Hryn, JN Clow, BB TI Tensile and compressive creep behavior of die cast magnesium alloy AM60B SO MAGNESIUM TECHNOLOGY 2000 LA English DT Proceedings Paper CT Magnesium Technology 2000 Symposium held at the 2000 TMS Annual Meeting CY MAR 12-16, 2000 CL NASHVILLE, TN SP Minerals Met & Mat Soc, Light Met Div, Int Magnesium Assoc ID PRISMATIC GLIDE; TEMPERATURE; CERAMICS; INSITU; STRESS AB In an effort to determine the best course for developing die cast alloys with improved creep resistance, the creep behavior of existing commercial alloys is being studied. For many automotive applications under consideration, such as bolted housings and covers, the critical loads are compressive. In spite of this fact, most creep testing has been performed in a tensile mode. In this study we compare the tensile and compressive creep behavior of die cast alloy AM60B at 150 degrees C. The behavior is typical of magnesium alloys in this temperature range. For intermediate tensile stresses (20-60 MPa), a power law with a stress exponent n approximate to 4 describes the stress dependence of the minimum strain rate. The same power law dependence is observed in compression, however, the rates themselves are about an order of magnitude lower. The presence of porosity in the die casting may explain this observation. Although the secondary creep rates at a given stress were slightly lower than those reported for AZ91D, there appears to be more transient creep. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Agnew, SR (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 20 TC 24 Z9 25 U1 0 U2 4 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-466-6 PY 2000 BP 285 EP 290 PG 6 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Metallurgy & Metallurgical Engineering; Materials Science GA BQ46X UT WOS:000088421500039 ER PT B AU Iskander, SK Nanstad, RK Viswanathan, S Swain, RL Wallace, JF AF Iskander, SK Nanstad, RK Viswanathan, S Swain, RL Wallace, JF BE Kaplan, HL Hryn, JN Clow, BB TI Fracture toughness of magnesium alloy AM60B SO MAGNESIUM TECHNOLOGY 2000 LA English DT Proceedings Paper CT Magnesium Technology 2000 Symposium held at the 2000 TMS Annual Meeting CY MAR 12-16, 2000 CL NASHVILLE, TN SP Minerals Met & Mat Soc, Light Met Div, Int Magnesium Assoc AB The fracture toughness of magnesium alloy AM60B was measured using 5-mm-thick compact tension specimens. Characterization of the fracture toughness behavior included tests in two different orientations and three temperatures. Scanning electron microscopy of fracture surfaces and metallography of surfaces parallel to the different orientations were performed to document the results. The fracture toughness tests indicated stable tearing behavior, and testing was discontinued when crack extension exceeded the clip gage capacity. Values of the Tearing Modulus and J(Q) were measured. These two parameters did not reveal any effect of specimen orientation on fracture toughness. Fracture surfaces on some of the tested compact tension specimens showed some porosity, which did not influence the fracture toughness values measured because the direction of crack-propagation was not influenced by the orientation of the porosity. Sub-size Charpy specimens were prepared in the same two orientations in which compact specimens were tested, as well as in other orientations in which compact tension specimens could not be prepared. Charpy impact testing also confirmed that the fracture toughness is generally independent of orientation effects. Force versus displacement traces from Charpy testing also confirmed the stable-tearing behavior observed in fracture toughness testing. Fracture toughness values would help designers choose from among the different materials if service-related experience indicates that better fracture toughness is desirable. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Iskander, SK (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 3 TC 2 Z9 3 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-466-6 PY 2000 BP 325 EP 329 PG 5 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Metallurgy & Metallurgical Engineering; Materials Science GA BQ46X UT WOS:000088421500045 ER PT B AU Agnew, SR Yoo, MH AF Agnew, SR Yoo, MH BE Kaplan, HL Hryn, JN Clow, BB TI Using deformation-induced texture as an alloy/process optimization tool SO MAGNESIUM TECHNOLOGY 2000 LA English DT Proceedings Paper CT Magnesium Technology 2000 Symposium held at the 2000 TMS Annual Meeting CY MAR 12-16, 2000 CL NASHVILLE, TN SP Minerals Met & Mat Soc, Light Met Div, Int Magnesium Assoc ID HEXAGONAL SYMMETRY; PRISMATIC GLIDE; ALLOYS; MAGNESIUM; ZIRCONIUM; EVOLUTION; TITANIUM; INSITU; ZINC AB An approach to alloy/process design for wrought alloys is introduced, and current results of this approach to the magnesium system are presented. In this approach, measurements of deformation texture are used to probe dislocation slip mode activity. The importance of c+a slip for generalized plasticity of hexagonal close packed metals is emphasized; and a connection between c+a and prismatic a slip is proposed via a source mechanism. Solid solution alloys containing lithium or yttrium are shown to have dramatically improved compressive strains to failure over pure magnesium (up to 3 times greater). This result is discussed in view of deformation texture development, and the potential role of c+a slip. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Agnew, SR (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 34 TC 5 Z9 5 U1 2 U2 4 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-466-6 PY 2000 BP 331 EP 339 PG 9 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Metallurgy & Metallurgical Engineering; Materials Science GA BQ46X UT WOS:000088421500046 ER PT S AU Elphic, RC Bonnell, J Strangeway, RJ Carlson, CW Temerin, M McFadden, JP Ergun, RE Peria, W AF Elphic, RC Bonnell, J Strangeway, RJ Carlson, CW Temerin, M McFadden, JP Ergun, RE Peria, W BE Ohtani, S Fujii, R Hesse, M Lysak, RL TI FAST observations of upward accelerated electron beams and the downward field-aligned current region SO MAGNETOSPHERIC CURRENT SYSTEMS SE GEOPHYSICAL MONOGRAPH SERIES LA English DT Proceedings Paper CT Conference on Magnetospheric Current Systems CY JAN 10-15, 1999 CL KONA, HI SP Amer Geophys Union, Natl Sci Fdn, NASA, USN Off Naval Res ID AURORAL CURRENT REGION; SATELLITE-OBSERVATIONS; BIRKELAND CURRENTS; ZONE; ALTITUDES; DE-1 AB Auroral processes result from the exchange of energy and momentum between the magnetosphere and ionosphere, and the current systems arising from this exchange. Field-aligned potential drops in the upward field-aligned current (FAC) region of the auroral zone maintain a required current density in the face of opposing mirror forces. But field-aligned potential drops occur in downward current regions as well, and result in upgoing accelerated electron beams. We investigate the occurrence of upward accelerated electrons with altitude, magnetic local time and season using FAST. By choosing orbits having perigee over the equator, northern-southern hemisphere differences in altitude coverage are largely removed. For an interval near solstice, no electron beams were observed over the summer auroral zone at FAST altitudes, while over the winter hemisphere, 71% of the crossings had upgoing beams, a clear seasonal effect. During the equinox interval the distribution between hemispheres was much more balanced, but the overall occurrence was less (similar to46%) than during winter solstice. There is a clear tendency for upgoing accelerated electron beam occurrence at FAST altitudes to maximize when dipole tilt places the field line footpoint deep in the nightside ionosphere, where background ionospheric density is lowest. In other words, as ionospheric density decreases, the potential structure tends to move to lower altitudes. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Elphic, RC (reprint author), Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. NR 19 TC 20 Z9 20 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0065-8448 BN 0-87590-976-0 J9 GEOPH MONOG SERIES PY 2000 VL 118 BP 173 EP 180 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA BV01G UT WOS:000177598400016 ER PT S AU Birn, J Hesse, M AF Birn, J Hesse, M BE Ohtani, S Fujii, R Hesse, M Lysak, RL TI The current disruption myth SO MAGNETOSPHERIC CURRENT SYSTEMS SE GEOPHYSICAL MONOGRAPH SERIES LA English DT Proceedings Paper CT Conference on Magnetospheric Current Systems CY JAN 10-15, 1999 CL KONA, HI SP Amer Geophys Union, Natl Sci Fdn, NASA, USN Off Naval Res ID FIELD-ALIGNED CURRENTS; SUBSTORM CURRENT WEDGE; THIN CURRENT SHEETS; MAGNETOSPHERIC SUBSTORMS; GROWTH-PHASE; MAGNETOTAIL RECONNECTION; TAIL; SIMULATIONS; DIVERSION; DYNAMICS AB We investigate signs and symptoms of current disruption and diversion on the basis of resistive MHD simulations of magnetotail dynamics. The simulations generally support the view that the local occurrence of anomalous dissipation (here modeled by a resistive term) leads to the reduction (disruption) and diversion of cross-tail current. However, the dynamic relation between the occurrence of resistivity and its effects differs from views originally derived from circuit analogies. The primary myth addressed here is the expectation that current disruption is the direct consequence of anomalously enhanced dissipation, so that the current disruption region and the dissipation region should be collocated. We find that the initial consequence of enhanced resistance indeed is a reduction of the local cross-tail current threading the region of enhanced resistance. However, this local reduction is accompanied by a diversion of current around that region, so that there are no global consequences. The later, more global, current changes result from the plasma dynamics (flows) rather than from the local dissipation. Hence the region of reduced cross-tail current is distinct (located earthward) from the region of enhanced resistivity. The region of dipolarization, the most commonly considered indicator of current disruption, again is distinct from the region of current reduction. This region expands in all three space directions, which might affect the timing between satellites. The energy changes are consistent with the expected conversion of magnetic into kinetic and thermal energy. However, these processes are not highly localized and the release or conversion regions also are not collocated with the region of enhanced resistivity. C1 Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. RP Birn, J (reprint author), Los Alamos Natl Lab, Space & Atmospher Sci Grp, MS D466, Los Alamos, NM 87545 USA. RI Hesse, Michael/D-2031-2012 NR 36 TC 5 Z9 5 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0065-8448 BN 0-87590-976-0 J9 GEOPH MONOG SERIES PY 2000 VL 118 BP 285 EP 294 PG 10 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA BV01G UT WOS:000177598400029 ER PT J AU Simpson, EH Suffolk, R Bell, JA Jordan, SA Johnson, DK Hunsicker, PR Weber, JS Justice, MJ Jackson, IJ AF Simpson, EH Suffolk, R Bell, JA Jordan, SA Johnson, DK Hunsicker, PR Weber, JS Justice, MJ Jackson, IJ TI A comparative transcript map and candidates for mutant phenotypes in the Tyrp1 (brown) deletion complex homologous to human 9p21-23 SO MAMMALIAN GENOME LA English DT Article ID MOUSE CHROMOSOME-4; HUMAN GENOME; MOLECULAR-GENETICS; (B)-LOCUS REGION; SECRETED FACTOR; LOCUS TEST; CERBERUS; MICE; DUPLICATION; ENDODERM AB The mouse Trp1 deletion complex is a valuable resource for high-resolution mapping of genes and phenotypes to the central region of Chromosome (Chr) 4. The distal part of the complex is homologous to human Chr 9p21-23, and we have used the available radiation hybrid maps to identify human transcripts in the region. We localize seven genes to a human YAC contig that spans the full extent of the distal deletion complex and show that the mouse homologs of four of these, including Cer1, map within the complex. On the basis of location and/or expression, we exclude genes as candidates for several known phenotypes in the region and identify a candidate transcript for the neonatal lethal phenotype l(4)Rn2. C1 Western Gen Hosp, MRC, Human Genet Unit, Edinburgh EH4 2XU, Midlothian, Scotland. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. RP Jackson, IJ (reprint author), Western Gen Hosp, MRC, Human Genet Unit, Crewe Rd, Edinburgh EH4 2XU, Midlothian, Scotland. NR 33 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0938-8990 J9 MAMM GENOME JI Mamm. Genome PD JAN PY 2000 VL 11 IS 1 BP 58 EP 63 DI 10.1007/s003350010011 PG 6 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity GA 267EU UT WOS:000084344800011 PM 10602994 ER PT J AU Kooyman, GL Hunke, EC Ackley, SE van Dam, RP Robertson, G AF Kooyman, GL Hunke, EC Ackley, SE van Dam, RP Robertson, G TI Moult of the emperor penguin: travel, location, and habitat selection SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE satellite transmitter; Antarctica; Ross Sea; Weddell Sea; Amundsen Sea; pack-ice ID SPHENISCUS-DEMERSUS AB All penguins except emperors Aptenodytes forsteri and Adelies Pygoscelis adeliae moult on land, usually near the breeding colonies. These 2 Antarctic species typically moult some where in the pack-ice. Emperor penguins begin their moult in early summer when the pack-ice cover of the Antarctic Ocean is receding. The origin of the few moulting birds seen by observers on passing ships is unknown, and the locations are often far from any known colonies. We attached satellite transmitters to 12 breeding adult A. forsteri from western Ross Sea colonies before they departed the colony for the last time before moulting. In addition, we surveyed some remote areas of the Weddell Sea north and east of some large colonies that are located along the southern and western borders of this sea. The tracked birds moved at a rate of nearly 50 km d(-1) for more than 1000 km over 30 d to reach areas of perennially consistent pack-ice. Almost all birds traveled to the eastern Ross Sea and western Amundsen Sea. Sea-ice conditions were observed directly in the Weddell Sea from ship and helicopter. Most flees selected for moulting were ridged, and usually >100 m(2). From these observations we predict where the most likely moult refuges are for emperor penguins from other colonies around the Antarctic continent. C1 Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. USA, Cold Reg Res & Engn Lab, Hanover, NH 03755 USA. Australian Antarctic Div, Kingston, Tas 7050, Australia. RP Kooyman, GL (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, Scholander Hall,0204, La Jolla, CA 92093 USA. EM gkooyman@ucsd.edu NR 15 TC 26 Z9 26 U1 2 U2 16 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PY 2000 VL 204 BP 269 EP 277 DI 10.3354/meps204269 PG 9 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA 365GW UT WOS:000089943900022 ER PT J AU Johnson, RC Cooks, RG Allen, TM Cisper, ME Hemberger, PH AF Johnson, RC Cooks, RG Allen, TM Cisper, ME Hemberger, PH TI Membrane introduction mass spectrometry: Trends and applications SO MASS SPECTROMETRY REVIEWS LA English DT Review DE membrane introduction mass spectrometry; environmental analysis; bioreactor monitoring; semipermeable membranes; semivolatiles; on-line analysis; physiological monitoring; direct introduction mass spectrometry; chromatography ID VOLATILE ORGANIC-COMPOUNDS; FUNGUS BJERKANDERA-ADUSTA; PER-TRILLION LEVELS; AQUEOUS-SOLUTION; NITRIC-OXIDE; SELECTIVE INTRODUCTION; ENVIRONMENTAL-ANALYSIS; TRICHOMONAS-VAGINALIS; CHEMICAL-IONIZATION; SORBENT INTERFACE AB Recent advances in membrane introduction mass spectrometry (MIMS) are reviewed. On-line monitoring is treated by focusing on critical variables, including the nature and dimensions of the membrane, and the analyte vapor pressure, diffusivity, and solubility in the membrane barrier Sample introduction by MIMS is applied in (i) on-line monitoring of chemical and biological reactors, (ii) analysis of volatile organic compounds in environmental matrices, including ail; water and soil, and (iii) in more fundamental studies, such as measurements of thermochemical properties, reaction mechanisms, and kinetics. New semipermeable membranes are discussed, including those consisting of thin polymers, low vapor pressure liquids, and zeolites. These membranes have been used to monitor polar compounds, selectively differentiate compounds through affinity-binding, and provide isomer differentiation based on molecular size. Measurements at high spatial resolution, for example, using silicone-capped hypodermic needle inlets, are also covered, as is electrically driven sampling through microporous membranes. Other variations on the basic MIMS experiment include analyte preconcentration through cryotrapping (CT-MIMS) or trapping in the membrane (trap-and-release), as well as differential thermal release methods and reverse phase (i.e., organic solvent) MMS. Method limitations center on semivolatile compounds and complex mixture analysis, and novel solutions are discussed. Semivolatile compounds have been monitored with thermally assisted desorption, ultrathin membranes and derivatization techniques. Taking advantage of the differences in time of membrane permeation, mixtures of structurally similar compounds have been differentiated by using sample modulation techniques and by temperature-programmed desorption from a membrane interface. Selective ionization techniques that increase instrument sensitivity towards polar compounds are also described, and comparisons are made with other direct sampling (nonchromatographic) methods that are useful in mixture analysis. (C) 2000 John Wiley & Sons, Inc. C1 Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Nonproliferat & Int Secur Div, Los Alamos, NM 87545 USA. RP Cooks, RG (reprint author), Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. RI Bueno, Ligia/P-1359-2014; Cooks, R/G-1051-2015 OI Cooks, R/0000-0002-9581-9603 NR 145 TC 153 Z9 157 U1 14 U2 83 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0277-7037 EI 1098-2787 J9 MASS SPECTROM REV JI Mass Spectrom. Rev. PD JAN-FEB PY 2000 VL 19 IS 1 BP 1 EP 37 DI 10.1002/(SICI)1098-2787(2000)19:1<1::AID-MAS1>3.0.CO;2-Y PG 37 WC Spectroscopy SC Spectroscopy GA 288ER UT WOS:000085549700001 PM 10715830 ER PT J AU Dane, CB Hackel, LA Daly, J Harrisson, J AF Dane, CB Hackel, LA Daly, J Harrisson, J TI High power laser for peening of metals enabling production technology SO MATERIALS AND MANUFACTURING PROCESSES LA English DT Article AB Laser shot peening, a surface treatment for metals, is known to induce compressive residual stresses of over 1 mm (0.040 inch) depth providing improved component resistance to various forms of failure. Additionally recent information suggests that thermal relaxation of the laser induced stress is significantly less than that experienced by other forms of surface stressing that involve significantly higher levels of cold work. We have developed a unique solid state laser technology employing Nd:glass slabs and phase conjugation that enables this process to move into high throughput production processing. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Met Improvement Corp, Paramus, NJ 07652 USA. NR 12 TC 11 Z9 12 U1 2 U2 5 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 1042-6914 J9 MATER MANUF PROCESS JI Mater. Manuf. Process. PY 2000 VL 15 IS 1 BP 81 EP 96 DI 10.1080/10426910008912974 PG 16 WC Engineering, Manufacturing; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 283VM UT WOS:000085296800005 ER PT J AU Milewski, JO Lewis, GK Fonseca, J Nemec, RB AF Milewski, JO Lewis, GK Fonseca, J Nemec, RB TI Laser powder deposition of a near net shape injection mold core - A case study SO MATERIALS AND MANUFACTURING PROCESSES LA English DT Article ID DIRECTED LIGHT FABRICATION AB Directed Light Fabrication (DLF) is a direct deposition process that fuses metal powder, in the focal zone of a laser beam, to form fully fused near net shaped components. A fully associative 3D design-through-manufacturing model is presented as a case study for the fabrication of a near net shaped injection mold core part. This study evaluates the ability to move from a parametric 3D model, integrated into a manufacturing model, to creating a control file used to produce a component using a nickel base alloy. Evaluation of the efficiency, quality, attributes and limitations of the process is reported. A high degree of accuracy for large feature location was obtained but improvements in surface finish and the dimensional accuracy of small features are required to fully realize benefits of this technology. The competing benefits of deposition accuracy and manufacturing time are discussed in terms of computerized numerical control code generation. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. NR 12 TC 9 Z9 9 U1 2 U2 4 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 1042-6914 J9 MATER MANUF PROCESS JI Mater. Manuf. Process. PY 2000 VL 15 IS 2 BP 247 EP 258 DI 10.1080/10426910008912986 PG 12 WC Engineering, Manufacturing; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 299TP UT WOS:000086214200007 ER PT J AU Hou, PY Smialek, JL AF Hou, PY Smialek, JL TI The effect of H(2)-anneal on the adhesion of Al(2)O(3) scales on a Fe(3)Al-based alloy SO MATERIALS AT HIGH TEMPERATURES LA English DT Article; Proceedings Paper CT 4th International Conference on the Microscopy of Oxidation CY SEP 20-22, 1999 CL CAMBRIDGE, ENGLAND DE Fe(3)Al; Al(2)O(3); adhesion; sulfur segregation; reactive element ID REACTIVE ELEMENT; SULFUR; SEGREGATION; ADHERENCE; ALUMINA; GROWTH AB The cyclic (1,100 degrees C, air) and isothermal (1,000 degrees C, O(2)) oxidation behavior of a Fe-28Al-5Cr (at%) alloy, with and without a prior H(2)-anneal heat treatment at 1,200 degrees C for 100 h, was studied. Changes in interfacial chemistry were evaluated using Scanning Anger Microscopy after removal of the oxide film in ultra high vacuum. This was achieved by making a scratch on the specimen surface, which caused spallation of the film at various locations along the scratch. The scale thickness and the temperature drop at which spallation took place during cooling were utilized to semi-quantitatively compare the adherence of the scales. Porosity at the scale-alloy interface and the scale microstructure were determined from scanning electron microscope observations. It was found that H(2)-anneal greatly improved scale adhesion and resulted in a pore-free and sulfur-free interface. The effects were similar to that of a 0.1 at% Zr-containing alloy, except that the improvement in scale adhesion was not as great as that from Zr doping. This implies that oxide/alloy interfaces are not intrinsically strong and the effect of reactive elements, such as Zr, is more than preventing impurity from segregating to the interface. Results are also compared with the effect of H(2)-anneal on other model alloys, such as NiCrAl, FeCrAl and NiAl, and on single crystal superalloys. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. RP Hou, PY (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 25 TC 24 Z9 24 U1 0 U2 6 PU SCIENCE REVIEWS 2000 LTD PI ST ALBANS PA PO BOX 314, ST ALBANS AL1 4ZG, HERTS, ENGLAND SN 0960-3409 J9 MATER HIGH TEMP JI Mater. High Temp. PY 2000 VL 17 IS 1 BP 79 EP 85 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 318NU UT WOS:000087291000013 ER PT J AU Pint, BA More, KL Wright, IG Tortorelli, PF AF Pint, BA More, KL Wright, IG Tortorelli, PF TI Characterization of thermally cycled alumina scales SO MATERIALS AT HIGH TEMPERATURES LA English DT Article; Proceedings Paper CT 4th International Conference on the Microscopy of Oxidation CY SEP 20-22, 1999 CL CAMBRIDGE, ENGLAND DE alumina scales; nickel; chromium ID OXIDATION BEHAVIOR; ION-IMPLANTATION; CR-AL; ALPHA-AL2O3; GROWTH; ALLOYS; SEGREGATION; MORPHOLOGY; ADHESION; CHROMIUM AB Cross-sectional transmission electron microscopy was used to characterize the alumina scales formed on several Ni-base alumina-formers. The alumina scale microstructure of Ni-20at%Cr-19Al-0.05Y after 100, 1 h cycles at 1,100 degrees C was compared to an isothermally-grown scale. Despite being near the onset of mass loss in cyclic testing, very few defects were noted in either scale microstructure. The more adherent scales that form on Hf-doped NiAl and Ni-49at%Al-2Cr were also characterized. With the addition of Cr, the formation of alpha-Cr precipitates at the metal-oxide interface coincided with increased long-term scale spallation. No similar precipitation mechanism was observed to be associated with scale spallation on NiCrAlY. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Pint, BA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Wright, Ian/A-8300-2008; Pint, Bruce/A-8435-2008; Tortorelli, Peter/E-2433-2011; More, Karren/A-8097-2016 OI Pint, Bruce/0000-0002-9165-3335; More, Karren/0000-0001-5223-9097 NR 41 TC 24 Z9 24 U1 0 U2 4 PU SCIENCE REVIEWS 2000 LTD PI ST ALBANS PA PO BOX 314, ST ALBANS AL1 4ZG, HERTS, ENGLAND SN 0960-3409 J9 MATER HIGH TEMP JI Mater. High Temp. PY 2000 VL 17 IS 1 BP 165 EP 171 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 318NU UT WOS:000087291000024 ER PT J AU Brady, MP Tortorelli, PF Walker, LR AF Brady, MP Tortorelli, PF Walker, LR TI Correlation of alloy microstructure with oxidation behavior in chromia-forming intermetallic-reinforced Cr alloys SO MATERIALS AT HIGH TEMPERATURES LA English DT Article; Proceedings Paper CT 4th International Conference on the Microscopy of Oxidation CY SEP 20-22, 1999 CL CAMBRIDGE, ENGLAND DE Cr; Laves phase; chromia; nitride; oxidation ID COMPOSITES AB The oxidation behavior of the Cr(X) solid solution and intermetallic Cr(2)X Laves phases (X = Nh, Ta) was studied individually and in combination at 1,100 degrees C in humid air. The two-phase Cr(Ta) + Cr(2)Ta alloys exhibited superior oxidation resistance to either the single-phase Cr(Ta) or the single-phase Cr(2)Ta alloys. However, the two-phase Cr(Nb) + Cr(2)Nb alloys exhibited lower oxidation resistance than either the single-phase Cr(Nb) or Cr(2)Nb alloys. The two-phase Cr(Ta)+ Cr(2)Ta alloys were also found to exhibit superior oxidation resistance to the two-phase Cr(Nb) + Cr(2)Nb alloys. This was hypothesized to be related to the lower amount of the Cr(2)X phase in the Cr(Ta)-Cr(2)Ta eutectic and to the lower solubility of Ta in the Cr(X) phase, relative to the Cr-Nb system. Both of these factors resulted in significantly less oxidation and nitridation in the Cr(Ta) + Cr(2)Ta alloys. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Brady, MP (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM bradymp@ornl.gov RI Brady, Michael/A-8122-2008 OI Brady, Michael/0000-0003-1338-4747 NR 17 TC 10 Z9 11 U1 0 U2 4 PU SCIENCE REVIEWS 2000 LTD PI ST ALBANS PA PO BOX 314, ST ALBANS AL1 4ZG, HERTS, ENGLAND SN 0960-3409 J9 MATER HIGH TEMP JI Mater. High Temp. PY 2000 VL 17 IS 2 BP 235 EP 241 DI 10.3184/096034000783640983 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 344TA UT WOS:000088773900010 ER PT J AU Miller, MK Burke, MG AF Miller, MK Burke, MG TI Atom probe field-ion microscopy: 30 years of atomic-level analysis SO MATERIALS CHARACTERIZATION LA English DT Editorial Material C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Miller, MK (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 0 TC 7 Z9 7 U1 1 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-5803 J9 MATER CHARACT JI Mater. Charact. PD JAN-FEB PY 2000 VL 44 IS 1-2 BP 1 EP 1 DI 10.1016/S1044-5803(99)00064-9 PG 1 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA 278MJ UT WOS:000084993300001 ER PT J AU Miller, MK AF Miller, MK TI The development of atom probe field-ion microscopy SO MATERIALS CHARACTERIZATION LA English DT Article ID IMPLEMENTATION; DETECTOR; DESIGNS AB A review of the development of the techniques of atom probe field-ion microscopy and atom probe tomography is presented. The development is traced from the original time-of-flight atom probe field-ion microscope developed by Muller, Panitz, and McLean in 1968 to the energy-compensated three-dimensional atom probes that are commercially available today. The various types of atom probes that have been developed are described. Published by Elsevier Science Inc. C1 Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, Oak Ridge, TN 37831 USA. RP Miller, MK (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, POB 2008, Oak Ridge, TN 37831 USA. RI Felfer, Peter/H-6024-2011 NR 45 TC 20 Z9 20 U1 0 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-5803 J9 MATER CHARACT JI Mater. Charact. PD JAN-FEB PY 2000 VL 44 IS 1-2 BP 11 EP 27 DI 10.1016/S1044-5803(99)00053-4 PG 17 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA 278MJ UT WOS:000084993300003 ER PT J AU Kelly, TF Larson, DJ AF Kelly, TF Larson, DJ TI Local Electrode Atom Probes SO MATERIALS CHARACTERIZATION LA English DT Article ID FIELD-ION MICROSCOPY; MASS-SPECTROSCOPY; THIN-FILM; SPECTROMETERS; DETECTORS; EMITTERS; ANODES; TIPS AB The historical developments leading to the advent of Local Electrode Atom Probes (LEAP) are reviewed. An assessment of the state of the art is made, and the major advantages of LEAPs over conventional atom probes are described. The best implementations of these concepts and the remaining challenges for realization of LEAP's potential are also described. It is concluded that LEAPs should be an important tool for materials characterization at the atomic scale. Modern materials-dependent industries as diverse as steel and microelectronics should benefit from this technology. (C) Elsevier Science Inc., 2000. All rights reserved. C1 Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53706 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Kelly, TF (reprint author), Univ Wisconsin, Dept Mat Sci & Engn, 1509 Univ Ave, Madison, WI 53706 USA. NR 80 TC 99 Z9 99 U1 0 U2 6 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-5803 J9 MATER CHARACT JI Mater. Charact. PD JAN-FEB PY 2000 VL 44 IS 1-2 BP 59 EP 85 DI 10.1016/S1044-5803(99)00055-8 PG 27 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA 278MJ UT WOS:000084993300005 ER PT J AU Larson, DJ Miller, MK AF Larson, DJ Miller, MK TI Atom probe field-ion microscopy characterization of nickel and titanium aluminides SO MATERIALS CHARACTERIZATION LA English DT Article ID SITE OCCUPATION PROBABILITY; TIAL INTERMETALLIC COMPOUND; RAPIDLY-SOLIDIFIED NI3AL; B-DOPED NI3AL; GRAIN-BOUNDARIES; DEFORMATION MECHANISMS; ALLOYS; BORON; APFIM; PHASE AB A review of the contributions of atom probe field-ion microscopy to the characterization of nickel and titanium aluminides is presented. The nickel aluminide systems studied include boron-doped Ni3Al and boron-, carbon-, beryllium-, zirconium-, molybdenum-, and hafnium-doped NiAl. These systems have been characterized in terms of solute segregation to boundaries, dislocations, and other defects, matrix solubilities, precipitation, and site-occupation probabilities. The partitioning behavior of impurities and alloying additions, matrix solubilities, precipitate compositions, and interfacial segregation in several of alpha(2) + gamma titanium aluminides and related alloys are also reviewed. Published by Elsevier Science Inc. C1 Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, Oak Ridge, TN 37831 USA. RP Larson, DJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, POB 2008, Oak Ridge, TN 37831 USA. NR 81 TC 17 Z9 17 U1 0 U2 10 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1044-5803 EI 1873-4189 J9 MATER CHARACT JI Mater. Charact. PD JAN-FEB PY 2000 VL 44 IS 1-2 BP 159 EP 176 DI 10.1016/S1044-5803(99)00049-2 PG 18 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA 278MJ UT WOS:000084993300009 ER PT J AU Miller, MK Pareige, P Burke, MG AF Miller, MK Pareige, P Burke, MG TI Understanding pressure vessel steels: An atom probe perspective SO MATERIALS CHARACTERIZATION LA English DT Article ID FIELD-ION MICROSCOPY; FE-CU-NI; NEUTRON-IRRADIATION; MICROSTRUCTURAL CHARACTERIZATION; COPPER; PRECIPITATION; ALLOYS; APFIM; EVOLUTION; WELD AB A review of the contributions of the atom probe field-ion microscopy (APFIM) technique to the microstructural characterization of pressure vessel steels and to the understanding of the embrittlement of these materials during neutron irradiation is presented. Atom probe studies have revealed that the microstructure contains a variety of ultrafine clusters and precipitates some of which are only formed during neutron irradiation. Furthermore, there is a complex pattern of segregation of various solutes (including phosphorus, nickel, manganese, or molybdenum) to grain boundaries in some pressure vessel materials, and there may also be additional intergranular precipitation in these materials. Published by Elsevier Science inc. C1 Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, Oak Ridge, TN 37831 USA. Univ Rouen, Fac Sci, CNRS,UMR 6634, Grp Met Phys, F-76128 Mt St Aignan, France. Bechtel Bettis Inc, W Mifflin, PA 15122 USA. RP Miller, MK (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, POB 2008, Oak Ridge, TN 37831 USA. RI PAREIGE, Philippe/A-2588-2013 NR 54 TC 83 Z9 85 U1 0 U2 15 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-5803 J9 MATER CHARACT JI Mater. Charact. PD JAN-FEB PY 2000 VL 44 IS 1-2 BP 235 EP 254 DI 10.1016/S1044-5803(99)00056-X PG 20 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA 278MJ UT WOS:000084993300013 ER PT S AU Curtis, CJ Miedaner, A Rivkin, T Alleman, J Schulz, DL Ginley, DS AF Curtis, CJ Miedaner, A Rivkin, T Alleman, J Schulz, DL Ginley, DS BE Chrisey, DB Gamota, DR Helvajian, H Taylor, DP TI Direct write metallizations for Ag and Al SO MATERIALS DEVELOPMENT FOR DIRECT WRITE TECHNOLOGIES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials Development for Direct Write Technologies CY APR 24-26, 2000 CL SAN FRANCISCO, CA SP Mat Res Soc ID CHEMICAL-VAPOR-DEPOSITION; SOLAR-CELLS; COPPER AB We have employed inks containing nanometer-sized particles of Ag and Al (nano-Ag and nano-Al, respectively) as precursor inks for the formation of contacts to n- and p-type Si, respectively. The particles as formed by the electroexplosion process were dispersed in toluene, applied to Si and annealed above the respective eutectic temperatures. In the case of nano-Ag, this directly yields an ohmic contact. However, the nano-Al was found to be coated with an oxide layer that impairs the formation of an ohmic contact. A chelating chemical etch involving treatment with hexafluoroacetylacetone was developed to remove this oxide coat. This treated nano-Al produced a good ohmic contact. Smooth, pure Ag films have also been deposited by spray printing organometallic inks prepared from Ag(hfa)(SEt2) and Ag(hfa)(COD). These films are deposited in one step onto heated glass and Si substrates at one atmosphere pressure. The films show resistivities of similar to2 mu Omega -cm. These inks appear to be amenable to ink-jet printing of Ag lines and as a low temperature glue for the Ag nanoparticles for thicker metallizations. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Curtis, CJ (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 13 TC 6 Z9 6 U1 1 U2 5 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-532-3 J9 MATER RES SOC SYMP P PY 2000 VL 624 BP 59 EP 64 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA BR97N UT WOS:000168247700010 ER PT S AU Fan, HY Lopez, GP Brinker, CJ AF Fan, HY Lopez, GP Brinker, CJ BE Chrisey, DB Gamota, DR Helvajian, H Taylor, DP TI Rapid prototyping of patterned multifunctional nanostructures SO MATERIALS DEVELOPMENT FOR DIRECT WRITE TECHNOLOGIES SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on Materials Development for Direct Write Technologies CY APR 24-26, 2000 CL SAN FRANCISCO, CA SP Mat Res Soc ID SELF-ASSEMBLED MONOLAYERS; MESOPOROUS SILICA; FILMS; MICROFABRICATION; GOLD AB The ability to engineer ordered arrays of objects on multiple length scales has potential for applications such as microelectronics, sensors, wave guides, and photonic lattices with tunable band gaps. Since the invention of surfactant templated mesoporous sieves in 1992, great progress has been made in controlling different mesophases in the form of powders, particles, fibers, and films. To date, although there have been several reports of patterned mesostructures, materials prepared have been limited to metal oxides with no specific functionality. For many of the envisioned applications of hierarchical materials in micro-systems, sensors, waveguides, photonics, and electronics, it is necessary to define both form and function on several length scales. In addition, the patterning strategies utilized so far require hours or even days for completion. Such slow processes are inherently difficult to implement in commercial environments. We present a series of new methods of producing patterns within seconds. Combining sor-gel chemistry, Evaporation-Induced Self-Assembly (EISA), and rapid prototyping techniques like pen lithography, ink-jet printing, and dip-coating on micro-contact printed substrates, we form hierarchically organized silica structures that exhibit order and function on multiple scales: on the molecular scale, functional organic moieties are positioned on pore surfaces, on the mesoscale, mono-sized pores are organized into 1-, 2-, or 3-dimensional networks, providing size-selective accessibility from the gas or liquid phase, and on the macroscale, 2-dimensional arrays and fluidic or photonic systems may be defined. These rapid patterning techniques establish for the first time a link between computer-aided design and rapid processing of self-assembled nanostructures. C1 Univ New Mexico, NSF Ctr Microengineered Mat, Adv Mat Lab, Sandia Natl Labs, Albuquerque, NM 87131 USA. RP Univ New Mexico, NSF Ctr Microengineered Mat, Adv Mat Lab, Sandia Natl Labs, Albuquerque, NM 87131 USA. NR 25 TC 2 Z9 2 U1 0 U2 3 PU MATERIALS RESEARCH SOC PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-532-3 J9 MATER RES SOC SYMP P PY 2000 VL 624 BP 231 EP 240 PG 10 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA BR97N UT WOS:000168247700032 ER PT S AU Bell, N Dimos, D AF Bell, N Dimos, D BE Chrisey, DB Gamota, DR Helvajian, H Taylor, DP TI Calculation of Hamaker constants in nonaqueous fluid media SO MATERIALS DEVELOPMENT FOR DIRECT WRITE TECHNOLOGIES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials Development for Direct Write Technologies CY APR 24-26, 2000 CL SAN FRANCISCO, CA SP Mat Res Soc AB Calculations of the Hamaker constants representing the van der Waals interactions between conductor, resistor and dielectric materials are performed using Lifshitz theory. The calculation of the parameters for the Ninham-Parsegian relationship for several non-aqueous liquids has been derived based on literature dielectric data. Discussion of the role of van der Waals forces in the dispersion of particles is given for understanding paste formulation. Experimental measurements of viscosity are presented to show the role of dispersant truncation of attractive van der Waals forces. C1 Sandia Natl Labs, Ceram Mat Dept, Albuquerque, NM 87123 USA. RP Bell, N (reprint author), Sandia Natl Labs, Ceram Mat Dept, 1515 Eubank Blvd SE,MS 1411, Albuquerque, NM 87123 USA. NR 11 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 1-55899-532-3 J9 MATER RES SOC SYMP P PY 2000 VL 624 BP 275 EP 280 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA BR97N UT WOS:000168247700038 ER PT S AU Carlson, CM Rivkin, TV Parilla, PA Perkins, JD Ginley, DS Kozyrev, AB Oshadchy, VN Pavlov, AS Golovkov, A Sugak, M Kalinikos, D Sengupta, LC Chiu, L Zhang, X Zhu, Y Sengupta, S AF Carlson, CM Rivkin, TV Parilla, PA Perkins, JD Ginley, DS Kozyrev, AB Oshadchy, VN Pavlov, AS Golovkov, A Sugak, M Kalinikos, D Sengupta, LC Chiu, L Zhang, X Zhu, Y Sengupta, S BE Jia, QX Miranda, FA Oates, DE Xi, XX TI 30 GHz electronically steerable antennas using Ba(x)Sr(1-)xTiO(3)-based room-temperature phase shifters SO MATERIALS ISSUES FOR TUNABLE RF AND MICROWAVE DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials Issues for Tunable RF and Microwave Devices CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID FILMS AB We report the performance of 16-element phased array antennas operating at 30 GHz and ambient temperature. These antennas use BaxSr1-xTiO3(BST)-based phase shifters to produce the beam steering. Ferroelectric phase shifters offer advantages over current semiconductor and ferrite devices including faster switching speeds and lower costs. Also, ferroelectric phase shifters offer higher power handling capability than semiconductor devices and also have high radiation resistance. We made phase shifters from laser-ablated epitaxial BST films as well as from polycrystalline BST-oxide composite films. Although neither the devices nor the materials themselves are fully optimized, phase shifters have shown > 360 degrees of phase shift with < 350 V DC bias (E < 9 V/mu m) and similar to 8 dB insertion loss. With ferroelectric phase shifters incorporated, antennas show radiation patterns with central-lobe half-power widths of similar to 13 degrees and side lobe intensities down by more than 10 dB. Using the phase shifters, the central lobe can be shifted, or "steered," by +/-18 degrees in either direction. These results demonstrate a first step toward a prototype steerable antenna for 20-30 GHz satellite communications as well as other applications. C1 Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. St Petersburg Electrotech Univ, St Petersburg 197376, Russia. Paratek Microwave Inc, Columbia, MD 21045 USA. RP Carlson, CM (reprint author), Univ Colorado, Dept Phys, Boulder, CO 80309 USA. NR 7 TC 11 Z9 11 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-511-0 J9 MATER RES SOC SYMP P PY 2000 VL 603 BP 15 EP 25 PG 11 WC Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BQ82C UT WOS:000089705600002 ER PT S AU Findikoglu, AT Jia, QX Kwon, C Gibbons, BJ Rasmussen, KO Fan, Y Reagor, DW Bishop, AR AF Findikoglu, AT Jia, QX Kwon, C Gibbons, BJ Rasmussen, KO Fan, Y Reagor, DW Bishop, AR BE Jia, QX Miranda, FA Oates, DE Xi, XX TI Electrodynamic properties of single-crystal and thin-film strontium titanate, and thin-film barium strontium titanate SO MATERIALS ISSUES FOR TUNABLE RF AND MICROWAVE DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials Issues for Tunable RF and Microwave Devices CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID SRTIO3; TEMPERATURE AB We have used a coplanar waveguide structure to study broadband electrodynamic properties of single-crystal and thin-film strontium titanate (STO), and thin-film barium strontium titanate (BSTO). We have implemented low-frequency capacitance (100 Hz - 1 MHz), swept-frequency transmittance (45 MHz - 4 GHz), and time-domain transmittance (dc - several GHz) measurements to determine effective refractive index(or dielectric constant), and dissipation factor (or, loss tangent) as a function of de bias (up to 4x10(6) V/m) and temperature (20 - 300 K). The STO samples used superconducting electrodes and were designed to operate at cryogenic temperatures, whereas BSTO samples used normal conducting electrodes and exhibited optimal performance around room temperature. By using nearly identical electrode geometries for all devices, we were able to conduct a direct comparative study among them, and investigate not only single-crystal vs thin-film, but also cryogenic vs room-temperature applications. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Calif State Univ Long Beach, Dept Phys, Long Beach, CA 90840 USA. RP Findikoglu, AT (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Rasmussen, Kim/B-5464-2009; Jia, Q. X./C-5194-2008 OI Rasmussen, Kim/0000-0002-4029-4723; NR 13 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 1-55899-511-0 J9 MATER RES SOC SYMP P PY 2000 VL 603 BP 27 EP 36 PG 10 WC Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BQ82C UT WOS:000089705600003 ER PT S AU Gibbons, BJ Fan, Y Findikoglu, AT Reagor, DW Jia, QX AF Gibbons, BJ Fan, Y Findikoglu, AT Reagor, DW Jia, QX BE Jia, QX Miranda, FA Oates, DE Xi, XX TI Rf-magnetron sputtered strontium titanate: Structure, processing and property relationships SO MATERIALS ISSUES FOR TUNABLE RF AND MICROWAVE DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials Issues for Tunable RF and Microwave Devices CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID SRTIO3 THIN-FILMS; DIELECTRIC-PROPERTIES; CAPACITORS; TUNABILITY; GROWTH AB The low frequency dielectric properties of epitaxial SrTiO3 thin films deposited on LaAlO3 are presented. The films were deposited using radio-frequency magnetron sputtering from stoichiometric targets in an Ar/O-2 atmosphere. For the first time, the effects of in situ ozone annealing during the early stages of deposition were explored. X-ray diffraction results indicated that the ozone treatment resulted in more symmetric and sharper diffraction peaks (2 Theta-FWHM decreased from 0.17 degrees to 0.10 degrees). In addition, the peaks for the ozone treated samples were shifted in 20 towards values approaching the bulk value. Rutherford backscattering measurements showed Sr/Ti ratios of 1:1 for these samples, indicating these peak shifts are not due to compositional variations. The dielectric constant of the ozone treated samples increased from 275 at room temperature to 1175 at 22 K (measured at 100 kHz). The effective loss tangent of the device remained between 1 x 10(-4) and 1 x 10(-3) down to 100 K, where it began to increase. The tunability was also measured. The ozone treated sample showed tunability of 46%, 43% and 38% at 22 K, 40 K and 60 K, respectively. Finally, similar measurements were completed at 1 MHz, indicating a minimal dependence of these properties on frequencies in this range. C1 Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. RP Gibbons, BJ (reprint author), Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, POB 1663, Los Alamos, NM 87545 USA. RI Jia, Q. X./C-5194-2008 NR 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 1-55899-511-0 J9 MATER RES SOC SYMP P PY 2000 VL 603 BP 57 EP 62 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BQ82C UT WOS:000089705600006 ER PT S AU Im, J Auciello, O Streiffer, SK Baumann, PK Eastman, JA Kaufman, DY Krauss, AR Li, JX AF Im, J Auciello, O Streiffer, SK Baumann, PK Eastman, JA Kaufman, DY Krauss, AR Li, JX BE Jia, QX Miranda, FA Oates, DE Xi, XX TI Ba1-xSrxTiO3 thin film sputter-growth processes and electrical property relationships for high frequency devices SO MATERIALS ISSUES FOR TUNABLE RF AND MICROWAVE DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials Issues for Tunable RF and Microwave Devices CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc AB Precise control of Ba1-xSrxTiO3 (BST) film composition is critical for the production of high-quality BST thin films. Specifically, it is known that nonstoichiometry greatly affects the electrical properties of BST film capacitors. We are investigating the composition-microstructure-electrical property relationships of polycrystalline BST films produced by magnetron sputter-deposition using a single target with a Ba/Sr ratio of 50/50 and a (Ba+Sr)/Ti ratio of 1.0. It was determined that the (Ba+Sr)/Ti ratios of these BST films could be adjusted from 0.73 to 0.98 by changing the total (Ar+O-2) process pressure, while the O-2/Ar ratio did not strongly affect the metal ion composition. The crystalline quality as well as the measured dielectric constant, dielectric tunability, and electrical breakdown voltage of BST films have been found to be strongly dependent on the composition of the BST films, especially the (Ba+Sr)/Ti ratio. We discuss the impact of BST film composition control, through film deposition and process parameters, on the electrical properties of BST capacitors for high frequency devices. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem & Mat Sci, Argonne, IL 60439 USA. Johnson Matthey Elect, Spokane, WA 99216 USA. RP Im, J (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Streiffer, Stephen/A-1756-2009; Eastman, Jeffrey/E-4380-2011; OI Eastman, Jeff/0000-0002-0847-4265 NR 7 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 1-55899-511-0 J9 MATER RES SOC SYMP P PY 2000 VL 603 BP 63 EP 68 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BQ82C UT WOS:000089705600007 ER PT S AU Baumann, PK Kaufman, DY Streiffer, SK Im, J Auciello, O Erck, RA Giumarra, J Zebrowski, J Baldo, P McCormick, A AF Baumann, PK Kaufman, DY Streiffer, SK Im, J Auciello, O Erck, RA Giumarra, J Zebrowski, J Baldo, P McCormick, A BE Jia, QX Miranda, FA Oates, DE Xi, XX TI MOCVD growth and characterization of (BaxSr1-x)Ti1+yO3+z thin films for high frequency devices SO MATERIALS ISSUES FOR TUNABLE RF AND MICROWAVE DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials Issues for Tunable RF and Microwave Devices CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID CHEMICAL-VAPOR-DEPOSITION; DIELECTRIC-PROPERTIES AB We have investigated the structural and electrical characteristics of (Bs(x)Sr(1-x))Ti1+yO3+z (BST) thin films. The BST thin films were deposited at 650 degrees C on platinized silicon with good thickness and composition uniformity using a large area, vertical liquid-delivery metalorganic chemical vapor deposition (MOCVD) system. The (Ba+Sr)/Ti ratio of the BST films was varied from 0.96 to 1.05 at a fixed Ba/Sr ratio of 70/30, as determined using x-ray fluorescence spectroscopy (XRF) and Rutherford backscattering spectrometry (RBS). Patterned Pt top electrodes were deposited onto the BST films at 350 degrees C through a shadow mask using electron beam evaporation. Annealing the entire capacitor structure in air at 700 degrees C after deposition of top electrodes resulted in a substantial reduction of the dielectric loss. Useful dielectric tunability as high as 2.3:1 was measured. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Baumann, PK (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Streiffer, Stephen/A-1756-2009 NR 11 TC 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 1-55899-511-0 J9 MATER RES SOC SYMP P PY 2000 VL 603 BP 169 EP 174 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BQ82C UT WOS:000089705600022 ER PT S AU Gim, Y Hudson, T Fan, Y Findikoglu, AT Kwon, C Gibbons, BJ Jia, QX AF Gim, Y Hudson, T Fan, Y Findikoglu, AT Kwon, C Gibbons, BJ Jia, QX BE Jia, QX Miranda, FA Oates, DE Xi, XX TI Dielectric properties of Ba1-xSxTiO3 films grown on LaAlO3 substrates SO MATERIALS ISSUES FOR TUNABLE RF AND MICROWAVE DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials Issues for Tunable RF and Microwave Devices CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID THIN-FILMS; DEVICES AB We report the crystal structures and dielectric properties of barium strontium titanate, Ba1-xSrxTiO3 (BST), films deposited on LaAlO3 substrates using pulsed laser deposition, where x 0.1 to 0.9 at an interval of 0.1. We have found that when x < 0.4 the c-axis is parallel to the plane of the substrate but normal as x approaches 1. Temperature-dependent capacitance measurements at 1 MHz show that the capacitance has a peak and that the peak temperature decreases with increasing x. We have found that the peak temperatures of the films are about 70 degrees C higher than those of bulk BSTs when x < 0.4. From room-temperature capacitance (C) vs applied voltage (V) measurements, we have found that the C-V curves of the BST films exhibit hysteresis except for x = 0.9 and that the peak voltage at which the capacitance becomes maximum decreases with increasing x. At room temperature, the Ba0.6Sr0.4TiO3 tunability (approximate to 37%) with an applied electricfield of 40 kV/cm. C1 Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. RP Gim, Y (reprint author), Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, MS-K763, Los Alamos, NM 87545 USA. RI Jia, Q. X./C-5194-2008 NR 9 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 1-55899-511-0 J9 MATER RES SOC SYMP P PY 2000 VL 603 BP 175 EP 180 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BQ82C UT WOS:000089705600023 ER PT S AU Gong, XY Liu, J Samuels, WD AF Gong, XY Liu, J Samuels, WD BE WunFogle, M Uchino, K Ito, Y Gotthardt, R TI Molecular recognition of organic compounds by imprinted silica SO MATERIALS OF SMART SYSTEMS III SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT 3rd Symposium on Smart Materials held at the 1999 MRS Fall Meeting CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP USN Off Res, Mat Res Soc ID NETWORK POLYMERS; SITES AB Specific interactions between silica and organic molecules play an important role in molecular imprinting, molecular recognition, and enzyme activity. To understand the specific interactions, six pairs of organic compounds were chosen and investigated for their molecular imprinting capabilities on silica. Silica adsorbents imprinted by methyl red or p-methyl red, methyl orange or ethyl orange, and histidine-alanine or histidine-leucine can recognize their imprinting molecules. Silica samples "imprinted" with methyl red or ethyl red, 4,9-diaminoflourenone or 3,3'-diaminodiphenylmethane, and I-histidine or d,E-histidine do not recognize their "imprinting" molecules. The molecular recognition is related to the structure of the imprinting molecules. The following lessons were learnt: I) Three or more strong interaction sites on the imprinting molecules are necessary to endow silica with recognition capability; 2) Position of functional groups is more important than their size to achieve the molecular recognition; 3) Chiral recognition needs stronger interaction and/or more interaction sites. C1 Pacific NW Natl Labs, Richland, WA 99352 USA. RP Gong, XY (reprint author), Pacific NW Natl Labs, Battelle Blvd, Richland, WA 99352 USA. NR 13 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 1-55899-512-9 J9 MATER RES SOC SYMP P PY 2000 VL 604 BP 311 EP 316 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BQ82D UT WOS:000089705900045 ER PT S AU LaVan, DA Buchheit, TE AF LaVan, DA Buchheit, TE BE DeBoer, MP Heuer, AH Jacobs, SJ Peeters, E TI Testing of critical features of polysilicon MEMS SO MATERIALS SCIENCE OF MICROELECTROMECHANICAL SYSTEMS (MEMS) DEVICES II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium MM on Materials Science of Microelectromechanical Systems (MEMS) Devices II held at the 1999 MRS Fall Meeting CY NOV 29-DEC 01, 1999 CL BOSTON, MA SP Mat Res Soc ID TENSILE AB The behavior of MEMS devices is limited by the strength of critical features such as thin ligaments, oxide cuts joining layers, pin joints and hinges. Devices fabricated at Sandia's Microelectronic Development Laboratory have been successfully tested to investigate these features. A series of measurements were performed on samples with gage lengths of 15 to 1000 microns, using conventional and tungsten coated samples as well as samples that include the critical features of standard components in the test section. Specimens have a freely moving pin joint on one end that anchors the sample to the silicon die to allow rotation to reduce effects of bending. Each sample is loaded in uniaxial tension by pulling laterally with a flat tipped diamond in a computer-controlled Nanoindenter. Load is calculated by resolving the measured lateral and normal forces into the applied tensile force and frictional losses. The specimen cross section and gage length dimensions were verified by measuring against a standard in the SEM. Multiple tests can be programmed at one time and performed without operator assistance allowing the collection of significant populations of data. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP LaVan, DA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI LaVan, David/C-3943-2012 OI LaVan, David/0000-0002-1952-0028 NR 16 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 1-55899-513-7 J9 MATER RES SOC SYMP P PY 2000 VL 605 BP 19 EP 24 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BR05E UT WOS:000165506600003 ER PT S AU Habermehl, S Glenzinski, AK Halliburton, WM Sniegowski, JJ AF Habermehl, S Glenzinski, AK Halliburton, WM Sniegowski, JJ BE DeBoer, MP Heuer, AH Jacobs, SJ Peeters, E TI Properties of low residual stress silicon oxynitrides used as a sacrificial layer SO MATERIALS SCIENCE OF MICROELECTROMECHANICAL SYSTEMS (MEMS) DEVICES II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium MM on Materials Science of Microelectromechanical Systems (MEMS) Devices II held at the 1999 MRS Fall Meeting CY NOV 29-DEC 01, 1999 CL BOSTON, MA SP Mat Res Soc ID FILMS; NITRIDE AB Low residual stress silicon oxynitride thin films are investigated for use as a replacement for silicon dioxide (SiO2) as sacrificial layer in surface micromachined microelectrical-mechanical systems (MEMS). It is observed that the level of residual stress in oxynitrides is a function of the nitrogen content in the film. MEMS film stacks are prepared using both SiO2 and oxynitride sacrificial layers. Wafer bow measurements indicate that wafers processed with oxynitride release layers are significantly flatter. Polycrystalline Si (poly-Si) cantilevers fabricated under the same conditions are observed to be flatter when processed with oxynitride rather than SiO2 sacrificial layers. These results are attributed to the lower post-processing residual stress of oxynitride compared to SiO2. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Habermehl, S (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 13 TC 5 Z9 5 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-513-7 J9 MATER RES SOC SYMP P PY 2000 VL 605 BP 49 EP 54 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BR05E UT WOS:000165506600008 ER PT S AU Auciello, O Krauss, AR Gruen, DM Meyer, EM Busmann, HG Tucek, J Sumant, A Jayatissa, A Moldovan, N Mancini, DC Gardos, MN AF Auciello, O Krauss, AR Gruen, DM Meyer, EM Busmann, HG Tucek, J Sumant, A Jayatissa, A Moldovan, N Mancini, DC Gardos, MN BE DeBoer, MP Heuer, AH Jacobs, SJ Peeters, E TI Two- and three-dimensional ultrananocrystalline diamond (UNCD) structures for a high resolution diamond-based MEMS technology SO MATERIALS SCIENCE OF MICROELECTROMECHANICAL SYSTEMS (MEMS) DEVICES II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium MM on Materials Science of Microelectromechanical Systems (MEMS) Devices II held at the 1999 MRS Fall Meeting CY NOV 29-DEC 01, 1999 CL BOSTON, MA SP Mat Res Soc DE ultrananocrystalline diamond films; high resolution; MEMS technology ID MICROWAVE PLASMAS; CARBON DIMER; FILM GROWTH; THIN-FILMS; SENSOR AB Silicon is currently the most commonly used material for the fabrication of microelectromechanical systems (MEMS). However, silicon-based MEMS will not be suitable for long-endurance devices involving components rotating at high speed, where friction and wear need to be minimized, components such as 2-D cantilevers that may be subjected to very large flexural displacements, where stiction is a problem, or components that will be exposed to corrosive environments. The mechanical, thermal, chemical, and tribological properties of diamond make it an ideal material for the fabrication of long-endurance MEMS components. Cost-effective fabrication of these components could in principle be achieved by coating Si with diamond films and using conventional lithographic patterning methods in conjunction with e. g. sacrificial Ti or SiO2 layers. However, diamond coatings grown by conventional chemical vapor deposition (CVD) methods exhibit a coarse-grained structure that prevents high-resolution patterning, or a fine-grained microstructure with a significant amount of intergranular non-diamond carbon. We demonstrate here the fabrication of 2-D and 3-D phase-pure ultrananocrystalline diamond (UNCD) MEMS components by coating Si with UNCD films, coupled with lithographic patterning methods involving sacrificial release layers. UNCD films are grown by microwave plasma CVD using C-60-Ar or CH4-Ar gas mixtures, which result in films that have 3-5 nm grain size, are 10-20 times smoother than conventionally grown diamond films, are extremely resistant to corrosive environments, and are predicted to have a brittle fracture strength similar to that of single crystal diamond. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Auciello, O (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 30 TC 8 Z9 8 U1 1 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-513-7 J9 MATER RES SOC SYMP P PY 2000 VL 605 BP 73 EP 78 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BR05E UT WOS:000165506600010 ER PT S AU Mani, SS Fleming, JG Sniegowski, JJ de Boer, MP Irwin, LW Walraven, JA Tanner, DM La Van, DA AF Mani, SS Fleming, JG Sniegowski, JJ de Boer, MP Irwin, LW Walraven, JA Tanner, DM La Van, DA BE DeBoer, MP Heuer, AH Jacobs, SJ Peeters, E TI Selective W for coating and releasing MEMS devices SO MATERIALS SCIENCE OF MICROELECTROMECHANICAL SYSTEMS (MEMS) DEVICES II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium MM on Materials Science of Microelectromechanical Systems (MEMS) Devices II held at the 1999 MRS Fall Meeting CY NOV 29-DEC 01, 1999 CL BOSTON, MA SP Mat Res Soc ID SURFACE MICROMACHINED MICROENGINE; TUNGSTEN; FILMS AB Two major problems associated with Si-based MEMS (MicroElectroMechanical Systems) devices are stiction and wear. Surface modifications are needed to reduce both adhesion and friction in micromechanical structures to solve these problems. In this paper, we will present a CVD (Chemical Vapor Deposition) process that selectively coats MEMS devices with tungsten and significantly enhances device durability. Tungsten CVD is used in the integrated-circuit industry, which makes this approach manufacturable. This selective deposition process results in a very conformal coating and can potentially address both stiction and wear problems confronting MEMS processing. The selective deposition of tungsten is accomplished through the silicon reduction of WF6. The self-limiting nature of this selective W deposition process ensures the consistency necessary for process control. The tungsten is deposited after the removal of the sacrificial oxides to minimize stress and process integration problems. Tungsten coating adheres well and is hard and conducting, requirements for device performance. Furthermore, since the deposited tungsten infiltrates under adhered silicon parts and the volume of W deposited is less than the amount of Si consumed, it appears to be possible to release stuck parts that are contacted over small areas such as dimples. The wear resistance of selectively coated W parts has been shown to be significantly improved on microengine test structures. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Mani, SS (reprint author), Sandia Natl Labs, MS 1084,POB 5800, Albuquerque, NM 87185 USA. NR 19 TC 10 Z9 11 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-513-7 J9 MATER RES SOC SYMP P PY 2000 VL 605 BP 135 EP 140 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BR05E UT WOS:000165506600019 ER PT S AU Coutts, TJ Young, DL Li, XN AF Coutts, TJ Young, DL Li, XN BE Ginley, DS Perkins, JD Kawazoe, H Newns, DM Kozyrev, AB TI Fundamental advances in transparent conducting oxides SO MATERIALS SCIENCE OF NOVEL OXIDE-BASED ELECTRONICS SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on Materials Science of Novel Oxide-Based Electronics held at the 2000 MRS Spring Meeting CY APR 24-27, 2000 CL SAN FRANCISCO, CA SP Mat Res Soc ID THIN-FILMS AB Increasingly large-volume markets for large-area, flat-panel displays and photovoltaic panels are likely to be established in the early years of the next century and transparent conducting oxides (TCOs) of improved opto-electronic properties will be required to enable some of these applications to be realized. Our work is focusing on improving both the fabrication-limited properties of the materials (extrinsic), and materials-limited properties (intrinsic). The emphasis on achieving improved electrical and optical properties hinges on achieving higher electron mobility via intrinsic and/or extrinsic properties. To this end, we have investigated the properties of several TCOs including cadmium oxide, tin oxide, zinc oxide, cadmium stannate and zinc stannate. These may be deposited by chemical vapor deposition (CVD) or sputtering and we hope to establish the capability to fabricate compounds and alloys in the cadmium oxide, tin oxide, zinc oxide ternary phase diagram. The properties of the materials have been investigated using a wide variety of techniques including high-resolution electron microscopy, atomic force microscopy and X-ray diffraction, as well as Mossbauer, Raman and UV/visible/NIR spectroscopies. We have measured the transport properties (conductivity, Hall, Seebeck and Nernst coefficients) and have obtained the effective mass, relaxation time, Fermi energy, and scattering parameter. This information has been obtained as a function of carrier concentration, which depends on the deposition and annealing procedures. We have found that the mobilities of free-electrons in the cadmium-bearing compounds are greatly superior to those in the other materials, because they have much longer electron relaxation times. In the case of cadmium oxide, there is also great benefit from a much lower effective mass. We are gaining a clearer understanding of the fundamental microscopic attributes needed for TCOs, which will be required in more-demanding, and rapidly emerging, applications. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 14 TC 8 Z9 8 U1 0 U2 2 PU MATERIALS RESEARCH SOC PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-531-5 J9 MATER RES SOC SYMP P PY 2000 VL 623 BP 199 EP 209 PG 11 WC Materials Science, Coatings & Films; Physics, Condensed Matter SC Materials Science; Physics GA BS03D UT WOS:000168381900028 ER PT S AU Young, DL Coutts, TJ Li, X Keane, J Kaydanov, VI Gilmore, AS AF Young, DL Coutts, TJ Li, X Keane, J Kaydanov, VI Gilmore, AS BE Ginley, DS Perkins, JD Kawazoe, H Newns, DM Kozyrev, AB TI Density-of-states effective mass and scattering parameter measurements on transparent conducting oxides using second-order transport phenomena SO MATERIALS SCIENCE OF NOVEL OXIDE-BASED ELECTRONICS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials Science of Novel Oxide-Based Electronics held at the 2000 MRS Spring Meeting CY APR 24-27, 2000 CL SAN FRANCISCO, CA SP Mat Res Soc ID FILMS; BAND AB Transparent conducting oxides (TCO) have relatively low mobilities, which limit their performance optically and electrically, and which limit the techniques that may be used to explore their band structure via the effective mass. We have used transport theory to directly measure the density-of-states effective mass and other fundamental electronic properties of TCO films. The Boltzmann transport equation may be solved to give analytic solutions to the resistivity, Hall, Seebeck, and Nernst coefficients. In rum, these may be solved simultaneously to give the density-of-states effective mass, the Fermi energy relative to either the conduction or valence band, and a scattering parameter, s, which characterizes the relaxation time dependence on the carrier energy and can serve as a signature of the dominate scattering mechanism. The little-known Nernst effect is essential for determining the scattering parameter and, thereby, the effective scattering mechanism(s). We constructed equipment to measure these four transport coefficients on the same sample over a temperature range of 30 - 350 K for thin films deposited on insulating substrates. We measured the resistivity, Hall, Seebeck, and Nernst coefficients for rf magnetron-sputtered aluminum-doped zinc oxide. We found that the effective mass for zinc oxide increases from a minimum value of 0.24m(c) up to a value of 0.47m(c) at a carrier density of 4.5 x 10(20) cm(-3), indicating a nonparabolic conduction energy band. In addition, our measured density-of-states effective values are nearly equal to conductivity effective mass values estimated from the plasma frequency, denoting a single energy minimum with a nearly spherical, constant-energy surface. The measured scattering parameter, mobility vs. temperature, along with Seebeck coefficient values, characterize ionized impurity scattering in the ZnO:Al and neutral impurity scattering in the undoped material. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Young, DL (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 19 TC 0 Z9 0 U1 0 U2 8 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-531-5 J9 MATER RES SOC SYMP P PY 2000 VL 623 BP 259 EP 264 PG 6 WC Materials Science, Coatings & Films; Physics, Condensed Matter SC Materials Science; Physics GA BS03D UT WOS:000168381900034 ER PT S AU Stauber, RE Parilla, PA Perkins, JD Ginley, DS AF Stauber, RE Parilla, PA Perkins, JD Ginley, DS BE Ginley, DS Perkins, JD Kawazoe, H Newns, DM Kozyrev, AB TI Growth and chemical substitution of transparent p-type CuAlO2 SO MATERIALS SCIENCE OF NOVEL OXIDE-BASED ELECTRONICS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials Science of Novel Oxide-Based Electronics held at the 2000 MRS Spring Meeting CY APR 24-27, 2000 CL SAN FRANCISCO, CA SP Mat Res Soc ID ELECTRICAL-CONDUCTION; THIN-FILMS AB CuAlO2 is one of several materials currently being investigated for application as a p-type transparent conducting oxide. In this paper we report a method of making c-axis oriented CuAlO2 thin films which eliminates previously reported phase-purity and surface morphology problems. Thin film precursors of CuAlO2 were deposited on YSZ (100) substrates by room-temperature radio frequency sputtering. Subsequent annealing in 10mT of oxygen at temperatures as low as 800 degrees C resulted in phase-pure, textured CuAlO2. The films were p-type and transparent with a gap of 3.5eV, but typical carrier concentrations were low (on the order of 10(16) cm(-3)). Oxygen anneals at 700 degrees C in 1 atm of O-2 raised this to 10(18) cm(-3) in some samples. In order to increase the carrier concentration further, we are testing chemical substitution on the metal sublattice. Initial experiments were done with Mg as a dopant, either by direct solid-state synthesis for bulk materials or by alternating deposition of MgO and CuAlO2 during the pulsed laser deposition of thin films. At Mg molar concentrations of 1% or less, the bulk material was phase-pure CuAlO2 by x-ray diffraction, but was mixed-phase CuAl2O4 and CuO when the Mg concentration was increased to 2%. Thin films sputtered from the 1% Mg substituted target crystallized to CuAlO2 after a 940 degrees C anneal at 10T O-2, but were more than 30 times more resistive than the undoped films. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Stauber, RE (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 4 TC 8 Z9 8 U1 0 U2 5 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-531-5 J9 MATER RES SOC SYMP P PY 2000 VL 623 BP 265 EP 270 PG 6 WC Materials Science, Coatings & Films; Physics, Condensed Matter SC Materials Science; Physics GA BS03D UT WOS:000168381900035 ER PT S AU Ferrer, JC Liliental-Weber, Z Reese, H Chiu, YJ Hu, E AF Ferrer, JC Liliental-Weber, Z Reese, H Chiu, YJ Hu, E BE Ginley, DS Perkins, JD Kawazoe, H Newns, DM Kozyrev, AB TI Influence of low temperature-grown GaAs on lateral thermal oxidation of Al0.98Ga0.02As SO MATERIALS SCIENCE OF NOVEL OXIDE-BASED ELECTRONICS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials Science of Novel Oxide-Based Electronics held at the 2000 MRS Spring Meeting CY APR 24-27, 2000 CL SAN FRANCISCO, CA SP Mat Res Soc ID WET OXIDATION; ALGAAS AB The lateral thermal oxidation process of Al0.98Ga0.02As layers has been studied by transmission electron microscopy. Growing a low-temperature GaAs layer below the Al0.98Ga0.02As has been shown to result in better quality of the oxide/GaAs interfaces compared to reference samples. While the later have As precipitation above and below the oxide layer and roughness and voids at the oxide/GaAs interface, the structures with low-temperature have less As precipitation and develop interfaces without voids. These results are explained in terms of the diffusion of the As toward the low temperature layer. The effect of the addition of a SiO2 cap layer is also discussed. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Ferrer, JC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 7 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-531-5 J9 MATER RES SOC SYMP P PY 2000 VL 623 BP 407 EP 410 PG 4 WC Materials Science, Coatings & Films; Physics, Condensed Matter SC Materials Science; Physics GA BS03D UT WOS:000168381900056 ER PT J AU Drumm, CR Lorenz, J AF Drumm, CR Lorenz, J TI Parallel FE approximation of the even/odd-parity form of the linear Boltzmann equation SO MATHEMATICAL AND COMPUTER MODELLING LA English DT Article DE radiation transport; Boltzmann equation; even/odd parity; conjugate gradient method; parallel computing ID ELECTRON-PHOTON TRANSPORT AB A novel solution method has been developed to solve the linear Boltzmann equation on an unstructured triangular mesh. Instead of tackling the first-order form of the equation, this approach is based on the even/odd-parity form in conjunction with the conventional multigroup discrete-ordinates approximation. The finite element method is used to treat the spatial dependence. The solution method is unique in that the space-direction dependence is solved simultaneously, eliminating the need for the conventional inner iterations, and the method is well suited for massively parallel computers. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Radiat & Electromagnet Anal Dept, Albuquerque, NM 87185 USA. Univ New Mexico, Dept Math & Stat, Albuquerque, NM 87131 USA. RP Drumm, CR (reprint author), Sandia Natl Labs, Radiat & Electromagnet Anal Dept, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0895-7177 J9 MATH COMPUT MODEL JI Math. Comput. Model. PD JAN-FEB PY 2000 VL 31 IS 2-3 BP 55 EP 71 DI 10.1016/S0895-7177(99)00223-X PG 17 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA 287PL UT WOS:000085514700005 ER PT B AU Harvey, NR Marshall, S AF Harvey, NR Marshall, S BE Goutsias, J Vincent, L Bloomberg, DS TI GA optimisation of multidimensional grey-scale soft morphological filters with applications in archive film restoration SO MATHEMATICAL MORPHOLOGY AND ITS APPLICATIONS TO IMAGE AND SIGNAL PROCESSING SE Computational Imaging and Vision LA English DT Proceedings Paper CT 5th International Symposium on Mathematical Morphology (ISMM) CY JUN 26-29, 2000 CL XEROX PALO ALTO RES CTR, PALO ALTO, CA SP Xerox Corp HO XEROX PALO ALTO RES CTR DE soft morphology; genetic algorithms; film dirt; archive restoration AB A technique using Genetic Algorithms (GAs) for the optimisation of multidimensional grey-scale soft morphological filters is described, which has applications in archive film restoration. It applies specifically to the problem of film-dirt removal in archive film sequences. Because of. ageing scratches and film dirt, much valuable film archive material is unusable. There is therefore a demand for automatic techniques which can remove these Aim artifacts whilst preserving image structure, fine detail and without introducing motion blur. The optimisation criterion is based on mean absolute error (MAE). The optimisation is undertaken using genetic algorithms. An artificial training set is constructed from within the archive material by selecting relatively ly clean areas and transferring examples of noise and dirt to these frames. Examples of applying the techniques described to a real film sequence, provided by the British Broadcasting Corporation (BBC), are shown. C1 Los Alamos Natl Lab, Nonproliferat & Int Secur Div, Space & Remote Sensing Sci Grp, Los Alamos, NM 87544 USA. RP Harvey, NR (reprint author), Los Alamos Natl Lab, Nonproliferat & Int Secur Div, Space & Remote Sensing Sci Grp, POB 1663, Los Alamos, NM 87544 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU KLUWER ACADEMIC PUBLISHERS PI NORWELL PA 101 PHILIP DRIVE, ASSINIPPI PARK, NORWELL, MA 02061 USA BN 0-7923-7862-8 J9 COMPUT IMAGING VIS PY 2000 VL 18 BP 129 EP 138 PG 10 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Mathematics, Applied SC Automation & Control Systems; Computer Science; Engineering; Mathematics GA BR53R UT WOS:000166729300014 ER PT S AU Lara-Curzio, E AF Lara-Curzio, E BE Jenkins, MG LaraCurzio, E Gonczy, ST TI Stress-rupture, overstrerssing, and a new methodology to assess the high-temperature durability and reliability of CFCCs SO MECHANICAL, THERMAL AND ENVIRONMENTAL TESTING AND PERFORMANCE OF CERAMIC COMPOSITES AND COMPONENTS SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Environmental, Mechanical, and Thermal Properties and Performance of Continuous Fiber Ceramic Composite (CFCC) Materials and Components CY MAY 18, 1999 CL SEATTLE, WA SP Amer Soc Testing & Mat, Comm E08 Fatigue & Fracture, Amer Soc Testing & Mat, Comm D30 Adv Composites DE ceramic-matrix composites; durability; reliability; high temperature; stress-rupture; overstressing; testing ID MATRIX COMPOSITES; FIBER AB A testing methodology is proposed to assess the durability and reliability of non-oxide continuous fiber-reinforced ceramic composites for high temperature applications. The strategy is based on determining the reliability of these materials when subjected to random loading schedules consisting of mechanical load and temperature spikes that are superimposed upon otherwise constant stress and temperature values. The frequency and magnitude of the mechanical load and temperature spikes would be representative of the number and characteristics of the transients that are associated with a particular industrial application and that are expected to occur over the life of the component. The effect of overstressing on the stress-rupture behavior of a ceramic grade (CG) Nicalon(TM) fiber-reinforced silicon carbide (SiC) matrix composite was investigated and results are presented from tests conducted in ambient air at 950 degreesC. C1 Oak Ridge Natl Lab, Mech Characterizat & Anal Grp, Oak Ridge, TN 37831 USA. RP Lara-Curzio, E (reprint author), Oak Ridge Natl Lab, Mech Characterizat & Anal Grp, POB 2008, Oak Ridge, TN 37831 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 0-8031-2872-X J9 AM SOC TEST MATER PY 2000 VL 1392 BP 107 EP 117 DI 10.1520/STP15008S PG 11 WC Materials Science, Ceramics; Materials Science, Characterization & Testing SC Materials Science GA BR55G UT WOS:000166791500007 ER PT S AU Ferber, MK Lin, HT Keiser, J AF Ferber, MK Lin, HT Keiser, J BE Jenkins, MG LaraCurzio, E Gonczy, ST TI Oxidation behavior of non-oxide ceramics in a high-pressure, high-temperature steam environment SO MECHANICAL, THERMAL AND ENVIRONMENTAL TESTING AND PERFORMANCE OF CERAMIC COMPOSITES AND COMPONENTS SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Environmental, Mechanical, and Thermal Properties and Performance of Continuous Fiber Ceramic Composite (CFCC) Materials and Components CY MAY 18, 1999 CL SEATTLE, WA SP Amer Soc Testing & Mat, Comm E08 Fatigue & Fracture, Amer Soc Testing & Mat, Comm D30 Adv Composites DE silicon carbide; silicon nitride; ceramic; composite; CFCC; paralinear oxidation; microstructural analysis ID SILICON-CARBIDE; WATER-VAPOR AB This paper provides a review of two recent studies undertaken to examine the oxidation behavior of monolithic SiC and SiC-SiC composites in simulated and actual gas turbine environments. In the first study, a high-pressure and high-temperature test facility was used to expose a variety of structural ceramics and ceramic matrix composites to 15% water vapor carried in an air environment at 10 atm of total pressure and 1204 degreesC. The second study involved the exposure of a SiC-SiC combustor liner in an industrial gas turbine for approximately 2300 h at a total pressure of 10 atm and peak liner temperature of 1150 degreesC. In the two studies microstructural analyses were used to measure the rates of both silica scale formation and SiC recession. These experimentally determined rates were then compared with values predicted from established oxidadon/volatilization models. The estimates of the temperature and pressure sensitivities of the oxidation and volatilization rate constants, required for this comparison, were obtained from the literature. For the case of the combustor liner, the recession rate of SiC was well described by the model. However, the predicted rates of scale formation in both studies were significantly lower that the corresponding experimental values. Possible reasons for this discrepancy are addressed. C1 Oak Ridge Natl Lab, Res Staff, Oak Ridge, TN 37831 USA. RP Ferber, MK (reprint author), Oak Ridge Natl Lab, Res Staff, POB 2008,MS 6069, Oak Ridge, TN 37831 USA. NR 11 TC 3 Z9 3 U1 2 U2 3 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 0-8031-2872-X J9 AM SOC TEST MATER PY 2000 VL 1392 BP 201 EP 215 DI 10.1520/STP15015S PG 15 WC Materials Science, Ceramics; Materials Science, Characterization & Testing SC Materials Science GA BR55G UT WOS:000166791500014 ER PT S AU Lara-Curzio, E Singh, M AF Lara-Curzio, E Singh, M BE Jenkins, MG LaraCurzio, E Gonczy, ST TI The time-dependent deformation of carbon fiber-reinforced melt-infiltrated silicon carbide ceramic matrix composites: Stress-rupture and stress-relaxation behavior in air at 1000 degrees C SO MECHANICAL, THERMAL AND ENVIRONMENTAL TESTING AND PERFORMANCE OF CERAMIC COMPOSITES AND COMPONENTS SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Environmental, Mechanical, and Thermal Properties and Performance of Continuous Fiber Ceramic Composite (CFCC) Materials and Components CY MAY 18, 1999 CL SEATTLE, WA SP Amer Soc Testing & Mat, Comm E08 Fatigue & Fracture, Amer Soc Testing & Mat, Comm D30 Adv Composites DE ceramic-matrix composites; stress-rupture; stress-relaxation; oxidation; thermal expansion; melt infiltration; silicon carbide; carbon ID WOVEN C/SIC COMPOSITES; OXIDATION AB The stress-rupture and stress-relaxation behavior of carbon fiber-reinforced melt-infiltrated silicon carbide composites was investigated in ambient air at 1000 degreesC. It was found that the compliance of the material increases continuously with time when subjected either to a constant composite stress or strain in air at 1000 degreesC. The changes in compliance are explained based on the oxidation of the fiber coating, and on the oxidation, loss of cross-sectional area and rupture: of the reinforcing fibers. In the case of stress-rupture, the load previously carried by failed fibers is redistributed to their surviving neighboring fibers inducing further fiber failure. During stress-relaxation, fiber failure is reflected directly on the reduction of the load carried by the composite. By monitoring the expansion of the specimens during heating, prior to the application of the stress or strain, it was possible to determine the liner coefficients of thermal expansion of the material between 200 degreesC and 1000 degreesC. C1 Oak Ridge Natl Lab, Mech Characterizat & Anal Grp, Oak Ridge, TN 37831 USA. RP Lara-Curzio, E (reprint author), Oak Ridge Natl Lab, Mech Characterizat & Anal Grp, POB 2008, Oak Ridge, TN 37831 USA. NR 10 TC 1 Z9 1 U1 1 U2 3 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 0-8031-2872-X J9 AM SOC TEST MATER PY 2000 VL 1392 BP 216 EP 228 DI 10.1520/STP15016S PG 13 WC Materials Science, Ceramics; Materials Science, Characterization & Testing SC Materials Science GA BR55G UT WOS:000166791500015 ER PT S AU Lewinsohn, CA Henager, CH Simonen, EP Windisch, CF Jones, RH AF Lewinsohn, CA Henager, CH Simonen, EP Windisch, CF Jones, RH BE Jenkins, MG LaraCurzio, E Gonczy, ST TI The relationship between interphase oxidation and time-dependent failure in SiCf/SiCm composites SO MECHANICAL, THERMAL AND ENVIRONMENTAL TESTING AND PERFORMANCE OF CERAMIC COMPOSITES AND COMPONENTS SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Environmental, Mechanical, and Thermal Properties and Performance of Continuous Fiber Ceramic Composite (CFCC) Materials and Components CY MAY 18, 1999 CL SEATTLE, WA SP Amer Soc Testing & Mat, Comm E08 Fatigue & Fracture, Amer Soc Testing & Mat, Comm D30 Adv Composites DE silicon carbide; crack growth; interface oxidation; environmental susceptibility ID CERAMIC-MATRIX COMPOSITES; SUBCRITICAL CRACK-GROWTH; CONTINUOUS-FIBER; STRESS-RUPTURE; INTERMEDIATE TEMPERATURES; SILICON-CARBIDE; EMBRITTLEMENT; MECHANICS; AIR AB Flaw-tolerant ceramic matrix composites typically possess an interphase between the reinforcing fibers and the matrix that allows debonding for desirable mechanical properties. However, commonly used interphase materials, such as carbon and boron nitride, are susceptible to oxidation at elevated temperatures. In general, oxidation of interphase materials produces gases and voids between the fibers and the matrix leading to an increase in the compliance of bridging fibers and a subsequent decrease in the toughening increment due to fiber bridging. On the other hand, silicon carbide fibers and matrices oxidize to form solid reaction products (oxides), leading to increased bonding between fibers and the matrix. A competition between interphase oxidation and the formation of solid oxide phases determines the composite failure mechanism under a given set of environmental conditions. The mechanisms by which oxidation degrade the mechanical properties of SiCf/SiCm will be discussed. Techniques for identifying failure mechanisms and approaches to modeling component lifetimes will be presented. C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Lewinsohn, CA (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, POB 999, Richland, WA 99352 USA. NR 19 TC 1 Z9 1 U1 0 U2 2 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 0-8031-2872-X J9 AM SOC TEST MATER PY 2000 VL 1392 BP 229 EP 241 DI 10.1520/STP15017S PG 13 WC Materials Science, Ceramics; Materials Science, Characterization & Testing SC Materials Science GA BR55G UT WOS:000166791500016 ER PT S AU Unal, O AF Unal, O BE Jenkins, MG LaraCurzio, E Gonczy, ST TI Effect of loading mode on high-temperature tensile deformation of a SiC/SiC composite SO MECHANICAL, THERMAL AND ENVIRONMENTAL TESTING AND PERFORMANCE OF CERAMIC COMPOSITES AND COMPONENTS SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Environmental, Mechanical, and Thermal Properties and Performance of Continuous Fiber Ceramic Composite (CFCC) Materials and Components CY MAY 18, 1999 CL SEATTLE, WA SP Amer Soc Testing & Mat, Comm E08 Fatigue & Fracture, Amer Soc Testing & Mat, Comm D30 Adv Composites DE silicon carbide composite; tensile; creep; fatigue and high temperature ID CERAMIC-MATRIX COMPOSITES; FATIGUE; FIBER; FREQUENCY; BEHAVIOR AB Tensile deformation of a silicon carbide (SiC) matrix/Nicalon SiC fiber composite was studied under static and cyclic loads at 1300 degreesC in nitrogen environment. Monotonic tensile tests were carried out to determine the stress levels to be applied during the ensuing tests. It was :shown that under comparable stresses, higher strain accumulates under the static loads than the cyclic loads. Yet, the failure took place much more readily under the cyclic loads because of the damages induced on the load carrying Oo-fibers. When the applied cyclic loads were small, the total strain and the rate of strain accumulation were similar under both types of loading, indicating similar deformation mechanisms in this range. At higher loads, however, under the cyclic loading, the matrix and fiber cracking controlled the deformation; under the static loading, the fiber creep dominated the deformation. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Unal, O (reprint author), Iowa State Univ Sci & Technol, Ames Lab, 207 Met Dev, Ames, IA 50011 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 0-8031-2872-X J9 AM SOC TEST MATER PY 2000 VL 1392 BP 262 EP 275 PG 14 WC Materials Science, Ceramics; Materials Science, Characterization & Testing SC Materials Science GA BR55G UT WOS:000166791500018 ER PT S AU Cunningham, GS Lehovich, A AF Cunningham, GS Lehovich, A BE Hanson, KM TI 4D reconstructions from low-count SPECT data using deformable models with smooth interior intensity variations SO MEDICAL IMAGING 2000: IMAGE PROCESSING, PTS 1 AND 2 SE Proceedings of SPIE LA English DT Proceedings Paper CT Medical Imaging 2000 Conference CY FEB 13-17, 2000 CL SAN DIEGO, CA SP SPIE, Merge Technologies Inc, Amer Assoc Physicists Med, Amer Physiol Soc, FDA Ctr Devices & Radiol Hlth, IEEE, Soc Imaging Sci & Technol, Natl Elect Mfg Assoc, Diagnost Imaging & Therapy Syst Div, Radiol Soc N Amer, Soc Comp Applicat Radiol DE Bayesian inference; deformable models; Bezier patches; 4D reconstruction; dynamic cardiac SPECT ID TOMOGRAPHIC RECONSTRUCTION AB The Bayes Inference Engine (BIE) has been used to perform a 4D reconstruction of a first-pass radiotracer bolus distribution inside a CardioWest Total Artificial Heart, imaged with the University of Arizona's FastSPECT system. The BIE estimates parameter values that define the 3D model of the radiotracer distribution at each of 41 times spanning about two seconds. The 3D models have two components: a closed surface, composed of bi-quadratic Bezier triangular surface patches, that defines the interface between the part of the blood pool that contains radiotracer and the part that contains no radiotracer, and smooth voxel-to-voxel variations in intensity within the closed surface. Ideally, the surface estimates the ventricular wall location where the bolus is infused throughout the part of the blood pool contained by the right ventricle. The voxel-to-voxel variations are needed to model an inhomogenously-mixed bolus. Maximum a posterior (MAP) estimates of the Bezier control points and voxel values are obtained for each time frame. We show new reconstructions using the Bezier surface models, and discuss estimates of ventricular volume as a function of time, ejection fraction, and wall motion. The computation time for our reconstruction process, which directly estimates complex 3D model parameters from the raw data, is performed in a time that is competitive with more traditional voxel-based methods (ML-EM, e.g.). C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Cunningham, GS (reprint author), Los Alamos Natl Lab, POB 1663,MS P940, Los Alamos, NM 87544 USA. EM cunning@lanl.gov; lehovich@math.arizona.edu RI Cunningham, Gregory/F-1017-2011 OI Cunningham, Gregory/0000-0001-8819-4345 NR 9 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 0-8194-3596-1 J9 PROC SPIE PY 2000 VL 3979 BP 564 EP 574 DI 10.1117/12.387717 PG 3 WC Engineering, Biomedical; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BQ42Z UT WOS:000088355500056 ER PT S AU Maltz, JS AF Maltz, JS BE Hanson, KM TI Multiresolution constrained least-squares algorithm for direct estimation of time activity curves from dynamic ECT projection data SO MEDICAL IMAGING 2000: IMAGE PROCESSING, PTS 1 AND 2 SE Proceedings of SPIE LA English DT Proceedings Paper CT Medical Imaging 2000 Conference CY FEB 13-17, 2000 CL SAN DIEGO, CA SP SPIE, Merge Technologies Inc, Amer Assoc Physicists Med, Amer Physiol Soc, FDA Ctr Devices & Radiol Hlth, IEEE, Soc Imaging Sci & Technol, Natl Elect Mfg Assoc, Diagnost Imaging & Therapy Syst Div, Radiol Soc N Amer, Soc Comp Applicat Radiol DE dynamic ECT; dynamic SPECT; myocardial SPECT; kinetic parameter estimation; compartmental modeling; multiresolution methods; constrained linear least squares; quadratic programming ID MODEL; SPECT; PARAMETERS; MIXTURE; PET AB We present an algorithm which is able to reconstruct dynamic emission computed tomography (ECT) image series directly from inconsistent projection data that have been obtained using a rotating camera. By finding a reduced dimension time-activity curve (TAC) basis with which all physiologically feasible TAC's in an image may be accurately approximated, we are able to recast this large non-linear problem as one of constrained linear least squares (CLLSQ) and to reduce parameter vector dimension by a factor of 20. Implicit is the assumption that each pixel may be modeled using a single compartment model, as is typical in Tc-99m teboroxime wash-in wash-out studies; and that the blood input function is known. A disadvantage of the change of basis is that TAC non-negativity is no longer ensured. As a consequence, non-negativity constraints must appear in the CLLSQ formulation. A warm-start multiresolution approach is proposed, whereby the problem is initially solved at a resolution below that finally desired. At the next iteration, the number of reconstructed pixels is increased and the solution of the lower resolution problem is then used to warm-start the estimation of the higher resolution kinetic parameters. We demonstrate the algorithm by applying it to dynamic myocardial slice phantom projection data at resolutions of 16 x 16 and 32 x 32 pixels. We find that the warm-start method employed leads to computational savings of between 2 and 4 times when compared to cold start execution times. A 20% RMS error in the reconstructed TAC's is achieved for a total number of detected sinogram counts of 1 x 10(5) for the 16 x 16 problem and at 1 x 10(6) counts for the 32 x 32 grid. These errors are 1.5 - 2 times greater than those obtained in conventional (consistent projection) SPECT imaging at similar count levels. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. RP Maltz, JS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. NR 18 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 0-8194-3596-1 J9 PROC SPIE PY 2000 VL 3979 BP 586 EP 598 DI 10.1117/12.387719 PG 3 WC Engineering, Biomedical; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BQ42Z UT WOS:000088355500058 ER PT S AU Gleason, SS Sari-Sarraf, H Paulus, MJ Johnson, DK Abidi, MA AF Gleason, SS Sari-Sarraf, H Paulus, MJ Johnson, DK Abidi, MA BE Hanson, KM TI Automatic screening of polycystic kidney disease in x-ray CT images of laboratory mice SO MEDICAL IMAGING 2000: IMAGE PROCESSING, PTS 1 AND 2 SE Proceedings of SPIE LA English DT Proceedings Paper CT Medical Imaging 2000 Conference CY FEB 13-17, 2000 CL SAN DIEGO, CA SP SPIE, Merge Technologies Inc, Amer Assoc Physicists Med, Amer Physiol Soc, FDA Ctr Devices & Radiol Hlth, IEEE, Soc Imaging Sci & Technol, Natl Elect Mfg Assoc, Diagnost Imaging & Therapy Syst Div, Radiol Soc N Amer, Soc Comp Applicat Radiol DE computer-aided diagnosis; deformable models; active shape models; medical image segmentation; computer vision AB This paper describes the application of a statistical-based deformable model algorithm to the segmentation of kidneys in x-ray computed tomography (CT) images of laboratory mice. This segmentation algorithm has been developed as the crucial first step in a process to automatically screen mice for genetically-induced polycystic kidney disease (PKD). The algorithm is based on active shape models (ASMs) initially developed by Cootes, et. al. Once the segmentation is complete, texture measurements are applied within kidney boundaries to detect the presence of PKD. The challenges associated with the segmentation of mouse kidneys (non-rigid organs) are presented, and the motivation for using ASMs in this application is discussed. Also, improvements were made to published ASM methods that may be generally helpful in other segmentation applications. In 15 of the 18 cases tested, the mouse kidneys and spine were detected with only minor errors in boundary position. In the remaining three cases, small parts of the kidneys were missed acid/or some extra abdominal tissue was inadvertently included by the boundary. In all 18 cases, however, the kidneys were successfully detected at a level where PKD could be automatically screened for using mean-of-local-variance (MOLV) texture measurements. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Gleason, SS (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. EM gleasonss@ornl.gov NR 8 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 0-8194-3596-1 J9 PROC SPIE PY 2000 VL 3979 BP 837 EP 846 DI 10.1117/12.387747 PG 4 WC Engineering, Biomedical; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BQ42Z UT WOS:000088355500083 ER PT S AU Smither, RK Roa, DE AF Smither, RK Roa, DE BE Dobbins, JT Boone, JM TI Crystal diffraction lens for medical imaging SO MEDICAL IMAGING 2000: PHYSICS OF MEDICAL IMAGING SE Proceedings of SPIE LA English DT Proceedings Paper CT Medical Imaging 2000 Conference CY FEB 13-17, 2000 CL SAN DIEGO, CA SP SPIE, Merge Technologies Inc, Amer Assoc Physicists Med, Amer Physiol Soc, FDA Ctr Devices & Radiol Hlth, IEEE, Soc Imaging Sci & Technol, Natl Elect Mfg Assoc, Diagnost Imaging & Therapy Syst Div, Radiol Soc N Amer, Soc Comp Applicat Radiol DE crystal diffraction; lens; focusing; gamma rays; medical imaging; cancer; tumor AB A crystal diffraction lens for focusing energetic gamma rays has been developed at Argonne National Laboratory for use in medical imaging of radioactivity in the human body. A common method for locating possible cancerous growths in the body is to inject radioactivity into the blood stream of the patient and then look for any concentration of radioactivity that could be associated with the fast growing cancer cells. Often there are borderline indications of possible cancers that could be due to statistical functions in the measured counting rates. In order to determine if these indications are false or real, one must resort to surgical means and take tissue samples in the suspect area. We are developing a system of crystal diffraction lenses that will be incorporated into a 3-D imaging system with better sensitivity (factors of 10 to 20) and better spatial resolution (a few mm in both vertical and horizontal directions) than most systems presently in use. The use of this new imaging system will allow one to eliminate 90 percent of the false indications and both locate and determine the size of the cancer with mm precision. The lens consists of 900 single crystals of copper, 4 mm x 4 mm on a side and 2-4 mm thick, mounted in 13 concentric rings. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM rks@aps.anl.gov NR 9 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 0-8194-3594-5 J9 PROC SPIE PY 2000 VL 3977 BP 342 EP 352 DI 10.1117/12.384508 PG 11 WC Engineering, Biomedical; Optics; Physics, Applied; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Optics; Physics; Radiology, Nuclear Medicine & Medical Imaging GA BQ28C UT WOS:000087785900036 ER PT J AU Lee, CL Zhou, XL Kudchadker, RJ Harmon, F Harker, YD AF Lee, CL Zhou, XL Kudchadker, RJ Harmon, F Harker, YD TI A Monte Carlo dosimetry-based evaluation of the Li-7(p, n)Be-7 reaction near threshold for accelerator boron neutron capture therapy SO MEDICAL PHYSICS LA English DT Article DE epithermal neutrons; accelerator; neutron capture therapy; near threshold ID REQUIREMENTS; ELEMENTS; DESIGN; BEAMS AB Advanced methods of baron neutron capture therapy (BNCT) use an epithermal neutron beam in conjunction with tumor-targeting boron compounds for irradiation of glioblastomas and metastatic melanomas. A common neutron-producing reaction considered for accelerator-based BNCT is Li-7(p,n)Be-7, whose cross section increases very rapidly within several tens of keV of the reaction threshold at 1.88 MeV. Operation in the proton energy region near threshold will have an appreciable thick target neutron yield, but the neutrons produced will have relatively low energies that require little moderation to reach the epithermal range desirable for BNCT. Because of its relatively low projected accelerator cost and the portability of the neutron source/target assembly, BNCT based on the near-threshold technique is considered an attractive candidate for widespread hospital use. A systematic Monte Carlo N-Particle (MCNP) investigation of the dosimetric properties of near-threshold neutron beams has been performed. Results of these studies indicate that accelerator proton energies between 1.93 and 1.99 MeV, using 5 cm of H2O moderator followed by thin Li-6 and Pb shields, can provide therapeutically useful beams with treatment times less than one hour and accelerator currents less than 5 mA. (C) 2000 American Association of Physicists in Medicine. [S0094-2405(00)03101-1]. C1 MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Idaho State Univ, Dept Phys, Pocatello, ID 83209 USA. Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Lee, CL (reprint author), Los Alamos Natl Lab, X-11,MS F663, Los Alamos, NM 87545 USA. NR 29 TC 41 Z9 43 U1 1 U2 4 PU AMER ASSOC PHYSICISTS MEDICINE AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD JAN PY 2000 VL 27 IS 1 BP 192 EP 202 DI 10.1118/1.598884 PG 11 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 275VP UT WOS:000084841100028 PM 10659757 ER PT S AU Walraven, JA Soden, JM Tanner, DM Tangyunyong, P Cole, EI Anderson, RE Irwin, LW AF Walraven, JA Soden, JM Tanner, DM Tangyunyong, P Cole, EI Anderson, RE Irwin, LW BE Lawton, RA TI Electrostatic discharge/electrical overstress susceptibility in MEMS: A new failure mode SO MEMS RELIABILITY FOR CRITICAL APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on MEMS Reliability for Critical Applications CY SEP 20, 2000 CL SANTA CLARA, CA SP SPIE, Semicond Equipment & Mat Int, SolidState Technol, Sandia Natl Labs AB Electrostatic discharge (ESD) and electrical overstress (EOS) damage of Micro-Electro-Mechanical Systems (MEMS) has been identified as a new failure mode. This failure mode has not been previously recognized or addressed primarily due to the mechanical nature and functionality of these systems, as well as the physical failure signature that resembles stiction. Because many MEMS devices function by electrostatic actuation, the possibility of these devices not only being susceptible to ESD or EOS damage but also having a high probability of suffering catastrophic failure due to ESD or EOS is very teal. Results from previous experiments have shown stationary comb fingers adhered to the ground plane on MEMS devices tested in shock, vibration, and benign environments [1, 2]. Using Sandia polysilicon microengines, we have conducted tests to establish and explain the ESD/EOS failure mechanism of MEMS devices. These devices were electronically and optically inspected prior to and after ESD and EOS testing. This paper will address the issues surrounding MEMS susceptibility to ESD and EOS damage as well as describe the experimental method and results found from ESD and EOS testing. The tests were conducted using conventional IC failure analysis and reliability assessment characterization tools. In this paper we will also present a thermal model to accurately depict the heat exchange between an electrostatic comb finger and the ground plane during an ESD event. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Walraven, JA (reprint author), Sandia Natl Labs, POB 5800,MS 1081, Albuquerque, NM 87185 USA. NR 22 TC 25 Z9 25 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 1-8194-3836-7 J9 P SOC PHOTO-OPT INS PY 2000 VL 4180 BP 30 EP 39 DI 10.1117/12.395703 PG 10 WC Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Condensed Matter SC Engineering; Materials Science; Optics; Physics GA BR14Q UT WOS:000165733800004 ER PT S AU Walraven, JA Mani, SS Fleming, JG Headley, TJ Kotula, PG Pimentel, AA Rye, MJ Tanner, DM Smith, NF AF Walraven, JA Mani, SS Fleming, JG Headley, TJ Kotula, PG Pimentel, AA Rye, MJ Tanner, DM Smith, NF BE Lawton, RA TI Failure analysis of tungsten coated polysilicon micromachined microengines SO MEMS RELIABILITY FOR CRITICAL APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on MEMS Reliability for Critical Applications CY SEP 20, 2000 CL SANTA CLARA, CA SP SPIE, Semicond Equipment & Mat Int, SolidState Technol, Sandia Natl Labs DE tungsten; scanning electron microscopy; transmission electron microscopy; focused ion beam; electron energy loss spectroscopy; MEMS; atomic force microscopy AB Failure analysis (FA) tools have been applied to analyze tungsten coated polysilicon microengines. These devices were stressed under accelerated conditions at ambient temperatures and pressure. Preliminary results illustrating the failure modes of microengines operated under variable humidity and ultra-high drive frequency will also be shown. Analysis of tungsten coated microengines revealed the absence of wear debris in microengines operated under ambient conditions. Plan view imaging of these microengines using scanning electron microscopy (SEM) revealed no accumulation of wear debris on the surface of the gears or ground plane on microengines operated under standard laboratory conditions. Friction bearing surfaces were exposed and analyzed using the focused ion beam(FIB). These cross sections revealed no accumulation of debris along friction bearing surfaces. By using transmission electron microscopy (TEM) in conjunction with electron energy loss spectroscopy (EELS), we were able to identify the thickness, elemental analysis, and crystallographic properties of tungsten coated MEMS devices. Atomic force microscopy was also utilized to analyze the surface roughness of friction bearing surfaces. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Walraven, JA (reprint author), Sandia Natl Labs, POB 5800,MS 1081, Albuquerque, NM 87185 USA. RI Kotula, Paul/A-7657-2011 OI Kotula, Paul/0000-0002-7521-2759 NR 19 TC 13 Z9 13 U1 2 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 1-8194-3836-7 J9 P SOC PHOTO-OPT INS PY 2000 VL 4180 BP 49 EP 57 DI 10.1117/12.395708 PG 9 WC Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Condensed Matter SC Engineering; Materials Science; Optics; Physics GA BR14Q UT WOS:000165733800006 ER PT J AU Kobayashi, K Forte, TM Taniguchi, S Ishida, BY Oka, K Chan, L AF Kobayashi, K Forte, TM Taniguchi, S Ishida, BY Oka, K Chan, L TI The db/db mouse, a model for diabetic dyslipidemia: Molecular characterization and effects of Western diet feeding SO METABOLISM-CLINICAL AND EXPERIMENTAL LA English DT Article ID DENSITY-LIPOPROTEIN SUBCLASSES; MEDIATED GENE-TRANSFER; LEPTIN RECEPTOR; INSULIN-RESISTANCE; APOLIPOPROTEIN-E; ZUCKER RAT; LIPASE ACTIVITY; LA/N-CORPULENT; FATTY ZUCKER; SERUM-LIPIDS AB Diabetic dyslipidemia is a major factor contributing to the accelerated atherosclerosis in type 2 diabetes mellitus, Although several mouse models are available, the plasma lipoproteins in response to diet have not been fully characterized in these animals. In this study, we have characterized the plasma lipoproteins and related apolipoproteins, as well as the vascular lipases, in diabetes (db/db) mice and their nondiabetic controls (+/?) in the C57BL/KsJ strain. Within 6 weeks of age, db/db mice developed significant obesity, fasting hyperglycemia, and hyperinsulinemia. By FPLC analysis, db/db mice showed a prominent peak in the low-density lipoprotein (LDL) range that was absent in +/? mice, although high-density lipoprotein (HDL) was the predominant species in both groups of animals. Postheparin lipoprotein lipase (LPL) activity in db/db mice was 28% of the level in +/? mice. Upon feeding a human-like 0.15% (wt/wt) cholesterol and 21% (wt/wt) fat "Western" diet, db/db mice developed elevated plasma cholesterol, accompanied by an exaggerated apolipoprotein E (apoE) response compared with +/? mice. FPLC analysis showed that the marked hypercholesterolemic response in db/db mice was the result of a massive increase in the LDL region, which overshadowed a moderate increase in HDL. We next isolated lipoproteins by ultracentrifugation and characterized them by nondenaturing gradient gel electrophoresis. With regular chow, db/db mice had almost exclusively small dense LDL with a peak size at 21.4 nm, as compared with 26.6 nm in nondiabetic controls. On the Western diet, the small dense LDLs persisted but larger particles also appeared in db/db mice, whereas the size distribution in +/? mice was unchanged by the diet. Our results suggest that db/db mice fed a Western diet have a plasma lipoprotein phenotype that shows some similarities to that in patients with type 2 diabetes mellitus, and that db/db mice are a useful model to study the pathogenesis and treatment of diabetic dyslipidemia. Copyright (C) 2000 by W.B. Saunders Company. C1 Baylor Coll Med, Dept Cell Biol & Med, Houston, TX 77030 USA. USDA ARS, Childrens Nutr Res Ctr, Houston, TX USA. Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA USA. Univ Calif San Francisco, Dept Med, San Francisco, CA USA. RP Chan, L (reprint author), Baylor Coll Med, Dept Cell Biol & Med, 1 Bayer Pl, Houston, TX 77030 USA. FU NHLBI NIH HHS [HL 18574, HL 51586] NR 60 TC 115 Z9 122 U1 0 U2 10 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0026-0495 J9 METABOLISM JI Metab.-Clin. Exp. PD JAN PY 2000 VL 49 IS 1 BP 22 EP 31 DI 10.1016/S0026-0495(00)90588-2 PG 10 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 273XA UT WOS:000084733600005 PM 10647060 ER PT J AU Baxter, WJ Lesuer, DR Syn, CK AF Baxter, WJ Lesuer, DR Syn, CK TI Thermal activation of fatigue damage SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID TEMPERATURE-DEPENDENCE; COMPOSITES; ALUMINUM AB The effect of temperature on the fatigue of aluminum alloys results from a combination of thermally induced changes in the microstructure and the intrinsic temperature dependence of the fatigue process. These two effects are separated for the first time, and it is shown that the intrinsic fatigue process is thermally activated. Two distinct regimes are:identified. For fatigue lives <3 X 10(6) cycles, the activation energy is 86 kJ/mole in 339 aluminum/15 pet Kaowool composites and 120 kJ/mole in unreinforced 5086 aluminum, i.e., in the range reported for diffusion in aluminum. For fatigue lives >3 X 10(6) cycles, the activation energy is 240 kJ/mole. The magnitude of all three activation barriers decreases in direct proportion to the applied cyclic stress. These results are consistent with a dislocation model of jog formation at low cyclic stresses and the diffusion assisted motion of jogs at high cyclic stresses. The activation volumes correspond to dislocation loop lengths of 10 to 30 nm. C1 Gen Motors Res & Dev Ctr, Dept Met, Warren, MI 48090 USA. Univ Calif Lawrence Livermore Natl Lab, Dept Mat Technol, Livermore, CA 94551 USA. RP Baxter, WJ (reprint author), Gen Motors Res & Dev Ctr, Dept Met, Warren, MI 48090 USA. NR 24 TC 5 Z9 5 U1 0 U2 5 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 2000 VL 31 IS 1 BP 63 EP 69 DI 10.1007/s11661-000-0053-y PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 274JQ UT WOS:000084763100008 ER PT J AU Ishibashi, H Tobimatsu, H Matsumoto, T Hayashi, K Tomsia, AP Saiz, E AF Ishibashi, H Tobimatsu, H Matsumoto, T Hayashi, K Tomsia, AP Saiz, E TI Characterization of Mo-SiO2 functionally graded materials SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID METAL-CERAMIC COMPOSITES AB Mo/SiO2 functionally graded materials (FGMs) have been prepared by combined slip casting and sedimentation techniques. The final, sintered samples have a gradient in molybdenum content, with a maximum value of similar to 20 to 25 vol pet Mo. At one:edge, the FGM is a good electrical conductor (for approximately one-third of the total length), while the opposite end is composed mainly of fused SiO2. The variation of electrical resistivity, hardness, toughness, and thermal expansion along the gradient has been analyzed. The FGMs sintered In vacuum contained a small amount of Mo oxide (similar to 2 wt pct) as a third phase. The oxide originated from the starting Mo powders and oxidation during presintering. The oxide was in the form of discrete particles and did not appreciably affect the measured properties. The Mo content had the expected effect on the FGM properties; an increase in Mo increases resistivity, thermal expansion, and toughness. C1 TOTO Ltd, Kitakyushu, Fukuoka 8028601, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Ishibashi, H (reprint author), TOTO Ltd, Kitakyushu, Fukuoka 8028601, Japan. NR 22 TC 23 Z9 29 U1 0 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD JAN PY 2000 VL 31 IS 1 BP 299 EP 308 DI 10.1007/s11661-000-0074-6 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 274JQ UT WOS:000084763100029 ER PT S AU Loffler, JF Johnson, WL Wagner, W Thiyagarajan, P AF Loffler, JF Johnson, WL Wagner, W Thiyagarajan, P BE Eckert, J Schlorb, H Schultz, L TI Comparison of the decomposition and crystallization behavior of Zr and Pd based bulk amorphous alloys SO METASTABLE, MECHANICALLY ALLOYED AND NANOCRYSTALLINE MATERIALS, PTS 1 AND 2 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT International Symposium on Metastable, Mechanically Alloyed and Nanocrystalline Materials (ISMANAM-99) CY AUG 30-SEP 03, 1999 CL DRESDEN, GERMANY SP Deutsch Forech Gemeinsch, Inst Festkorper & Werkstofforsch Dresden, Sachsisches Minist Wissensch & Kunst, Fritsch GmbH, Stadtsparkasse Dresden, ZOZ GmbH DE bulk amorphous materials; crystallization; glass transition; phase separation; small-angle neutron scattering; undercooled liquid ID PHASE-SEPARATION; CYLINDER; GLASS AB The best metallic glass formers known so far are Vit1 (and similar alloys with a slight variation in composition) and Pd40Cu30Ni10P20. having critical cooling rates of about 1 Ws and glass transition temperatures T-g of around 636 K and 582 K, respectively, at a heating rate of 10 K/min. To compare the decomposition and crystallization behavior of these alloys, we performed small-angle neutron scattering (SANS) on the Vit1 derivative Zr42.6Ti12.4Cu11.25Ni10Be23.75 (Vit1A) and on Pd40Cu30Ni10P20 (PCNP) at temperatures near their T-g. The samples of Vit1A show interference peaks when annealed for several hours between 603 K and 643 K, giving evidence for decomposition on the nanometer scale. The SANS intensity monotonically increases in this temperature regime. An in-situ experiment, performed for 15 h at 621 K, with an average acquisition time of 20 min, resolves the time evolution of this decomposition. The SANS experiment on PCNP shows a completely different behavior. An in-situ SANS experiment performed on PCNP for 10 h at 571 K produced no scattering, but the SANS intensity changed drastically when the temperature was raised to 586 K. However, no interference maximum was observed in the SANS data for PCNP. X-ray diffraction data, measured after the in-situ experiments, resolve nanocrystals in Vit1A but a coarse-grained structure in PCNP. C1 CALTECH, WM Keck Lab, Pasadena, CA 91125 USA. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Loffler, JF (reprint author), CALTECH, WM Keck Lab, Pasadena, CA 91125 USA. NR 12 TC 24 Z9 24 U1 1 U2 4 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-858-3 J9 MATER SCI FORUM PY 2000 VL 343-3 BP 179 EP 184 PN 1&2 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BQ75R UT WOS:000089403900029 ER PT S AU Busmann, HG Pageler, A Brauneck, U Gruen, DM AF Busmann, HG Pageler, A Brauneck, U Gruen, DM BE Eckert, J Schlorb, H Schultz, L TI Grain boundaries and mechanical properties of nanocrystalline diamond films SO METASTABLE, MECHANICALLY ALLOYED AND NANOCRYSTALLINE MATERIALS, PTS 1 AND 2 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT International Symposium on Metastable, Mechanically Alloyed and Nanocrystalline Materials (ISMANAM-99) CY AUG 30-SEP 03, 1999 CL DRESDEN, GERMANY SP Deutsch Forech Gemeinsch, Inst Festkorper & Werkstofforsch Dresden, Sachsisches Minist Wissensch & Kunst, Fritsch GmbH, Stadtsparkasse Dresden, ZOZ GmbH DE grain boundaries; hardness; nanocrystalline diamond ID THIN-FILMS; CARBON; MICROSTRUCTURE; SPECTROSCOPY; DEPOSITION; MICROSCOPY; SURFACE; GROWTH AB Phase-pure nanocrystalline diamond thin films grown from plasmas of a hydrogen-poor carbon argon gas mixture have been analyzed regarding their hardness and elastic moduli by means of a micro indenter and a scanning acoustic microscope. The films are fully elastic, superhard and the moduli rival single crystalline diamond In addition, Raman spectroscopy with an excitation wavelength of 1064 nm shows a peak at 1438 1/cm and no peak above 1500 1/cm, and X-ray photoelectron spectroscopy a shake-up loss at 4,2 eV. This gives strong evidence for the existence of solitary double bonds in the films. The hardness and elasticity of the films are then explained by the assumption that the solitary double bonds interconnect the nanocrystals in the films, leading to an intergrain boundary adhesion of similar strength as the intragrain diamond cohesion. The results are in good agreement with recent simulations of high-energy grain boundaries. C1 Fraunhofer IFAM, DE-28359 Bremen, Germany. Schott Glas, DE-65203 Wiesbaden, Germany. Argonne Natl Lab, Div Chem & Mat Sci, Argonne, IL 60439 USA. RP Busmann, HG (reprint author), Fraunhofer IFAM, Wiener Str 12, DE-28359 Bremen, Germany. NR 27 TC 0 Z9 0 U1 0 U2 1 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-858-3 J9 MATER SCI FORUM PY 2000 VL 343-3 BP 255 EP 260 PN 1&2 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BQ75R UT WOS:000089403900040 ER PT S AU Nadutov, VM Garamus, VM Rawers, JC AF Nadutov, VM Garamus, VM Rawers, JC BE Eckert, J Schlorb, H Schultz, L TI Mossbauer and SANS study of Fe-powder mechanically alloyed with carbon SO METASTABLE, MECHANICALLY ALLOYED AND NANOCRYSTALLINE MATERIALS, PTS 1 AND 2 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT International Symposium on Metastable, Mechanically Alloyed and Nanocrystalline Materials (ISMANAM-99) CY AUG 30-SEP 03, 1999 CL DRESDEN, GERMANY SP Deutsch Forech Gemeinsch, Inst Festkorper & Werkstofforsch Dresden, Sachsisches Minist Wissensch & Kunst, Fritsch GmbH, Stadtsparkasse Dresden, ZOZ GmbH DE carbon; Fe-powder; mechanical alloying; Mossbauer spectroscopy; small angle neutron scattering AB Powder blends of Fe-powder and 2 wt. % graphite after mechanical alloying in Ar gas environment in high energy ball mill were studied by means of Mossbauer spectroscopy and small-angle neutron scattering (SANS) to characterize the change in the local iron environment and to examine the character of atomic and magnetic inhomogeneities. C1 Natl Acad Sci Ukraine, G Kurdyumov Inst Met Phys, UA-252680 Kiev, Ukraine. Joint Nucl Res Inst, Frank Lab Neutron Phys, RU-141980 Dubna, Russia. US Bur Mines, Albany Res Ctr, Albany, OR 97321 USA. RP Nadutov, VM (reprint author), Natl Acad Sci Ukraine, G Kurdyumov Inst Met Phys, 36 Vernadsky Blvd, UA-252680 Kiev, Ukraine. NR 12 TC 12 Z9 12 U1 0 U2 1 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-858-3 J9 MATER SCI FORUM PY 2000 VL 343-3 BP 721 EP 725 PN 1&2 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BQ75R UT WOS:000089403900112 ER PT B AU Burr, T Charlton, W Stanbro, WD AF Burr, T Charlton, W Stanbro, WD BE Valafar, F TI Comparison of signature pattern analysis methods in molecular epidemiology SO METMBS'00: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON MATHEMATICS AND ENGINEERING TECHNIQUES IN MEDICINE AND BIOLOGICAL SCIENCES, VOLS I AND II LA English DT Proceedings Paper CT International Conference on Mathematics and Engineering Techniques in Medicine and Biological Sciences (METMBS 00) CY JUN 26-29, 2000 CL LAS VEGAS, NV SP Comp Sci, Res, Educ & Applicat Press, Int Technol Inst, Korea Informat Processing Soc, PDPTA DE signature pattern analysis; epidemiology ID VIRUSES AB We consider the supervised learning problem of assigning test influenza sequences to their correct group (the group is the host species). Assume training cases (influenza sequences and their group labels) are available, usually via estimates of phylogenetic (evolutionary) trees as a special case of unsupervised learning. We compare conclusions under three supervised learning methods for sequences from the Nucleoprotein (NP) gene of the human influenza RNA virus from three host species. This data is available from the influenza database maintained at Los Alamos National Laboratory (http://linker.lanl.gov/flu/search_frame.html). C1 Univ Calif Los Alamos Natl Lab, Safeguards Syst Grp, Los Alamos, NM 87545 USA. RP Burr, T (reprint author), Univ Calif Los Alamos Natl Lab, Safeguards Syst Grp, NIS-7, Los Alamos, NM 87545 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-62-9 PY 2000 BP 473 EP 479 PG 7 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Engineering, Biomedical; Mathematics, Interdisciplinary Applications SC Computer Science; Engineering; Mathematics GA BR81W UT WOS:000167662700071 ER PT B AU Burr, T Myers, G Hyman, JM Skourikhine, A AF Burr, T Myers, G Hyman, JM Skourikhine, A BE Valafar, F TI Impacts of misspecifying the evolutionary model in phylogenetic tree estimation SO METMBS'00: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON MATHEMATICS AND ENGINEERING TECHNIQUES IN MEDICINE AND BIOLOGICAL SCIENCES, VOLS I AND II LA English DT Proceedings Paper CT International Conference on Mathematics and Engineering Techniques in Medicine and Biological Sciences (METMBS 00) CY JUN 26-29, 2000 CL LAS VEGAS, NV SP Comp Sci, Res, Educ & Applicat Press, Int Technol Inst, Korea Informat Processing Soc, PDPTA DE evolutionary model; coalescence; clades; distance measures; HIV; AIDS ID ENV GENE; NUCLEOTIDE AB We consider phylogenetic free estimation with emphasis on estimating the number of groups (clades). We rarely know the full evolutionary model, so we want to understand the impact of model estimation errors. Sensitivity to misspecifying the model or model parameters depends on how distinct the clades are, so it is important to consider differing degrees of clade resolution. We do this by varying the macroscopic growth rate and microscopic mutation rate of the tara. We simulate DNA sequence data using coalescent theory to simulate the sample genealogy, and one of several mutation models. For each case, we compute all pairwise distances between sequences using the true and several alternate models. The within-group variance (with distance data represented in principal coordinates) is used to choose the number of clades. We conclude that the estimated number of clades can be sensitive to model estimation errors, to an. extent determined by clade resolution. C1 Univ Calif Los Alamos Natl Lab, Safeguards Syst Grp, Los Alamos, NM 87545 USA. RP Burr, T (reprint author), Univ Calif Los Alamos Natl Lab, Safeguards Syst Grp, NIS-7, Los Alamos, NM 87545 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-62-9 PY 2000 BP 481 EP 487 PG 7 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Engineering, Biomedical; Mathematics, Interdisciplinary Applications SC Computer Science; Engineering; Mathematics GA BR81W UT WOS:000167662700072 ER PT B AU Charlton, WS Burr, T Stanbro, WD Budlong-Sylvester, K Gattiker, J AF Charlton, WS Burr, T Stanbro, WD Budlong-Sylvester, K Gattiker, J BE Valafar, F TI Simulation tool for predicting classical epidemiology data for infectious diseases using a probabilistic model SO METMBS'00: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON MATHEMATICS AND ENGINEERING TECHNIQUES IN MEDICINE AND BIOLOGICAL SCIENCES, VOLS I AND II LA English DT Proceedings Paper CT International Conference on Mathematics and Engineering Techniques in Medicine and Biological Sciences (METMBS 00) CY JUN 26-29, 2000 CL LAS VEGAS, NV SP Comp Sci, Res, Educ & Applicat Press, Int Technol Inst, Korea Informat Processing Soc, PDPTA DE epidemiology; Monte Carlo; simulation; infectious disease ID HIV AB A computational tool for predicting classical epidemiological data simulating the spread of an infectious disease is under development at Los Alamos National Laboratory. This tool performs spatial and temporal transport of the infectious disease using a Monte Carlo based model. The human transport method used in the tool draws much of its origin from Monte Carlo based approaches in radiation transport. Transmission and viral infectivity are represented by probability distribution functions derived from literature data. The tool allows for the grouping of populations based on sex, age, social group, geographic locations, and ethnicity. The methodology used in the simulations and a plan for model validation are described in detail in the paper. The tool is computationally intensive; however, the approach used here has several advantages over deterministic models including the ability to readily include numerous parameters and the ability to effectively simulate the early stages of an epidemic. The tool's other advantages and disadvantages are compared to the characteristics of previous modeling efforts. Upon completion, the tool will be used to aid in estimating the impact of central measures on disease spread, devising effective strategies to minimize the impact and spread of infectious diseases, increasing the database available for infectious diseases through an inverse problem analysis of known disease spreads, and understanding the development and spread of resistant strains. C1 Univ Calif Los Alamos Natl Lab, Safeguards Syst Grp, Los Alamos, NM 87545 USA. RP Charlton, WS (reprint author), Univ Calif Los Alamos Natl Lab, Safeguards Syst Grp, NIS-7, Los Alamos, NM 87545 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-62-9 PY 2000 BP 489 EP 495 PG 7 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Engineering, Biomedical; Mathematics, Interdisciplinary Applications SC Computer Science; Engineering; Mathematics GA BR81W UT WOS:000167662700073 ER PT J AU Stoffel, TL Reda, I Myers, DR Renne, D Wilcox, S Treadwell, J AF Stoffel, TL Reda, I Myers, DR Renne, D Wilcox, S Treadwell, J TI Current issues in terrestrial solar radiation instrumentation for energy, climate, and space applications SO METROLOGIA LA English DT Article; Proceedings Paper CT 7th International Conference on Radiometry CY OCT 25-27, 1999 CL MADRID, SPAIN AB Uncertainty in terrestrial solar radiation measurements of a few watts per square metre (1 W/m(2) to 2 W/m(2)) is needed to validate estimates of the Earth's radiation balance derived from satellite data. The characterization of solar energy resources for renewable energy technologies requires similar accuracy for economical technology deployment. Solar radiation measurement research at the National Renewable Energy Laboratory addresses calibrations, operational characteristics, and corrections for terrestrial solar radiation measurements. The characterization of field instrument geometric and thermal responses contributing to radiometric errors is described, together with correction schemes reducing the uncertainty of broadband irradiance measurements from tens of watts per square metre to a few (+/- 2 W/m(2) to +/- 5 W/m(2)). Such improvements in accuracy reduce the time and labour required for detecting and quantifying trends in terrestrial solar radiation acid possible changes in the Earth's radiation budget. C1 NREL, Golden, CO 80401 USA. RP Stoffel, TL (reprint author), NREL, 1617 Cole Blvd, Golden, CO 80401 USA. NR 17 TC 9 Z9 9 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0026-1394 EI 1681-7575 J9 METROLOGIA JI Metrologia PY 2000 VL 37 IS 5 BP 399 EP 402 DI 10.1088/0026-1394/37/5/11 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 403WX UT WOS:000167066700011 ER PT S AU Tobin, KW Karnowski, TP Lakhani, F AF Tobin, KW Karnowski, TP Lakhani, F BE Sullivan, NT TI A survey of semiconductor data management systems technology SO METROLOGY, INSPECTION, AND PROCESS CONTROL FOR MICROLITHOGRAPHY XIV 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 XIV CY FEB 28-MAR 02, 2000 CL SANTA CLARA, CA SP Int Soc Opt Engn, Semiconduct Equipment & Mat Int, Int SEMATECH DE industry survey; yield management; data management system; database; datamining; knowledge discovery; automatic defect classification; spatial signature analysis; statistical process control AB As integrated circuit fabrication processes continue to increase in complexity, it has been observed that data collection, retention, and retrieval rates are continuing to increase at an alarming rate. At future technology nodes, the time required to source manufacturing problems must at least remain constant to maintain anticipated productivity. Current commercial and manufacturer in-house data management systems (DMS) have limited functionality in their ability to access, analyze, and intelligently extract information from the large variety of manufacturing data sources available within the semiconductor manufacturing site. II is critical that the semiconductor industry agree on a strategic R&D plan to develop a family of DMS technologies to simultaneously access multiple data sources and derive useful defect and yield information from that data via analysis algorithms. The Oak Ridge National Laboratory (ORNL) and SEMATECH performed an industry-wide survey of semiconductor device manufacturers and the suppliers of data management tools and systems in the Spring of 1999. The purpose of the survey was to determine: (1) the state-of-the-art in DMS technologies and systems; (2) limitations of the systems in use today; (3) technology gaps impacting future DMS development, and; (4) input for future strategic R&D activities. This paper describes the results of this survey and presents a prioritized R&D roadmap. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Tobin, KW (reprint author), Oak Ridge Natl Lab, POB 2008,Bldg 3546,MS-6011, Oak Ridge, TN 37831 USA. RI Escarabajal, Juan Antonio/C-5644-2012 NR 14 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 0-8194-3616-X J9 P SOC PHOTO-OPT INS PY 2000 VL 3998 BP 248 EP 257 PG 10 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BQ59Z UT WOS:000088918400026 ER PT S AU Hunt, MA Goddard, JS Mullens, JA Ferrell, RK Whitus, BR Ben-Porath, A AF Hunt, MA Goddard, JS Mullens, JA Ferrell, RK Whitus, BR Ben-Porath, A BE Sullivan, NT TI Paradigm for selecting the optimum classifier in semiconductor automatic defect classification applications SO METROLOGY, INSPECTION, AND PROCESS CONTROL FOR MICROLITHOGRAPHY XIV 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 XIV CY FEB 28-MAR 02, 2000 CL SANTA CLARA, CA SP Int Soc Opt Engn, Semiconduct Equipment & Mat Int, Int SEMATECH DE automatic defect classification; pattern recognition; semiconductor inspection; nonparametric supervised classifiers ID NEURAL NETWORKS AB The automatic classification of defects found on semiconductor wafers using a scanning electron microscope (SEM) is a complex task that involves many steps. The process includes re-detecting the defect, measuring attributes of the defect, and automatically assigning a classification. In many cases, especially during product ramp-up, and when multiple products are manufactured in the same line, there are few training examples for an automatic defect classification (ADC) system. This condition presents a problem for traditional supervised parametric and nonparametric learning techniques. In this paper we investigate the attributes of several approaches to ADC and compare their performance under a variety of available training data scenarios. We have selected to characterize the attributes and performance of a traditional K-nearest neighbor classifier, probabilistic neural net-work (PNN), and rule-based classifier in the context of SEM ADC. The PNN classifier is a nonparametric supervised classifier that is built around a radial basis function (RBF) neural network architecture. A basic summary of the PNN will be presented along with the generic strengths and weakness described in the literature and observed with actual semiconductor defect data. The PNN classifier is able to manage conditions such as non-convex class distributions and single class multiple clusters in feature space. A rule-based classifier producing built-in core classes provided by the Applied Materials SEMVision tool will be characterized in the context. of both few examples and no examples. An extensive set of fab generated data is used to characterize the performance of these ADC approaches. Typical data sets contain from 30 to greater than 200. The number of classes in the data set range from 4 to more than 12. The conclusions reached from this analysis indicate that the strengths of each method are evident under specific conditions that are related to different stages within the VLSI yield curve, and to the number of different products in the line. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hunt, MA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3616-X J9 P SOC PHOTO-OPT INS PY 2000 VL 3998 BP 269 EP 276 DI 10.1117/12.386481 PG 8 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BQ59Z UT WOS:000088918400028 ER PT S AU Berger, KW Campiotti, RH AF Berger, KW Campiotti, RH BE Sullivan, NT TI Absolute dosimetry for extreme ultraviolet lithography SO METROLOGY, INSPECTION, AND PROCESS CONTROL FOR MICROLITHOGRAPHY XIV 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 XIV CY FEB 28-MAR 02, 2000 CL SANTA CLARA, CA SP Int Soc Opt Engn, Semiconduct Equipment & Mat Int, Int SEMATECH DE EUV; extreme ultraviolet lithography; dosimetry AB The accurate measurement of an exposure dose reaching the wafer on an extreme ultraviolet (EUV) lithographic system has been a technical challenge directly applicable to the evaluation of candidate EUV resist materials and calculating lithography system throughputs. We have developed a dose monitoring sensor system that can directly measure EUV intensities at the wafer plane of a prototype EUV lithographic system. This sensor system, located on the wafer stage adjacent to the electrostatic chuck used to grip wafers, operates by translating the sensor into the aerial image, typically illuminating an "open" (unpatterned) area on the reticle. The absolute signal strength can be related to energy density at the wafer, and thus used to determine resist sensitivity, and the signal as a function of position can be used to determine illumination uniformity at the wafer plane. Spectral filtering to enhance the detection of 13.4 nm radiation was incorporated into the sensor. Other critical design parameters include the packaging and amplification technologies required to place this device into the space and vacuum constraints of a EUV lithography environment. We describe two approaches used to determine the absolute calibration of this sensor. The first conventional approach requires separate characterization of each element of the sensor. A second novel approach uses x-ray emission from a mildly radioactive iron source to calibrate the absolute response of the entire sensor system (detector and electronics) in a single measurement. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Berger, KW (reprint author), POB 969,MS 9409, Livermore, CA 94550 USA. NR 3 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 0-8194-3616-X J9 P SOC PHOTO-OPT INS PY 2000 VL 3998 BP 838 EP 845 DI 10.1117/12.386448 PG 8 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BQ59Z UT WOS:000088918400090 ER PT S AU Gourley, PL McDonald, AE Hendricks, JK Copeland, GC Hunter, J Akhil, O Cheung, D Cox, J Capps, H Curry, M Skirboll, SL AF Gourley, PL McDonald, AE Hendricks, JK Copeland, GC Hunter, J Akhil, O Cheung, D Cox, J Capps, H Curry, M Skirboll, SL BE Mariella, RP TI Detecting cancer quickly and accurately SO MICRO- AND NANOTECHNOLOGY FOR BIOMEDICAL AND ENVIRONMENTAL APPLICATIONS SE PROGRESS IN BIOMEDICAL OPTICS LA English DT Proceedings Paper CT Conference on Micro- and Nanotechnology for Biomedical and Environmental Applications CY JAN 26-27, 2000 CL SAN JOSE, CA SP USAF, Off Sci Res, SPIE, Int Biomed Opt Sci ID SEMICONDUCTOR AB We present a new technique for high throughput screening of tumor cells in a sensitive nanodevice that has the potential to quickly identify a cell population that has begun the rapid protein synthesis and mitosis characteristic of cancer cell proliferation. Currently, pathologists rely on microscopic examination of cell morphology using century-old staining methods that are labor-intensive, time-consuming and frequently in error. New micro-analytical methods (1-6) for automated, real time screening without chemical modification are critically needed to advance pathology and improve diagnoses. We have teamed scientists with physicians to create a microlaser biochip (based upon our R&D award winning bio-laser concept) which evaluates tumor cells by quantifying their growth kinetics. The key new discovery was demonstrating that the lasing spectra are sensitive to the biomolecular mass in the cell, which changes the speed of light in the laser microcavity. initial results with normal and cancerous human brain cells show that only a few hundred cells - the equivalent of a billionth of a liter - are required to detect abnormal growth. The ability to detect cancer in such a minute tissue sample is crucial for resecting a tumor margin or grading highly localized tumor malignancy. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Gourley, PL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 20 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 1017-2661 BN 0-8194-3528-7 J9 PROG BIOM O PY 2000 VL 1 BP 2 EP 10 PG 9 WC Engineering, Biomedical; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BP95B UT WOS:000086711200001 ER PT S AU Kallman, JS Ashby, AE Ciarlo, DR Thomas, GH AF Kallman, JS Ashby, AE Ciarlo, DR Thomas, GH BE Mariella, RP TI OPUS: an optically parallel ultrasound sensor SO MICRO- AND NANOTECHNOLOGY FOR BIOMEDICAL AND ENVIRONMENTAL APPLICATIONS SE PROGRESS IN BIOMEDICAL OPTICS LA English DT Proceedings Paper CT Conference on Micro- and Nanotechnology for Biomedical and Environmental Applications CY JAN 26-27, 2000 CL SAN JOSE, CA SP USAF, Off Sci Res, SPIE, Int Biomed Opt Sci DE optical MEMS; ultrasound; transmission imaging ID DIFFRACTION TOMOGRAPHY; ALGORITHM; FIELD AB Transmission ultrasound is not in widespread use, partially because of the time and expense of acquiring the data. We are addressing this problem with an optically parallel ultrasound sensor. The core of the sensor is a thin silicon nitride membrane patterned with gold to create "acoustic pixels" over a large area. Each acoustic pixel vibrates at the frequency of the acoustic excitation. The thin membrane, supported by short walls over an optical substrate, with one side immersed in the ultrasound medium and the supported side exposed to air, flexes when an ultrasound pressure wave encounters it. This flexing causes the air gap between the optical substrate and the membrane to change. The change in the air gap modulates the reflection of an optical beam by frustrated total internal reflection. By strobing the optical beam, the deflection of the membrane can be detected and measured at any point through the acoustic period. Acquiring a sequence of images allow us to extract the relative pressure phase and amplitude. Proof of principle experiments have shown that we can build this sensor, and we are currently using a small aperture version to examine simple test objects. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, L-154, Livermore, CA 94550 USA. EM kallman1@llnl.gov NR 11 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 1017-2661 BN 0-8194-3528-7 J9 PROG BIOM O PY 2000 VL 1 BP 64 EP 73 DI 10.1117/12.379582 PG 10 WC Engineering, Biomedical; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BP95B UT WOS:000086711200008 ER PT S AU Pocha, MD Garrett, HE Patel, RR Jones, LM Larson, MC Emanuel, MA Bond, SW Deri, RJ Drayton, RF Petersen, HE Lowry, ME AF Pocha, MD Garrett, HE Patel, RR Jones, LM Larson, MC Emanuel, MA Bond, SW Deri, RJ Drayton, RF Petersen, HE Lowry, ME BE Mariella, RP TI Glass, plastic & semiconductors: Packaging techniques for miniature optoelectronic components SO MICRO- AND NANOTECHNOLOGY FOR BIOMEDICAL AND ENVIRONMENTAL APPLICATIONS SE PROGRESS IN BIOMEDICAL OPTICS LA English DT Proceedings Paper CT Conference on Micro- and Nanotechnology for Biomedical and Environmental Applications CY JAN 26-27, 2000 CL SAN JOSE, CA SP USAF, Off Sci Res, SPIE, Int Biomed Opt Sci DE silicon microbench; packaging; multiwavelength VCSELS; ball lenses; wavelength selective filters; WDM; optical communications ID MULTIMODE WDM AB At Lawrence Livermore National Laboratory, Eve have extensive experience with the design and development of miniature photonic systems which require novel packaging schemes. Over the years we have developed silicon micro-optical benches to serve as a stable platform for precision mounting of optical and electronic components. We have developed glass ball lenses that can be fabricated in-situ on the microbench substrate. We have modified commercially available molded plastic fiber ribbon connectors (MT) and added thin film multilayer semiconductor coatings to create potentially low-cost wavelength combiners and wavelength selective filters. We have fabricated both vertical-cavity and in-plane semiconductor lasers and amplifiers, and have packaged these and other components into several miniature photonics systems. For example, we have combined the silicon optical bench with standard electronic packaging techniques and our custom-made wavelength-selective filters to develop a four-wavelength wavelength-division-multiplexing transmitter module mounted in a standard 120-pin ceramic PGA package that couples light from several vertical-cavity-surface-emitting-laser arrays into one multimode fiber-ribbon array. The coupling loss can be as low as 2dB, and the transmitters can be operated at over 1.25 GHz. While these systems were not designed for biomedical or environmental applications, the concepts and techniques are general and widely applicable. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Pocha, MD (reprint author), Lawrence Livermore Natl Lab, POB 808,L-222, Livermore, CA 94551 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 1017-2661 BN 0-8194-3528-7 J9 PROG BIOM O PY 2000 VL 1 BP 130 EP 140 PG 11 WC Engineering, Biomedical; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BP95B UT WOS:000086711200015 ER PT B AU Jacobson, SC McClain, MA Culbertson, CT Ramsey, JM AF Jacobson, SC McClain, MA Culbertson, CT Ramsey, JM BE VandenBerg, A Bergveld, P Olthuis, W TI Microfabricated fluidic devices for cellular assays SO MICRO TOTAL ANALYSIS SYSTEMS 2000, PROCEEDINGS SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000) CY MAY 14-18, 2000 CL ENSCHEDE, NETHERLANDS SP MESA+, Analyt Chem, Microcosm, Jenoptik, Hewlett Packard, 3T, Cepheid, Twente MicroProd, Univ Twente DE microchip; fluidics; cytometry; cells ID CHIP AB Flow cytometry was demonstrated on a glass microchip fabricated using standard photolithographic techniques. The channel walls were coated to prevent cell adhesion, and the cells were transported electrophotetically by applying potentials to the fluid reservoirs. The sample stream was electrophoretically focused in two dimensions at a cross intersection to enable single cell interrogation. An Escherichia coli sample was labeled on-chip with a membrane permeable nucleic acid stain Syto IS, and coincident light scattering and fluorescence data were obtained from the these labeled cells. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Jacobson, SC (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6387-6 J9 MESA MG PY 2000 BP 107 EP 110 PG 4 WC Biotechnology & Applied Microbiology; Chemistry, Analytical; Engineering, Mechanical; Instruments & Instrumentation SC Biotechnology & Applied Microbiology; Chemistry; Engineering; Instruments & Instrumentation GA BR72M UT WOS:000167335400024 ER PT B AU Ramsey, JM Jacobson, SC Culbertson, CT Ramsey, RS AF Ramsey, JM Jacobson, SC Culbertson, CT Ramsey, RS BE VandenBerg, A Bergveld, P Olthuis, W TI Microfabricated intrachannel electrical contacts for material transport control SO MICRO TOTAL ANALYSIS SYSTEMS 2000, PROCEEDINGS SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000) CY MAY 14-18, 2000 CL ENSCHEDE, NETHERLANDS SP MESA+, Analyt Chem, Microcosm, Jenoptik, Hewlett Packard, 3T, Cepheid, Twente MicroProd, Univ Twente DE microfluidics; electrophoresis; salt bridge; bonding techniques ID SAMPLE AB Interest in microfabricated fluidic channel structures (microchips) has grown tremendously over the past decade due to the large number of powerful demonstrations that have appeared in the literature. The diversity of chemical and biochemical measurement techniques implemented on microchips is large including various electrophoretic and chromatographic separations, chemical and enzymatic reactions, noncovalent recognition interactions, sample concentration enhancement, and cellular manipulations. In addition the types of samples addressed by microchips has been broad in scope, e.g., small ions and molecules, single and double stranded DNA, amino acids, peptides, and proteins. The most popular method for inducing material transport through microchip channels has been by electrokinetic means. i.e., electrophoretic transport of ions and electroosmotic bulk fluid flow. Electrokinetic transport, although not the panacea, has proven quite effective for simple devices and has the convenience of only requiring simple electrical connections between a device controller and the microchip. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ramsey, JM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 3 TC 2 Z9 2 U1 2 U2 2 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6387-6 J9 MESA MG PY 2000 BP 213 EP 216 PG 4 WC Biotechnology & Applied Microbiology; Chemistry, Analytical; Engineering, Mechanical; Instruments & Instrumentation SC Biotechnology & Applied Microbiology; Chemistry; Engineering; Instruments & Instrumentation GA BR72M UT WOS:000167335400049 ER PT B AU Culbertson, CT Jacobson, SC Ramsey, JM AF Culbertson, CT Jacobson, SC Ramsey, JM BE VandenBerg, A Bergveld, P Olthuis, W TI High efficiency separations on microchip devices SO MICRO TOTAL ANALYSIS SYSTEMS 2000, PROCEEDINGS SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000) CY MAY 14-18, 2000 CL ENSCHEDE, NETHERLANDS SP MESA+, Analyt Chem, Microcosm, Jenoptik, Hewlett Packard, 3T, Cepheid, Twente MicroProd, Univ Twente DE microchip; separations; amino acid analysis ID ELECTROPHORESIS AB We have fabricated a glass microchip with a spiral shaped separation channel which is 25 cm long, but whose footprint is only 5 cm x 5 cm. With this design, dynamic dispersion, in excess to that generated by diffusion, is limited to less than 11% of the total dynamic dispersion, and electrophoretic separation efficiencies for dichlorofluorscein of over 1,000,000 theoretical plates have been achieved in under 46 seconds. The number of theoretical plates generated increased linearly with the applied voltage, and at the highest field strength applied the rate of theoretical plate generation was 21,000 plates/s. Similar results have also been obtained in a micellar separation of amino acids. The number of theoretical plates generated on the spiral microchip are two to three times higher than typically generated using conventional CE, and the separations, for example, of amino acids are 5 to 10 times faster. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Culbertson, CT (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 5 TC 2 Z9 2 U1 2 U2 5 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6387-6 J9 MESA MG PY 2000 BP 221 EP 224 PG 4 WC Biotechnology & Applied Microbiology; Chemistry, Analytical; Engineering, Mechanical; Instruments & Instrumentation SC Biotechnology & Applied Microbiology; Chemistry; Engineering; Instruments & Instrumentation GA BR72M UT WOS:000167335400051 ER PT B AU Frye-Mason, G Kottenstette, R Lewis, P Heller, E Manginell, R Adkins, D Dulleck, G Martinez, D Sasaki, D Mowry, C Matzke, C Anderson, L AF Frye-Mason, G Kottenstette, R Lewis, P Heller, E Manginell, R Adkins, D Dulleck, G Martinez, D Sasaki, D Mowry, C Matzke, C Anderson, L BE VandenBerg, A Bergveld, P Olthuis, W TI Hand-held miniature chemical analysis system (mu ChemLab) for detection of trace concentrations of gas phase analytes SO MICRO TOTAL ANALYSIS SYSTEMS 2000, PROCEEDINGS SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000) CY MAY 14-18, 2000 CL ENSCHEDE, NETHERLANDS SP MESA+, Analyt Chem, Microcosm, Jenoptik, Hewlett Packard, 3T, Cepheid, Twente MicroProd, Univ Twente DE sample concentrator; gas chromatograph; GC; surface acoustic wave; SAW AB A miniature, integrated chemical laboratory (mu ChemLab) is being developed that utilizes microfabrication to provide faster response, smaller size, lower power operation, and an ability to utilize multiple analysis channels for enhanced versatility and chemical discrimination. Improved sensitivity and selectivity are achieved with three cascaded components: (1) a sample collector/concentrator, (2) a gas chromatographic (GC) separator, and (3) a chemically selective surface acoustic wave (SAW) array detector. Prototypes of all three components have been developed and demonstrated both individually and when integrated on a novel electrical and fluidic printed circuit board. A hand-held autonomous system containing two analysis channels and all supporting electronics and user interfaces is currently being assembled and tested. C1 Sandia Natl Labs, Microsensor R&D Dept, Albuquerque, NM 87185 USA. RP Frye-Mason, G (reprint author), Sandia Natl Labs, Microsensor R&D Dept, POB 5800,MS-1425, Albuquerque, NM 87185 USA. NR 4 TC 8 Z9 8 U1 1 U2 3 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6387-6 J9 MESA MG PY 2000 BP 229 EP 232 PG 4 WC Biotechnology & Applied Microbiology; Chemistry, Analytical; Engineering, Mechanical; Instruments & Instrumentation SC Biotechnology & Applied Microbiology; Chemistry; Engineering; Instruments & Instrumentation GA BR72M UT WOS:000167335400053 ER PT B AU Fuller, CK Hamilton, J Ackler, H Krulevitch, P Boser, B Eldredge, A Becker, F Yang, J Gascoyne, P AF Fuller, CK Hamilton, J Ackler, H Krulevitch, P Boser, B Eldredge, A Becker, F Yang, J Gascoyne, P BE VandenBerg, A Bergveld, P Olthuis, W TI Microfabricated multi-frequency particle impedance characterization system SO MICRO TOTAL ANALYSIS SYSTEMS 2000, PROCEEDINGS SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000) CY MAY 14-18, 2000 CL ENSCHEDE, NETHERLANDS SP MESA+, Analyt Chem, Microcosm, Jenoptik, Hewlett Packard, 3T, Cepheid, Twente MicroProd, Univ Twente DE coulter counter; cell impedance; cell capacitance; electrorotation; MEMS ID ELECTROROTATION; CELLS AB We have developed a microfabricated flow-through impedance characterization system capable of performing AC, multi-frequency measurements on cells and other particles. The sensor measures both the resistive and reactive impedance of passing particles, at rates of up to 100 particles per second. Its operational bandwidth approaches 10 MHz with a signal-to-noise ratio of approximately 40 dB. Particle impedance is measured at three or more Frequencies simultaneously, enabling the derivation of multiple particle parameters. This constitutes an improvement to the well-established technique of DC particle sizing via the Coulter Principle. Human peripheral blood granulocyte radius, membrane capacitance, and cytoplasmic conductivity were measured (r = 4.1 mum, C-mem = 0.9 muF/cm(2), sigma (int) = 0.66 S/m) and were found to be consistent with published values. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Microtechnol, Livermore, CA 94550 USA. RP Fuller, CK (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Microtechnol, Livermore, CA 94550 USA. NR 6 TC 12 Z9 12 U1 1 U2 4 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6387-6 J9 MESA MG PY 2000 BP 265 EP 268 PG 4 WC Biotechnology & Applied Microbiology; Chemistry, Analytical; Engineering, Mechanical; Instruments & Instrumentation SC Biotechnology & Applied Microbiology; Chemistry; Engineering; Instruments & Instrumentation GA BR72M UT WOS:000167335400060 ER PT B AU Ermakov, SV Jacobson, SC Ramsey, JM AF Ermakov, SV Jacobson, SC Ramsey, JM BE VandenBerg, A Bergveld, P Olthuis, W TI Computer simulations of electrokinetic sample manipulations in microfluidic devices SO MICRO TOTAL ANALYSIS SYSTEMS 2000, PROCEEDINGS SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000) CY MAY 14-18, 2000 CL ENSCHEDE, NETHERLANDS SP MESA+, Analyt Chem, Microcosm, Jenoptik, Hewlett Packard, 3T, Cepheid, Twente MicroProd, Univ Twente DE computer simulation; electrokinetic mass transport; gated injection; sample leakage AB Sample injection is one of the sample manipulations steps used in microfabricated fluidic devices. One particular type of electrokinetic injection, a gated injection technique,(1) was studied by means of computer modeling. Computer simulations were based on the mathematical model described earlier.(2) Experimental data such as concentration distribution and sample detector signal compared against simulation results demonstrated good agreement. Particular attention was paid to possible sample leakage during the sample loading step. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ermakov, SV (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6387-6 J9 MESA MG PY 2000 BP 291 EP 294 PG 4 WC Biotechnology & Applied Microbiology; Chemistry, Analytical; Engineering, Mechanical; Instruments & Instrumentation SC Biotechnology & Applied Microbiology; Chemistry; Engineering; Instruments & Instrumentation GA BR72M UT WOS:000167335400066 ER PT B AU Lazar, IM Ramsey, RS Ramsey, JM AF Lazar, IM Ramsey, RS Ramsey, JM BE VandenBerg, A Bergveld, P Olthuis, W TI Microchip-nano-electrospray device for rapid on-chip digestion and mass spectrometric analysis of hemoglobin variants SO MICRO TOTAL ANALYSIS SYSTEMS 2000, PROCEEDINGS SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000) CY MAY 14-18, 2000 CL ENSCHEDE, NETHERLANDS SP MESA+, Analyt Chem, Microcosm, Jenoptik, Hewlett Packard, 3T, Cepheid, Twente MicroProd, Univ Twente DE microchips; TOFMS; hemoglobins AB The emerging technology of microfabrication has generated devices that enable the completion of complex chemical processes on highly integrated miniaturized platforms. We have recently developed a microchip-nanoelectrospray device capable of providing subattomole sensitivity for peptide and protein samples [1]. A major advantage of this miniaturized electrospray platform is that it can operate as a stand-alone device, without any external assistance for stabilizing the electrospray. In this present manuscript we report on its applicability to the rapid analysis of on-chip generated proteolytic digestion fragments of hemoglobin variants using time-of-flight mass spectrometric (TOFMS) detection. The amount of initial protein consumed, sufficient for positive identification using peptide mass fingerprinting, ranges in the low femtomole to attomole region. C1 Oak Ridge Natl Lab, Chem & Analyt Sci Div, Oak Ridge, TN 37831 USA. RP Lazar, IM (reprint author), Oak Ridge Natl Lab, Chem & Analyt Sci Div, Oak Ridge, TN 37831 USA. OI Lazar, Iulia/0000-0001-7746-7889 NR 4 TC 1 Z9 1 U1 1 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6387-6 J9 MESA MG PY 2000 BP 379 EP 382 PG 4 WC Biotechnology & Applied Microbiology; Chemistry, Analytical; Engineering, Mechanical; Instruments & Instrumentation SC Biotechnology & Applied Microbiology; Chemistry; Engineering; Instruments & Instrumentation GA BR72M UT WOS:000167335400088 ER PT B AU Fintschenko, Y Ngola, SM Shepodd, TJ Arnold, DW AF Fintschenko, Y Ngola, SM Shepodd, TJ Arnold, DW BE VandenBerg, A Bergveld, P Olthuis, W TI On-chip packed channel separations SO MICRO TOTAL ANALYSIS SYSTEMS 2000, PROCEEDINGS SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000) CY MAY 14-18, 2000 CL ENSCHEDE, NETHERLANDS SP MESA+, Analyt Chem, Microcosm, Jenoptik, Hewlett Packard, 3T, Cepheid, Twente MicroProd, Univ Twente DE ChEC; monolith; capillary electrochromatography ID CAPILLARY ELECTROCHROMATOGRAPHY; POLYMER MONOLITHS; CHROMATOGRAPHY; PERFORMANCE; MICROCHIP; MEDIA AB We describe the first use of a UV-initiated porous polymer monolith (PPM) in a microfabricated electrochromatographic separation device. Porous polymer monoliths have several characteristics that make them particularly attractive as a stationary phase for chip electrochromatography (ChEC). The PPM requires no frits, is easily introduced into the system prior to polymerization, and is photopatternable. Relevant ChEC properties such as charge polarity, charge density, hydrophobicity, and porosity are controlled by adjusting the composition of the polymer precursor solution. A zwitterionic fluorescent dye, Rhodamine 610 (R610), was used to image injections at the T with a fluorescence microscope. A "pinched" injection was achieved by actively controlling the voltage at all four reservoirs throughout the injection and separation modes. A CEC separation of explosives on the PPM in a capillary resolved twelve of fourteen components, giving efficiencies of 295,000 plates/m. A ChEC separation of Cy-5 dye from observed fluorescent impurities was successful. Analytes were detected by laser induced fluorescence at 650 nm on the PPM. These results are compared to a separation of the Cy-5 by capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC). Buffer and solvent could be changed rapidly by using either pressure or electroosmotic flow. These results demonstrate the feasibility of the PPM as a solid phase for electroosmotic flow-driven chip-based chromatography in mu TAS. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Fintschenko, Y (reprint author), Sandia Natl Labs, POB 969,MS9671, Livermore, CA 94551 USA. NR 8 TC 0 Z9 0 U1 0 U2 2 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6387-6 J9 MESA MG PY 2000 BP 411 EP 414 PG 4 WC Biotechnology & Applied Microbiology; Chemistry, Analytical; Engineering, Mechanical; Instruments & Instrumentation SC Biotechnology & Applied Microbiology; Chemistry; Engineering; Instruments & Instrumentation GA BR72M UT WOS:000167335400096 ER PT B AU Lemoff, AV Lee, AP AF Lemoff, AV Lee, AP BE VandenBerg, A Bergveld, P Olthuis, W TI An AC magnetohydrodynamic microfluidic switch SO MICRO TOTAL ANALYSIS SYSTEMS 2000, PROCEEDINGS SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000) CY MAY 14-18, 2000 CL ENSCHEDE, NETHERLANDS SP MESA+, Analyt Chem, Microcosm, Jenoptik, Hewlett Packard, 3T, Cepheid, Twente MicroProd, Univ Twente DE magnetohydrodynamic; fluidic switch; Lorentz force; micropump AB A microfluidic switch has been demonstrated using an AC Magnetohydrodynamic (MHD) pumping mechanism in which the Lorentz force is used to pump an electrolytic solution. By integrating two AC MHD pumps into different arms of a Y-shaped fluidic circuit, flow can be switched between the two arms. This type of switch can be used to produce complex fluidic routing, which may have multiple applications in mu TAS. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Microtechnol, Livermore, CA 94550 USA. RP Lemoff, AV (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Microtechnol, 7000 East Ave,L-223, Livermore, CA 94550 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6387-6 J9 MESA MG PY 2000 BP 571 EP 574 PG 4 WC Biotechnology & Applied Microbiology; Chemistry, Analytical; Engineering, Mechanical; Instruments & Instrumentation SC Biotechnology & Applied Microbiology; Chemistry; Engineering; Instruments & Instrumentation GA BR72M UT WOS:000167335400134 ER PT B AU Paul, PH Arnold, DW Neyer, DW Smith, KB AF Paul, PH Arnold, DW Neyer, DW Smith, KB BE VandenBerg, A Bergveld, P Olthuis, W TI Electrokinetic pump application in micro-total analysis systems mechanical actuation to HPLC SO MICRO TOTAL ANALYSIS SYSTEMS 2000, PROCEEDINGS SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000) CY MAY 14-18, 2000 CL ENSCHEDE, NETHERLANDS SP MESA+, Analyt Chem, Microcosm, Jenoptik, Hewlett Packard, 3T, Cepheid, Twente MicroProd, Univ Twente DE electrokinetic pump; porous media; HPLC ID POROUS-MEDIA; PERMEABILITY; TRANSPORT; ELECTROPHORESIS; CONDUCTIVITY AB Electrokinetic pumping in microporous media provides a means to integrate flow and high pressure generating capability in mu TAS. A general formalism describing flow and current transport in porous media is presented. This is applied to the design of a complete electrokinetic pump-driven HPLC system that is suitable for full chip-scale integration. The application of the electrokinetic pump as a driver for mechanical actuation is also considered. A model and experimental results for the frequency response of an electrokinetic pump are presented. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Paul, PH (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 14 TC 21 Z9 21 U1 2 U2 6 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6387-6 J9 MESA MG PY 2000 BP 583 EP 590 PG 8 WC Biotechnology & Applied Microbiology; Chemistry, Analytical; Engineering, Mechanical; Instruments & Instrumentation SC Biotechnology & Applied Microbiology; Chemistry; Engineering; Instruments & Instrumentation GA BR72M UT WOS:000167335400137 ER PT B AU Paul, PH Arnold, DW Rakestraw, DJ AF Paul, PH Arnold, DW Rakestraw, DJ BE Harrison, DJ VanDenBerg, A TI Electrokinetic generation of high pressures using porous microstructures SO MICRO TOTAL ANALYSIS SYSTEMS '98 SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 3rd International Symposium on Micro-Total Analysis Systems (mu-TAS'98) CY OCT 13-16, 1998 CL BANFF, CANADA DE electrokinetic; micropump AB The ability to generate high pressures using electrokinetic pumping of liquid through porous media is reported. Pressures in excess of 8000 psi have been achieved using silica capillaries packed with micron-size silica beads. A model is presented which captures absolute pressures, flowrates and power conversion efficiencies as well as the experimentally observed dependencies on pore size, applied electric field and electrical properties of the fluid. This previously unrecognized phenomena offers the possibility of creating a new class on micro-and meso-scale fluid devices where electroosmotic flow in a fine porous media is used as a pump to impart net useful hydraulic power to the fluid. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Paul, PH (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 5 TC 1 Z9 1 U1 4 U2 5 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5322-6 J9 MESA MG PY 2000 BP 49 EP 52 PG 4 WC Chemistry, Analytical; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Chemistry; Engineering; Instruments & Instrumentation GA BP68E UT WOS:000085854700011 ER PT B AU Ermakov, SV Jacobson, SC Ramsey, JM AF Ermakov, SV Jacobson, SC Ramsey, JM BE Harrison, DJ VanDenBerg, A TI Computer simulations for microchip electrophoresis SO MICRO TOTAL ANALYSIS SYSTEMS '98 SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 3rd International Symposium on Micro-Total Analysis Systems (mu-TAS'98) CY OCT 13-16, 1998 CL BANFF, CANADA DE simulation; mass transport; gated injection; pinched injection ID CAPILLARY ELECTROPHORESIS; CHIPS AB A mathematical model describing electrokinetically driven mass transport phenomena in microfabricated chip devices is presented. The model accounts for principal material transport mechanisms including electrokinetic migration (electrophoresis and electroosmosis) and diffusion. A computer code that implements the model is capable of simulating the mass transport during electrokinetic manipulation in any 2-D channel structures. The code allows arbitrary channel geometries with various boundary conditions for the electric field and the sample concentration. The results simulating the sample mass transport in a cross channel geometry during different types of electrokinetic injection are presented. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ermakov, SV (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 11 TC 0 Z9 0 U1 1 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5322-6 J9 MESA MG PY 2000 BP 149 EP 152 PG 4 WC Chemistry, Analytical; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Chemistry; Engineering; Instruments & Instrumentation GA BP68E UT WOS:000085854700036 ER PT B AU Culbertson, CT Jacobson, SC Ramsey, JM AF Culbertson, CT Jacobson, SC Ramsey, JM BE Harrison, DJ VanDenBerg, A TI Minimizing dispersion introduced by turns on microchips SO MICRO TOTAL ANALYSIS SYSTEMS '98 SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 3rd International Symposium on Micro-Total Analysis Systems (mu-TAS'98) CY OCT 13-16, 1998 CL BANFF, CANADA DE band broadening; dispersion; turns; corners; DNA separations ID ELECTROPHORESIS; SYSTEMS; DEVICES AB For electrophoretic separations on microchip devices the introduction of turns into the separation channel often creates a geometrical contribution to analyte dispersion in addition to the dispersion generated from analyte diffusion and the injection plug length. We have developed a one-dimensional model which predicts the amount of geometrical dispersion introduced by turns. This model accounts for the migration length and field strength differences experienced by the individual molecules in the analyte band as they traverse the turn. It also accounts for the effects of transverse diffusion which occurs across the width of the channel as the analyte band migrates through the rum. The model describes the experimental data well. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Culbertson, CT (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5322-6 J9 MESA MG PY 2000 BP 161 EP 164 PG 4 WC Chemistry, Analytical; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Chemistry; Engineering; Instruments & Instrumentation GA BP68E UT WOS:000085854700039 ER PT B AU Jacobson, SC Kutter, JP Culbertson, CT Ramsey, JM AF Jacobson, SC Kutter, JP Culbertson, CT Ramsey, JM BE Harrison, DJ VanDenBerg, A TI Rapid electrophoretic and chromatographic analysis on microchips SO MICRO TOTAL ANALYSIS SYSTEMS '98 SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 3rd International Symposium on Micro-Total Analysis Systems (mu-TAS'98) CY OCT 13-16, 1998 CL BANFF, CANADA DE microchip; electrophoresis; chromatography ID CAPILLARY ELECTROPHORESIS; POSTCOLUMN REACTOR; SILICON CHIP; GLASS CHIPS; SEPARATIONS; DEVICE AB Rapid, high-performance electrokinetically-driven separations are easily incorporated into microfabricated devices. The first example is an electrophoretic separation of a binary mixture that was completed in less than 1 millisecond. A separation field strength of 53 kV cm(-1) was used (8.6 kV applied to the microchip), and the separation was monitored 200 mu m downstream from the injection valve. The second separation technique described is solvent-programmed open-channel electrochromatography. Using a microchip with its channel walls coated with a C-18 stationary phase and applying a five second, linear gradient, a sample of coumarin dyes was resolved in just under 20 seconds. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Jacobson, SC (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 15 TC 0 Z9 0 U1 1 U2 2 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5322-6 J9 MESA MG PY 2000 BP 315 EP 318 PG 4 WC Chemistry, Analytical; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Chemistry; Engineering; Instruments & Instrumentation GA BP68E UT WOS:000085854700074 ER PT B AU Lin, YH Xu, NX Wen, J Matson, D Smith, RD AF Lin, YH Xu, NX Wen, J Matson, D Smith, RD BE Harrison, DJ VanDenBerg, A TI Microfabricated dual-microdialysis and capillary isoelectric focusing devices for cleanup and separations/mass spectrometric analysis of biomolecules SO MICRO TOTAL ANALYSIS SYSTEMS '98 SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 3rd International Symposium on Micro-Total Analysis Systems (mu-TAS'98) CY OCT 13-16, 1998 CL BANFF, CANADA DE microdialysis; electrospray ionization mass spectrometry; capillary isoelectric focusing; protein ID ELECTROSPRAY AB A laser microfabricated device was constructed for rapid on-line microdialysis cleanup of biological samples for analysis by electrospray ionization mass spectrometry (ESI-MS). Efficient desalting was achieved for protein samples using ESI with an ion trap mass spectrometer. Signal-to noise ratios were greatly enhanced compared to direct infusion of the original nondialyzed samples. Microfabricated capillary isoelectric focusing (CIEF) devices were also constructed and successful separations of various protein samples with the CIEF chip were demonstrated. 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; Smith, Richard/J-3664-2012 OI Lin, Yuehe/0000-0003-3791-7587; Smith, Richard/0000-0002-2381-2349 NR 3 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5322-6 J9 MESA MG PY 2000 BP 343 EP 346 PG 4 WC Chemistry, Analytical; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Chemistry; Engineering; Instruments & Instrumentation GA BP68E UT WOS:000085854700081 ER PT B AU Matson, DW Martin, PM Bennett, WD Kurath, DE Lin, YH Hammerstrom, DJ AF Matson, DW Martin, PM Bennett, WD Kurath, DE Lin, YH Hammerstrom, DJ BE Harrison, DJ VanDenBerg, A TI Fabrication processes for polymer-based microfluidic analytical devices SO MICRO TOTAL ANALYSIS SYSTEMS '98 SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 3rd International Symposium on Micro-Total Analysis Systems (mu-TAS'98) CY OCT 13-16, 1998 CL BANFF, CANADA DE microchannel; polymer; microanalytical; dialysis; electrospray; laser AB Fabrication methods for polymer-based microanalytical devices are described. Production of microchannels is based on laser micromachining methods, and are produced either by directly milling channels into substrate faces, or by sandwiching thin pieces of machined polyimide between solid surfaces. Use of a multilayer laminated process for some of the devices improves device compactness and efficiency of fluid flow. C1 Pacific NW Labs, Richland, WA 99352 USA. RP Matson, DW (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 2 TC 1 Z9 1 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5322-6 J9 MESA MG PY 2000 BP 371 EP 374 PG 4 WC Chemistry, Analytical; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Chemistry; Engineering; Instruments & Instrumentation GA BP68E UT WOS:000085854700088 ER PT B AU Arnold, DW Bailey, CG Garguilo, MG Matzke, CM Wendt, JR Sweatt, WC Kravitz, SH Warren, ME Rakestraw, DJ AF Arnold, DW Bailey, CG Garguilo, MG Matzke, CM Wendt, JR Sweatt, WC Kravitz, SH Warren, ME Rakestraw, DJ BE Harrison, DJ VanDenBerg, A TI Microseparations and microfluidic studies SO MICRO TOTAL ANALYSIS SYSTEMS '98 SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 3rd International Symposium on Micro-Total Analysis Systems (mu-TAS'98) CY OCT 13-16, 1998 CL BANFF, CANADA DE microsystem; integration; microoptics; chromatograph ID SYSTEMS AB Microscale integrated chemical analysis systems have been fabricated which employ electrokinetic chromatography with laser-induced fluorescence detection. The microoptical systems utilize vertical cavity surface emitting diode lasers (VCSELs),: diffractive lenses, microreflectors and diode detectors. The flow channels and diffractive optics have been fabricated in fused silica and the VCSELs are attached to the substrates using flip-chip bonding. The electrokinetic separations make use of micellar separations in open channels and reverse phase separations that use both bead-packed microchannels and lithographically-patterned stationary phase supports. The detailed flow characteristics of these systems is visualized using novel imaging methods. C1 Sandia Natl Labs, Chem & Radiat Lab, Livermore, CA 94550 USA. RP Arnold, DW (reprint author), Sandia Natl Labs, Chem & Radiat Lab, Livermore, CA 94550 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5322-6 J9 MESA MG PY 2000 BP 435 EP 438 PG 4 WC Chemistry, Analytical; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Chemistry; Engineering; Instruments & Instrumentation GA BP68E UT WOS:000085854700104 ER PT B AU Frye-Mason, GC Kottenstette, RJ Heller, EJ Matzke, CM Casalnuovo, SA Lewis, PR Manginell, RP Schubert, WK Hietala, VM Shul, RJ AF Frye-Mason, GC Kottenstette, RJ Heller, EJ Matzke, CM Casalnuovo, SA Lewis, PR Manginell, RP Schubert, WK Hietala, VM Shul, RJ BE Harrison, DJ VanDenBerg, A TI Integrated chemical analysis systems for gas phase CW agent detection SO MICRO TOTAL ANALYSIS SYSTEMS '98 SE MESA MONOGRAPHS LA English DT Proceedings Paper CT 3rd International Symposium on Micro-Total Analysis Systems (mu-TAS'98) CY OCT 13-16, 1998 CL BANFF, CANADA DE gas chromatograph; GC; surface acoustic wave; SAW AB A miniature, integrated chemical laboratory (mu ChemLab) is being developed that utilizes microfabrication to provide faster response, smaller size, and an ability to:utilize multiple analysis channels for enhanced versatility acid chemical discrimination.: Improved sensitivity and selectivity are achieved by using a cascaded approach where each channel includes a sample collector/concentrator, a gas chromatographic (GC) separator.:and a chemically selective surface acoustic wave (SAW) array detector. Prototypes of all three components have been developed and demonstrated individually and current work is focused on integrating these into a complete analysis system. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Frye-Mason, GC (reprint author), Sandia Natl Labs, POB 5800,MS-1425, Albuquerque, NM 87185 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5322-6 J9 MESA MG PY 2000 BP 477 EP 481 PG 5 WC Chemistry, Analytical; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Chemistry; Engineering; Instruments & Instrumentation GA BP68E UT WOS:000085854700113 ER PT S AU Romig, AD Michael, JR Michalske, TA AF Romig, AD Michael, JR Michalske, TA BE Williams, DB Shimizu, R TI Nanotechnology: promises and challenges for tomorrow SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Romig, AD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 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 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 3 EP 4 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400002 ER PT S AU Havrilla, GJ Schoonover, JR AF Havrilla, GJ Schoonover, JR BE Williams, DB Shimizu, R TI Integrated Spectroscopic Imaging: applications using micro X-ray fluorescence, micro Raman and micro infrared SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Havrilla, GJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 35 EP 36 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400018 ER PT S AU Carr, GL Ramotowski, M Miller, LM AF Carr, GL Ramotowski, M Miller, LM BE Williams, DB Shimizu, R TI Resolution limits for scanning infrared microspectroscopy: theory and practice SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc ID SYNCHROTRON-RADIATION; PERFORMANCE C1 Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Carr, GL (reprint author), Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. NR 3 TC 2 Z9 2 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 51 EP 52 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400026 ER PT S AU Miller, LM Dumas, P Jamin, N Teillaud, JL Bantignies, JL Carr, GL AF Miller, LM Dumas, P Jamin, N Teillaud, JL Bantignies, JL Carr, GL BE Williams, DB Shimizu, R TI Applications of synchrotron infrared microspectroscopy to the study of biological cells and tissues SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. Ctr Univ Paris Sud, LURE, F-91898 Orsay, France. CEA, INSTN, CIE, F-91191 Gif Sur Yvette, France. Inst Curie, INSERM, U255, F-75248 Paris 05, France. RP Miller, LM (reprint author), Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. NR 4 TC 4 Z9 4 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 75 EP 76 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400038 ER PT S AU Goehner, RP Tissot, RG Michael, JR AF Goehner, RP Tissot, RG Michael, JR BE Williams, DB Shimizu, R TI Small area analysis using micro-diffraction techniques SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Goehner, RP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 133 EP 134 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400067 ER PT S AU Carpenter, DA AF Carpenter, DA BE Williams, DB Shimizu, R TI XRMF with capillary optics and low-power micro-focus source SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc ID RAY C1 Oak Ridge Y12 Plant, Oak Ridge, TN 37831 USA. RP Carpenter, DA (reprint author), Oak Ridge Y12 Plant, Box 2009, Oak Ridge, TN 37831 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 135 EP 136 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400068 ER PT S AU Keast, VJ Kung, H Misra, A Mitchell, TE AF Keast, VJ Kung, H Misra, A Mitchell, TE BE Williams, DB Shimizu, R TI Compositional mapping of nanolayered metal composites SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HI SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Univ Cambridge, Dept Mat Sci & Met, Cambridge CB2 3QZ, England. Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87544 USA. RP Keast, VJ (reprint author), Univ Cambridge, Dept Mat Sci & Met, Pembroke St, Cambridge CB2 3QZ, England. RI Misra, Amit/H-1087-2012 NR 3 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 145 EP 146 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400073 ER PT S AU Kotula, PG Keenan, MR AF Kotula, PG Keenan, MR BE Williams, DB Shimizu, R TI Automated unbiased information extraction of STEM-EDS spectrum images SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc ID MULTIVARIATE C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Kotula, PG (reprint author), Sandia Natl Labs, Mail Stop 1405,POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 147 EP 148 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400074 ER PT S AU Burke, MG Miller, MK AF Burke, MG Miller, MK BE Williams, DB Shimizu, R TI The application of AEM and APFIM to the analysis of precipitation behavior in Alloy 718 SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Burke, MG (reprint author), Bechtel Bettis Inc, W Mifflin, PA 15122 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 161 EP 162 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400081 ER PT S AU Michael, JR Goehner, RP AF Michael, JR Goehner, RP BE Williams, DB Shimizu, R TI Ab-initio primitive cell calculations from EBSD patterns SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Michael, JR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 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 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 203 EP 204 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400102 ER PT S AU Carpenter, DA Bullock, JS AF Carpenter, DA Bullock, JS BE Williams, DB Shimizu, R TI OIM and EDX determination of the orientation dependence of corrosion in uranium metal SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Oak Ridge Y12 Plant, Oak Ridge, TN 37831 USA. RP Carpenter, DA (reprint author), Oak Ridge Y12 Plant, Box 2009, Oak Ridge, TN 37831 USA. NR 0 TC 0 Z9 0 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 209 EP 210 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400105 ER PT S AU Bentley, J AF Bentley, J BE Williams, DB Shimizu, R TI Quantitative composition mapping by EFTEM SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Bentley, J (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 229 EP 230 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400115 ER PT S AU Grogger, W del Arco, MV Ballesteros, C Krishnan, K AF Grogger, W del Arco, MV Ballesteros, C Krishnan, K BE Williams, DB Shimizu, R TI Energy-filtered imaging and growth mechanism of YBa2Cu3O7-delta ultrathin films SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Dept Mat Sci, Berkeley, CA 94720 USA. Univ Carlos III Leganes, Dept Fis, Madrid 28911, Spain. RP Grogger, W (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Dept Mat Sci, Berkeley, CA 94720 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 231 EP 232 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400116 ER PT S AU Pennycook, SJ Rafferty, B Duscher, G AF Pennycook, SJ Rafferty, B Duscher, G BE Williams, DB Shimizu, R TI Towards single atom column EELS in an aberration-corrected STEM SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc ID SPECTROSCOPY C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RP Pennycook, SJ (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Duscher, Gerd/G-1730-2014 OI Duscher, Gerd/0000-0002-2039-548X 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 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 243 EP 244 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400122 ER PT S AU Frost, BG Joy, DC AF Frost, BG Joy, DC BE Williams, DB Shimizu, R TI Off-axis electron holography of field emission nanotips SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Univ Tennessee, Sci & Engn Res Ctr 232, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Frost, BG (reprint author), Univ Tennessee, Sci & Engn Res Ctr 232, Knoxville, TN 37996 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 257 EP 258 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400129 ER PT S AU Joy, DC Braski, D AF Joy, DC Braski, D BE Williams, DB Shimizu, R TI Secondary electron spectroscopy SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, EM Facil, Knoxville, TN 37996 USA. RP Joy, DC (reprint author), Univ Tennessee, EM Facil, Knoxville, TN 37996 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 261 EP 262 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400131 ER PT S AU Ko, YU Hwu, JJ Joy, DC AF Ko, YU Hwu, JJ Joy, DC BE Williams, DB Shimizu, R TI Monte Carlo model of charging in resists in e-beam lithography and metrology SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc ID LINEWIDTH METROLOGY; SIMULATION C1 Univ Tennessee, EM Facil, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37813 USA. RP Ko, YU (reprint author), Univ Tennessee, EM Facil, Knoxville, TN 37996 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 283 EP 284 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400142 ER PT S AU Small, JA Michael, JR Newbury, DE AF Small, JA Michael, JR Newbury, DE BE Williams, DB Shimizu, R TI Improving the accuracy of particle analysis SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Small, JA (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 1 TC 0 Z9 0 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 305 EP 306 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400153 ER PT S AU Houston, JE AF Houston, JE BE Williams, DB Shimizu, R TI Studies of the nanomechanical properties of Au thin films by interfacial force microscopy SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc ID SCALE; GOLD C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Houston, JE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 365 EP 366 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400183 ER PT S AU Carpenter, P Counce, D Kluk, E Nabelek, C AF Carpenter, P Counce, D Kluk, E Nabelek, C BE Williams, DB Shimizu, R TI Characterization of Corning standard glasses 95IRV, 95IRW, and 95IRX, by ICP-AES, XRF, and EPMA SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc, Alliance Micrograv Mat Sci & Applicat, Huntsville, AL 35812 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Missouri, Dept Geol Sci, Columbia, MO 65211 USA. RP Carpenter, P (reprint author), NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc, Alliance Micrograv Mat Sci & Applicat, SD47, Huntsville, AL 35812 USA. NR 1 TC 2 Z9 2 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 401 EP 402 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400201 ER PT S AU Anderson, IM AF Anderson, IM BE Williams, DB Shimizu, R TI Spectrum imaging: the future of quantitative X-ray mapping? SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Anderson, IM (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 9 TC 1 Z9 1 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 437 EP 438 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400219 ER PT S AU More, KL Tortorelli, PF Walker, LR AF More, KL Tortorelli, PF Walker, LR BE Williams, DB Shimizu, R TI Evaluating the stability of BN interfacial coatings in SiC/SiC composites exposed to oxygen- and H2O-containing environments SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc ID WATER-VAPOR; OXIDATION C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP More, KL (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RI More, Karren/A-8097-2016 OI More, Karren/0000-0001-5223-9097 NR 4 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 473 EP 474 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400237 ER PT S AU Hwu, JJ Ko, Y Joy, DC AF Hwu, JJ Ko, Y Joy, DC BE Williams, DB Shimizu, R TI Modeling of electron beam deflection from charging in electron beam lithography SO MICROBEAM ANALYSIS 2000, PROCEEDINGS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 2nd Conference of the International-Union-of-Microbeam-Analysis-Societies CY JUL 09-14, 2000 CL KAILUA KONA, HAWAII SP Australian Microbeam Anal Soc, Brasilian Soc Microscopy & Microanal, Microscopy Soc Canada, China Joint Comm Microbeam Anal, European Microbeam Anal Soc, Japan Soc Promot Sci, Comm 141 Microbeam Anal, Korean Soc Electron Microscopy, Microbeam Anal Soc C1 Univ Tennessee, Electron Microscope Facil, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hwu, JJ (reprint author), Univ Tennessee, Electron Microscope Facil, Knoxville, TN 37996 USA. NR 6 TC 0 Z9 0 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0685-8 J9 INST PHYS CONF SER PY 2000 IS 165 BP 479 EP 480 PG 2 WC Instruments & Instrumentation; Microscopy; Physics, Multidisciplinary; Spectroscopy SC Instruments & Instrumentation; Microscopy; Physics; Spectroscopy GA BR57H UT WOS:000166835400240 ER PT J AU Fleetwood, DM Winokur, PS Dodd, PE AF Fleetwood, DM Winokur, PS Dodd, PE TI An overview of radiation effects on electronics in the space telecommunications environment SO MICROELECTRONICS RELIABILITY LA English DT Article ID SINGLE-EVENT UPSET; BIPOLAR JUNCTION TRANSISTORS; LOW-DOSE-RATES; HARDNESS-ASSURANCE; IN-SPACE; INTEGRATED-CIRCUITS; IONIZING-RADIATION; GAIN DEGRADATION; ENHANCED DAMAGE; INDUCED LATCHUP AB Trapped protons and electrons in the Earth's radiation belts and cosmic rays present significant challenges for electronics that must operate reliably in the natural space environment. Single event effects (SEE) can lead to sudden device or system failure, and total dose effects can reduce the lifetime of a space-based telecommunications system. One of the greatest sources of uncertainty in developing radiation requirements for a space system is accounting for the small but finite probability that the system will be exposed to a massive solar particle event, Once specifications are decided, standard laboratory tests are available to predict the total dose response of MOS and bipolar components in space, but SEE testing of components can be more challenging, Prospects are discussed for device modeling, and for the use of commercial electronics in space. In addition: technology trends are discussed for the radiation response of microelectronics in space. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Vanderbilt Univ, EEC Dept, Nashville, TN 37235 USA. Sandia Natl Labs, Radiat Technol & Assurance Dept, Albuquerque, NM 87185 USA. RP Fleetwood, DM (reprint author), Vanderbilt Univ, EEC Dept, Stn B,POB 92, Nashville, TN 37235 USA. EM dan.fleetwood@vanderbilt.edu NR 102 TC 36 Z9 37 U1 0 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0026-2714 J9 MICROELECTRON RELIAB JI Microelectron. Reliab. PD JAN PY 2000 VL 40 IS 1 BP 17 EP 26 DI 10.1016/S0026-2714(99)00225-5 PG 10 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 277CR UT WOS:000084915600003 ER PT S AU Cummings, EB Singh, AK AF Cummings, EB Singh, AK BE Mastrangelo, CH Becker, H TI Dielectrophoretic trapping without embedded electrodes SO MICROFLUIDIC DEVICES AND SYSTEMS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Microfluidic Devices and Systems III CY SEP 18-19, 2000 CL SANTA CLARA, CA SP SPIE, Semicond Equipment & Mat Int, Solid State Technol, Sandia Natl Lab DE dielectrophoresis; electroosmosis; electrophoresis; electrokinetic flow; patterned bed; microarrays; trapping; latex microspheres; microfluidics; separations ID SEPARATION; CELLS AB We observe dielectrophoretic effects in mixed electrokinetic and dielectrophoretic flows in uniform arrays of posts. Above a threshold applied electric field, flowing filaments of concentrated and rarefied particles appear in the flow. Above a higher-threshold applied field, zones of highly concentrated, immobilized particles appear. At the lower and higher thresholds, dielectrophoresis apparently begins to dominate diffusion and advection/electrokinesis, respectively. The patterns of filaments and trapped zones depend dramatically on the angle of the array with respect to the mean applied electric field and the shape of the posts in the array. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Cummings, EB (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94550 USA. RI Sano, Michael/E-1715-2011 NR 12 TC 29 Z9 29 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 0-8194-3833-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4177 BP 164 EP 173 PG 10 WC Chemistry, Analytical; Engineering, Electrical & Electronic; Materials Science, Coatings & Films; Optics; Physics, Condensed Matter SC Chemistry; Engineering; Materials Science; Optics; Physics GA BR15D UT WOS:000165735100019 ER PT S AU Galambos, P Benavides, G AF Galambos, P Benavides, G BE Mastrangelo, CH Becker, H TI Electrical and fluidic packaging of surface micromachined electro-microfluidic devices SO MICROFLUIDIC DEVICES AND SYSTEMS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Microfluidic Devices and Systems III CY SEP 18-19, 2000 CL SANTA CLARA, CA SP SPIE, Semicond Equipment & Mat Int, Solid State Technol, Sandia Natl Lab DE microfluidics; packaging; electro-microfluidic interconnection; MEMS AB Microfluidic devices have applications in chemical analysis, biomedical devices and ink-jets'. An integrated microfluidic system incorporates electrical signals on-chip. Such electro-microfluidic devices require fluidic and electrical connection to larger packages. Therefore electrical and fluidic packaging of electro-microfluidic devices is key to the development of integrated microfluidic systems. Packaging is more challenging for surface micromachined devices than for larger bulk micromachined devices. However, because surface micromachining allows incorporation of electrical traces during microfluidic channel fabrication, a monolithic device results. A new architecture for packaging surface micromachined electro-microfluidic devices is presented. This architecture relies on two scales of packaging to bring fluid to the device scale (picoliters) from the macroscale(microliters). The architecture emulates and utilizes electronics packaging technology. The larger package consists of a circuit board with embedded fluidic channels and standard fluidic connectors. The embedded channels connect to the smaller package, an Electro-Microfluidic Dual-Inline-Package (EMDIP) that takes fluid to the microfluidic integrated circuit (MIC). The fluidic connection is made to the back of the MIC through Bosch(2) etched holes that take fluid to surface micromachined channels on the front of the MIG. Electrical connection is made to bond pads on the front of the MIG. 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 12 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 0-8194-3833-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4177 BP 200 EP 207 PG 8 WC Chemistry, Analytical; Engineering, Electrical & Electronic; Materials Science, Coatings & Films; Optics; Physics, Condensed Matter SC Chemistry; Engineering; Materials Science; Optics; Physics GA BR15D UT WOS:000165735100023 ER PT S AU Griffiths, SK Nilson, RH AF Griffiths, SK Nilson, RH BE Mastrangelo, CH Becker, H TI Dispersion in turns for species transport by electrophoresis and electroosmotic flow SO MICROFLUIDIC DEVICES AND SYSTEMS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Microfluidic Devices and Systems III CY SEP 18-19, 2000 CL SANTA CLARA, CA SP SPIE, Semicond Equipment & Mat Int, Solid State Technol, Sandia Natl Lab DE dispersion; microchannel; turn; electrokinetic; electroosmotic; electrophoretic ID MICELLAR ELECTROKINETIC CHROMATOGRAPHY; OPEN-CHANNEL ELECTROCHROMATOGRAPHY; CAPILLARY LIQUID-CHROMATOGRAPHY; MICROCHIP; SEPARATIONS; CHIPS; DNA; SYSTEMS; GLASS; TECHNOLOGY AB Analytical and numerical methods are employed to investigate species transport by electrophoretic or electroosmotic motion in the curved geometry of a two-dimensional turn. Closed-form analytical solutions describing the turn-induced diffusive and dispersive spreading of a species band are presented for both the low and high Peclet number limits. We find that the spreading due to dispersion is proportional to the product of the turn included angle and the Peclet number at low Peclet numbers. It is proportional to the square of the included angle and independent of the Peclet number when the Peclet number is large. A composite solution applicable to all Peclet numbers is constructed from these limiting behaviors. Numerical solutions for species transport in a turn are also presented over a wide range of the included angle and the mean turn radius. Based on comparisons between the analytical and numerical results, we find that the analytical solutions provide very good estimates of both dispersive and diffusive spreading provided that the mean turn radius exceeds the channel width. These new solutions also agree well with data from a previous study. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Griffiths, SK (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. NR 39 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 0-8194-3833-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4177 BP 229 EP 240 PG 12 WC Chemistry, Analytical; Engineering, Electrical & Electronic; Materials Science, Coatings & Films; Optics; Physics, Condensed Matter SC Chemistry; Engineering; Materials Science; Optics; Physics GA BR15D UT WOS:000165735100027 ER PT S AU Nilson, RH Griffiths, SK AF Nilson, RH Griffiths, SK BE Karam, JM Yasaitis, J TI Acoustic agitation for enhanced development of LIGA PMMA resists SO MICROMACHINING AND MICROFABRICATION PROCESS TECHNOLOGY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Micromachining and Microfabrication Process Technology VI CY SEP 18-19, 2000 CL SANTA CLARA, CA SP SPIE, SolidState Technol, Sandia Natl Lab, Semicond Equipment & Mat Int DE LIGA; development; transport; ultrasonic; sonic agitation; acoustic streaming; microstructures ID MICROSTRUCTURES; FABRICATION AB The development of exposed PMMA resists for the LIGA process is very difficult and time-consuming when the resist thickness is large (similar to1 mm) and feature aspect ratios exceed about four. This is due mainly to limitations on the development rate imposed by the diffusive transport of PMMA fragments away from the dissolution surface. Development rates under these conditions can be enhanced significantly by high-frequency acoustic agitation. To study this enhancement, analytical solutions describing the periodic flow field are used to evaluate the time-mean Reynolds stresses that drive streaming fluid motion. The resulting steady flow and transport rates within a feature are then computed by solving the Navier Stokes and species transport equations. For typical acoustic frequencies and power levels of 1 MHz and 6 w/cm(2) the streaming flow within the feature is torroidal, with inflow along the feature walls at maximum speeds approaching 1 mm/min, coupled with a slower Outflow along the feature center. The computed increase in transport, relative to diffusion, is typically on the order of 4 to 6 for feature aspect ratios ranging from 3 to 10 and for polymer fragment diffusivities on the order of 10(-11) m(2)/s, provided that the feature width is greater than about 10 microns. In smaller features, the streaming speed may be suppressed by overlapping viscous boundary layers on opposing feature walls. Higher frequencies help reduce the boundary layer thickness but may lead to less efficient multi-cellular flow patterns when the acoustic wavelength (similar to1 mm at 1MHz) is less than the feature depth. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Nilson, RH (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. NR 12 TC 3 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 0-8194-3830-8 J9 P SOC PHOTO-OPT INS PY 2000 VL 4174 BP 66 EP 76 DI 10.1117/12.396462 PG 11 WC Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Coatings & Films; Optics; Physics, Applied SC Electrochemistry; Engineering; Materials Science; Optics; Physics GA BR15B UT WOS:000165734900008 ER PT B AU Sweeney, D AF Sweeney, D GP JSAP JSAP JSAP JSAP TI Current status of EUV optics and future advancements in optical components SO MICROPROCESSES AND NANOTECHNOLOGY 2000, DIGEST OF PAPERS LA English DT Proceedings Paper CT International Microprocesses and Nanotechnology Conference CY JUL 11-13, 2000 CL UNIV TOKYO, KOMABA CAMPUS, TOKYO, JAPAN SP Japan Soc Appl Phys, IEEE, Electr Devices Soc, Amer Vacuum Soc, Assoc Super Adv Electr Technol, Inst Elect Engineers Japan, Inst Electr, Informat & Commun Engineers, Japanese Soc Synchrotron Radiat Res, Japanese Soc Electron Microscopy, Surface Sci Soc Japan, Vacuum Soc Japan HO UNIV TOKYO, KOMABA CAMPUS C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Sweeney, D (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BUSINESS CENTER ACADEMIC SOC JAPAN PI TOKYO PA 5-16-9, HONKOMAGOME, 5-CHOME, BUNKYO-KU, TOKYO, 113-8622, JAPAN BN 4-89114-004-6 PY 2000 BP 280 EP 281 DI 10.1109/IMNC.2000.872763 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR55L UT WOS:000166793600137 ER PT B AU Wegeng, RS Drost, MK Brenchley, DL AF Wegeng, RS Drost, MK Brenchley, DL BE Ehrfeld, W TI Process intensification through miniaturization of chemical and thermal systems in the 21(st) century SO MICROREACTION TECHNOLOGY: INDUSTRIAL PROSPECTS LA English DT Proceedings Paper CT 3rd International Conference on Microreaction Technology CY APR 18-21, 1999 CL NEW ORLEANS, LA SP Battle Memor Inst, Amer Inst Chem Engineers, Soc Chem Engn & Biotechnol, Inst Microtechnol Mainz DE miniaturization; microscale systems; reactors; heat pumps AB The 21(st) century holds great promise for development of Micro Chemical and Thermal Systems (MICRO-CATS(TM)). The quest for miniaturization will lead to greater process intensification. Miniaturization greatly reduces the resistances to heat and mass transfer. When heat and mass transfer rates are increased by orders of magnitude, revolutionary changes occur in technology. Miniaturization of electronics over the past few decades has transformed the way we live. The invention of the transistor meant that small, lightweight portable radios could be carried anywhere. Not long ago the idea of chips was revolutionary; today chips make hand-held computers, cell phones, and many other hand-held electrical devices possible. These are examples of distributed technology made possible by miniaturization. Miniaturization of chemical and thermal systems will take us on a similar technological journey. Already demands are driving the development of MICRO-CATS. The quest for miniature systems is leading to man-portable cooling, automotive fuel processing, and in situ resource utilization for space exploration. The 21(st) century will see great progress in the development and use of engineered nanosystems. In electronics, the concept of "molecular electronics" is seen as a way to further increase the power. The same will occur in MICRO-CATS. We envision using engineered nanosystems to create more powerful microscale devices with highly functional surfaces that incorporate enzymes and chemical catalysts. These surfaces will make the device or system more efficient and reliable; they will be able to repair, renew, or replace themselves; eliminate or heal themselves from surface fouling; and carry out step-by-step chemical reactions. Molecular coatings will create a molecular assembly line. By incorporating enzymes, reactions that are conventionally carried out at high temperatures and pressures can be achieved at ambient conditions. Finally, in the 21(st) century, the missions for outer space will create opportunities for MICRO-CATS to be major parts of the successful exploration of space. The future for MICRO-CATS is as wide open as outer space itself! C1 Pacific NW Natl Labs, Richland, WA 99352 USA. RP Wegeng, RS (reprint author), Pacific NW Natl Labs, POB 999, Richland, WA 99352 USA. NR 12 TC 5 Z9 5 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-66964-7 PY 2000 BP 2 EP 13 PG 12 WC Engineering, Chemical SC Engineering GA BQ57L UT WOS:000088805000001 ER PT B AU Matson, DW Martin, PM Stewart, DC Tonkovich, ALY White, M Zilka, JL Roberts, GL AF Matson, DW Martin, PM Stewart, DC Tonkovich, ALY White, M Zilka, JL Roberts, GL BE Ehrfeld, W TI Fabrication of microchannel chemical reactors using a metal lamination process SO MICROREACTION TECHNOLOGY: INDUSTRIAL PROSPECTS LA English DT Proceedings Paper CT 3rd International Conference on Microreaction Technology CY APR 18-21, 1999 CL NEW ORLEANS, LA SP Battle Memor Inst, Amer Inst Chem Engineers, Soc Chem Engn & Biotechnol, Inst Microtechnol Mainz DE microchannel; chemical reactor; lamination; combustor AB Incorporation of microchannel arrays into small-scale chemical processing devices offers significant advantages in improving thermal control in the reaction region. Development of methods to produce high aspect ratio microchannels within solid metallic structures is an important step in the evolution of manportable and other small-scale chemical processing units requiring high temperature and/or high pressure capabilities. Microchannel arrays can be used to facilitate heat removal or addition at the reaction zone or can be used to pre-heat gases prior to reaction. Staff at the Pacific Northwest National Laboratory (PNNL) have developed a method for producing solid metal components incorporating complex microchannel arrays by using a lamination and diffusion bonding process. This method uses metal shims that have been machined such that, when properly stacked, alternating microchannels and fins are produced in the laminated structure. The widths of the microchannels are determined by the thickness of the shim material, and heights and lengths of the channels are determined by the machined areas on the shims forming the channels. Machining of the shims can be accomplished in large quantities at low cost per shim by using photochemical machining or stamping processes. Consolidation of the laminated stack into a solid, leak-tight metal device is accomplished at elevated temperature and pressure by diffusion bonding. Microchannel arrays formed using this process can be produced either on the interior of the finished device or on an exterior surface. Typical microchannel dimensions in chemical processing devices produced at PNNL are 250 microns wide by 5000 microns deep. Application of the lamination process combined with a sheet-flow architecture can be used to produce highly compact chemical processing units. Among the devices produced at PNNL using this method are catalytic fuel processors and fuel vaporizers. Examples of all-metal stainless steel microchannel chemical processing devices produced using the lamination/diffusion bonding process will be presented and discussed. C1 Pacific NW Natl Labs, Richland, WA 99352 USA. RP Matson, DW (reprint author), Pacific NW Natl Labs, POB 999, Richland, WA 99352 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-66964-7 PY 2000 BP 62 EP 71 PG 10 WC Engineering, Chemical SC Engineering GA BQ57L UT WOS:000088805000006 ER PT B AU Rector, DR Palmer, BJ AF Rector, DR Palmer, BJ BE Ehrfeld, W TI Simulation of microscale chemical separation processes using the lattice-Boltzmann method SO MICROREACTION TECHNOLOGY: INDUSTRIAL PROSPECTS LA English DT Proceedings Paper CT 3rd International Conference on Microreaction Technology CY APR 18-21, 1999 CL NEW ORLEANS, LA SP Battle Memor Inst, Amer Inst Chem Engineers, Soc Chem Engn & Biotechnol, Inst Microtechnol Mainz ID GAS C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Rector, DR (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, Box 999, Richland, WA 99352 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-66964-7 PY 2000 BP 327 EP 335 PG 9 WC Engineering, Chemical SC Engineering GA BQ57L UT WOS:000088805000034 ER PT B AU Tonkovich, ALY Fitzgerald, SP Zilka, JL LaMont, MJ Wang, Y VanderWiel, DP Wegeng, RS AF Tonkovich, ALY Fitzgerald, SP Zilka, JL LaMont, MJ Wang, Y VanderWiel, DP Wegeng, RS BE Ehrfeld, W TI Microchannel chemical reactors for fuel processing applications. II. Compact fuel vaporization SO MICROREACTION TECHNOLOGY: INDUSTRIAL PROSPECTS LA English DT Proceedings Paper CT 3rd International Conference on Microreaction Technology CY APR 18-21, 1999 CL NEW ORLEANS, LA SP Battle Memor Inst, Amer Inst Chem Engineers, Soc Chem Engn & Biotechnol, Inst Microtechnol Mainz AB A fuel processor is a critical element for the deployment of automotive fuel cell power systems. One component of the fuel processor, the compact gasoline vaporizer, was demonstrated at full-scale using commercial-grade gasoline. The full-scale process volume was less than 0.3 liters; it vaporized nearly 300 mL/min of gasoline, which is sufficient to support a 50-kW(e) fuel cell. The reduction in hardware volume was made possible using a microchannel reactor-based design; the compact process hardware is roughly an order of magnitude smaller than conventional technology. C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Tonkovich, ALY (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, POB 999, Richland, WA 99352 USA. RI Wang, Yong/C-2344-2013 NR 9 TC 4 Z9 4 U1 1 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-66964-7 PY 2000 BP 364 EP 371 PG 8 WC Engineering, Chemical SC Engineering GA BQ57L UT WOS:000088805000038 ER PT B AU Drost, MK Friedrich, M Martin, C Martin, J Cameron, R AF Drost, MK Friedrich, M Martin, C Martin, J Cameron, R BE Ehrfeld, W TI Recent developments in microtechnology-based chemical heat pumps SO MICROREACTION TECHNOLOGY: INDUSTRIAL PROSPECTS LA English DT Proceedings Paper CT 3rd International Conference on Microreaction Technology CY APR 18-21, 1999 CL NEW ORLEANS, LA SP Battle Memor Inst, Amer Inst Chem Engineers, Soc Chem Engn & Biotechnol, Inst Microtechnol Mainz AB Pacific Northwest National Laboratory (PNNL) has an ongoing program focused on the development of compact chemical heat pumps based on the absorption cycle. Design and laboratory data suggest that, by taking advantage of the high rates of heat and mass transfer available in microstructures, we are able to radically reduce the size of a heat-actuated heat pump based on the absorption cycle. Current estimates suggest a size reduction of a factor of 60 compared with a conventional heat pump. High performance is achieved by using microchannel combustor technology, microchannel heat exchangers and ultra-thin-film micromachined contactors. Currently all of the components of the system have been demonstrated and PNNL is assembling a complete bench-scale version of the device. Successful development of this technology will enable a new class of compact, heat-actuated space conditioning systems that can be used for portable or distributed heating and cooling. C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Drost, MK (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, POB 999, Richland, WA 99352 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-66964-7 PY 2000 BP 394 EP 401 PG 8 WC Engineering, Chemical SC Engineering GA BQ57L UT WOS:000088805000041 ER PT B AU Lin, YH Matson, DW Kurath, DE Wen, J Xiang, F Bennett, WD Martin, PM Smith, RD AF Lin, YH Matson, DW Kurath, DE Wen, J Xiang, F Bennett, WD Martin, PM Smith, RD BE Ehrfeld, W TI Microfluidic devices on polymer substrates for bioanalytical applications SO MICROREACTION TECHNOLOGY: INDUSTRIAL PROSPECTS LA English DT Proceedings Paper CT 3rd International Conference on Microreaction Technology CY APR 18-21, 1999 CL NEW ORLEANS, LA SP Battle Memor Inst, Amer Inst Chem Engineers, Soc Chem Engn & Biotechnol, Inst Microtechnol Mainz ID MASS-SPECTROMETRY; ELECTROSPRAY C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Lin, YH (reprint author), Battelle Mem Inst, Pacific NW Natl 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 10 TC 5 Z9 5 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-66964-7 PY 2000 BP 451 EP 460 PG 10 WC Engineering, Chemical SC Engineering GA BQ57L UT WOS:000088805000047 ER PT B AU TeGrotenhuis, WE Cameron, RJ Viswanathan, VV Wegeng, RS AF TeGrotenhuis, WE Cameron, RJ Viswanathan, VV Wegeng, RS BE Ehrfeld, W TI Solvent extraction and gas absorption using microchannel contactors SO MICROREACTION TECHNOLOGY: INDUSTRIAL PROSPECTS LA English DT Proceedings Paper CT 3rd International Conference on Microreaction Technology CY APR 18-21, 1999 CL NEW ORLEANS, LA SP Battle Memor Inst, Amer Inst Chem Engineers, Soc Chem Engn & Biotechnol, Inst Microtechnol Mainz AB Microchannel devices offer many technical advantages over conventional technologies for chemical separations. The overall objective for microchemical separations is to achieve extremely high throughput per unit hardware volume by engineering devices with high contact area to volume ratios, micro-thin films, and uniform flow distribution. Pacific Northwest National Laboratory's proprietary sheet architecture is being used to construct microchannel devices consisting of channels that are 50 to 500 mu m deep and separated by porous contactor plates. Rapid mass transfer occurs between immiscible fluids, both gases and liquids, as they flow through the channels. By immobilizing the interface, both co;current and counter-current flow are achieved. The resulting improvements in heat and mass transfer rates through the devices result in dramatic improvements in productivity and efficiency. Devices have been fabricated and tested for both solvent extraction and gas absorption. Data are presented for cyclohexanol extraction from water, carbon dioxide absorption into diethanolamine, and carbon monoxide and carbon dioxide absorption into copper ammonia formate solutions. Mass transfer models based on first principles have been developed for co-current and counter-current flow for solvent extraction and gas absorption. Such predictive models are useful for evaluating the relative importance of resistances to mass transfer, predicting full-scale performance, and comparing microchannel separators with conventional technologies. Experimental data are compared with theoretical prediction. Applications for microchannel separations technology include radiochemical processing; cleanup of fuel-cell feed gases; in situ resource utilization for space exploration; recovery and sequestration of carbon dioxide for carbon management; and other separations of interest to the chemical, environmental, and pharmaceutical industries. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP TeGrotenhuis, WE (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 17 TC 19 Z9 19 U1 1 U2 4 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-66964-7 PY 2000 BP 541 EP 549 PG 9 WC Engineering, Chemical SC Engineering GA BQ57L UT WOS:000088805000056 ER PT B AU Lin, YH Matson, DW Bennett, WD Thrall, KD Timchalk, C AF Lin, YH Matson, DW Bennett, WD Thrall, KD Timchalk, C BE Ehrfeld, W TI Integrated microfluidics/electrochemical sensor system for field-monitoring of toxic metals SO MICROREACTION TECHNOLOGY: INDUSTRIAL PROSPECTS LA English DT Proceedings Paper CT 3rd International Conference on Microreaction Technology CY APR 18-21, 1999 CL NEW ORLEANS, LA SP Battle Memor Inst, Amer Inst Chem Engineers, Soc Chem Engn & Biotechnol, Inst Microtechnol Mainz ID ELECTROSPRAY C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Lin, YH (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, POB 999, Richland, WA 99352 USA. RI Lin, Yuehe/D-9762-2011 OI Lin, Yuehe/0000-0003-3791-7587 NR 8 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-66964-7 PY 2000 BP 588 EP 596 PG 9 WC Engineering, Chemical SC Engineering GA BQ57L UT WOS:000088805000062 ER PT J AU Ecker, KH Weise, HP Merkle, KL AF Ecker, KH Weise, HP Merkle, KL TI Trace analysis by heavy ion induced X-ray emission SO MIKROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 10th Conference on Solid State Analysis CY JUL 05-07, 1999 CL VIENNA UNIV TECHNOL, VIENNA, AUSTRIA SP Austrian Minist Educ Sci & Culture, Vienna Univ Technol, Inst Analyt Chem, Chemnitz Univ Technol, Inst Chem, Austrian Soc Analyt Chem, Deutsch Gesell Materialkunde, German Chem Soc, Gesell Bergbau, Deutsch Arbeitskreis Angewandte Spektroskopie, German Phys Soc, Fachverban Mikrosonden HO VIENNA UNIV TECHNOL DE PIXE; heavy ion X-ray production cross sections; trace analysis,P ACS; 32.80Hd ID PIXE SOFTWARE PACKAGE; ATOM COLLISIONS AB Various K-, L- and M-shell X-ray production cross sections are measured for heavy ion impact on elements in the range Z(2) = 13 to 83. The ion species range from Z(1) = 10 to 36, and ion energies from 1 to 16 MeV are used. Enhanced cross sections are observed when the projectile K- or L- binding energy is similar to the energy of the target K-, L- or M-shell. This effect is used to improve the analysis sensitivity for selected elements. As an example trace analysis of Fe in glass with V, Mn, Co and Ni ions is investigated. Results are compared with proton induced X-ray emission analysis on the same samples. In these samples Fe-K-alpha X-ray production is similar for ii-radiation with 3 MeV protons and 14MeV Ni ions, However the signal to background ratio is four times higher for the irradiation with Ni ions as compared to irradiation with protons. Advantages and dl drawbacks of heavy ion induced X-ray emission for quantitative analysis compared to proton induced X-ray emission analysis an discussed. C1 Fed Inst Mat Res & Testing BAM, D-12205 Berlin, Germany. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Ecker, KH (reprint author), Fed Inst Mat Res & Testing BAM, D-12205 Berlin, Germany. NR 20 TC 6 Z9 6 U1 0 U2 1 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 VIENNA, AUSTRIA SN 0026-3672 J9 MIKROCHIM ACTA JI Mikrochim. Acta PY 2000 VL 133 IS 1-4 BP 313 EP 317 DI 10.1007/s006040070112 PG 5 WC Chemistry, Analytical SC Chemistry GA 327MJ UT WOS:000087797400050 ER PT S AU Feng, WC AF Feng, WC GP IEEE IEEE TI Network traffic characterization of TCP SO MILCOM 2000: 21ST CENTURY MILITARY COMMUNICATIONS CONFERENCE PROCEEDINGS, VOLS 1 AND 2: ARCHITECTURES & TECHNOLOGIES FOR INFORMATION SUPERIORITY SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE 21st Century Military Communications Conference (MILCOM 2000) CY OCT 22-25, 2000 CL LOS ANGELES, CA SP IEEE, COMSOC, AFCEA DE TCP; distributed computing; network traffic characterization; self-similar traffic AB Networks from wireless to high-speed integrated services require support for the fluctuating and heterogeneous demands of end users. The ability to characterize the behavior of the resulting aggregate network traffic can provide insight into how traffic should be scheduled to make efficient use of the network, and yet still deliver expected quality-of-service to end users. These issues are of fundamental importance to the design of the Next-Generation Internet - from wireless communication to high-performance distributed computational grids such as NASA's Information Power Grid. Many research efforts in network traffic characterization conclude that network traffic is self-similar (i.e., fractal or bursty), and thus not amenable to the statistical-multiplexing techniques currently found in the Internet. In particular, they claim that the heavy-tailed distributions of file size, packet interarrival, and transfer duration solely contribute to the self-similarity of aggregate network traffic. In contrast, we demonstrate that it is the TCP stack itself that induces much of the self-similar behavior even when aggregated application traffic should smooth out as more applications' traffic are multiplexed. Furthermore, if random early detection (RED) gateways/routers are used, we show that network performance degrades even further due to the extra burstiness induced by the gateway itself. C1 Univ Calif Los Alamos Natl Lab, RADIANT, Los Alamos, NM 87545 USA. RP Feng, WC (reprint author), Univ Calif Los Alamos Natl Lab, RADIANT, POB 1663, Los Alamos, NM 87545 USA. EM feng@lan1.gov NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-6521-6 J9 IEEE MILIT COMMUN C PY 2000 BP 480 EP 484 PG 5 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BR85L UT WOS:000167781800092 ER PT J AU Hoddeson, L Kolb, AW AF Hoddeson, L Kolb, AW TI The Superconducting Super Collider's frontier outpost, 1983-1988 SO MINERVA LA English DT Review ID FERMILAB AB In 1993, after an optimistic beginning followed by a half-decade of conflict, the Superconducting Super Collider (SSC) project was abandoned. In an era of 'Big Science', a major scientific enterprise collapsed. Why ? We employ the metaphor of the 'frontier outpost' to analyse a critical moment in the history of this vastly expensive project, when the physicists who designed the machine were forced to recognize that traditional post-war scientific values were no longer in harmony with government priorities. C1 Univ Illinois, Dept Hist, Urbana, IL 61801 USA. Fermilab Natl Accelerator Lab, Hist & Arch Project, Batavia, IL 60510 USA. RP Univ Illinois, Dept Hist, 309 Gregory Hall, Urbana, IL 61801 USA. EM hoddeson@uiuc.edu; adrienne@fnal.gov NR 141 TC 11 Z9 11 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0026-4695 EI 1573-1871 J9 MINERVA JI Minerva PY 2000 VL 38 IS 3 BP 271 EP 310 DI 10.1023/A:1026569616118 PG 40 WC Education & Educational Research; History & Philosophy Of Science; Social Sciences, Interdisciplinary SC Education & Educational Research; History & Philosophy of Science; Social Sciences - Other Topics GA 381ZQ UT WOS:000165794300002 ER PT J AU Morris, JR Ho, KM Chen, KY Rengarajan, G Yoo, MH AF Morris, JR Ho, KM Chen, KY Rengarajan, G Yoo, MH TI Large-scale atomistic study of core structures and energetics of < c+a > {11(2)over-bar-2} dislocations in hexagonal close packed metals SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID HCP METALS; UNSTRESSED CRYSTALS; COMPUTER-SIMULATION; EDGE DISLOCATION; BEHAVIOR; SLIP; ZR AB Using two different kinds of many-body potentials as well as the Lennard-Jones potential for hexagonal close packed metals, we have found that (c + a) edge dislocations with dislocation lines along [1 (1) over bar 00] can split onto the basal plane, forming a non-planar sessile structure. The 'type I' undissociated dislocation core, observed in previous papers, is shown to be stable only for small simulations. The observed dissociated core structure has a large distorted region that we interpret as a (11 (2) over bar 1) twin nucleus, which may help the formation of (11 (2) over bar 1) tension twins. We also find that this core structure is lower in energy than the previously observed glissile 'type II' configuration, dissociated on the (11 (2) over bar 2) plane. The sessile splitting of the core gives rise to non-Schmid behaviour, with the twin nucleus expanding under c-axis tension, and contracting under compression. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Morris, JR (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. RI Morris, J/I-4452-2012 OI Morris, J/0000-0002-8464-9047 NR 27 TC 28 Z9 28 U1 0 U2 11 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD JAN PY 2000 VL 8 IS 1 BP 25 EP 35 DI 10.1088/0965-0393/8/1/303 PG 11 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 283BQ UT WOS:000085256600003 ER PT J AU El-Azab, A AF El-Azab, A TI The boundary value problem of dislocation dynamics SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID BCC SINGLE-CRYSTALS AB The present work is concerned with the mathematical formulation of the boundary value problem of dislocation dynamics. The boundary conditions for the elastic and dislocation fields are derived for two cases which are currently treated by dislocation dynamics simulation models. In the first case, the crystal space under consideration is a representative subvolume of a much larger crystal undergoing statistically homogeneous plastic distortion. The second is the case of a crystal which is bounded by a free surface. For the former case, the condition of statistical homogeneity of the elastic stress and the plastic distortion fields is used to derive local traction and dislocation flux boundary conditions on the surface of the deforming crystal space. When the crystal is bounded, the formation of slip traces is connected with the dislocation flux and dislocation emission at the free surface. Three theorems are derived, two on conservation of the total Burgers vector and the dislocation flux in a deforming crystal, and the third on image interactions. Some important mathematical ideas related to the geometry of deforming crystals are also discussed. C1 Pacific NW Lab, Richland, WA 99352 USA. RP El-Azab, A (reprint author), Pacific NW Lab, MSIN K1-96,902 Battelle Blvd,POB 999, Richland, WA 99352 USA. EM anter.el-azab@pnl.gov NR 17 TC 18 Z9 18 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD JAN PY 2000 VL 8 IS 1 BP 37 EP 54 DI 10.1088/0965-0393/8/1/304 PG 18 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 283BQ UT WOS:000085256600004 ER PT B AU McCallum, RW Dennis, KW Jiles, DC Snyder, JE Chen, YH AF McCallum, RW Dennis, KW Jiles, DC Snyder, JE Chen, YH BE Gibbs, MRJ TI Composite magnetostrictive materials for advanced automotive magnetomechanical sensors SO MODERN TRENDS IN MAGNETOSTRICTION STUDY AND APPLICATION SE NATO SCIENCE SERIES, SERIES II: MATHEMATICS, PHYSICS AND CHEMISTRY LA English DT Proceedings Paper CT Conference of the NATO Advanced-Study-Institute on Modern Trends in Magnetostriction Study and Application CY MAY 22-JUN 02, 2000 CL KIEV, UKRAINE SP NATO ID MAGNETIZATION; PARTICLES; MATRIX; STRESS; RING C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP McCallum, RW (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6716-2 J9 NATO SCI SER II MATH PY 2000 VL 5 BP 283 EP 305 PG 23 WC Physics, Condensed Matter SC Physics GA BR74N UT WOS:000167395900014 ER PT S AU Garcia, EJ AF Garcia, EJ BE Motamedi, ME Goring, R TI Pivoting micromirror designs for large orientation angles SO MOEMS AND MINIATURIZED SYSTEMS SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on MOEMS and Miniaturized Systems CY SEP 18-20, 2000 CL SANTA CLARA, CA SP SPIE, Semiconductor Equipment & Mat Int, Solid State Technol, Sandia Natl Labs DE optics; micro optics; micromirrors; MEMS; MOEMS; micro optical switches AB This paper describes mechanical design concepts for a class of pivoting micromirrors that permit relatively large angles of orientation to be obtained when configured in large arrays. Micromirror arrays can be utilized in a variety of applications ranging from optical switching to beam-front correction in a variety of technologies [1, 2]. This particular work is concerned with silicon surface micromachining (SMM). The multi-layer polysilicon surface micromachining process developed at Sandia National Laboratories is used to fabricate micromirror arrays that consist of capacitive electrode pairs which are used to electrostatically actuate mirrors to their desired positions and suitable elastic suspensions which support the 2 mum thick mirror structures. The designs described have been fabricated and successfully operated. Figure 1 illustrates a 100-mum x 100-mum micromirror actuated to 10 degrees. C1 Sandia Natl Labs, Electromech Engn Dept, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, Electromech Engn Dept, POB 5800, Albuquerque, NM 87185 USA. NR 8 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 0-8194-3834-0 J9 PROC SPIE PY 2000 VL 4178 BP 126 EP 136 DI 10.1117/12.396480 PG 11 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BR35P UT WOS:000166175100014 ER PT S AU Holswade, SC Dickey, FM AF Holswade, SC Dickey, FM BE Motamedi, ME Goring, R TI Optical sensing of microsystem motion and performance SO MOEMS AND MINIATURIZED SYSTEMS SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on MOEMS and Miniaturized Systems CY SEP 18-20, 2000 CL SANTA CLARA, CA SP SPIE, Semiconductor Equipment & Mat Int, Solid State Technol, Sandia Natl Labs DE microsensors; microactuators; optical probe; feedback; performance analysis ID SURFACE MICROMACHINED MICROENGINE; ON-CHIP DETECTION; MEMS; FRICTION; SYSTEM; ACCELEROMETER AB Microsystems involve several fabrication technologies, but share the common trait of dimensions and motions measured in microns. Small feature sizes and deflections make the detection of microdevice motion particularly difficult. The rapid operating frequencies of many microactuators compound the detection problem. Effective feedback, control, and performance measurement of microactuators thus become problematic. These measurements are particularly important, however, due to the developmental nature of many microsystem technologies. Wear, lifetime issues, and optimized drive signals, for example, are poorly understood for many actuation devices. As microactuators move out of the development stage and begin to perform work on external assemblies and environments, the various load conditions will also come into account. Since microactuators involve small masses and inertias, effective driving of external loads may require feedback-based control of the microdevice. Optical sensing technologies offer solutions to these problems of sensor motion, microactuator analysis during the development process, and integrated feedback for microactuators driving external loads. Optical methods also lend themselves to the effectively one-dimensional nature of many microsystem motions, limiting the required signal analysis to practical levels that support real-time measurement and control. This paper describes several optical techniques for sensing motion, performance, and feedback data, some of which can integrated with the microsystems themselves. For microactuators, experimental results indicate that real-time performance measurements are particularly revealing for understanding device motion and response. For microsensors, experimental results are also presented for interpreting motion using external and integrated optical techniques. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM scholsw@sandia.gov NR 36 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 0-8194-3834-0 J9 PROC SPIE PY 2000 VL 4178 BP 208 EP 220 DI 10.1117/12.396493 PG 13 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BR35P UT WOS:000166175100023 ER PT J AU Dimri, GP Itahana, K Acosta, M Campisi, J AF Dimri, GP Itahana, K Acosta, M Campisi, J TI Regulation of a senescence checkpoint response by the E2F1 transcription factor and p14(ARF) tumor suppressor SO MOLECULAR AND CELLULAR BIOLOGY LA English DT Article ID S-PHASE ENTRY; NORMAL HUMAN FIBROBLASTS; HUMAN PAPILLOMAVIRUS TYPE-16; REPLICATIVE SENESCENCE; P53-DEPENDENT APOPTOSIS; PREMATURE SENESCENCE; RETROVIRAL VECTORS; GENE-TRANSFER; G(1) ARREST; HUMAN-CELLS AB Normal cells do not divide indefinitely due to a process known as replicative senescence. Human cells arrest growth with a senescent phenotype when they acquire one or more critically short telomeres as a consequence of cell division. Recent evidence suggests that certain: types:of DNA damage, chromatin remodeling, and oncogenic forms of Ras or Raf can also elicit a senescence response. We show here that E2F1, a multifunctional transcription factor that binds the retinoblastoma (pRb) tumor suppressor and that can either promote or suppress tumorigenesis, induces a senescent phenotype when overexpressed in normal human fibroblasts. Normal human cells stably arrested proliferation and expressed several markers of replicative senescence in response to E2F1. This activity of E2F1 was independent of its pRb binding activity but dependent on its ability to stimulate gene expression. The E2F1 target gene critical for the senescence response appeared to be the p14(ARF) tumor suppressor. Replicatively senescent human fibroblasts overexpressed p14(ARF), and ectopic expression of p14(ARF) in presenescent cells induced a phenotype similar to that induced by E2F1. Consistent with a critical role for p14(ARF), cells with compromised p53 function were immune to senescence induction by E2F1, as were cells deficient in p14(ARF). Our findings support the idea that the senescence response is a critical tumor-suppressive mechanism, provide an explanation for the apparently paradoxical roles of E2F1 in oncogenesis, and identify p14(ARF) as a potentially important mediator of the senescent phenotype. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Cell & Mol Biol, Berkeley, CA 94720 USA. RP Campisi, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Cell & Mol Biol, 1 Cyclotron Rd,MS 70A-1118, Berkeley, CA 94720 USA. RI Itahana, Koji/J-5505-2013 OI Itahana, Koji/0000-0002-7241-2894 FU NIA NIH HHS [AG09909, R37 AG009909] NR 77 TC 273 Z9 281 U1 0 U2 4 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0270-7306 J9 MOL CELL BIOL JI Mol. Cell. Biol. PD JAN PY 2000 VL 20 IS 1 BP 273 EP 285 PG 13 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 265DY UT WOS:000084227100028 PM 10594030 ER PT J AU Bruno, WJ Socci, ND Halpern, AL AF Bruno, WJ Socci, ND Halpern, AL TI Weighted neighbor joining: A likelihood-based approach to distance-based phylogeny reconstruction SO MOLECULAR BIOLOGY AND EVOLUTION LA English DT Article DE Weighbor; evolutionary tree reconstruction; distance methods; long-branch attraction; long branch distracts ID EVOLUTIONARY DISTANCES; MAXIMUM-LIKELIHOOD; MOLECULAR DISTANCE; LEAST-SQUARES; DNA-SEQUENCES; TREES; SUBSTITUTIONS; HUMANS AB We introduce a distance-based phylogeny reconstruction method called "weighted neighbor joining," or "Weighbor" for short. As in neighbor joining, two taxa are joined in each iteration; however, the Weighbor criterion for choosing a pair of taxa to join takes into account that errors in distance estimates are exponentially larger for longer distances. The criterion embodies a likelihood function on the distances, which are modeled as correlated Gaussian random variables with different means and variances, computed under a probabilistic model for sequence evolution. The Weighbor criterion consists of two terms, an additivity term and a positivity term, that quantify the implications of joining the pair. The first term evaluates deviations from additivity of the implied external branches, while the second term evaluates confidence that the implied internal branch has a positive branch length. Compared with maximum-likelihood phylogeny reconstruction, Weighbor is much faster, while building trees that are qualitatively and quantitatively similar. Weighbor appears to be relatively immune to the "long branches attract" and "long branch distracts" drawbacks observed with neighbor joining, BIONJ, and parsimony. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Lucent Technol, Bell Labs, Dept Theoret Phys, Murray Hill, NJ USA. Rockefeller Univ, New York, NY 10021 USA. Univ New Mexico, Dept Mol Genet & Microbiol, Hlth Sci Ctr, Albuquerque, NM 87131 USA. RP Bruno, WJ (reprint author), Univ Calif Los Alamos Natl Lab, MS K-710, Los Alamos, NM 87545 USA. FU NCRR NIH HHS [5P20-RR11830-02] NR 22 TC 284 Z9 290 U1 1 U2 7 PU SOC MOLECULAR BIOLOGY EVOLUTION PI LAWRENCE PA PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0737-4038 J9 MOL BIOL EVOL JI Mol. Biol. Evol. PD JAN PY 2000 VL 17 IS 1 BP 189 EP 197 PG 9 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 277DJ UT WOS:000084917200018 PM 10666718 ER PT J AU Pitkin, JW Nikolskaya, A Ahn, JH Walton, JD AF Pitkin, JW Nikolskaya, A Ahn, JH Walton, JD TI Reduced virulence caused by meiotic instability of the TOX2 chromosome of the maize pathogen Cochliobolus carbonum SO MOLECULAR PLANT-MICROBE INTERACTIONS LA English DT Article ID FILAMENTOUS FUNGI; COLLETOTRICHUM-GLOEOSPORIOIDES; LENGTH-POLYMORPHISM; HC-TOXIN; GENE; KARYOTYPE; LOCUS AB The mechanisms by which pathogenic fungi evolve are poorly understood. Production of the host-selective cyclic peptide HC-toxin is controlled by a complex locus, TOX2, in the plant pathogen Cochliobolus carbonum, Crosses between toxin-producing (Tox2(+)) and toxin-nonproducing (Tox2(-)) isolates, as well as crosses between isolates in which the TOX2 genes were on chromosomes of different size, yielded progeny that had lost one or more copies of one or more of the TOX2 genes. Of approximately 200 progeny analyzed, eight (4%) had lost at least one TOX2 gene. All of them still had at least one functional copy of all of the known genes required for IHC-toxin production (HTS1, TOXA, TOXC, and TOXE), Most deletion strains could be explained by simple chromosome breaks resulting in the loss of major contiguous portions (0.8 to 1.4 Mb) of the 3.5-Mb TOX2 chromosome, whereas others had more complicated patterns. All deletion strains had normal growth and were fertile, indicating that the 1.4 Mb of DNA contained no essential housekeeping genes. Most strains were also still virulent (Tox2(+)), but two had a novel phenotype of reduced virulence (RV), characterized by smaller lesions that expanded at a reduced rate and an inability to colonize plants systemically, Although the RV strains made no detectable HC-toxin in culture, the RV phenotype was dependent on the presence of a functional copy of HTS1, which encodes the central enzyme in HC-toxin biosynthesis. We propose that the RV strains still make a low level of HC-toxin, at least in planta, and that this is due to the loss of one or more genes that contribute to, but are not absolutely required for, HC-toxin synthesis. C1 Michigan State Univ, US DOE, Plant Res Lab, E Lansing, MI 48824 USA. Michigan State Univ, Genet Program, E Lansing, MI 48824 USA. Michigan State Univ, Dept Bot & Plant Pathol, E Lansing, MI 48824 USA. RP Walton, JD (reprint author), Michigan State Univ, US DOE, Plant Res Lab, E Lansing, MI 48824 USA. NR 25 TC 15 Z9 18 U1 0 U2 2 PU AMER PHYTOPATHOLOGICAL SOC PI ST PAUL PA 3340 PILOT KNOB ROAD, ST PAUL, MN 55121 USA SN 0894-0282 J9 MOL PLANT MICROBE IN JI Mol. Plant-Microbe Interact. PD JAN PY 2000 VL 13 IS 1 BP 80 EP 87 DI 10.1094/MPMI.2000.13.1.80 PG 8 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Plant Sciences SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Plant Sciences GA 267XV UT WOS:000084385300009 PM 10656588 ER PT J AU He, XY Li, N Goldstein, B AF He, XY Li, N Goldstein, B TI Lattice Boltzmann simulation of diffusion-convection systems with surface chemical reaction SO MOLECULAR SIMULATION LA English DT Article; Proceedings Paper CT Virtual Conference on Applications and Methodology of Molecular Simulation in the Physical and Biological Sciences CY APR 19-MAY 04, 1999 CL ELECTR NETWORK SP Molec Simulat DE lattice Boltzmann simulation; diffusion-convection; surface chemical reaction ID POROUS-MEDIA; MODEL; FLOW; FLUIDS AB Chemical reactions on solid surfaces are ubiquitous in natural and industrial processes. In many situations, the reaction is complicated by diffusion and convection of reactants in the surrounding media. The system as a whole is usually highly nonlinear. Theoretical analysis for this complicated phenomenon is difficult if not entirely impossible. It is highly desired to develop efficient computational tools to simulate this process. The lattice Boltzmann method, based on mesoscopic description of fluid systems, is quits suitable for this purpose. This study will present a lattice Boltzmann scheme for simulating the diffusion-convection systems with surface chemical reactions. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP He, XY (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 22 TC 40 Z9 42 U1 3 U2 16 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0892-7022 J9 MOL SIMULAT JI Mol. Simul. PY 2000 VL 25 IS 3-4 BP 145 EP 156 DI 10.1080/08927020008044120 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 355VQ UT WOS:000089409600003 ER PT J AU Shenderova, OA Brenner, DW Omeltchenko, A Su, X Yang, LH Nazarov, A AF Shenderova, OA Brenner, DW Omeltchenko, A Su, X Yang, LH Nazarov, A TI Properties of polycrystalline diamond: Multiscale modeling approach SO MOLECULAR SIMULATION LA English DT Article; Proceedings Paper CT Virtual Conference on Applications and Methodology of Molecular Simulation in the Physical and Biological Sciences CY APR 19-MAY 04, 1999 CL ELECTR NETWORK SP Molec Simulat DE diamond; grain boundaries; fracture properties; electronic properties; simulation; polycrystalline diamond; multiscale modeling approach ID GRAIN-BOUNDARIES; FIELD-EMISSION; FRACTURE; ENERGY AB Two modeling techniques to characterize fracture behavior of polycrystalline diamond films are discussed. The first technique is a multiscale modeling method in which first-principles local density approximation calculations on selected structures are combined with an analytic mesoscale model to obtain energies and cleavage fracture energies for symmetric [001] tilt grain boundaries (GBs) over the entire misorientation range. The second technique is large-scale atomistic simulation of the dynamics of failure in notched polycrystalline diamond samples under an applied strain. Electronic characteristics of selected [001] symmetrical tilt GBs calculated with a semiempirical tight-binding Hamiltonian are also presented, and the possible role of graphitic defects on field emission from polycrystalline diamond is briefly discussed. C1 N Carolina State Univ, Raleigh, NC 27695 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Russian Acad Sci, Inst Met Superplast Problems, Ufa 450001, Russia. RP Shenderova, OA (reprint author), N Carolina State Univ, Raleigh, NC 27695 USA. RI Brenner, Donald/D-1741-2009 NR 21 TC 2 Z9 2 U1 0 U2 10 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0892-7022 J9 MOL SIMULAT JI Mol. Simul. PY 2000 VL 24 IS 1-3 BP 197 EP 207 DI 10.1080/08927020008024196 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 355VK UT WOS:000089409100014 ER PT B AU Costa, DA Smith, WH Dewey, HJ AF Costa, DA Smith, WH Dewey, HJ BE Trulove, PC DeLong, HC Stafford, GR Deki, S TI Actinide chemistry in the EMIC/AlCl3 room temperature ionic liquid SO MOLTEN SALTS XII, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 12th International Symposium on Molten Salts CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Div Phys Electrochem, Electrochem Soc, Div High Temp Mat, Electrochem Soc, Div Electrodeposit, USAF, Off Sci Res, European Off Aersp Res & Dev ID MOLTEN-SALTS; CHLORIDE; ELECTROCHEMISTRY; SPECTROSCOPY; UO22+ AB We have previously reported on the redox behavior of uranyl chloride in acidic ionic liquids. The uranyl moiety is unstable to oxygen loss in this melt with the concomitant growth of a uranium (V) chloride species. We proposed that an equilibrium is established between the Lewis acidic Al2Cl7 and the uranium oxy-chloride species. Similar behavior may be expected for plutonium oxide species. We have demonstrated that a basic EMIC/AlCl3 solution of PuCl3 displays one reversible oxidation and an irreversible reduction. The reversible wave has been confirmed to be associated with the Pu (III)/Pu (IV) redox couple by comparison with the cyclic voltammogram of an authentic sample of Cs2PuCl6. The irreversible reduction wave is believed to come from the reduction of a plutonium oxide contaminant. In this talk we focus on our work on the chemistry of uranium and plutonium ore-complexes in 1-ethyl-3-methylimidazolium chloride / aluminum chloride ionic liquid. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Costa, DA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 25 TC 7 Z9 7 U1 1 U2 4 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-264-8 J9 ELEC SOC S PY 2000 VL 99 IS 41 BP 80 EP 99 PG 20 WC Chemistry, Inorganic & Nuclear; Electrochemistry SC Chemistry; Electrochemistry GA BQ13W UT WOS:000087280700010 ER PT B AU Mao, G Baboul, AG Curtiss, LA Price, DL Saboungi, ML Armand, MB Howells, WS Fischer, HE AF Mao, G Baboul, AG Curtiss, LA Price, DL Saboungi, ML Armand, MB Howells, WS Fischer, HE BE Trulove, PC DeLong, HC Stafford, GR Deki, S TI Structure and dynamics of lithium polymer electrolytes SO MOLTEN SALTS XII, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 12th International Symposium on Molten Salts CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Div Phys Electrochem, Electrochem Soc, Div High Temp Mat, Electrochem Soc, Div Electrodeposit, USAF, Off Sci Res, European Off Aersp Res & Dev ID POLY(ETHYLENE; CONDUCTIVITY; COMPLEXES; MIGRATION; BARRIERS AB The atomic structure and dynamics of PEO-LiClO4 and PEO-LiTFSI polymer electrolytes have been investigated by neutron scattering experiments and ab initio quantum chemical calculations. The Li+ ions are bonded to, on average, five ether-oxygen atoms of the polymer host with an average bond length of 2.1 Angstrom. No cation-anion pairing is observed.. On a time scale of 0.01 - 0.1 ns, the segmental motion of the PEO chains is significantly altered by the introduction of the salts compared to pure PEG. The cross-links through the Li-O coordination bonds are believed to be responsible for the change in the dynamics. These results are consistent with a mechanism in which Li+ ion transport takes place through the dynamical formation and disruption of Li-O bonds. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Mao, G (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Price, David Long/A-8468-2013; Saboungi, Marie-Louise/C-5920-2013; Fischer, Henry/D-5299-2012 OI Saboungi, Marie-Louise/0000-0002-0607-4815; Fischer, Henry/0000-0002-1204-0750 NR 11 TC 0 Z9 0 U1 0 U2 5 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-264-8 J9 ELEC SOC S PY 2000 VL 99 IS 41 BP 247 EP 252 PG 6 WC Chemistry, Inorganic & Nuclear; Electrochemistry SC Chemistry; Electrochemistry GA BQ13W UT WOS:000087280700028 ER PT B AU Guidotti, RA Reinhardt, FW AF Guidotti, RA Reinhardt, FW BE Trulove, PC DeLong, HC Stafford, GR Deki, S TI Performance of Li-alloy/Ag2CrO4 couples in molten CsBr-LiBr-KBr eutectic SO MOLTEN SALTS XII, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 12th International Symposium on Molten Salts CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Div Phys Electrochem, Electrochem Soc, Div High Temp Mat, Electrochem Soc, Div Electrodeposit, USAF, Off Sci Res, European Off Aersp Res & Dev AB The performance of Li-alloy/CsBr-LiBr-KBr/Ag2CrO4 systems was studied over a temperature range of 250 degrees C to 300 degrees C, for possible use as a power source for geothermal borehole applications. Single cells were discharged at current densities of 15.8 and 32.6 mA/cm(2) using Li-Si and Li-Al anodes. When tested in 5-cell batteries, the Li-Si/CsBr-LiBr-KBr/Ag2CrO4 system exhibited thermal runaway. Thermal analytical tests showed that the Ag2CrO4 cathode reacted exothermically with the electrolyte on activation. Consequently, this system would not be practical for the envisioned geothermal borehole applications. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Guidotti, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 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 1-56677-264-8 J9 ELEC SOC S PY 2000 VL 99 IS 41 BP 451 EP 460 PG 10 WC Chemistry, Inorganic & Nuclear; Electrochemistry SC Chemistry; Electrochemistry GA BQ13W UT WOS:000087280700050 ER PT B AU Guidotti, RA Reinhardt, FW AF Guidotti, RA Reinhardt, FW BE Trulove, PC DeLong, HC Stafford, GR Deki, S TI Characterization of the LiSi/CsBr-LiBr-KBr/FeS2 system for potential use as a geothermal battery source SO MOLTEN SALTS XII, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 12th International Symposium on Molten Salts CY OCT 17-22, 1999 CL HONOLULU, HI SP Electrochem Soc, Div Phys Electrochem, Electrochem Soc, Div High Temp Mat, Electrochem Soc, Div Electrodeposit, USAF, Off Sci Res, European Off Aersp Res & Dev AB The suitability of modified thermal-battery technology as a potential power source for geothermal borehole applications is continuing to be studied. Previous work has focused on the LiSi/FeS2 couple over a temperature range of 350 degrees C to 400 degrees C with the LiBr-KBr-LiF eutectic, which melts at 324.5 degrees C. In this work, the discharge processes that take place in LiSi/CsBr-LiBr-KBr eutectic/FeS2 thermal cells were studied at temperatures between 250 degrees C and 400 degrees C using pelletized cells with immobilized electrolyte The CsBr-LiBr-KBr eutectic was selected because of its lower melting point (228.5 degrees C). Incorporation of a quasi-reference electrode allowed the determination of the relative contribution of each electrode to the overall cell polarization. The results of single-cell tests and limited battery tests are presented, along with preliminary data for battery stacks tested in a simulated geothermal borehole environment. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Guidotti, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 2 Z9 2 U1 2 U2 4 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-264-8 J9 ELEC SOC S PY 2000 VL 99 IS 41 BP 701 EP 712 PG 12 WC Chemistry, Inorganic & Nuclear; Electrochemistry SC Chemistry; Electrochemistry GA BQ13W UT WOS:000087280700075 ER PT B AU Booth, TE AF Booth, TE BE Niederreiter, H Spanier, J TI Adaptively learning an importance function using transport constrained Monte Carlo SO MONTE CARLO AND QUASI-MONTE CARLO METHODS 1998 LA English DT Proceedings Paper CT 3rd International Conference on Monte Carlo and Quasi-Monte Carlo Methods in Scientific Computing (MCQM 98) CY JUN 22-26, 1998 CL CLAREMONT GRAD UNIV, CLAREMONT, CA SP Natl Sci Fdn, Natl Secur Agcy, US DOE, USA, Res Off HO CLAREMONT GRAD UNIV AB It is well known that a Monte Carlo estimate can be obtained with zero-variance if an exact importance function for the estimate is known. There are many ways that one might iteratively seek to obtain an ever more exact importance function. This paper describes a method that has obtained ever more exact importance functions that empirically produce an error that is dropping exponentially with computer time. The method described herein constrains the importance function to satisfy the (adjoint) Boltzmann transport equation. This constraint is provided by using the known form of the solution, usually referred to as the Case eigenfunction solution. C1 Univ Calif Los Alamos Natl Lab, Code Integrat Grp XC1, Los Alamos, NM 87545 USA. RP Booth, TE (reprint author), Univ Calif Los Alamos Natl Lab, Code Integrat Grp XC1, Mail Stop F663, Los Alamos, NM 87545 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-66176-X PY 2000 BP 1 EP 15 PG 15 WC Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA BQ71U UT WOS:000089259100001 ER PT S AU Modine, NA Kim, H Kaxiras, E AF Modine, NA Kim, H Kaxiras, E BE Millunchick, JM Barabasi, AL Modine, NA Jones, ED TI Ab-initio studies of AlSb (001) adatom behavior and reconstruction SO MORPHOLOGICAL AND COMPOSITIONAL EVOLUTION OF HETEROEPITAXIAL SEMICONDUCTOR THIN FILMS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium K on Morphological and Compositional Evolution of Heteroepitaxial Semiconductor Thin Films held at the 2000 MRS Spring Meeting CY APR 24-27, 2000 CL SAN FRANCISCO, CA SP Mat Res Soc, Natl Sci Fdn, EPI MBE Products Grp, RHK Techno, SVT Associates, kSpace Associates ID TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; MOLECULAR-DYNAMICS; GAAS(001); SURFACES; METALS; MODEL AB We discuss a recent investigation of adatom behavior on the AlSb(001) surface using first-principles electronic structure methods based on the density functional theory. For Al and Sb adatoms, we find a number of novel adatom structures that differ dramatically from previous results for the superficially similar group-III arsenides. In particular, we conclude that it is energetically favorable for an Al adatom to incorporate substitutionally into the outermost layer of the AlSb surface. This observation helps motivate a proposed new reconstruction for the AlSb(001) surface. Finally, we argue that the unusual adatom behavior identified for this surface probably results from the presence of a dimer row composed of a double layer of group-V atoms in the reconstruction, and therefore, it should be generic to all of the antimonides, as well as, the c(4 x 4) reconstruction of the arsenides and phosphides. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Modine, NA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 17 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 1-55899-526-9 J9 MATER RES SOC SYMP P PY 2000 VL 618 BP 11 EP 19 PG 9 WC Materials Science, Coatings & Films; Physics, Condensed Matter SC Materials Science; Physics GA BR94F UT WOS:000168127800002 ER PT S AU Jasinski, J Babinski, A Czeczott, M Bozek, R AF Jasinski, J Babinski, A Czeczott, M Bozek, R BE Millunchick, JM Barabasi, AL Modine, NA Jones, ED TI InGaAs/GaAs quantum dot interdiffusion induced by cap layer overgrowth SO MORPHOLOGICAL AND COMPOSITIONAL EVOLUTION OF HETEROEPITAXIAL SEMICONDUCTOR THIN FILMS SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium K on Morphological and Compositional Evolution of Heteroepitaxial Semiconductor Thin Films held at the 2000 MRS Spring Meeting CY APR 24-27, 2000 CL SAN FRANCISCO, CA SP Mat Res Soc, Natl Sci Fdn, EPI MBE Products Grp, RHK Techno, SVT Associates, kSpace Associates ID STRANSKI-KRASTANOW GROWTH; INFRARED PHOTODETECTORS; RADIATIVE EMISSION; ADATOM MIGRATION; CAPPING LAYER; LUMINESCENCE; ENSEMBLES AB The effect of thermal treatment during and after growth of InGaAs/GaAs quantum dot (QD) structures was studied. Transmission electron microscopy and atomic force microscopy confirmed the presence of interacting QDs, as was expected from analysis of temperature dependence of QD photoluminescence (PL) peak. The results indicate that the effect of postgrowth annealing can be similar to the effect of elevated temperature of capping layer growth. Both, these thermal treatments can lead to a similar In and Ga interdiffusion resulting in a similar blue-shift of QD PL peak. C1 Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. OI Babinski, Adam/0000-0002-5591-4825 NR 27 TC 1 Z9 1 U1 0 U2 1 PU MATERIALS RESEARCH SOC PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-526-9 J9 MATER RES SOC SYMP P PY 2000 VL 618 BP 179 EP 184 PG 6 WC Materials Science, Coatings & Films; Physics, Condensed Matter SC Materials Science; Physics GA BR94F UT WOS:000168127800025 ER PT J AU Bartram, ME AF Bartram, ME TI Improvements in bis(cyclopentadienyl) magnesium purity as determined with gas chromatography-mass spectroscopy SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article AB Bis(cyclopentadienyl) magnesium (MgCp2) is used commonly as a source for doping nitride materials with magnesium. Increased oxygen incorporation known to accompany the use of MgCp2 makes the purity of this precursor an important consideration in nitride CVD. Gas chromatography-mass spectroscopy (GCMS) methods have now been developed for the identification of volatile impurities in MgCp2. Diethylether, an oxygen containing organic compound (CH(3)CH(2)OCH(2)CH(3)), and additional organic impurities were found in the MgCp2 supplied by three manufacturers. Subsequent refinements in the synthetic processes by these companies have resulted in the availability of MgCp2 free of ether and other organic impurities as determined by GCMS. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Bartram, ME (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 5 TC 16 Z9 17 U1 2 U2 2 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 2000 VL 5 IS 4 BP 1 EP 5 AR 4 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 368EG UT WOS:000090104300001 ER PT J AU Pearton, SJ Shul, RJ Ren, F AF Pearton, SJ Shul, RJ Ren, F TI A review of dry etching of GaN and related materials SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Review ID HETEROJUNCTION BIPOLAR-TRANSISTOR; PLASMA AB The characteristics of dry etching of the AlGaInN materials system in different reactor types and plasma chemistries are reviewed, along with the depth and thermal stability of etch-induced damage. The application to device processing for both electronics and photonics is also discussed. 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 Pearton, SJ (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 15 TC 53 Z9 56 U1 6 U2 28 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 2000 VL 5 IS 11 BP 1 EP 38 AR 11 PG 38 WC Materials Science, Multidisciplinary SC Materials Science GA 385EW UT WOS:000165990500001 ER PT J AU Benamara, M Liliental-Weber, Z Mazur, JH Swider, W Washburn, J Iwaya, M Akasaki, I Amano, H AF Benamara, M Liliental-Weber, Z Mazur, JH Swider, W Washburn, J Iwaya, M Akasaki, I Amano, H TI The role of the multi buffer layer technique on the structural quality of GaN SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc AB Successive growth of thick GaN layers separated by either LT-GaN or LT-AlN interlayers have been investigated by transmission electron microscopy techniques. One of the objectives of this growth method was to improve the quality of GaN layers by reducing the dislocation density at the intermediate buffer layers that act as barriers to dislocation propagation. While the use of LT-AlN results in the multiplication of dislocations in the subsequent GaN layers, the LT-GaN reduces dislocation density. Based upon Burgers vector analysis, the efficiency of the buffer layers for the propagation of the different type of dislocations is presented. LT-AlN layer favor the generation of edge dislocations, leading to a highly defective GaN layer. On the other hand, the use of LT-GaN as intermediate buffer layers appears as a promising method to obtain high quality GaN layer. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Meijo Univ, Dept Elect & Elect Engn, Tempaku Ku, Nagoya, Aichi 4688502, Japan. RP Benamara, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 4 TC 0 Z9 0 U1 1 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 2000 VL 5 SU 1 BP art. no. EP W5.8 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600057 ER PT J AU Cao, XA Pearton, SJ Dang, GT Zhang, AP Ren, F Shul, RJ Zhang, L Hickman, R Van Hove, JM AF Cao, XA Pearton, SJ Dang, GT Zhang, AP Ren, F Shul, RJ Zhang, L Hickman, R Van Hove, JM TI Surface conversion effects in plasma-damaged p-GaN SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID ETCHING-INDUCED DAMAGE; SCHOTTKY DIODES; GALLIUM NITRIDE; TRANSISTOR AB The near-surface (400-500 Angstrom) of p-GaN exposed to high density plasmas is found to become more compensated through the introduction of shallow donors. At high ion fluxes or ion energies there can be type-conversion of this surface region. Two different methods for removal of the damaged surface were investigated; wet etching in KOH, which produced self-limiting etch depths or thermal annealing under N-2 which largely restored the initial electrical properties. 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. SVT Associates, Eden Prairie, MN 55344 USA. RP Cao, XA (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 26 TC 2 Z9 3 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 2000 VL 5 SU 1 BP art. no. EP W10.8 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600077 ER PT J AU Chen, WL Gunshor, RL Han, J Higashimine, K Otsuka, N AF Chen, WL Gunshor, RL Han, J Higashimine, K Otsuka, N TI Growth of InN by MBE SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID VAPOR-PHASE EPITAXY; MOLECULAR-BEAM EPITAXY; THIN-FILMS; STRUCTURAL-PROPERTIES; GAN; ALN AB A series of experiments were performed to explore the growth of InN by Molecular Beam Epitaxy (MBE). The growth conditions were optimized based on the study of RHEED during growth and InN dissociation experiments. Characterization of the InN thin films were performed by various techniques such as TEM and XRD. C1 Purdue Univ, Sch Elect & Comp Engn, W Lafayette, IN 47907 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Chen, WL (reprint author), Purdue Univ, Sch Elect & Comp Engn, W Lafayette, IN 47907 USA. NR 17 TC 5 Z9 6 U1 1 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 2000 VL 5 SU 1 BP art. no. EP W3.30 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600027 ER PT J AU Dang, G Cao, XA Ren, F Pearton, SJ Han, J Baca, AG Shul, RJ Wilson, RG AF Dang, G Cao, XA Ren, F Pearton, SJ Han, J Baca, AG Shul, RJ Wilson, RG TI Comparison of implant isolation species for GaN field-effect transistor structures SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID ION-IMPLANTATION; NITROGEN; ALGAAS AB Different ions (Ti+, O+, Fe+, Cr+) were implanted at multiple energies into GaN field effect transistor structures (n and p-type). The implantation was found to create deep states with energy levels in the range E-C -0.20 to 0.49 eV in n-GaN and at E-v +0.44 eV in p-GaN after annealing at 450-650 degreesC. The sheet resistance of the GaN was at a maximum after annealing at these temperatures, reaching values of similar to 4x10(12) Omega/square in n-GaN and similar to 10(10) Omega/square in p-GaN. The mechanism for the implant isolation was damage-related trap formation for all of the ions investigated, and there was no evidence of chemically induced isolation. C1 Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Dang, G (reprint author), Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. NR 13 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 2000 VL 5 SU 1 BP art. no. EP W11.68 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600117 ER PT J AU Han, J Figiel, JJ Petersen, GA Myers, SM Crawford, MH Banas, MA Hearne, SJ AF Han, J Figiel, JJ Petersen, GA Myers, SM Crawford, MH Banas, MA Hearne, SJ TI MOVPE growth of quaternary (Al,Ga,In)N for UV optoelectronics SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID CHEMICAL-VAPOR-DEPOSITION; LIGHT-EMITTING DIODES; LOCALIZED EXCITONS; NITRIDE COMPOUNDS; QUANTUM-WELLS; GAN; INGAN; EVOLUTION; STRAIN; ALLOYS AB We report the growth and characterization of quaternary AlGalnN. A combination of photoluminescence (PL), high-resolution x-ray diffraction (XRD), and Rutherford backscattering spectrometry (RBS) characterizations enables us to explore the contours of constant- PL peak energy and lattice parameter as functions of the quaternary compositions. The observation of room temperature PL emission at 351nm (with 20% Al and 5% In) renders initial evidence that the quaternary could be used to provide confinement for GaInN land possibly GaN). AlGaInN/GaInN MQW heterostructures have been grown; both XRD and PL measurements suggest the possibility of incorporating this quaternary into optoelectronic devices. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Han, J (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 33 TC 0 Z9 0 U1 0 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 2000 VL 5 SU 1 BP art. no. EP W6.2 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600059 ER PT J AU Mazur, JH Benamara, M Liliental-Weber, Z Swider, W Washburn, J Eiting, CJ Dupuis, RD AF Mazur, JH Benamara, M Liliental-Weber, Z Swider, W Washburn, J Eiting, CJ Dupuis, RD TI Effect of the doping and the Al content on the microstructure and morphology of thin AlxGa1-xN layers grown by MOCVD. SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc AB AlxGa1-xN {x=30% (doped and undoped), 45% (doped)} thin films were grown by MOCVD on similar to2 mum thick GaN layer using Al2O3 substrate. These films were designed to be the active parts of HFETs with n(s)mu product of about 10(16)(Vs)(-1). The layers were then studied by means of transmission electron microscopy (TEM) techniques. In this paper, it is shown that the AlxGa1-xN layer thickness was non-uniform due to the presence of V-shaped defects within the AlxGa1-xN films. The nucleation of these V-shaped defects has taken place about 20 nm above the AlxGa1-xN/GaN interface. Many of these V-shaped defects were associated with the presence of the threading dislocations propagating from the GaN/Al2O3 interface. We show that the density of these V-shaped defects increases with the doping level and also with the Al mole fraction in the films. The formation mechanism of the V-shaped defects seems to be related to the concentration of dopants or other impurities at the ledges of the growing film This suggestion is supported by high resolution TEM analysis. The growth front between the V-shaped defects in the lower Al concentration thin films was planar as compared with the three-dimensional growth in the doped, higher Al concentration film. This interpretation of the origin of the V-shaped defects is consistent with the observed lowering of the Schottky barrier height in n-doped AlGaN/Ni Schottky diodes. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Texas, Microelect Res Ctr, Austin, TX 78712 USA. RP Mazur, JH (reprint author), Philips Semicond, 9651 Westoverhills Blvd, San Antonio, TX 78251 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 3 TC 2 Z9 2 U1 0 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 2000 VL 5 SU 1 BP art. no. EP W3.77 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600042 ER PT J AU Myers, SM Wright, AF Petersen, GA Seager, CH Crawford, MH Wampler, WR Han, J AF Myers, SM Wright, AF Petersen, GA Seager, CH Crawford, MH Wampler, WR Han, J TI Simulation of H behavior in p-GaN(Mg) at elevated temperatures SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID GAN FILMS; HYDROGEN AB The behavior of H in p-GaN(Mg) at temperatures >400 degreesC is modeled by using energies and vibration frequencies from density-functional theory to parameterize transport and reaction equations. Predictions agree semiquantitatively with experiment for the solubility, uptake, and release of the H when account is taken of a surface barrier. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Myers, SM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 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 2000 VL 5 SU 1 BP art. no. EP W9.4 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600069 ER PT J AU Shapiro, NA Perlin, P Kisielowski, C Mattos, LS Yang, JW Weber, ER AF Shapiro, NA Perlin, P Kisielowski, C Mattos, LS Yang, JW Weber, ER TI The effects of indium concentration and well-thickness on the mechanisms of radiative recombination in InxGa1-xN quantum wells SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID LOCALIZED EXCITONS; TEMPERATURE; EMISSION; SINGLE AB A correlation of the local indium concentration measured on an atomic scale with luminescence properties of InxGa1-xN quantum wells reveals two different types of recombination mechanisms. A piezoelectric-field based mechanism is shown to dominate in samples with thick wells (L > 3 nm) of low indium concentration (x < 0.15-0.20). Spatial indium concentration fluctuations dominate luminescence properties in samples of higher indium concentrations in thinner wells. Quantum confinement is shown to have a major effect on the radiative recombination energy. A model is presented that relates the experimentally measured nano scale structural and chemical properties of quantum wells to the characteristics of the luminescence. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, High Pressure Res Ctr, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Shapiro, NA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 20 TC 55 Z9 56 U1 1 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 2000 VL 5 IS 1 BP art. no. EP 1 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 306TQ UT WOS:000086613000001 ER PT J AU Spruytte, SG Coldren, CW Marshall, AF Larson, MC Harris, JS AF Spruytte, SG Coldren, CW Marshall, AF Larson, MC Harris, JS TI MBE growth of nitride-arsenide materials for long wavelength opto-electronics SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID MOLECULAR-BEAM EPITAXY AB Nitride-Arsenide materials were grown by molecular beam epitaxy (MBE) using a radio frequency (rf) nitrogen plasma. The plasma conditions that maximize the amount of atomic nitrogen versus molecular nitrogen were determined using the emission spectrum of the plasma. Under constant plasma source conditions and varying group III flux, the nitrogen concentration in the film is inversely proportional to the group III flux (i.e. the nitrogen sticking coefficient is unity). The relationship between nitrogen concentration in the film and lattice parameter of the film is not linear for nitrogen concentrations above 2.9 mole % GaN, indicating that some nitrogen is incorporated on other locations than the group V lattice sites. For films with these higher nitrogen concentrations, XPS indicates that the nitrogen exists in two configurations: a Gallium-Nitrogen bond and another type of nitrogen complex in which nitrogen is less strongly bonded to Gallium atoms. Annealing removes this nitrogen complex and allows some of the nitrogen to diffuse out of the film. Annealing also improves the crystal quality of GaAsN quantum wells. C1 Stanford Univ, Solid State & Photon Lab, Stanford, CA 94305 USA. Stanford Univ, Ctr Mat Res, Stanford, CA 94305 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Spruytte, SG (reprint author), Stanford Univ, Solid State & Photon Lab, Stanford, CA 94305 USA. NR 9 TC 1 Z9 1 U1 0 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 2000 VL 5 SU 1 BP art. no. EP W8.4 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600067 ER PT J AU Zhang, AP Dang, GT Cao, XA Cho, H Ren, F Han, J Chyi, JI Lee, CM Nee, TE Chuo, CC Chi, GC Chu, SNG Wilson, RG Pearton, SJ AF Zhang, AP Dang, GT Cao, XA Cho, H Ren, F Han, J Chyi, JI Lee, CM Nee, TE Chuo, CC Chi, GC Chu, SNG Wilson, RG Pearton, SJ TI Processing and device performance of GaN power rectifiers SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc AB Mesa and planar geometry GaN Schottky rectifiers were fabricated on 3-12 mum thick epitaxial layers. In planar diodes utilizing resistive GaN, a reverse breakdown voltage of 3.1 kV was achieved in structures containing p-guard rings and employing extension of the Schottky contact edge over an oxide layer. In devices without edge termination, the reverse breakdown voltage was 2.3 kV. Mesa diodes fabricated on conducting GaN had breakdown voltages in the range 200-400 V, with on-state resistances as low as 6m Omega .cm(-2). C1 Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Natl Cent Univ, Dept Elect Engn, Chungli 32054, Taiwan. Natl Cent Univ, Dept Phys, Chungli 32054, Taiwan. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. RP Zhang, AP (reprint author), Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. RI Chyi, Jen-Inn/A-1799-2016 NR 6 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 2000 VL 5 SU 1 BP art. no. EP W11.67 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600116 ER PT J AU Zhang, L Lester, LF Baca, AG Shul, RJ Chang, PC Willison, CG Mishra, UK Denbaars, SP Zolper, JC AF Zhang, L Lester, LF Baca, AG Shul, RJ Chang, PC Willison, CG Mishra, UK Denbaars, SP Zolper, JC TI Fabrication and characterization of GaN junctionfield effect transistors SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID FIELD-EFFECT TRANSISTORS; P-N-JUNCTIONS; ALGAN/GAN HEMTS; GALLIUM NITRIDE; MODFETS; PERFORMANCE; BREAKDOWN; DEVICES AB Junction field effect transistors (JFET) were fabricated on a GaN epitaxial structure grown by metal organic chemical vapor deposition. The DC and microwave characteristics, as well as the high temperature performance of the devices were studied. These devices exhibited excellent pinch-off and a breakdown voltage that agreed with theoretical predictions. An extrinsic transconductance (g(m)) of 48 mS/mm was obtained with a maximum drain current (I-D) of 270 mA/mm The microwave measurement showed an f(T) of 6 GHz and an f(max) of 12 GHz. Both the l(D) and the g(m) were found to decrease with increasing temperature, possibly due to lower electron mobility at elevated temperatures. These JFETs exhibited a significant current reduction after a high drain bias was applied, which was attributed to a partially depleted channel caused by trapped electrons in the semi-insulating GaN buffer layer. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Albuquerque, NM 87106 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Off Naval Res, Arlington, VA 22217 USA. RP Zhang, L (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 21 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 2000 VL 5 SU 1 BP art. no. EP W4.9 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600054 ER PT J AU Crawford, MH Han, J Banas, MA Myers, SM Petersen, GA Figiel, JJ AF Crawford, MH Han, J Banas, MA Myers, SM Petersen, GA Figiel, JJ TI Optical spectroscopy of InGaN epilayers in the low indium composition regime SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID MULTIPLE-QUANTUM WELLS; GAN; PHOTOLUMINESCENCE AB Photoluminescence (PL) spectroscopy was carried out on a series of Si-doped bulk InGaN films in the law indium(In) composition regime. Room temperature PL showed a factor of 25 increase in integrated intensity as the In composition was increased from 0 to 0.07. Temperature dependent PL data was fit to an Arrhenius equation to reveal an increasing activation energy for thermal quenching of the PL intensity as the In composition is increased. Time resolved PL measurements revealed that only the sample with highest In (x=0.07) showed a strong spectral variation in decay time across the T=4K PL resonance, indicative of recombination from localized states at low temperatures. The decay times at room temperature were non-radiatively dominated for all films, and the room temperature (non-radiative) decay times increased with increasing In, from 50-230 psec for x=0-0.07. Our data demonstrate that non-radiative recombination is less effective with increasing in composition. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Crawford, MH (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 17 TC 1 Z9 1 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 2000 VL 5 SU 1 AR W11.41 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600099 ER PT J AU Liliental-Weber, Z Benamara, M Swider, W Washburn, J Grzegory, I Porowski, S Dupuis, RD Eiting, CJ AF Liliental-Weber, Z Benamara, M Swider, W Washburn, J Grzegory, I Porowski, S Dupuis, RD Eiting, CJ TI Mg segregation, difficulties of P-doping in GaN SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID GAN(0001); CRYSTALS AB Transmission electron microscopy has been used to study defects formed in Mg-doped GaN crystals. Three types of crystals have been studied: bulk crystals grown by a high pressure and high temperature process with Mg added to the Ga solution and two types of crystals grown by metal-organic chemical vapor deposition (MOCVD) where Mg was either delta-doped or continuously doped. Spontaneous ordering was observed in bulk crystals. The ordering consists of Mg rich planar defects on basal planes separated by 10.4 nm and occurs only for growth in the N to Ga polar direction (000 (1) over bar N polarity). These planar defects exhibit the characteristics of stacking faults with a shift vector of a 1/3 [1 (1) over bar 00] +c/2 but some other features identify these defects as inversion domains. Different type of defects were formed on the opposite site of the crystal (Ga to N polar direction). where the growth rate is also an order of magnitude faster compared to the growth with N-polarity. These defects are three-dimensional: pyramidal and rectangular, empty inside with Mg segregation on internal surfaces. The same types of defects seen for the two growth polarities in the bulk crystals were also observed in the MOCVD grown GaN samples with Mg delta doping, but were not observed in the crystals where Mg was added continuously. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Polish Acad Sci, High Pressure Res Ctr Unipress, Warsaw, Poland. 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 0 Z9 0 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 2000 VL 5 SU 1 AR W9.7 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600070 ER PT J AU Lozykowski, HJ Jadwisienczak, WM Brown, I AF Lozykowski, HJ Jadwisienczak, WM Brown, I TI Photoluminescence and cathodoluminescence of GaN doped with Pr SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID RED-LIGHT EMISSION; ELECTROLUMINESCENCE; LUMINESCENCE AB In this paper we have reported the observation of visible photoluminescence (PL) and cathodoluminescence (CL) of Pr implanted in GaN. The implanted samples were given isochronal thermal annealing treatments at a temperature of 1100 degrees C in NH3, N-2, Ar-2, and in forming gas N-2 + H-2, at atmospheric pressure to recover implantation damages and activate the rare earth ions. The sharp characteristic emission lines corresponding to Pr3+ intra-3f(n) -shell transitions are resolved in the spectral range from 350 nm to 1150 nm and observed over the temperature range of 12 K-335 K. The PL and CL decay kinetics measurement was performed for P-3(1), P-3(0) and D-1(2) levels. C1 Ohio Univ, Stock Ctr, Sch Elect Engn & Comp Sci, Athens, OH 45701 USA. Ohio Univ, Stock Ctr, Condensed Matter & Surface Sci Program, Athens, OH 45701 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Nicholas Copernicus Univ, Inst Phys, Lab Solid State Optoelect, PL-87400 Torun, Poland. RP Lozykowski, HJ (reprint author), Ohio Univ, Stock Ctr, Sch Elect Engn & Comp Sci, Athens, OH 45701 USA. NR 10 TC 1 Z9 1 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 2000 VL 5 SU 1 AR W11.64 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600113 ER PT J AU Pearton, SJ Cho, H Ren, F Chyi, JI Han, J Wilson, RG AF Pearton, SJ Cho, H Ren, F Chyi, JI Han, J Wilson, RG TI Properties and effects of hydrogen in GaN SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID CHEMICAL-VAPOR-DEPOSITION; P-TYPE GAN; MG; PASSIVATION; ACCEPTORS; DEFECTS; SEMICONDUCTORS; COMPENSATION; ACTIVATION; ALN AB The status of understanding of the behavior of hydrogen in GaN and related materials is reviewed. In particular, we discuss the amount of residual hydrogen in MOCVD-grown device structures such as heterojunction bipolar transistors, thyristors and p-i-n diodes intended for high power, high temperature applications. In these structures, the residual hydrogen originating from the growth precursors decorates Mg-doped layers and AlGaN/GaN interfaces. There is a significant difference in the diffusion characteristics and thermal stability of implanted hydrogen between n- and p-GaN, due to the stronger affinity of hydrogen to pair with acceptor dopants and possibly to the difference in H-2 formation probability. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Natl Cent Univ, Dept Elect Engn, Chungli 32054, Taiwan. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Pearton, SJ (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. RI Chyi, Jen-Inn/A-1799-2016 NR 35 TC 0 Z9 0 U1 0 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 2000 VL 5 SU 1 AR W10.6 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600075 ER PT J AU Wampler, WR Barbour, JC Seager, CH Myers, SM Wright, AF Han, J AF Wampler, WR Barbour, JC Seager, CH Myers, SM Wright, AF Han, J TI Lattice location of deuterium in plasma and gas charged Mg doped GaN SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MA SP Mat Res Soc ID CHEMICAL-VAPOR-DEPOSITION; ELECTRON BEAM IRRADIATION AB We have used ion channeling to examine the lattice configuration of deuterium in Mg doped GaN grown by MOCVD. The deuterium is introduced by exposure to gas phase or ECR plasmas. A density functional approach including lattice relaxation, was used to calculate total energies for various locations and charge states of hydrogen in the wurtzite Mg doped GaN lattice. Results of channeling measurements are compared with channeling simulations for hydrogen at lattice locations predicted by density functional theory. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wampler, WR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 18 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 2000 VL 5 SU 1 AR W10.7 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600076 ER PT J AU Zhang, AP Dang, G Ren, F Cao, XA Cho, H Lambers, ES Pearton, SJ Shul, RJ Zhang, L Baca, AG Hickman, R Van Hove, JM AF Zhang, AP Dang, G Ren, F Cao, XA Cho, H Lambers, ES Pearton, SJ Shul, RJ Zhang, L Baca, AG Hickman, R Van Hove, JM TI High density plasma damage induced in n-GaN Schottky diodes using Cl-2/Ar discharges SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article; Proceedings Paper CT Symposium on GaN and Related Alloys Held at the MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MASSACHUSETTS SP Mat Res Soc ID FIELD-EFFECT TRANSISTORS; ETCHING-INDUCED DAMAGE; TEMPERATURE; NOISE AB The effects of de chuck self-bias and high density source power (which predominantly control ion energy and ion flux, respectively) on the electrical properties of n-GaN Schottky diodes exposed to Inductively Coupled Plasma of Cl-2/Ar were examined. Both parameters were found to influence the diode performance, by reducing the reverse breakdown voltage and Schottky barrier height. All plasma conditions were found to produce a nitrogen-deficient surface, with a typical depth of the non-stoichiometry being similar to 500 Angstrom. Post-etch annealing was found to partially restore the diode characteristics. C1 Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. SVT Associates, Eden Prairie, MN 55344 USA. RP Zhang, AP (reprint author), Univ Florida, Dept Chem 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 2000 VL 5 SU 1 AR W11.66 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 368DZ UT WOS:000090103600115 ER PT S AU Sheehy, B Martin, JDD Clatterbuck, TO Kim, DW DiMauro, LF Agostini, P Schafer, KJ Gaarde, MB Kulander, KC AF Sheehy, B Martin, JDD Clatterbuck, TO Kim, DW DiMauro, LF Agostini, P Schafer, KJ Gaarde, MB Kulander, KC BE DiMauro, LF Freeman, RR Kulander, KC TI Strong field atomic physics in the mid-infrared SO MULTIPHOTON PROCESSES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 8th International Conference on Multiphoton Processes (ICOMP VIII) CY OCT 03-08, 1999 CL MONTEREY, CA SP Univ Calif Davis, Dept Appl Sci, Lawrence Livermore Natl Lab, Phys Directorate, Natl Sci Fdn, Spectra Phys & Posit Light Corp ID ORDER HARMONIC-GENERATION; PULSE GENERATION; TUNNELING LIMIT; COHERENT; FEMTOSECOND; IONIZATION; LASERS AB We examine strong field atomic physics in a wavelength region (3-4 microns) where very little work has previously been done. The soft photon energy allows the exploration of one-electron atoms with low binding energies (alkali metals). We find that photoionization spectra differ from rare gas studies at shorter wavelengths due to more complex ion core potentials. Harmonic generation is studied, and we find that harmonic bandwidths are consistent with theory and the possibility of compression to pulse widths much shorter than that of the driving pulse. Harmonic yields in the visible and UV are sufficient for a complete study of their amplitude and phase characteristics. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Sheehy, B (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 17 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 1-56396-946-7 J9 AIP CONF PROC PY 2000 VL 525 BP 59 EP 69 PG 11 WC Optics; Physics, Applied; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA BQ66W UT WOS:000089140300006 ER PT S AU Zweiback, J Smith, RA Yanovsky, VP Cowan, TE Hays, G Wharton, KB Ditmire, T AF Zweiback, J Smith, RA Yanovsky, VP Cowan, TE Hays, G Wharton, KB Ditmire, T BE DiMauro, LF Freeman, RR Kulander, KC TI Nuclear fusion from Coulomb explosions of D-2 clusters ionized by a femtosecond laser SO MULTIPHOTON PROCESSES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 8th International Conference on Multiphoton Processes (ICOMP VIII) CY OCT 03-08, 1999 CL MONTEREY, CA SP Univ Calif Davis, Dept Appl Sci, Lawrence Livermore Natl Lab, Phys Directorate, Natl Sci Fdn, Spectra Phys & Posit Light Corp ID X-RAY-EMISSION; ATOMIC CLUSTERS; IRRADIATION; IONIZATION; DYNAMICS; FIELDS AB Recent experiments on the interaction of intense, ultrafast pulses with large van der Weals bonded clusters have shown that these clusters can explode with substantial kinetic energy. Producing Coulomb explosions in deuterium clusters with a 35 fs laser pulse, we have accelerated ions to sufficient kinetic energy to drive DD nuclear fusion. By diagnosing the fusion yield through measurements of 2.45 MeV fusion neutrons, we have measured the production of over 10(4) neutrons per laser shot when 100 mJ of laser energy is used. C1 Univ Calif Lawrence Livermore Natl Lab, Laser Program L477, Livermore, CA 94550 USA. RP Zweiback, J (reprint author), Univ Calif Lawrence Livermore Natl Lab, Laser Program L477, Livermore, CA 94550 USA. RI Cowan, Thomas/A-8713-2011 OI Cowan, Thomas/0000-0002-5845-000X NR 23 TC 3 Z9 3 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 1-56396-946-7 J9 AIP CONF PROC PY 2000 VL 525 BP 534 EP 543 PG 10 WC Optics; Physics, Applied; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA BQ66W UT WOS:000089140300051 ER PT S AU Cornacchia, M AF Cornacchia, M BE DiMauro, LF Freeman, RR Kulander, KC TI The coherent light source project at SLAC SO MULTIPHOTON PROCESSES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 8th International Conference on Multiphoton Processes (ICOMP VIII) CY OCT 03-08, 1999 CL MONTEREY, CA SP Univ Calif Davis, Dept Appl Sci, Lawrence Livermore Natl Lab, Phys Directorate, Natl Sci Fdn, Spectra Phys & Posit Light Corp ID FREE-ELECTRON-LASER; AMPLIFIED SPONTANEOUS EMISSION; HIGH-GAIN REGIME AB Advances in the physics and technology of photo-injectors, linear accelerators, insertion devices and free-electron lasers make it now possible to generate coherent radiation in the x-ray region by means of the Self-Amplified-Spontaneous-Emission (SASE) process. Th is radiation has much higher brightness, shorter pulses and coherence than present 3(rd) generation sources. The status of the physics and technology involved in a radiation source based on SASE is reviewed. The design status of a 1.5 Angstrom SASE-FEL at SLAG, called the Linac Coherent Light Source (LCLS), is described. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Cornacchia, M (reprint author), Stanford Linear Accelerator Ctr, POB 4349, Stanford, CA 94309 USA. NR 27 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 1-56396-946-7 J9 AIP CONF PROC PY 2000 VL 525 BP 623 EP 631 PG 9 WC Optics; Physics, Applied; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA BQ66W UT WOS:000089140300059 ER PT S AU Maudlin, PJ Bingert, JF Gray, GT Garrett, RK AF Maudlin, PJ Bingert, JF Gray, GT Garrett, RK BE Robertson, IM Lassila, DH Devincre, B Phillips, R TI Symmetry investigation of textured polycrystal properties (invited) SO MULTISCALE PHENOMENA IN MATERIALS-EXPERIMENTS AND MODELING SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Phenomena in Materials-Experiments and Modeling at the 1999 MRS Fall Meeting CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Lawrence Livermore Natl Lab, Univ Illinois, CNRS, ONERA, Brown Univ, Mat Res Soc AB Tantalum plate and rod materials that demonstrate mild-to-strong anisotropic plastic flow during large deformation are analyzed in terms of tensorial property symmetry. Texture interrogations of these materials reveal duplex orientation components that have implications with regard to the symmetry realized during plastic deformation; specifically these materials show less symmetry than one would expect from a cursory examination of the texture. Mesoscale polycrystal simulations are performed to probe a general shape for the yield surface function based on a discrete orientation distribution representation of the material texture and previously established single-crystal deformation modes. The yield surface shape is mathematically represented in terms of second and higher-order tensors. A plastic compliance analysis is presented and applied to graphically map the deformation symmetry contained in these tensors for both ideal and real materials. Compliance results are shown to be consistent with finite element simulations of r-value specimens loaded in uniaxial tension. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Maudlin, PJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 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 1-55899-486-6 J9 MATER RES SOC SYMP P PY 2000 VL 578 BP 3 EP 14 PG 12 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ74R UT WOS:000089399800001 ER PT S AU Horstemeyer, MF Baskes, MI AF Horstemeyer, MF Baskes, MI BE Robertson, IM Lassila, DH Devincre, B Phillips, R TI Strain tensors at the atomic scale SO MULTISCALE PHENOMENA IN MATERIALS-EXPERIMENTS AND MODELING SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Phenomena in Materials-Experiments and Modeling at the 1999 MRS Fall Meeting CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Lawrence Livermore Natl Lab, Univ Illinois, CNRS, ONERA, Brown Univ, Mat Res Soc ID LATTICE-DEFECTS; HYDROGEN; NICKEL AB Almansi and Green strain tensors are developed for use in large deformation molecular dynamics/statics simulations that employ Embedded Atom Method (EAM) potentials for metals. The strain tensors are formulated with respect to the deformation gradient. A scalar potential function is used with a weighting function that is dependent upon a cutoff radius for the deformation gradient. For a homogeneous or inhomogeneous deformation, a cutoff distance of one lattice parameter can be used to approximate local strain level. Inhomogeneous deformation reveals different results for Almansi and Green strain tensors indicating that the small strain assumption cannot be used to determine large atomic strains. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Horstemeyer, MF (reprint author), Sandia Natl Labs, MS9405, Livermore, CA 94550 USA. OI Horstemeyer, Mark/0000-0003-4230-0063 NR 6 TC 8 Z9 9 U1 1 U2 9 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-486-6 J9 MATER RES SOC SYMP P PY 2000 VL 578 BP 15 EP 20 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ74R UT WOS:000089399800002 ER PT S AU Hsiung, LM Lassila, DH AF Hsiung, LM Lassila, DH BE Robertson, IM Lassila, DH Devincre, B Phillips, R TI Dislocation multiplication in the early stage of deformation in Mo single crystals SO MULTISCALE PHENOMENA IN MATERIALS-EXPERIMENTS AND MODELING SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Phenomena in Materials-Experiments and Modeling at the 1999 MRS Fall Meeting CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Lawrence Livermore Natl Lab, Univ Illinois, CNRS, ONERA, Brown Univ, Mat Res Soc AB Initial dislocation structure in annealed high-purity Mo single crystals and deformation substructure in a crystal subjected to 1% compression have been examined and studied using transmission electron microscopy (TEM) techniques in order to investigate dislocation multiplication mechanisms in the early stage of plastic deformation. The initial dislocation density is in a range of 10(6) similar to 10(7) cm(2), and the dislocation structure is found to contain many grown-in superjogs along dislocation lines. The dislocation density increases to a range of 10(8) similar to 10(9) cm(2), and the average jog height is also found to increase after compressing for a total strain of 1%. It is proposed that the preexisting jogged screw dislocations can act as (multiple) dislocation multiplication sources when deformed under quasi-static conditions. The jog height can increase by stress-induced jog coalescence, which takes place via the lateral migration (drift) of superjogs driven by unbalanced line-tension partials acting on link segments of unequal lengths. The coalescence of superjogs results in an increase of both link length and jog height. Applied sheer stress begins to push each link segment to precede dislocation multiplication when link length and jog height are greater than critical lengths. This "dynamic" dislocation multiplication source is suggested to be crucial for the dislocation multiplication in the early stage of plastic deformation in Mo. C1 Univ Calif Lawrence Livermore Natl Lab, Div Mat Sci & Technol, Livermore, CA 94551 USA. RP Hsiung, LM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Div Mat Sci & Technol, L-369,POB 808, Livermore, CA 94551 USA. NR 4 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 1-55899-486-6 J9 MATER RES SOC SYMP P PY 2000 VL 578 BP 119 EP 124 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ74R UT WOS:000089399800017 ER PT S AU Wickham, LK Schwarz, KW Stolken, JS AF Wickham, LK Schwarz, KW Stolken, JS BE Robertson, IM Lassila, DH Devincre, B Phillips, R TI Dislocation forest interactions: Simulation and prediction SO MULTISCALE PHENOMENA IN MATERIALS-EXPERIMENTS AND MODELING SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Phenomena in Materials-Experiments and Modeling at the 1999 MRS Fall Meeting CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Lawrence Livermore Natl Lab, Univ Illinois, CNRS, ONERA, Brown Univ, Mat Res Soc AB Using linear elastic dislocation dynamics simulations, we show that junction formation between dislocations from various interacting slip systems can be predicted by a simple self-energy calculation. We find that this prediction is robust: dislocation curvature and external stress produce little change in the simulation results for junction formation. One key to this success appears to be a separation of timescales, where movement of the far away dislocation arms (under, for example, external stress) is typically slow compared to the process of making a junction. The self-energy calculation we describe gives a rule for dislocation encounters which should allow a considerable saving in computational effort, allowing one to impose correct interaction outcomes without calculating the interactions in detail. We also find that dislocations often come together under attraction without forming a junction. The resulting "cross-linked" state provides an additional type of connection between dislocations. We include preliminary results on the persistence of junctions and cross-linked states under stress. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Wickham, LK (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 8 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 1-55899-486-6 J9 MATER RES SOC SYMP P PY 2000 VL 578 BP 125 EP 130 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ74R UT WOS:000089399800018 ER PT S AU Hartley, CS AF Hartley, CS BE Robertson, IM Lassila, DH Devincre, B Phillips, R TI Single crystal elastic moduli of disordered cubic alloys SO MULTISCALE PHENOMENA IN MATERIALS-EXPERIMENTS AND MODELING SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Phenomena in Materials-Experiments and Modeling at the 1999 MRS Fall Meeting CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Lawrence Livermore Natl Lab, Univ Illinois, CNRS, ONERA, Brown Univ, Mat Res Soc ID POLYCRYSTALLINE AB A review of the relationship between elastic moduli and interatomic force constants precedes the description of a method for determining the composition dependence of single crystal elastic moduli of disordered alloys having the face-centered cubic structure. The method treats the alloy as a virtual crystal, characterized by an effective pair potential between atoms. Results of calculations are presented using experimental data on Cu-rich Cu-Al alloys. C1 US DOE, Germantown, MD 20874 USA. RP Hartley, CS (reprint author), US DOE, SC-131, Germantown, MD 20874 USA. NR 24 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 1-55899-486-6 J9 MATER RES SOC SYMP P PY 2000 VL 578 BP 279 EP 284 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ74R UT WOS:000089399800041 ER PT S AU Somerday, BP Pattillo, PD Horstemeyer, MF Baskes, MI AF Somerday, BP Pattillo, PD Horstemeyer, MF Baskes, MI BE Robertson, IM Lassila, DH Devincre, B Phillips, R TI Atomistic modeling of void growth and coalescence in Ni+H SO MULTISCALE PHENOMENA IN MATERIALS-EXPERIMENTS AND MODELING SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Phenomena in Materials-Experiments and Modeling at the 1999 MRS Fall Meeting CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Lawrence Livermore Natl Lab, Univ Illinois, CNRS, ONERA, Brown Univ, Mat Res Soc ID EMBEDDED-ATOM METHOD; DUCTILE FRACTURE; LATTICE-DEFECTS; HYDROGEN; NICKEL; METALS AB Finite strain rate atomistic simulations were conducted on Ni and Ni+H lattices containing voids to better understand the dislocation-scale mechanisms of void growth and coalescence and how hydrogen affects these damage processes. Void growth is governed by dislocations that nucleate at the void surface to transport mass away from the void as well as dislocations arriving at the void from the lattice exterior to deposit vacancies and accommodate void-surface expansion. Hydrogen can retard void growth when large local hydrogen concentrations impede dislocation nucleation and propagation at the void surface. The formation of hydrogen gas molecules in the void interior does not necessarily aid void growth. Pressure in small voids may be mitigated by the mutual interaction of hydrogen molecules and the interaction of molecules with the void surface. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Somerday, BP (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 969,MS 9402, Livermore, CA 94550 USA. OI Horstemeyer, Mark/0000-0003-4230-0063 NR 18 TC 3 Z9 3 U1 2 U2 6 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-486-6 J9 MATER RES SOC SYMP P PY 2000 VL 578 BP 333 EP 338 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ74R UT WOS:000089399800049 ER PT S AU Verdier, M AF Verdier, M BE Lepinoux, J Maziere, D Pontikis, V Saada, G TI Conjunction of experimental approaches: The relevant choice SO MULTISCALE PHENOMENA IN PLASTICITY: FROM EXPERIMENTS TO PHENOMENOLOGY, MODELLING AND MATERIALS SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES E, APPLIED SCIENCES LA English DT Proceedings Paper CT Conference of the NATO-Advanced-Study-Institute on Multiscale Phenomena in Plasticity - From Experiments to Phenomenology CY SEP 08-19, 1999 CL OURANOUPOLIS, GREECE SP NATO ID MECHANICAL-PROPERTIES; ALLOYS; ALUMINUM; RECOVERY AB This contribution presents different experimental techniques which are pertinent to address some problems in the physics of deformation of fee metals, i.e. establishing the relationships between microstructural features and mechanical behaviour of the material. There are two examples that will best illustrate these approaches. The first one deals with the thermal stability during static recovery of dislocation structures obtained by cold rolling Al-2.5Mg alloys to large strain. TEM observations allow to characterize spatial arrangement of dislocations, but do not bring enough pertinent information concerning the driving force of recovery. We used different techniques in conjunction to characterize dislocation structures (resistivity, X-Ray peak broadening, calorimetry) to deduce relevant mesoscopic parameters (i.e. at the scale of the dislocation microstructure in a grain). The second example deals with the mechanisms of plastic deformation in metallic nanocomposites. We use model materials (multilayers) and apply complementary techniques to evidence the plastic flow in these structures. C1 Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. RP Verdier, M (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, MS K765, Los Alamos, NM 87545 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0168-132X BN 0-7923-6251-9 J9 NATO ADV SCI I E-APP PY 2000 VL 367 BP 227 EP 236 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Physics, Condensed Matter SC Materials Science; Physics GA BR46T UT WOS:000166546400018 ER PT S AU Bulatov, VV AF Bulatov, VV BE Lepinoux, J Maziere, D Pontikis, V Saada, G TI Connecting the micro to the mesoscale: Review and specific examples SO MULTISCALE PHENOMENA IN PLASTICITY: FROM EXPERIMENTS TO PHENOMENOLOGY, MODELLING AND MATERIALS SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES E, APPLIED SCIENCES LA English DT Proceedings Paper CT Conference of the NATO-Advanced-Study-Institute on Multiscale Phenomena in Plasticity - From Experiments to Phenomenology CY SEP 08-19, 1999 CL OURANOUPOLIS, GREECE SP NATO ID ATOMIC-STRUCTURE; DISLOCATION; SIMULATIONS; SILICON; PLASTICITY; PLANES; COPPER; GLIDE; KINKS C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Bulatov, VV (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM bulatov1@llnl.gov NR 17 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0168-132X BN 0-7923-6252-7 J9 NATO ADV SCI I E-APP PY 2000 VL 367 BP 259 EP 269 PG 11 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Physics, Condensed Matter SC Materials Science; Physics GA BR46T UT WOS:000166546400020 ER PT S AU Phillpot, SR AF Phillpot, SR BE Lepinoux, J Maziere, D Pontikis, V Saada, G TI An introduction to the molecular-dynamics simulation of materials SO MULTISCALE PHENOMENA IN PLASTICITY: FROM EXPERIMENTS TO PHENOMENOLOGY, MODELLING AND MATERIALS SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES E, APPLIED SCIENCES LA English DT Proceedings Paper CT Conference of the NATO-Advanced-Study-Institute on Multiscale Phenomena in Plasticity - From Experiments to Phenomenology CY SEP 08-19, 1999 CL OURANOUPOLIS, GREECE SP NATO ID EMBEDDED-ATOM-METHOD; METALS; SILICON AB The fundamental principles of the molecular-dynamics (MD) simulation method are reviewed. The ability of MD to identify and elucidate mechanisms, provide insight and to determine trends in physical properties is discussed. The limitations of MD are also discussed, particularly with regards to limits on materials specificity and to the short times and small length scales accessible. A brief discussion of approaches to linking MD to simulation methods at other length and time scales is given. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Phillpot, SR (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 0 Z9 0 U1 0 U2 3 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0168-132X BN 0-7923-6251-9 J9 NATO ADV SCI I E-APP PY 2000 VL 367 BP 271 EP 280 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Physics, Condensed Matter SC Materials Science; Physics GA BR46T UT WOS:000166546400021 ER PT S AU Rasmussen, T AF Rasmussen, T BE Lepinoux, J Maziere, D Pontikis, V Saada, G TI Cross slip in the face centred cubic structure: An atomistic approach SO MULTISCALE PHENOMENA IN PLASTICITY: FROM EXPERIMENTS TO PHENOMENOLOGY, MODELLING AND MATERIALS SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES E, APPLIED SCIENCES LA English DT Proceedings Paper CT Conference of the NATO-Advanced-Study-Institute on Multiscale Phenomena in Plasticity - From Experiments to Phenomenology CY SEP 08-19, 1999 CL OURANOUPOLIS, GREECE SP NATO ID FCC CRYSTALS; ENERGETICS; DISLOCATIONS; SIMULATIONS; PARAMETERS; PLASTICITY; COPPER; METALS; MODEL C1 Univ Calif Los Alamos Natl Lab, Div Theoret T12, Los Alamos, NM 87545 USA. RP Rasmussen, T (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret T12, Los Alamos, NM 87545 USA. NR 25 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0168-132X BN 0-7923-6251-9 J9 NATO ADV SCI I E-APP PY 2000 VL 367 BP 281 EP 292 PG 12 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Physics, Condensed Matter SC Materials Science; Physics GA BR46T UT WOS:000166546400022 ER PT S AU Honda, S Modine, FA Haynes, TE Meldrum, A Budai, JD Song, KJ Thompson, JR Boatner, LA AF Honda, S Modine, FA Haynes, TE Meldrum, A Budai, JD Song, KJ Thompson, JR Boatner, LA BE Komarneni, S Parker, JC Hahn, H TI The formation of high-coercivity, oriented, nanophase cobalt precipitates in Al2O3 single crystals by ion implantation SO NANOPHASE AND NANOCOMPOSITE MATERIALS III SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nanophase and Nanocomposite Materials III held at the 1999 MRS Fall Meeting CY NOV 29-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID SAPPHIRE AB Ion-implantation and thermal-processing methods have been used to form nanophase magnetic precipitates of metallic cobalt that are embedded in the near-surface region of single crystals of Al2O3. The Co precipitates are isolated, single-crystal particles that are crystallographically oriented with respect to the host Al2O3 lattice. Embedded nanophase Co precipitates were formed by the implantation of Co+ at an energy of 140 keV and a dose of 8 x 10(16) ions/cm(2) followed by annealing in a reducing atmosphere. The implanted/annealed Co depth profile, particle size distributions and shapes, and the orientational relationship between the nanophase precipitates and the host crystal lattice were determined using RBS/channeling, transmission electron microscopy, and x-ray diffraction. Magneto-optical effects arising from Co precipitates formed in the near-surface region of Al2O3 were observed and characterized using magnetic circular dichroism. Magnetic properties of the Co-particle/host nanocomposites were investigated in the temperature range of 77 to 295 K in applied fields of up to 10 kG using a superconducting, quantum interference device (SQUID) magnetometer. Implantation of the Co particles by Pt or Xe ions produced a large anisotropic increase in their coercivity. Accordingly these magnetic nanoparticle systems may be of interest for magnetic data storage applications. Details of the magnetic properties of the Co/Al2O3 nanocomposites including their retentivity, coercivity, saturation field, and magnetic anisotropy are presented. 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 6 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 1-55899-489-0 J9 MATER RES SOC SYMP P PY 2000 VL 581 BP 71 EP 76 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BQ34P UT WOS:000088059300012 ER PT S AU Schulz, D Ribelin, R Wu, X Jones, KM Matson, RJ Curtis, CJ Gessert, T Ginley, DS AF Schulz, D Ribelin, R Wu, X Jones, KM Matson, RJ Curtis, CJ Gessert, T Ginley, DS BE Komarneni, S Parker, JC Hahn, H TI Solar cell contacts using nano-sized dispersions SO NANOPHASE AND NANOCOMPOSITE MATERIALS III SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nanophase and Nanocomposite Materials III held at the 1999 MRS Fall Meeting CY NOV 29-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID CDTE; TE AB Nano-sized dispersions have been employed as precursor inks for the spray deposition of contacts to both Si and CdTe materials. In the case of Si, nano-sized Al particles (nano-Al) were dispersed and spray deposited onto p-type Si. Annealing above the eutectic temperature causes alloy formation yielding a p+ layer with p similar to 10(-4) Omega(.)cm. For CdTe, nano-sized Te particles (nano-Te) were dispersed and sprayed onto CdTe/CdS/SnO2/glass heterostructures. Contact to the CdTe layer occurred during a 30 min anneal in He (T = 215 to 255 degrees C). These solar cells were finished by spin-coating the Te layer with Ag paint and subsequently annealing in air (100 degrees C / 1 h). This approach produces solar cells with open circuit voltages (V-oc) from 720 to 800 mV, short circuit current densities (J(sc)) from 18 to 20 mA/cm(2) and efficiencies up to 10.3%. The performance of these cells was similar to those produced using the standard NREL contact. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Schulz, D (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 4 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 1-55899-489-0 J9 MATER RES SOC SYMP P PY 2000 VL 581 BP 157 EP 162 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BQ34P UT WOS:000088059300025 ER PT S AU Kadavanich, AV Kippeny, T Erwin, M Rosenthal, SJ Pennycook, SJ AF Kadavanich, AV Kippeny, T Erwin, M Rosenthal, SJ Pennycook, SJ BE Komarneni, S Parker, JC Hahn, H TI Z contrast STEM imaging and EELS of CdSe nanocrystals: Towards the analysis of individual nanocrystal surfaces SO NANOPHASE AND NANOCOMPOSITE MATERIALS III SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nanophase and Nanocomposite Materials III held at the 1999 MRS Fall Meeting CY NOV 29-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID LIGHT-EMITTING-DIODES; SEMICONDUCTING POLYMER; SPECTROSCOPY AB We have applied Atomic Number Contrast Scanning Transmission Electron Microscopy (Z-Contrast STEM) and STEM/EELS (Electron Energy Loss Spectroscopy) towards the study of colloidal CdSe semiconductor nanocrystals embedded in MEH-PPV polymer films. Z-Contrast images are direct projections of the atomic structure. Hence they can be interpreted without the need for sophisticated image simulation and the image intensity is a direct measure of the thickness of a nanocrystal. Our thickness measurements are in agreement with the predicted faceted shape of these nanocrystals. Our unique 1.3 Angstrom resolution STEM has successfully resolved the sublattice structure of these CdSe nanocrystals. In [010] projection (the polar axis in the image plane) we can distinguish Se atom columns from Cd columns. EELS measurements on individual nanocrystals indicate a significant amount (equivalent to 0.5-1 surface monolayers) of oxygen on the nanocrystals, despite processing in an inert atmosphere. Spatially resolved measurements at 7 Angstrom resolution suggest a surface oxide layer. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Vanderbilt Univ, Dept Chem, Nashville, TN 37235 USA. RP Kadavanich, AV (reprint author), Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. NR 14 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 1-55899-489-0 J9 MATER RES SOC SYMP P PY 2000 VL 581 BP 503 EP 509 PG 7 WC Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BQ34P UT WOS:000088059300080 ER PT B AU Dixon, D Cummings, P Hess, K AF Dixon, D Cummings, P Hess, K BE Roco, MC Williams, RS Alivisatos, P TI Investigative tools: Theory, modeling, and simulation SO NANOTECHNOLOGY RESEARCH DIRECTIONS: IWGN WORKSHOP REPORT: VISION FOR NANOTECHNOLOGY R&D IN THE NEXT DECADE LA English DT Proceedings Paper CT Workshop on Nanotechnology Research Directions CY JAN 27-29, 1999 CL ARLINGTON, VA SP Interagency Working Grp Nanosci, Engn, Technol, Natl Sci & Technol Council ID DYNAMICS SIMULATIONS; DNA C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Dixon, D (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999,MS K1-83, Richland, WA 99352 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6220-9 PY 2000 BP 25 EP 43 PG 19 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA BQ47G UT WOS:000088436900003 ER PT J AU Brim, H McFarlan, SC Fredrickson, JK Minton, KW Zhai, M Wackett, LP Daly, MJ AF Brim, H McFarlan, SC Fredrickson, JK Minton, KW Zhai, M Wackett, LP Daly, MJ TI Engineering Deinococcus radiodurans for metal remediation in radioactive mixed waste environments SO NATURE BIOTECHNOLOGY LA English DT Article DE mercuric reductase; bioremediation ID ESCHERICHIA-COLI; RECOMBINATION; RESISTANCE; PURIFICATION; REDUCTION; PLASMID; GENE AB We have developed a radiation resistant bacterium for the treatment of mixed radioactive wastes containing ionic mercury. The high cost of remediating radioactive waste sites from nuclear weapons production has stimulated the development of bioremediation strategies using Deinococcos radiodurans, the most radiation resistant organism known. As a frequent constituent of these sites is the highly toxic ionic mercury (Hg) (II), we have generated several D. radiodurans strains expressing the cloned Hg (II) resistance gene (merA) from Escherichia coli strain BL308. We designed four different expression vectors for this purpose, and compared the relative advantages of each, The strains were shown to grow in the presence of both radiation and ionic mercury at concentrations well above those found in radioactive waste sites, and to effectively reduce Hg (II) to the less toxic volatile elemental mercury. We also demonstrated that different gene clusters could be used to engineer D. radiodurans for treatment of mixed radioactive wastes by developing a strain to detoxify both mercury and toluene. These expression systems could provide models to guide future D. radiodurans engineering efforts aimed at integrating several remediation functions into a single host. C1 Uniformed Serv Univ Hlth Sci, Dept Pathol, Bethesda, MD 20814 USA. Univ Minnesota, Biol Proc Technol Inst, Dept Biochem, St Paul, MN 55108 USA. Univ Minnesota, Ctr Biodegradat Res & Informat, Gortner Lab, St Paul, MN 55108 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Daly, MJ (reprint author), Uniformed Serv Univ Hlth Sci, Dept Pathol, 4301 Jones Bridge Rd, Bethesda, MD 20814 USA. NR 34 TC 127 Z9 165 U1 6 U2 69 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1087-0156 J9 NAT BIOTECHNOL JI Nat. Biotechnol. PD JAN PY 2000 VL 18 IS 1 BP 85 EP 90 PG 6 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 273GQ UT WOS:000084699900032 PM 10625398 ER PT J AU Hu, ZL Bonifas, JM Beech, J Bench, G Shigihara, T Ogawa, H Ikeda, S Mauro, T Epstein, EH AF Hu, ZL Bonifas, JM Beech, J Bench, G Shigihara, T Ogawa, H Ikeda, S Mauro, T Epstein, EH TI Mutations in ATP2C1, encoding a calcium pump, cause Hailey-Hailey disease SO NATURE GENETICS LA English DT Article ID YEAST SECRETORY PATHWAY; IDENTIFICATION; GENE; CHROMOSOME; RETICULUM; GOLGI; PMR1; DIFFERENTIATION; TRANSPORT; PEMPHIGUS AB Hailey-Hailey disease (HHD, MIM 16960) is inherited in an autosomal dominant manner and characterized by persistent blisters and erosions of the skin(1). Impaired intercellular adhesion and epidermal blistering also occur in individuals with pemphigus (which is due to autoantibodies directed against desmosomal proteins) and in patients with Darier disease (DD, MIM 124200), which is caused by mutations in a gene encoding a sarco/endoplasmic reticulum (ER)-Golgi calcium pump(2). We report here the identification of mutations in ATP2C1, encoding the human homologue of an ATP-powered pump that sequesters calcium into the Golgi in yeast, in 21 HHD kindreds. Regulation of cytoplasmic calcium is impaired in cultured keratinocytes from HHD patients, and the normal epidermal calcium gradient is attenuated in vivo in HHD patients. Our findings not only provide an understanding of the molecular basis of HHD, but also underscore the importance of calcium control to the functioning of stratified squamous epithelia. C1 San Francisco Gen Hosp, Dept Dermatol, San Francisco, CA 94110 USA. Univ Calif San Francisco, Dept Dermatol, VA Med Ctr, San Francisco, CA 94143 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. Juntendo Univ, Sch Med, Dept Dermatol, Tokyo 113, Japan. RP Epstein, EH (reprint author), San Francisco Gen Hosp, Dept Dermatol, San Francisco, CA 94110 USA. FU NIAMS NIH HHS [AR44341, AR43119] NR 27 TC 304 Z9 329 U1 0 U2 7 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 2000 VL 24 IS 1 BP 61 EP 65 DI 10.1038/71701 PG 5 WC Genetics & Heredity SC Genetics & Heredity GA 271TH UT WOS:000084609200017 PM 10615129 ER PT J AU Ramratnam, B Mittler, JE Zhang, LQ Boden, D Hurley, A Fang, F Macken, CA Perelson, AS Markowitz, M Ho, DD AF Ramratnam, B Mittler, JE Zhang, LQ Boden, D Hurley, A Fang, F Macken, CA Perelson, AS Markowitz, M Ho, DD TI The decay of the latent reservoir of replication-competent HIV-1 is inversely correlated with the extent of residual viral replication during prolonged anti-retroviral therapy SO NATURE MEDICINE LA English DT Article ID ACTIVE ANTIRETROVIRAL THERAPY; RAPID TURNOVER; LIFE-SPAN; IN-VIVO; INFECTION; LYMPHOCYTES AB Replication-competent HIV-1 can be isolated from infected patients despite prolonged plasma virus suppression by anti-retroviral treatment(1-3). Recent studies have identified resting, memory CDC T lymphocytes as a long-lived latent reservoir of HIV-1 (refs. 4,5). Cross-sectional analyses indicate that the reservoir is rather small, between 10(3) and 10(7) cells per patient(5,6). In individuals whose plasma viremia levels are well suppressed by anti-retroviral therapy, peripheral blood mononuclear cells containing replication-competent HIV-1 were found to decay with a mean half-life of approximately 6 months(7), close to the decay characteristics of memory lymphocytes in humans and monkeys(8-10). In contrast, little decay was found in a less-selective patient population(11). We undertook this study to address this apparent discrepancy. Using a quantitative micro-culture assay, we demonstrate here that the latent reservoir decays with a mean half-life of 6.3 months in patients who consistently maintain plasma HIV-1 RNA levels of fewer than 50 copies/ml. Slower decay rates occur in individuals who experience intermittent episodes of plasma viremia. Our findings indicate that the persistence of the latent reservoir of HIV-1 despite prolonged treatment is due not only to its slow intrinsic decay characteristics but also to the inability of current drug regimens to completely block HIV-1 replication. C1 Rockefeller Univ, Aaron Diamond AIDS Res Ctr, New York, NY 10016 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ho, DD (reprint author), Rockefeller Univ, Aaron Diamond AIDS Res Ctr, 455 1st Ave, New York, NY 10016 USA. FU NCRR NIH HHS [RR06555]; NIAID NIH HHS [AI40387, AI41534] NR 25 TC 344 Z9 349 U1 1 U2 4 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1078-8956 J9 NAT MED JI Nat. Med. PD JAN PY 2000 VL 6 IS 1 BP 82 EP 85 PG 4 WC Biochemistry & Molecular Biology; Cell Biology; Medicine, Research & Experimental SC Biochemistry & Molecular Biology; Cell Biology; Research & Experimental Medicine GA 271FJ UT WOS:000084583300040 PM 10613829 ER PT J AU Paulus, MJ Gleason, SS Kennel, SJ Hunsicker, PR Johnson, DK AF Paulus, MJ Gleason, SS Kennel, SJ Hunsicker, PR Johnson, DK TI High resolution X-ray computed tomography: An emerging tool for small animal cancer research SO NEOPLASIA LA English DT Review DE microCT; X-ray; microtomography; animal model ID NUCLEAR MAGNETIC-RESONANCE; TRANSMISSION TOMOGRAPHY; PROSTATE-CANCER; BEAM RECONSTRUCTION; BONE ARCHITECTURE; TRANSGENIC MOUSE; MICROTOMOGRAPHY; CT; SCANNER; MICE AB Dedicated high-resolution small animal imaging systems have recently emerged as important new tools for cancer research. These new imaging systems permit researchers to noninvasively screen animals for mutations or pathologies and to monitor disease progression and response to therapy. One imaging modality, X-ray microcomputed tomography (microCT) shows promise as a cost-effective means for detecting and characterizing soft-tissue structures, skeletal abnormalities, and tumors in live animals. MicroCT systems provide high-resolution images (typically 50 microns or less), rapid data acquisition (typically 5 to 30 minutes), excellent sensitivity to skeletal tissue and good sensitivity to soft tissue, particularly when contrast-enhancing media are employed. The development of microCT technology for small animal imaging is reviewed, and key considerations for designing small animal microCT imaging protocols are summarized. Recent studies on mouse prostate, lung and bone tumor models are overviewed. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Paulus, MJ (reprint author), Oak Ridge Natl Lab, POB 2008,MS 6006, Oak Ridge, TN 37831 USA. NR 75 TC 316 Z9 320 U1 4 U2 49 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1522-8002 J9 NEOPLASIA JI Neoplasia PD JAN-APR PY 2000 VL 2 IS 1-2 BP 62 EP 70 DI 10.1038/sj.neo.7900069 PG 9 WC Oncology SC Oncology GA 305BV UT WOS:000086519700006 PM 10933069 ER PT S AU Chen, H Wyckoff, P AF Chen, H Wyckoff, P BE Falsafi, B Lauria, M TI Simulation studies of gigabit ethernet versus myrinet using real application cores SO NETWORK-BASED PARALLEL COMPUTING, PROCEEDINGS: COMMUNICATION, ARCHITECTURE, AND APPLICATIONS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 4th International Workshop on Communication, Architecture, and Applications for Network-Based Parallel Computing (CANPC 2000) CY JAN 08, 2000 CL TOULOUSE, FRANCE AB Parallel cluster computing projects use a large number of commodity PCs to provide cost-effective computational power to run parallel applications. Because properly load-balanced distributed parallel applications tend to send messages synchronously, minimizing blocking is as crucial a requirement for the network fabric as are those of high bandwidth and low latency. We consider the selection of an optimal, commodity-based, interconnect network technology and topology to provide high bandwidth, low latency, and reliable delivery. Since our network design goal is to facilitate the performance of real applications, we evaluated the performance of myrinet and gigabit ethernet technologies in the context of working algorithms using modeling and simulation tools developed for this work. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Chen, H (reprint author), Sandia Natl Labs, MS 9011,POB 969, Livermore, CA 94551 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-67879-4 J9 LECT NOTES COMPUT SC PY 2000 VL 1797 BP 130 EP 144 PG 15 WC Computer Science, Theory & Methods SC Computer Science GA BT02T UT WOS:000171691200010 ER PT J AU Tirosh, O Sen, CK Roy, S Packer, L AF Tirosh, O Sen, CK Roy, S Packer, L TI Cellular and mitochondrial changes in glutamate-induced HT4 neuronal cell death SO NEUROSCIENCE LA English DT Article DE antioxidants; redox; reactive oxygen species; protein synthesis; intracellular calcium ID CENTRAL-NERVOUS-SYSTEM; ALPHA-LIPOIC ACID; OXIDATIVE STRESS; PERMEABILITY TRANSITION; GLUTATHIONE DEPLETION; MEDIATED APOPTOSIS; REDOX REGULATION; REACTIVE OXYGEN; FREE-RADICALS; CYTOCHROME-C AB Elevated levels of extracellular glutamate are neurotoxic. The cytotoxic property of extracellular glutamate is known to mediate two primary mechanisms, excitotoxicity and excitotoxicity-independent processes. The excitotoxicity-independent pathway was investigated in the current study in a mouse hippocampal-derived HT4 cell line. Exposure of HT4 cells to glutamate for 12h induced loss of cell viability preceded by rapid loss of intracellular reduced glutathione followed by accumulation of intracellular reactive oxygen species, elevation of intracellular Ca2+, progressive loss of mitochondrial membrane potential swelling and loss of mitochondrial outer membrane integrity. Glutamate-induced loss of DNA integrity has been detected. The antioxidants or-tocopherol and trolox, mitochondrial calcium uniporter inhibitor Ruthenium Red and protein synthesis inhibitor cycloheximide all showed protection against glutamate-induced toxicity. None of the protective agents except for or-tocopherol controlled the glutamate-induced reactive oxygen species build-up. However, these cell death regulators prevented the glutamate-induced mitochondrial damage and regulated glutamate-induced increase in intracellular Ca2+. Carbonyl cyanide p-trifluoro-merhoxyphenyl-hydrazone. a mitochondrial uncoupler, partially protected against glutamate-induced cell death and mitochondrial damage, while the mitochondrial ribosomal inhibitor chloramphenicol and extracellular Ca2+ chelator ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid did not protect the cells against glutamate treatment. The results of this study demonstrated that mitochondrial dysfunction was a key event in the excitotoxicity-independent component of neuronal cell death. Reactive oxygen species accumulation and glutathione depletion were prominent in glutamate-treated cells; however, these events were not direct mediators of cell death. (C) 2000 IBRO. Published by Elsevier Science Ltd. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Sen, CK (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Sen, Chandan/A-8762-2013; Roy, sashwati/E-3990-2011 FU NIDDK NIH HHS [DK50430]; NIGMS NIH HHS [GM27345] NR 52 TC 58 Z9 63 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 2000 VL 97 IS 3 BP 531 EP 541 DI 10.1016/S0306-4522(00)00028-2 PG 11 WC Neurosciences SC Neurosciences & Neurology GA 321CT UT WOS:000087437900013 PM 10828535 ER PT S AU Thompson, JR Ossandon, JG Krusin-Elbaum, L Song, KJ Christen, DK Wu, JZ Ullmann, JL AF Thompson, JR Ossandon, JG Krusin-Elbaum, L Song, KJ Christen, DK Wu, JZ Ullmann, JL BE Klamut, J Veal, BW Dabrowski, BM Klumut, PW Kazimierski, M TI Vortex pinning and critical current enhancements in high-T-c superconductors with fission-generated random columnar defects SO NEW DEVELOPMENTS IN HIGH TEMPERATURE SUPERCONDUCTIVITY SE LECTURE NOTES IN PHYSICS LA English DT Proceedings Paper CT 2nd Polish-United States Conference on New Developments in High Temperature Superconductivity CY AUG 18-21, 1998 CL KARPACZ, POLAND ID 0.8 GEV PROTONS; CURRENT-DENSITY; FLUX-CREEP; VORTICES; TAPES; IRRADIATION AB Randomly oriented columnar defects can efficiently increase and stabilize the current density in many high-T-C superconductors. Irradiation with 0.8 GeV protons induces a prompt fission of heavy constituent nuclei, such as Hg, Tl, Pb, and Bi, in the cuprate compounds; then recoiling fragments generate randomly oriented columnar tracks. This markedly enhances the persistent current density J, elevates the irreversibility line to higher fields and temperatures, and reduces the temporal rate of current decay. The associated crystalline disorder depresses Tc by similar to 0.1 - 1K per 1016 proton/cm(2). At optimal proton fluency, J is enhanced by one or more orders of magnitude (compared with unirradiated virgin materials) and the logarithmic decay rate dln(J)/dln(t) is diminished. However, we show that while these vortex pins greatly reduce thermally activated current decay in the highly anisotropic material Bi-2212, significant temperature-independent current decay remains, due to quantum tunneling of vortices. An analysis of the thermally-induced current decay in a "Maley" framework provides the effective pinning energy U(J, T) of irradiated materials, for comparison with the virgin superconductors. The influence of quantum decay on this analysis is shown. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Thompson, JR (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 24 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0075-8450 BN 3-540-67188-9 J9 LECT NOTES PHYS PY 2000 VL 545 BP 181 EP 192 PG 12 WC Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BS64V UT WOS:000170703100011 ER PT J AU Fang, XG Scott, BL John, KD Kubas, GJ Watkin, JG AF Fang, XG Scott, BL John, KD Kubas, GJ Watkin, JG TI Triphenylmethyl tris(p-methoxyphenyl)phosphonium cation: a structurally characterized phosphonium analog of hexaphenylethane SO NEW JOURNAL OF CHEMISTRY LA English DT Article ID BOND AB Reaction of tris(p-methoxyphenyl)phosphine with [Ph3C][B(Ar-F)(4)] [Ar-F=3,5-(CF3)(2)C6H3] afforded [Ph3CP (4-OMeC6H4)(3)][B(Ar-F)(4)], a structural analog of hexaphenylethane, which shows a very long P-C distance [1.931(3) Angstrom] in the solid state, indicating a strong steric repulsive interaction between the two parts of the phosphonium cation. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Kubas, GJ (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, MS J514, Los Alamos, NM 87545 USA. RI Scott, Brian/D-8995-2017; OI Scott, Brian/0000-0003-0468-5396; John, Kevin/0000-0002-6181-9330 NR 20 TC 8 Z9 8 U1 0 U2 1 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1144-0546 J9 NEW J CHEM JI New J. Chem. PY 2000 VL 24 IS 10 BP 831 EP 833 DI 10.1039/b003233f PG 3 WC Chemistry, Multidisciplinary SC Chemistry GA 357PL UT WOS:000089510000019 ER PT S AU Rodriguez, MA Ingersoll, D Doughty, DH AF Rodriguez, MA Ingersoll, D Doughty, DH BE Doughty, DH Nazar, LF Arakawa, M Brack, HP Naoi, K TI In-situ X-Ray Diffraction studies on lithium-ion battery cathodes SO NEW MATERIALS FOR BATTERIES AND FUEL CELLS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on New Materials for Batteries and Fuel Cells CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Duracell Worldwide Technologies, Lawrence Berkeley Natl Lab, Nippon Telegraph & Tel Corp, Paul Scherrer Inst, Sandia Natl Labs, Sulzer Innotec, Tokyo Univ Agr & Technol, US DOE, Univ Waterloo AB LiNi0.8Co0.2O2 and LiNiO2 have been characterized in-situ XRD. LiNi0.8Co0.2O2 does not undergo a monoclinic phase transformation but remains a hexagonal lattice throughout the entire charging cycle. It is hypothesized that Co-doping may help stabilize the hexagonal structure. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Rodriguez, MA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 1 Z9 1 U1 1 U2 5 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-482-3 J9 MATER RES SOC SYMP P PY 2000 VL 575 BP 65 EP 70 PG 6 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA BQ34N UT WOS:000088058800008 ER PT S AU Bahn, CS McGraw, JM Perkins, JD Parilla, PA Ginley, DS AF Bahn, CS McGraw, JM Perkins, JD Parilla, PA Ginley, DS BE Doughty, DH Nazar, LF Arakawa, M Brack, HP Naoi, K TI Lithium ion diffusion measurements in high quality LiCoO2 thin film battery cathodes SO NEW MATERIALS FOR BATTERIES AND FUEL CELLS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on New Materials for Batteries and Fuel Cells CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Duracell Worldwide Technologies, Lawrence Berkeley Natl Lab, Nippon Telegraph & Tel Corp, Paul Scherrer Inst, Sandia Natl Labs, Sulzer Innotec, Tokyo Univ Agr & Technol, US DOE, Univ Waterloo AB Highly crystalline, textured thin films of LiCoxAl1-xO2 (x=0, 0.5) have been grown by pulsed laser deposition. Films of both stoichiometries were dense and uniaxially textured with Li, Co (or Co,AI) layers parallel to the substrate. It was found that crystal quality depended strongly on oxygen partial pressure, substrate temperature, and substrate material. The deposition of LiCo0.5Al0.5O2 is also highly dependent upon laser fluence, requiring at least 12.8 J/cm(2) for high quality films. Chemical diffusion measurements were performed over a wide range of lithium contents using the potentiostatic intermittent titration technique. Maximum and minimum effective (D) over tilde for LiCoO2 were 4.0 x 10(.11) and 1.2 x 10(.12) cm(2)/s, respectively, and for LiCo0.5Al0.5O2, 2.2 x 10(.12) and 8.0 x 10(.17) cm(2)/s, respectively. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Bahn, CS (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 10 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 1-55899-482-3 J9 MATER RES SOC SYMP P PY 2000 VL 575 BP 71 EP 76 PG 6 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA BQ34N UT WOS:000088058800009 ER PT S AU McGraw, JM Bahn, CS Parilla, PA Perkins, JD Readey, DW Ginley, DS AF McGraw, JM Bahn, CS Parilla, PA Perkins, JD Readey, DW Ginley, DS BE Doughty, DH Nazar, LF Arakawa, M Brack, HP Naoi, K TI Li ion diffusion measurements in crystalline and amorphous V2O5 thin-film battery cathodes SO NEW MATERIALS FOR BATTERIES AND FUEL CELLS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on New Materials for Batteries and Fuel Cells CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Duracell Worldwide Technologies, Lawrence Berkeley Natl Lab, Nippon Telegraph & Tel Corp, Paul Scherrer Inst, Sandia Natl Labs, Sulzer Innotec, Tokyo Univ Agr & Technol, US DOE, Univ Waterloo ID ELECTROCHEMICAL LITHIUM INTERCALATION AB Thin films of crystalline and amorphous V2O5 were deposited by pulsed laser deposition (PLD) and the chemical diffusion coefficients, (D) over tilde, were measured by the potentiostatic intermittent titration technique (PITT). In crystalline V2O5 films, the maximum and minimum (D) over tilde, were found to be 1.7 x 10(.12) cm(2)/s and 5.8 x 10(.15) cm(2)/s respectively, with a general trend for (D) over tilde to rise in single-phase regions. The changes in (D) over tilde correlated well to the known phases in LixV2O5. In amorphous V2O5 films, (D) over tilde exhibited a smooth, continuous decrease as the Li concentration increased. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP McGraw, JM (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 12 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 1-55899-482-3 J9 MATER RES SOC SYMP P PY 2000 VL 575 BP 103 EP 108 PG 6 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA BQ34N UT WOS:000088058800014 ER PT S AU Roth, EP Nagasubramanian, G AF Roth, EP Nagasubramanian, G BE Doughty, DH Nazar, LF Arakawa, M Brack, HP Naoi, K TI Degradation reactions in SONY-type Li-ion batteries SO NEW MATERIALS FOR BATTERIES AND FUEL CELLS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on New Materials for Batteries and Fuel Cells CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Duracell Worldwide Technologies, Lawrence Berkeley Natl Lab, Nippon Telegraph & Tel Corp, Paul Scherrer Inst, Sandia Natl Labs, Sulzer Innotec, Tokyo Univ Agr & Technol, US DOE, Univ Waterloo ID DIFFERENTIAL SCANNING CALORIMETRY; LITHIUM; INTERCALATION; ANODES; CELLS AB Thermal instabilities were identified in SONY-type lithium-ion cells and correlated with interactions of cell constituents and reaction products. Three temperature regions of interaction were identified and associated with the state of charge (degree of Li intercalation) of the cell. Anodes were shown to undergo exothermic reactions as low as 100 degrees C involving the solid electrolyte interface (SEI) layer and the LiPF6 salt in the electrolyte (EC:PC:DEC/LiPF6). These reactions could account for the thermal runaway observed in these cells beginning at 100 degrees C. Exothermic reactions were also observed in the 200 degrees C-300 degrees C region between the intercalated lithium anodes, the LiPF6 salt, and the PVDF. These reactions were followed by a high-temperature reaction region, 300 degrees C-400 degrees C, also involving the PVDF binder and the intercalated lithium anodes. The solvent was not directly involved in these reactions but served as a moderator and transport medium. Cathode exothermic reactions with the PVDF binder were observed above 200 degrees C and increased with the state of charge (decreasing Li content). This offers an explanation for the observed lower thermal runaway temperatures for charged cells. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Roth, EP (reprint author), Sandia Natl Labs, POB 5800 MSo613, Albuquerque, NM 87185 USA. NR 8 TC 0 Z9 0 U1 0 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-482-3 J9 MATER RES SOC SYMP P PY 2000 VL 575 BP 143 EP 148 PG 6 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA BQ34N UT WOS:000088058800020 ER PT S AU Guidotti, RA Even, WR AF Guidotti, RA Even, WR BE Doughty, DH Nazar, LF Arakawa, M Brack, HP Naoi, K TI Effect on performance of composition of Li-ion carbon anodes derived from PMAN/DVB copolymers SO NEW MATERIALS FOR BATTERIES AND FUEL CELLS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on New Materials for Batteries and Fuel Cells CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Duracell Worldwide Technologies, Lawrence Berkeley Natl Lab, Nippon Telegraph & Tel Corp, Paul Scherrer Inst, Sandia Natl Labs, Sulzer Innotec, Tokyo Univ Agr & Technol, US DOE, Univ Waterloo ID LITHIUM INSERTION AB The effects on electrochemical performance of the nitrogen content of disordered carbons derived from polymethacryonitrile (PMAN)-divinylbenzene (DVB) copolymers were examined in galvanostatic cycling tests between 2 V and 0.01 V vs, Li/Li+ in 1M LiPF6/ethylene carbonate (EC)-dimethyl carbonate (DMC). The first-cycle reversible capacities and coulombic efficiencies increased with increase in the level of nitrogen for samples prepared at 700 degrees C. However, the degree of fade also increased. Similar tests were performed on materials that were additionally heated at 1,000 degrees and 1,300 degrees C for five hours. Loss of nitrogen, oxygen, and hydrogen occurred under these conditions, with none remaining at the highest temperature in all cases but one. The pyrolysis temperature dominated the electrochemical performance for these samples, with lower reversible and irreversible capacities for the first intercalation cycle as the pyrolysis temperature was increased. Fade was reduced and coulombic efficiencies also improved with increase in temperate. The large irreversible capacities and high fade of these materials makes them unsuitable for use in Li-ion cells. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Guidotti, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 9 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 1-55899-482-3 J9 MATER RES SOC SYMP P PY 2000 VL 575 BP 165 EP 171 PG 7 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA BQ34N UT WOS:000088058800022 ER PT S AU Busick, D Wilson, M AF Busick, D Wilson, M BE Doughty, DH Nazar, LF Arakawa, M Brack, HP Naoi, K TI Development of composite materials for PEFC bipolar plates SO NEW MATERIALS FOR BATTERIES AND FUEL CELLS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on New Materials for Batteries and Fuel Cells CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Duracell Worldwide Technologies, Lawrence Berkeley Natl Lab, Nippon Telegraph & Tel Corp, Paul Scherrer Inst, Sandia Natl Labs, Sulzer Innotec, Tokyo Univ Agr & Technol, US DOE, Univ Waterloo AB The most costly and problematic components of fuel cell stacks may be bipolar plates. Besides meeting cost constraints, bipolar plates must possess a host of other properties including low gas permeability, corrosion resistance, low weight, high strength, and manufacturability. While we have developed a baseline composite material that meets these requirements, further optimization and development have resulted in significant improvements in properties and processability. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Busick, D (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 3 TC 17 Z9 18 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-482-3 J9 MATER RES SOC SYMP P PY 2000 VL 575 BP 247 EP 251 PG 5 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA BQ34N UT WOS:000088058800031 ER PT S AU Wilkenhoener, R Buchkremer, HP Stoever, D Stolten, D Koch, A AF Wilkenhoener, R Buchkremer, HP Stoever, D Stolten, D Koch, A BE Doughty, DH Nazar, LF Arakawa, M Brack, HP Naoi, K TI Heat-resistant, electrically conducting joint between ceramic end plates and metallic conductors in solid oxide fuel cell SO NEW MATERIALS FOR BATTERIES AND FUEL CELLS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on New Materials for Batteries and Fuel Cells CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Duracell Worldwide Technologies, Lawrence Berkeley Natl Lab, Nippon Telegraph & Tel Corp, Paul Scherrer Inst, Sandia Natl Labs, Sulzer Innotec, Tokyo Univ Agr & Technol, US DOE, Univ Waterloo AB Ceramic parts made of doped lanthanum chromite are used as interconnects and end plates in stacks for several solid oxide fuel cell (SOFC) designs. Metallic conductors have to be attached to enable a low-resistance connection between individual stacks in each SOFC unit and to permit power to be drawn from the SOFC. The resistances of the metal-ceramic bond and the metallic conductors have to be stable under operating conditions, i.e., 1000 degrees C in air. Consequently, heat-resistant materials have to be used. A two-step process has been developed to connect commercially available, Ni- or Fe-based metallic conductors to ceramic SOFC end plates by vacuum furnace brazing. In the first step, a metallic sheet, which acts as the current collector, is brazed onto the ceramic end plate. Thereby, the much lower electrical conductivity of the ceramic part is compensated by that of the metal. The chromium alloy CrFe5Y(2)I(3)1 is suitable because it is heat-resistant, and its thermal expansion coefficient is close to that of lanthanum chromite. In the second step, metallic wires or strips are brazed on the current collector. Since this joint area is significantly smaller than that of the first joint, materials with a different thermal expansion coefficient can be used, such as conventional heat-resistant nickel alloys (Inconel 617) and ferritic stainless steels (FeCrAl 25 5). Filler alloys for both brazing steps with matching melting points have been found. Hence, both brazing steps can be performed cost-effectively in one heating step. Suitable parameters for vacuum furnace brazing of both joints are presented, and the composition of the filler alloys is given. Data concerning the long-term behavior of the joint resistances in air at 1000 degrees C are discussed. C1 Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, Argonne, IL 60439 USA. RP Wilkenhoener, R (reprint author), Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 4 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 1-55899-482-3 J9 MATER RES SOC SYMP P PY 2000 VL 575 BP 295 EP 302 PG 8 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA BQ34N UT WOS:000088058800036 ER PT S AU Ralph, JM Kilner, JA Steele, BCH AF Ralph, JM Kilner, JA Steele, BCH BE Doughty, DH Nazar, LF Arakawa, M Brack, HP Naoi, K TI Improving Gd-doped ceria electrolytes for low temperature solid oxide fuel cells SO NEW MATERIALS FOR BATTERIES AND FUEL CELLS SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on New Materials for Batteries and Fuel Cells CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Duracell Worldwide Technologies, Lawrence Berkeley Natl Lab, Nippon Telegraph & Tel Corp, Paul Scherrer Inst, Sandia Natl Labs, Sulzer Innotec, Tokyo Univ Agr & Technol, US DOE, Univ Waterloo AB Gadolinia-doped ceria electrolyte is being investigated as an alternative electrolyte for solid oxide fuel cells operating at temperatures below 700 degrees C. Measurements were made to determine the effects that small additions of Ca, Pr and Fe to gadolinia-doped ceria have on the bulk and grain boundary conductivities. These small additions (1-2%) of dopant did not alter the bulk conductivity significantly but resulted in a large increase in the grain boundary conductivity. The grain boundary conductivity was similar for all three electrolyte compositions. These results are explained by the possible formation of second phases at the grain boundary, which can incorporate impurity elements. The electronic conductivity in these electrolyte materials was also evaluated, but it was found that the Ca, Pr and Fe additions do not reduce the electronic conductivity compared to a standard Gd-doped ceria sample. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Ralph, JM (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. EM ralph@cmt.anl.gov NR 12 TC 1 Z9 2 U1 1 U2 9 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-482-3 J9 MATER RES SOC SYMP P PY 2000 VL 575 BP 309 EP 314 PG 6 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA BQ34N UT WOS:000088058800038 ER PT S AU Morse, JD Graff, RT Hayes, JP Jankowski, AF AF Morse, JD Graff, RT Hayes, JP Jankowski, AF BE Doughty, DH Nazar, LF Arakawa, M Brack, HP Naoi, K TI Porous thin-film anode materials for solid-oxide fuel cells SO NEW MATERIALS FOR BATTERIES AND FUEL CELLS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on New Materials for Batteries and Fuel Cells CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Duracell Worldwide Technologies, Lawrence Berkeley Natl Lab, Nippon Telegraph & Tel Corp, Paul Scherrer Inst, Sandia Natl Labs, Sulzer Innotec, Tokyo Univ Agr & Technol, US DOE, Univ Waterloo ID YTTRIA-STABILIZED ZIRCONIA; SPUTTER-DEPOSITION; LOW-TEMPERATURE; ELECTROLYTES AB Thin film, solid-oxide fuel cells (TFSOFCs) synthesized from an electrolyte and conductive material are developed using photolithographic patterning and physical vapor deposition. The anode layer must enable combination of the reactive gases, be conductive to pass the electric current, and provide mechanical support to the electrolyte and cathode layers. The microstructure and morphology desired for the anode layer should facilitate generation of maximum current density from the fuel cell. For these purposes, the parameters of the deposition process and post-deposition patterning are developed to optimize a continuous porosity across the anode layer. The anode microstructure is characterized using scanning electron microscopy and the power ouput generated through current-voltage measurement. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Morse, JD (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 12 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 1-55899-482-3 J9 MATER RES SOC SYMP P PY 2000 VL 575 BP 321 EP 324 PG 4 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA BQ34N UT WOS:000088058800040 ER PT S AU Wright, RB Murphy, TC Jamison, DK Rogers, SA AF Wright, RB Murphy, TC Jamison, DK Rogers, SA BE Doughty, DH Nazar, LF Arakawa, M Brack, HP Naoi, K TI Recent DOE sponsored electrochemical capacitor test results SO NEW MATERIALS FOR BATTERIES AND FUEL CELLS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on New Materials for Batteries and Fuel Cells CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Duracell Worldwide Technologies, Lawrence Berkeley Natl Lab, Nippon Telegraph & Tel Corp, Paul Scherrer Inst, Sandia Natl Labs, Sulzer Innotec, Tokyo Univ Agr & Technol, US DOE, Univ Waterloo AB Electrochemical capacitors (ultracapacitors) are being developed for hybrid vehicles as candidate power assist devices for the fast response engine and for other energy storage systems that can utilize the high power densities available from these devices. Ultracapacitors show promise toward being able to accept high regenerative pulses and high power delivery capabilities while exhibiting very high cycle life. This paper will present recent test data from two U.S. Department of Energy (DOE) supported ultracapacitor projects designed to meet the fast response engine requirements. Constant-current and constant-power test results will be presented that have been acquired from recent prototype capacitors supplied by SAFT America, Inc. (ten devices), and Maxwell Energy Products, Inc. (two devices). The SAFT capacitors are rated at 0.5 V to 3 V with capacitance ratings ranging from 135 F to 138 F. Capacitor cells rated at 2.3 V and 101.4 F were also evaluated that were produced by Maxwell Energy Products, Inc. Both sets of devices used proprietary carbon electrodes with non-aqueous electrolytes in their design. From the constant-current discharge tests, the discharge current dependence of the capacitance, equivalent series resistance, and PC-time constant were determined as well as the capacitors' voltage dependence of the capacitance. Constant-power discharge tests permitted the specific energy as a function of the specific power to be determined, and also the discharge/charge round trip efficiency as a function of the magnitude of the constant-power discharge. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Wright, RB (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 6 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 1-55899-482-3 J9 MATER RES SOC SYMP P PY 2000 VL 575 BP 381 EP 394 PG 14 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA BQ34N UT WOS:000088058800048 ER PT S AU Mani, SS Fleming, JG Sniegowski, JJ De Boer, MP Irwin, LW Walraven, JA Tanner, DM Dugger, MT AF Mani, SS Fleming, JG Sniegowski, JJ De Boer, MP Irwin, LW Walraven, JA Tanner, DM Dugger, MT BE Wadley, HNG Gilmer, GH Barker, WG TI Chemical vapor deposition coating for micromachines SO NEW METHODS, MECHANISMS AND MODELS OF VAPOR DEPOSITION SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on New Methods, Mechanisms and Models of Vapor Deposition CY APR 24-26, 2000 CL SAN FRANCISCO, CA SP Mat Res Soc ID TUNGSTEN AB Two major problems associated with Si-based MEMS devices are stiction and wear. Surface modifications are needed to reduce both adhesion and friction in micromechanical structures to solve these problems. In this paper, we will present a process used to selectively coat MEMS devices with tungsten using a CVD (Chemical Vapor Deposition) process. The selective W deposition process results in a very conformal coating and can potentially solve both stiction and wear problems confronting MEMS processing. The selective deposition of tungsten is accomplished through silicon reduction of WF6, which results in a self-limiting reaction. The selective deposition of W only on polysilicon surfaces prevents electrical shorts. Further, the self-limiting nature of this selective W deposition process ensures the consistency necessary for process control. Selective tungsten is deposited after the removal of the sacrificial oxides to minimize process integration problems. This tungsten coating adheres well and is hard and conducting, requirements for device performance. Furthermore, since the deposited tungsten infiltrates under adhered silicon parts and the volume of W deposited is less than the amount of Si consumed, it appears to be possible to release stuck parts that are contacted over small areas such as dimples. Results from tungsten deposition on MEMS structures with dimples will be presented. The effect of wet and vapor phase cleans prior to the deposition will be discussed along with other process details. The W coating improved wear by orders of magnitude compared to uncoated parts. 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 20 TC 5 Z9 5 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-524-2 J9 MATER RES SOC SYMP P PY 2000 VL 616 BP 21 EP 26 PG 4 WC Materials Science, Coatings & Films SC Materials Science GA BR97L UT WOS:000168247100004 ER PT S AU Adams, DP Romero, JA Rodriguez, MA Floro, JA Banks, JC AF Adams, DP Romero, JA Rodriguez, MA Floro, JA Banks, JC BE Wadley, HNG Gilmer, GH Barker, WG TI Composition and structure of sputter deposited erbium hydride thin films SO NEW METHODS, MECHANISMS AND MODELS OF VAPOR DEPOSITION SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on New Methods, Mechanisms and Models of Vapor Deposition CY APR 24-26, 2000 CL SAN FRANCISCO, CA SP Mat Res Soc ID SWITCHABLE OPTICAL-PROPERTIES; NB(110) FILMS; HYDROGEN; YTTRIUM AB Erbium hydride thin films are grown onto polished, a-axis alpha Al2O3 (sapphire) substrates by reactive ion beam sputtering and analyzed to determine composition, phase and microstructure. Erbium is sputtered while maintaining a Hz partial pressure of 1.4 x10(-4) Torr. Growth is conducted at several substrate temperatures between 30 and 500 degreesC. Rutherford backscattering spectrometry (RBS) and elastic recoil detection analyses after deposition show that the H/Er areal density ratio is approximately 3:1 for growth temperatures of 30, 150 and 275 degreesC, while for growth above similar to 430 degreesC, the ratio of hydrogen to metal is closer to 2:1. However, x-ray diffraction shows that all films have a cubic metal sublattice structure corresponding to that of ErH2. RES and Auger electron spectroscopy confirm that sputtered erbium hydride thin films are relatively free of impurities. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Adams, DP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 2 Z9 2 U1 1 U2 5 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-524-2 J9 MATER RES SOC SYMP P PY 2000 VL 616 BP 87 EP 92 PG 4 WC Materials Science, Coatings & Films SC Materials Science GA BR97L UT WOS:000168247100014 ER PT J AU Miller, SP AF Miller, SP TI Arbuscular mycorrhizal colonization of semi-aquatic grasses along a wide hydrologic gradient SO NEW PHYTOLOGIST LA English DT Article DE arbuscular mycorrhizal fungi; flooding; gradient; inoculum potential; Leersia hexandra; Panicum hemitomon; wetlands ID SOIL DISTURBANCE; VASCULAR PLANTS; FUNGI; WETLAND; DYNAMICS; GROWTH; ROOTS; INFECTIVITY; VEGETATION; MORPHOLOGY AB The effect of soil flooding on arbuscular-mycorrhizal (AM) fungal colonization of wetland plants was investigated using Panicum hemitomon and Leersia hexandra, two semi-aquatic grasses (Graminaceae) that grow along a wide hydrologic gradient in Carolina bay wetlands of the southeastern US coastal plain. Three related investigations were conducted along the dry-to-wet gradient in these wetlands; a field survey of AM fungal root colonization in eight wetlands, monthly monitoring of colonization patterns in P. hemitomon over a growing season, and an inoculum potential bioassay of soils collected along the gradient. The field survey showed that AM fungal colonization was strongly negatively correlated with water depth, but colonization was present in most root samples. The monthly assessment indicated that AM fungal colonization was lowest in plots that were consistently wet but rose as some plots underwent seasonal drying. The inoculum potential assay of dry, intermediate, and wet soils performed under both dry and saturated conditions showed that soils that were wet for >1 yr had the same ability to form mycorrhizas in bait plants as those that had remained dry. These findings suggested that the lower degree of colonization in wet areas observed in the field survey was because of the presence of surface water rather than low numbers of mycorrhizal propagules in the soil. Overall, the results of these investigations show that flooding is partially but not totally inhibitory to AM fungal colonization of wetland grasses. C1 Univ Georgia, Inst Ecol, Athens, GA 30605 USA. Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Miller, SP (reprint author), W Virginia Univ, Dept Biol, POB 6057, Morgantown, WV 26506 USA. NR 50 TC 70 Z9 80 U1 2 U2 23 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0028-646X J9 NEW PHYTOL JI New Phytol. PD JAN PY 2000 VL 145 IS 1 BP 145 EP 155 DI 10.1046/j.1469-8137.2000.00566.x PG 11 WC Plant Sciences SC Plant Sciences GA 280RW UT WOS:000085116800016 ER PT S AU Klasen, M AF Klasen, M BE Grindhammer, G Kniehl, BA Kramer, G TI Photos structure and the production of jets, hadrons, and prompt photons SO NEW TRENDS IN HERA PHYSICS 1999 SE LECTURE NOTES IN PHYSICS LA English DT Proceedings Paper CT International Workshop on New Trends in HERA Physics 1999 CY MAY 30-JUN 04, 1999 CL RINGBERG CASTLE, GERMANY ID TO-LEADING ORDER; PARTON DISTRIBUTIONS; CROSS-SECTIONS; HERA; PHOTOPRODUCTION; COLLISIONS; QCD; EP AB We give a pedagogical introduction to hard photoproduction processes at HERA, including the production of jets, hadrons, and prompt photons. Recent theoretical developments in the three areas are reviewed. C1 Argonne Natl Lab, HEP Theory Grp, Argonne, IL 60439 USA. RP Klasen, M (reprint author), Argonne Natl Lab, HEP Theory Grp, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 28 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0075-8450 BN 3-540-67156-0 J9 LECT NOTES PHYS PY 2000 VL 546 BP 250 EP 261 PG 12 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BQ50R UT WOS:000088541300019 ER PT S AU Harris, B AF Harris, B BE Grindhammer, G Kniehl, BA Kramer, G TI Open charm production in deep inelastic scattering at next-to-leading order at HERA SO NEW TRENDS IN HERA PHYSICS 1999 SE LECTURE NOTES IN PHYSICS LA English DT Proceedings Paper CT International Workshop on New Trends in HERA Physics 1999 CY MAY 30-JUN 04, 1999 CL RINGBERG CASTLE, GERMANY ID HEAVY FLAVOR PRODUCTION; CROSS-SECTIONS; O(ALPHA-S) CORRECTIONS; ELECTROPRODUCTION; QUARK; DISTRIBUTIONS; RESUMMATION; NLO; QCD AB An introduction and overview of charm production in deep inelastic scattering at HERA is given. The existing next-to-leading order perturbative QCD calculations are then reviewed, and key results are summarized. Finally, comparisons are made with the most recent HERA data, and unresolved issues are highlighted. C1 Argonne Natl Lab, HEP Theory Grp, Argonne, IL 60439 USA. RP Harris, B (reprint author), Argonne Natl Lab, HEP Theory Grp, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 38 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0075-8450 BN 3-540-67156-0 J9 LECT NOTES PHYS PY 2000 VL 546 BP 290 EP 302 PG 13 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BQ50R UT WOS:000088541300022 ER PT S AU Goldhaber, M AF Goldhaber, M BE Diwan, MV Jung, CK TI Opening remarks at the Next Generation Nucleon Decay and Neutrino Detector Workshop (NNN99) - State University of New York at Stonybrook, Sep. 23-25, 1999 SO NEXT GENERATION NUCLEON DECAY AND NEUTRINO DETECTOR SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Next Generation Nucleon Decay and Neutrino Detector CY SEP 23-25, 1999 CL STONY BROOK, NY SP SUNY, Stony Brook, Brookhaven Natl Lab, Hamamatsu Corp AB In this workshop we are trying to look ahead at what new detectors can do to improve answers to questions concerning proton decay and the masses and mixing of neutrinos. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Goldhaber, M (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 0 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 1-56396-956-4 J9 AIP CONF PROC PY 2000 VL 533 BP 3 EP 5 PG 3 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BQ78Y UT WOS:000089525900001 ER PT S AU Mocioiu, I Shrock, R AF Mocioiu, I Shrock, R BE Diwan, MV Jung, CK TI Matter effects on long baseline neutrino oscillation experiments SO NEXT GENERATION NUCLEON DECAY AND NEUTRINO DETECTOR SE AIP Conference Proceedings LA English DT Proceedings Paper CT Workshop on Next Generation Nucleon Decay and Neutrino Detector CY SEP 23-25, 1999 CL STONY BROOK, NY SP SUNY, Stony Brook, Brookhaven Natl Lab, Hamamatsu Corp ID ATMOSPHERIC NEUTRINOS; SUPER-KAMIOKANDE; PARAMETRIC RESONANCE; ENERGY-SPECTRUM; LSND EXPERIMENT; SOLAR; PHYSICS; EARTH; REGENERATION; FLUX AB We calculate matter effects on neutrino oscillations relevant for long baseline neutrino oscillation experiments. In particular, we compare the results obtained with simplifying approximations for the density profile in the Earth versus results obtained with actual density profiles. We study the dependence of the oscillation signals on both E/Delta m(atm)(2), and on the angles in the leptonic mixing matrix. The results show quantitatively how matter effects can cause significant changes in the oscillation signals, relative to vacuum oscillations and can be useful in amplifying these signals and helping one to obtain measurements of mixing parameters and the magnitude and sign of Delta m(2). C1 SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. NR 38 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 1-56396-956-4 J9 AIP CONF PROC PY 2000 VL 533 BP 74 EP 79 PG 2 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BQ78Y UT WOS:000089525900011 ER PT S AU Barr, SM Albright, CH AF Barr, SM Albright, CH BE Diwan, MV Jung, CK TI SO(10) and large v(mu)-v(tau) mixing SO NEXT GENERATION NUCLEON DECAY AND NEUTRINO DETECTOR SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Next Generation Nucleon Decay and Neutrino Detector CY SEP 23-25, 1999 CL STONY BROOK, NY SP SUNY, Stony Brook, Brookhaven Natl Lab, Hamamatsu Corp ID UNIFICATION; MASSES; QUARK AB A general approach to understanding the Large mixing seen in atmospheric neutrinos is explained, as well as a highly predictive SO(10) model which implements this approach. It is also seen how bimaximal mixing naturally arises in this scheme. C1 Univ Delaware, Bartol Res Inst, Newark, DE 19716 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Barr, SM (reprint author), Univ Delaware, Bartol Res Inst, Newark, DE 19716 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 1-56396-956-4 J9 AIP CONF PROC PY 2000 VL 533 BP 80 EP 83 PG 2 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BQ78Y UT WOS:000089525900012 ER PT S AU Parsa, Z AF Parsa, Z BE Diwan, MV Jung, CK TI Moon storage rings - Neutrino factories SO NEXT GENERATION NUCLEON DECAY AND NEUTRINO DETECTOR SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Next Generation Nucleon Decay and Neutrino Detector CY SEP 23-25, 1999 CL STONY BROOK, NY SP SUNY, Stony Brook, Brookhaven Natl Lab, Hamamatsu Corp ID OSCILLATION EXPERIMENTS; CP VIOLATION; MUON COLLIDER; SOLAR; MATTER; SPECTRUM; MAJORANA; PHYSICS AB The concept of a muon storage ring based-Neutrino Source (Neutrino Factory) has sparked considerable interest in the High Energy Physics community. Besides providing a first phase of a muon collider facility, it would generate more intense and well collimated neutrino beams than currently available. The BNL-AGS or some other proton driver would provide an intense proton beam that hits a target, produces pions that decay into muons. The muons must be cooled, accelerated and injected into a storage ring with a long straight section where they decay. The decays occurring in the straight sections of the ring would generate neutrino beams that could be directed to detectors located thousands of kilometers away, allowing studies of neutrino oscillations with precisions not currently accessible. For example, with the neutrino source at BNL, detectors at Soudan, Minnesota (1715 km), and Gran Sasso, Italy (6527 km) become-very interesting possibilities. The feasibility of constructing and operating such a muon-storage-ring based Neutrino-Factory, including geotechnical questions related to building non-planar storage rings (e.g. at 8 degrees angle for BNL-Soudan, and 31 degrees angle for BNL-Gran Sasso) along with the design of the muon capture, cooling, acceleration, and storage ring for such a facility is being explored by our growing Neutrino Factory and Muon Collider Collaboration (NFMCC). We present overview of Neutrino Factory concept based on a muon storage ring, its components, physics opportunities, Possible upgrade to a full muon collider, latest simulations of front-end, and a new bowtie - muon storage ring design. C1 Brookhaven Natl Lab, Phys Dept 510A, Upton, NY 11973 USA. RP Parsa, Z (reprint author), Brookhaven Natl Lab, Phys Dept 510A, Upton, NY 11973 USA. NR 75 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 1-56396-956-4 J9 AIP CONF PROC PY 2000 VL 533 BP 181 EP 195 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BQ78Y UT WOS:000089525900029 ER PT S AU Tayloe, R AF Tayloe, R CA BooNE Collaboration BE Diwan, MV Jung, CK TI The Booster Neutrino Experiment: BooNE SO NEXT GENERATION NUCLEON DECAY AND NEUTRINO DETECTOR SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Next Generation Nucleon Decay and Neutrino Detector CY SEP 23-25, 1999 CL STONY BROOK, NY SP SUNY, Stony Brook, Brookhaven Natl Lab, Hamamatsu Corp ID (NU)OVER-BAR(MU)->(NU)OVER-BAR(E) OSCILLATIONS; LSND EXPERIMENT; DECAY AB The Booster Neutrino Experiment (BooNE) has been approved to run at Fermilab and is currently under construction. This experiment will definitively test the result from LSND that indicates neutrino oscillations. If the LSND result is due to nu(mu) --> nu(e) oscillations, the first stage of the experiment (miniBooNE) will observe approximately 1000 oscillation events in the first calendar year of operation. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Tayloe, R (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 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 1-56396-956-4 J9 AIP CONF PROC PY 2000 VL 533 BP 205 EP 210 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BQ78Y UT WOS:000089525900031 ER PT S AU Harris, DA AF Harris, DA BE Diwan, MV Jung, CK TI Summary of detector and beam parameters working group from Lyon SO NEXT GENERATION NUCLEON DECAY AND NEUTRINO DETECTOR SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Next Generation Nucleon Decay and Neutrino Detector CY SEP 23-25, 1999 CL STONY BROOK, NY SP SUNY, Stony Brook, Brookhaven Natl Lab, Hamamatsu Corp AB This report is an overview of the discussions and talks that occurred during the detectors and beams working group of the NuFact99 workshop in Lyon, France. A wish list of muon beam parameters is given, as well as a survey of currently studied oscillation detector technologies. Finally, a short description of the non-oscillation physics that would be accessible is included to show how the diversity of neutrino physics a muon storage ring could address. Workshop talk slides can be found in ht tp: //muonstoragerings.cern.ch/Welcome.html/ C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Harris, DA (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 7 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 1-56396-956-4 J9 AIP CONF PROC PY 2000 VL 533 BP 240 EP 243 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BQ78Y UT WOS:000089525900035 ER PT S AU Bernstein, R AF Bernstein, R BE Diwan, MV Jung, CK TI Summary of accelerator neutrino experiments working group SO NEXT GENERATION NUCLEON DECAY AND NEUTRINO DETECTOR SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Next Generation Nucleon Decay and Neutrino Detector CY SEP 23-25, 1999 CL STONY BROOK, NY SP SUNY, Stony Brook, Brookhaven Natl Lab, Hamamatsu Corp AB Our group focused on searches for neutrino oscillations at a muon storage ring. In the experimental realm, we heard a report from J. Wilkes on the first K2K event. S. Boyd discussed distinguishing nu(mu) -->nu(tau) from nu(mu) --> nu(s) in SuperK using the up/down neutral current ratio. Progress in theoretical work was given by M. Campanelli, discussing matter-enhancement effects in the context of ICANOE. I. Mocioiu presented oscillation probabilities for matter-enhancement over long-baselines vs. LIE. Finally, we examined physics goals for a neutrino oscillation experiment at a muon storage ring long-baseline experiment. In that context, Deborah Harris summarized the discussions at the Lyon Workshop. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Bernstein, R (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 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 1-56396-956-4 J9 AIP CONF PROC PY 2000 VL 533 BP 244 EP 245 PG 2 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BQ78Y UT WOS:000089525900036 ER PT B AU Wurtz, R Cook, KH Bennett, CL Bixler, J Carr, D Wishnow, EH AF Wurtz, R Cook, KH Bennett, CL Bixler, J Carr, D Wishnow, EH BE Smith, EP Long, KS TI Ground-based demonstration of imaging Fourier transform spectrometry and techniques SO NGST SCIENCE AND TECHNOLOGY EXPOSITION SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT NGST Science and Technology Exposition Conference CY SEP 13-16, 1999 CL HYANNIS, MA AB We present results from a four-port Michelson interferometer built to demonstrate imaging Fourier transform spectroscopy for astronomical applications. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wurtz, R (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 7 TC 6 Z9 6 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-036-6 J9 ASTR SOC P PY 2000 VL 207 BP 203 EP 211 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ80R UT WOS:000089621100021 ER PT B AU Bennett, CL AF Bennett, CL BE Smith, EP Long, KS TI A comparison of imaging spectrometers SO NGST SCIENCE AND TECHNOLOGY EXPOSITION SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT NGST Science and Technology Exposition Conference CY SEP 13-16, 1999 CL HYANNIS, MA ID DEEP FIELD AB Realistic signal to noise performance estimates for the various types of instruments being considered for NGST are compared, based on the point source detection values quoted in the available ISIM final reports. The corresponding sensitivity of the various types of spectrometers operating in a full field imaging mode, for both emission line objects and broad spectral distribution objects, is computed and displayed. For the purpose of seeing the earliest galaxies, or the faintest possible emission fine sources, the imaging Fourier transform spectrometer emerges superior to all others, by orders of magnitude in speed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Bennett, CL (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-43, Livermore, CA 94550 USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-036-6 J9 ASTR SOC P PY 2000 VL 207 BP 344 EP 353 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ80R UT WOS:000089621100036 ER PT B AU Ge, J Ciarlo, D Kuzmenko, P Macintosh, B Alcock, C Cook, K AF Ge, J Ciarlo, D Kuzmenko, P Macintosh, B Alcock, C Cook, K BE Smith, EP Long, KS TI Etched silicon gratings for NGST SO NGST SCIENCE AND TECHNOLOGY EXPOSITION SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT NGST Science and Technology Exposition Conference CY SEP 13-16, 1999 CL HYANNIS, MA ID SPECTROSCOPY AB We have developed the world's first etched silicon grisms at LLNL in September 1999. The high optical surface quality of the grisms allows diffraction-limited spectral resolution in the IR wavelengths where silicon has good transmission. We estimated that the scattering light level is less than 4% at 2.2 mu m. Silicon can significantly increase the dispersive power of spectroscopic instruments for NGST due to its very large refractive index (n = 3.4). For example, a silicon grism with 40 mm clear entrance aperture and a 46 degrees wedge angle can provide R = 10,000-100,000 in similar to 1-10 mu m. The same grating working in the immersed reflection mode can provide similar to three times higher spectral resolution than in the transmission mode. To achieve a desired spectral resolution for NGST, the spectrograph size and weight can be significantly reduced if silicon gratings are used instead of conventional gratings. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Ge, J (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-036-6 J9 ASTR SOC P PY 2000 VL 207 BP 457 EP 461 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ80R UT WOS:000089621100053 ER PT B AU Goux, JP Kulkarni, S Linderoth, J Yoder, M AF Goux, JP Kulkarni, S Linderoth, J Yoder, M GP IEEE IEEE TI An enabling framework for master-worker applications on the computational grid SO NINTH INTERNATIONAL SYMPOSIUM ON HIGH-PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 9th IEEE International Symposium on High Performance Distributed Computing CY AUG 01-04, 2000 CL PITTSBURGH, PA SP IEEE, Comp Soc Tech Comm Distrib Proc, Univ Arizonia, Dept ECE, Carnegie Mellon Univ, Argonne Natl Lab, Pittsburgh Supercomp Ctr ID WEB AB We describe MW - a software framework that allows users to quickly and easily parallelize scientific computations using the master-worker paradigm on the computational grid. MW provides both a "top level" interface to application software and a "bottom level" interface to existing grid computing toolkits. Both interfaces are briefly described. We conclude with a case study, where the necessary Grin services are provided by the Condor high-throughput computing system, and the MW-enabled application code is used to solve a combinatorial optimization problem of unprecedented complexity. C1 Northwestern Univ, Dept Elect & Comp Engn, Div Math & Comp Sci, Argonne Natl Lab, Argonne, IL 60439 USA. RP Goux, JP (reprint author), Northwestern Univ, Dept Elect & Comp Engn, Div Math & Comp Sci, Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Linderoth, Jeffrey/B-4995-2013 OI Linderoth, Jeffrey/0000-0003-4442-3059 NR 26 TC 37 Z9 38 U1 1 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0784-0 PY 2000 BP 43 EP 50 DI 10.1109/HPDC.2000.868633 PG 8 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BQ76L UT WOS:000089454200005 ER PT B AU Tierney, B Crowley, B Gunter, D Holding, M Lee, J Thompson, M AF Tierney, B Crowley, B Gunter, D Holding, M Lee, J Thompson, M GP IEEE IEEE TI A monitoring sensor management system for grid environments SO NINTH INTERNATIONAL SYMPOSIUM ON HIGH-PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 9th IEEE International Symposium on High Performance Distributed Computing CY AUG 01-04, 2000 CL PITTSBURGH, PA SP IEEE, Comp Soc Tech Comm Distrib Proc, Univ Arizonia, Dept ECE, Carnegie Mellon Univ, Argonne Natl Lab, Pittsburgh Supercomp Ctr AB Large distributed systems such as Computational Grids require a large amount of monitoring data be collected for a variety of tasks such as fault detection, performance analysis, performance tuning, performance prediction, and scheduling. Ensuring that all necessary monitoring is turned on and that data is being collected can be a very tedious and error-prone task. We have developed an agent-based system to automate the execution of monitoring sensors and the collection of event darn. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Comp Sci Directorate, Berkeley, CA 94720 USA. RP Tierney, B (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Comp Sci Directorate, Berkeley, CA 94720 USA. NR 17 TC 8 Z9 11 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0784-0 PY 2000 BP 97 EP 104 DI 10.1109/HPDC.2000.868639 PG 8 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BQ76L UT WOS:000089454200011 ER PT B AU Beiriger, JI Bivens, HP Humphreys, SL Johnson, WR Rhea, RE AF Beiriger, JI Bivens, HP Humphreys, SL Johnson, WR Rhea, RE GP IEEE IEEE TI Constructing the ASCI computational grid SO NINTH INTERNATIONAL SYMPOSIUM ON HIGH-PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 9th IEEE International Symposium on High Performance Distributed Computing CY AUG 01-04, 2000 CL PITTSBURGH, PA SP IEEE, Comp Soc Tech Comm Distrib Proc, Univ Arizonia, Dept ECE, Carnegie Mellon Univ, Argonne Natl Lab, Pittsburgh Supercomp Ctr AB The Accelerated Strategic Computing Initiative (ASCI) computational grid is being constructed to interconnect the high performance computing resources of the nuclear weapons complex. The grid will simplify access to the diverse computing, storage, network, and visualization resources, and will enable the coordinated use of shared resources regardless of location. To match existing hardware platforms, required security services, and current simulation practices, the Globus MetaComputing Toolkit[1] was selected to provide core grid services. The ASCI grid extends Globus functionality by operating as an independent grid, incorporating Kerberos-based security, interfacing to Sandia'S Cplant(TM), and extending job monitoring services. To fully meet ASCI's needs, the architecture layers distributed work management and criteria-driven resource selection services on top of Globus. These services simplify the grid interface by allowing users to simply request "run code X anywhere" This paper describes the initial design and prototype of the ASCI grid. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Beiriger, JI (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 10 Z9 10 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0784-0 PY 2000 BP 193 EP 199 DI 10.1109/HPDC.2000.868650 PG 7 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BQ76L UT WOS:000089454200022 ER PT B AU Becla, J Hanushevsky, A AF Becla, J Hanushevsky, A GP IEEE IEEE TI Creating large scale database servers SO NINTH INTERNATIONAL SYMPOSIUM ON HIGH-PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 9th IEEE International Symposium on High Performance Distributed Computing CY AUG 01-04, 2000 CL PITTSBURGH, PA SP IEEE, Comp Soc Tech Comm Distrib Proc, Univ Arizonia, Dept ECE, Carnegie Mellon Univ, Argonne Natl Lab, Pittsburgh Supercomp Ctr AB The BaBar experiment at the Stanford Linear Accelerator Center (SLAC) is designed to perform a high precision investigation of the decays of the B-meson produced from electron-positron interactions. The experiment, started in May 1999 will generate approximately 300TB/year of data for 10 years. All of the data will reside in Objectivity databases accessible via the Advanced Multi-threaded Sewer (AMS). To date, over 70TB of data have been placed in Objectivity/DB, making it one of the largest databases in the world. Providing access to such a large quantity of data through a database sewer is a daunting task. A full-scale testbed environment had to be developed to tune various software parameters and a fundamental change had to occur in the AMS architecture to allow it to scale past several hundred terabytes of data. Additionally, several protocol extensions had to be implemented to provide practical access to large quantities of data. This paper will describe the design of the database and the changes that,ve needed to make in the AMS for scalability reasons and how the lessons we learned would be applicable to virtually, and kind of database sewer seeking to operate in the Petabyte region. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Becla, J (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0784-0 PY 2000 BP 271 EP 278 DI 10.1109/HPDC.2000.868659 PG 8 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BQ76L UT WOS:000089454200031 ER PT B AU Burris, RD Million, DL White, SR Gleicher, MK Holmes, HH AF Burris, RD Million, DL White, SR Gleicher, MK Holmes, HH GP IEEE IEEE TI Probe - A distributed storage testbed SO NINTH INTERNATIONAL SYMPOSIUM ON HIGH-PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 9th IEEE International Symposium on High Performance Distributed Computing CY AUG 01-04, 2000 CL PITTSBURGH, PA SP IEEE, Comp Soc Tech Comm Distrib Proc, Univ Arizonia, Dept ECE, Carnegie Mellon Univ, Argonne Natl Lab, Pittsburgh Supercomp Ctr AB As computers become more capable, researchers of all types are finding it necessary to store massive quantities of data generated by simulations or experiments and to retrieve them at high rare for analysis or visualization. Strong needs have arisen for storage systems tuned for particular needs, significant improvements in storage speed and access control; optimized wide-area-network bulk transfers; utilization of nerv media and new types of storage devices; and development, testing, and use of user written storage applications. The Oak Ridge National Laboratory (ORNL) and the National Energy Research Scientific Computing Center (NERSC) have formed a wide-area distributed testbed -- titled "Probe" -- to support challenging storage-related studies. C1 Oak Ridge Natl Lab, Div Comp Sci & Math, Oak Ridge, TN 37831 USA. RP Burris, RD (reprint author), Oak Ridge Natl Lab, Div Comp Sci & Math, Oak Ridge, TN 37831 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0784-0 PY 2000 BP 294 EP 295 DI 10.1109/HPDC.2000.868664 PG 2 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BQ76L UT WOS:000089454200036 ER PT B AU Terekhov, I White, V AF Terekhov, I White, V GP IEEE IEEE TI Distributed data access in the Sequential Access Model at the D0 experiment at Fermilab SO NINTH INTERNATIONAL SYMPOSIUM ON HIGH-PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 9th IEEE International Symposium on High Performance Distributed Computing CY AUG 01-04, 2000 CL PITTSBURGH, PA SP IEEE, Comp Soc Tech Comm Distrib Proc, Univ Arizonia, Dept ECE, Carnegie Mellon Univ, Argonne Natl Lab, Pittsburgh Supercomp Ctr C1 Fermi Natl Accelerator Lab, SAM Project 1, Batavia, IL 60510 USA. RP Terekhov, I (reprint author), Fermi Natl Accelerator Lab, SAM Project 1, POB 500, Batavia, IL 60510 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0784-0 PY 2000 BP 310 EP 311 DI 10.1109/HPDC.2000.868672 PG 2 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BQ76L UT WOS:000089454200044 ER PT J AU Larson-Meyer, DE Newcomer, BR Hunter, GR Hetherington, HP Weinsier, RL AF Larson-Meyer, DE Newcomer, BR Hunter, GR Hetherington, HP Weinsier, RL TI P-31 MRS measurement of mitochondrial function in skeletal muscle: reliability, force-level sensitivity and relation to whole body maximal oxygen uptake SO NMR IN BIOMEDICINE LA English DT Article DE muscle metabolism; oxidative capacity; reproducibility; validity; methodology ID MAGNETIC-RESONANCE SPECTROSCOPY; OXIDATIVE-METABOLISM; FIBER COMPOSITION; PRODUCTION-RATES; CREATINE-KINASE; ATP UTILIZATION; TIME COURSE; IN-VIVO; EXERCISE; RECOVERY AB The reliability, relation to whole-body maximal oxygen uptake (VO2max), and force-level sensitivity of P-31 MRS markers of mitochondrial function were studied in 39 normal-weight women. Following 90 s isometric plantar-flexion exercises at 45, 70 and 100% of maximum voluntary contraction, skeletal muscle mitochondrial function was determined from the phosphocreatine recovery time constant (TCPCr), the ADP recovery time constant (TCADP), and the rate of change in PCr during the first 14 s of recovery (OxPhos). VO2max was measured on a treadmill. Test-retest measurements were obtained in a subset of seven women. Overall, TCPCr, TCADP and OxPhos were reproducible for all exercises (coefficients of variation = 2.3-19.3%). With increasing force-level, TCPCr was prolonged (29.0 +/- 8.2, 31.9 +/- 9.0 and 35.4 +/- 9.5 s), OxPhos was increased (0.159 +/- 0.081, 0.247 +/- 0.090 and 0.310 +/- 0.114), and TCADP was Shortened (22.4 +/- 7.9, 21.3 +/- 6.2, and 19.5 +/- 6.7; p < 0.01). All MRS markers of mitochondrial function were correlated with VO2max (r=0.41-0.72; p<0.05). These results suggest that measurements of TCPCr, TCADP and OxPhos yield reproducible results that correlate with whole-body VO2max and that vary in force-level sensitivity. Copyright (C) 2000 John Wiley & Sons, Ltd. C1 Univ Alabama, Dept Nutr Sci, Div Physiol & Metab, Birmingham, AL 35205 USA. Univ Alabama, Dept Crit & Diagnost Care, Birmingham, AL 35205 USA. Univ Alabama, Dept Human Studies, Birmingham, AL 35205 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Larson-Meyer, DE (reprint author), Univ Alabama, Dept Nutr Sci, Div Physiol & Metab, 1675 Univ Blvd, Birmingham, AL 35205 USA. FU NCRR NIH HHS [RR 11811]; NIDDK NIH HHS [R01 DK-51684, R01 DK-49779] NR 45 TC 45 Z9 47 U1 0 U2 2 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0952-3480 J9 NMR BIOMED JI NMR Biomed. PD JAN PY 2000 VL 13 IS 1 BP 14 EP 27 DI 10.1002/(SICI)1099-1492(200002)13:1<14::AID-NBM605>3.0.CO;2-0 PG 14 WC Biophysics; Radiology, Nuclear Medicine & Medical Imaging; Spectroscopy SC Biophysics; Radiology, Nuclear Medicine & Medical Imaging; Spectroscopy GA 291NR UT WOS:000085743400003 PM 10668050 ER PT B AU Streets, DG Waldhoff, ST AF Streets, DG Waldhoff, ST BE VanHam, J Baede, APM Meyer, LA Ybema, R TI Greenhouse-gas emissions from biofuel use in Asia SO NON-CO2 GREENHOUSE GASES: SCIENTIFIC UNDERSTANDING, CONTROL AND IMPLEMENTATION LA English DT Proceedings Paper CT 2nd International Symposium on Non-CO2 Greenhouse Gases - Scientific Understanding, Control and Implementation CY SEP 08-10, 1999 CL NOORDWIJKERHOUT, NETHERLANDS SP Vereniging van Milieukundigen, Netherlands Assoc Environm Profess, European Federat Clean Air, Environm Protect Assoc, UN Intergovt Panel Climate Change, Minist Housing, Spatial Planning & Environm Netherlands, US EPA, Int Global Atmospher Chem Panel IGBP, Eurotrac 2, Commiss European Union, UN FAO DE biofuels; Asia; greenhouse gas; global waning; emissions ID BIOMASS AB Biomass is a primary fuel for much of the world's population. In some developing countries it can contribute 80-90% of total primary energy consumption. In Asia as a whole we estimate that biomass contributes about 22 EJ, almost 24% of total energy use. Much of this biomass is combusted in inefficient domestic stoves and cookers, enhancing the formation of products of incomplete combustion (PIC), many of which are greenhouse gases. An inventory of the combustion of biofuels (fuelwood, crop residues, and dried animal waste) in Asia is used to develop estimates of the emissions of carbon-containing greenhouse gases (CO2, CO, CH4, and NMHC) in Asian countries. The data are examined from two perspectives: total carbon released and total global warming potential (GWP) of the gases. We estimate that biofuels contributed 573 Tg-C in 1990, about 28% of the total carbon emissions from energy use in Asia. China (259 Tg-C) and India (187 Tg-C) were the largest emitting countries by far. The majority of the emissions, 504 Tg-C, are in the form of CO2; however, emissions of non-CO2 greenhouse gases are significant: 57 Tg-C as CO, 6.4 Tg-C as CH4, and 5.9 Tg-C as NMHC. Because of the high rate of incomplete combustion in typical biofuel stoves and the high GWP coefficients of the products of incomplete combustion, PIC comprise an even larger share of biofuel emissions when measured in terms of global warming potential (in CO2 equivalents): 48% over a 20-year time frame and 26% over 100 years. Even when the biofuel is assumed to be harvested on a completely sustainable basis (all CO2 emissions are reabsorbed in the following growing season), PIC emissions from biofuel combustion account for almost 5% of total carbon emissions (including emissions from fossil-fuel combustion) and nearly 25% of CO2 equivalents in terms of shortterm (20-year) GWP. C1 Argonne Natl Lab, Decis & Informat Sci Div, Argonne, IL 60439 USA. RP Streets, DG (reprint author), Argonne Natl Lab, Decis & Informat Sci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6199-7 PY 2000 BP 247 EP 254 PG 8 WC Environmental Sciences SC Environmental Sciences & Ecology GA BQ80J UT WOS:000089620400042 ER PT S AU Burnett, GC McCallen, DB Noble, CR AF Burnett, GC McCallen, DB Noble, CR BE Aktan, EM Gosselin, SR TI Updating FEM using state-space based signal processing techniques SO NONDESTRUCTIVE EVALUATION OF HIGHWAYS, UTILITIES, AND PIPELINES IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nondestructive Evaluation of Highways, Utilities, and Pipelines IV CY MAR 07-09, 2000 CL NEWPORT BEACH, CA SP Int Soc Opt Engn DE state space; parameter identification; non-destructive evaluation; extended Kalman filter; Gauss-Newton AB Until recently, attempts to update Finite Element Models (FEM) of targe structures based upon recording structural motions were mostly ad hoc, requiring a large amount of engineering experience and skill. Studies have been undertaken at LLNL to use state-space based signal processing techniques to locate the existence and type of model mismatches common in FEM. Two different methods (Gauss-Newton gradient search and extended Kalman filter) will be explored, and the preliminary results from a simulated 10 degree of freedom (DOF) building model will be discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Burnett, GC (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-290, Livermore, CA 94550 USA. NR 3 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 0-8194-3613-5 J9 P SOC PHOTO-OPT INS PY 2000 VL 3995 BP 37 EP 43 DI 10.1117/12.387828 PG 3 WC Engineering, Civil; Instruments & Instrumentation; Materials Science, Characterization & Testing SC Engineering; Instruments & Instrumentation; Materials Science GA BQ47D UT WOS:000088436600004 ER PT S AU Doctor, SR Schuster, GJ Simonen, FA AF Doctor, SR Schuster, GJ Simonen, FA BE Aktan, EM Gosselin, SR TI Density and distribution of fabrication flaws in the shoreham reactor vessel SO NONDESTRUCTIVE EVALUATION OF HIGHWAYS, UTILITIES, AND PIPELINES IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nondestructive Evaluation of Highways, Utilities, and Pipelines IV CY MAR 07-09, 2000 CL NEWPORT BEACH, CA SP Int Soc Opt Engn AB The Pacific Northwest National Laboratory (PNNL) has been conducting a multi-year program for the U.S. Nuclear Regulatory Commission (NRC), Office of Nuclear Regulatory Research on the effectiveness of NDE for inspection of nuclear power plants. One task of this program concerns the development of generic flaw density and distribution functions for fabrication flaws in reactor pressure vessels. Reactor pressure vessel material from the cancelled Shoreham nuclear power plant was obtained as a part of a joint program between the NRC, Baltimore Gas and Electric and the Electric Power Research Institute. PNNL has conducted NDE inspections of this material and has estimated the density and distributions of fabrication flaws in this material. This paper discusses these inspections and the results of analyzing this inspection data. More than 4,000 fabrication flaws were detected and are described in this paper. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Doctor, SR (reprint author), Battelle Mem Inst, Pacific NW Labs, 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 0-8194-3613-5 J9 P SOC PHOTO-OPT INS PY 2000 VL 3995 BP 512 EP 522 DI 10.1117/12.387844 PG 3 WC Engineering, Civil; Instruments & Instrumentation; Materials Science, Characterization & Testing SC Engineering; Instruments & Instrumentation; Materials Science GA BQ47D UT WOS:000088436600050 ER PT S AU Jarrell, D AF Jarrell, D BE Aktan, EM Gosselin, SR TI An information architecture for coping with aging infrastructure SO NONDESTRUCTIVE EVALUATION OF HIGHWAYS, UTILITIES, AND PIPELINES IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nondestructive Evaluation of Highways, Utilities, and Pipelines IV CY MAR 07-09, 2000 CL NEWPORT BEACH, CA SP Int Soc Opt Engn AB Pacific Northwest National Laboratory personnel have developed a cost-effective solution for implementing the use of advanced technologies for monitoring the condition and performance of aging industrial facilities. A combination of operations and maintenance (O&M) know-how together with Laboratory technical capabilities have been used to develop and demonstrate the effectiveness of a condition monitoring software system. Already proven in a moderate size pilot heating plant, the system is expected to pay large dividends in the reduction of O&M costs in an aging cogeneration facility. Additional projects are currently underway to develop this technology to its full potential. This advanced architecture was designed to provide each segment of the plant operations and maintenance (O&M) team with understandable information for making safe, cost-effective life-cycle operating decisions. The software will provide plant operators, maintenance technicians, engineering staff and administrators with on-target, on-line information that enables high process efficiency simultaneously with cost-effective, life cycle oriented, capital equipment management. This infrastructure information becomes increasingly critical as the equipment, systems, and the facility itself become older. The result of this research provides the O&M practitioner with the ability to intelligently select the asset management course of action that minimizes both the cost and risk engendered by the operation and maintenance of aging process facilities. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Jarrell, D (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999, Richland, WA 99352 USA. RI Johnson, Marilyn/E-7209-2011 NR 1 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 0-8194-3613-5 J9 P SOC PHOTO-OPT INS PY 2000 VL 3995 BP 524 EP 536 DI 10.1117/12.387846 PG 3 WC Engineering, Civil; Instruments & Instrumentation; Materials Science, Characterization & Testing SC Engineering; Instruments & Instrumentation; Materials Science GA BQ47D UT WOS:000088436600051 ER PT S AU Good, MS Harris, RV Skorpik, JR Pardini, AF Smith, CM Bowey, RE Diaz, AA Burghard, BJ Judd, KM Adamson, JD AF Good, MS Harris, RV Skorpik, JR Pardini, AF Smith, CM Bowey, RE Diaz, AA Burghard, BJ Judd, KM Adamson, JD BE Aktan, EM Gosselin, SR TI Development of enhanced ultrasonic imaging for in situ inspection of a tension-stressed, threaded fastener SO NONDESTRUCTIVE EVALUATION OF HIGHWAYS, UTILITIES, AND PIPELINES IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nondestructive Evaluation of Highways, Utilities, and Pipelines IV CY MAR 07-09, 2000 CL NEWPORT BEACH, CA SP Int Soc Opt Engn DE fastener; bolt; stud; ultrasonic inspection; in situ inspection; crack; thread root; volumetric imaging; tone-burst ID WAVE AB A laboratory system was developed that utilized an ultrasonic pulse-echo technique to detect very small cracks emanating from the thread root of a tensile-stressed fastener Primary benefits were 1) the ability to inspect the fastener without its removal from the structure, 2) much improved detection sensitivity to small cracks, and 3) easy interpretation of data. The fastener of interest had threads with nominal inner and outer diameters of 1.8 cm (0.73 in.) and 2.2 cm (0.86 in.), respectively, and a thread pitch of 3.1 threads per centimeter (8.0 threads per in). A plastic washer was placed over the fastener nut to shield the nut from ultrasound and thereby eliminate spurious signals. B-scan images provided feedback to align the ultrasonic scanner and fastener for optimal detection sensitivity. A tone-burst pulser-receiver controlled excitation frequency and bandwidth to maintain focal properties, minimize backscatter noise from the base material, and increase penetration into the coarse-grained Inconel. A custom ultrasonic transducer was used to optimize the focal properties over the inspection zone of 2.3 cm to 3.3 cm (0.9 in, to 1.3 in) from the threaded end of the fastener A calibration part with four 1.0-mm (0.040-in) deep notches spanning the length of the inspection zone was used to calibrate distance-amplitude correction and system sensitivity. Custom B-scan and C-scan views were used to present data to the inspector and optimize the signal-to-noise ratio. A direct comparison was made between ultrasonic and destructive test images. Details of system hardware, data-acquisition procedure, analysis, and plans for a portable hand-held system for field inspection are provided. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Good, MS (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999,MSIN K5-26, Richland, WA 99352 USA. OI Adamson, Justus/0000-0002-7868-5631 NR 6 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3613-5 J9 P SOC PHOTO-OPT INS PY 2000 VL 3995 BP 590 EP 599 DI 10.1117/12.387852 PG 4 WC Engineering, Civil; Instruments & Instrumentation; Materials Science, Characterization & Testing SC Engineering; Instruments & Instrumentation; Materials Science GA BQ47D UT WOS:000088436600057 ER PT S AU Kinney, JH Haupt, DL Lemay, JD AF Kinney, JH Haupt, DL Lemay, JD BE Baaklini, GY Meyendorf, N Matikas, TE Gilmore, RS TI Three-dimensional, nondestructive imaging of low density materials SO NONDESTRUCTIVE METHODS FOR MATERIALS CHARACTERIZATION SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nondestructive Methods for Materials Characterization held at the 1999 MRS Fall Meeting CY NOV 29-30, 1999 CL BOSTON, MA SP Mat Res Soc AB The goal of this study was to develop a three-dimensional imaging method for studies of deformation in low-density materials during loading, and to implement finite element solutions of the elastic equations based on the images. Specimens of silica-reinforced polysiloxane foam pads, 15 mm in diameter by 1 mm thick, were used for this study. The nominal pore density was 50%, and the pores approximated interconnected spheres. The specimens were imaged with microtomography at similar to 16 mu m resolution. A rotating stage with micrometer driven compression allowed imaging of the foams during deformation with precise registration of the images. A finite element mesh, generated from the image voxels, was used to calculate the mechanical properties of the structure, and the results were compared with conventional mechanical testing. The foam exhibited significant nonlinear behavior with compressive loading. The finite-element calculations from the images, which were in excellent agreement with experimental data, suggested that nonlinear behavior in the load displacement curves arises from buckling of the cell walls during compression and not from any nonlinear properties of the base elastomer. High-resolution microtomography, coupled with efficient finite-element modeling, shows promise for improving our understanding of the deformation behavior of cellular materials. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Kinney, JH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 6 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 1-55899-499-8 J9 MATER RES SOC SYMP P PY 2000 VL 591 BP 19 EP 24 PG 6 WC Materials Science, Characterization & Testing SC Materials Science GA BQ35B UT WOS:000088094200003 ER PT S AU Swift, GW AF Swift, GW BE Lauterborn, W Kurz, T TI Streaming in thermoacoustic engines and refrigerators SO NONLINEAR ACOUSTICS AT THE TURN OF THE MILLENNIUM SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Symposium on Nonlinear Acoustics CY SEP 01-04, 1999 CL GOTTINGEN, GERMANY SP Int Union Pure & Appl Phys, Deutsch Forsch Gemeinsch, WE Heraeus Stiftung, State Niedersachsen ID PULSE TUBE REFRIGERATORS AB The efficiency of thermoacoustic engines and refrigerators is now approaching 40% of the ideal efficiency allowed by the laws of thermodynamics. To achieve such high efficiency requires understanding and control of streaming. Sometimes, thermoacoustic phenomena cause unwanted streaming-driven convection of heat, which we strive to eliminate; in other cases, deliberate use of second-order mass flow may be the key to simplification and improved efficiency. Some features of this streaming are quantitatively understood, but many issues must still be resolved before thermoacoustic devices reach their full potential. C1 Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. RP Swift, GW (reprint author), Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. NR 12 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-945-9 J9 AIP CONF PROC PY 2000 VL 524 BP 105 EP 114 PG 10 WC Acoustics; Mechanics; Physics, Fluids & Plasmas SC Acoustics; Mechanics; Physics GA BQ75G UT WOS:000089403000011 ER PT S AU Johnson, PA Guyer, RA Ostrovsky, LA AF Johnson, PA Guyer, RA Ostrovsky, LA BE Lauterborn, W Kurz, T TI A nonlinear mesoscopic elastic class of materials SO NONLINEAR ACOUSTICS AT THE TURN OF THE MILLENNIUM SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Symposium on Nonlinear Acoustics CY SEP 01-04, 1999 CL GOTTINGEN, GERMANY SP Int Union Pure & Appl Phys, Deutsch Forsch Gemeinsch, WE Heraeus Stiftung, State Niedersachsen AB It is becoming clear that the elastic properties of rock are shared by numerous other materials (sand, soil, some ceramics, concrete, etc.). These materials have one or more of the following properties in common: strong nonlinearity, hysteresis in stress-strain relation, slow dynamics and discrete memory. Primarily, it is the material's compliance, the mesoscopic linkages between the rigid components, that give these materials their unusual elastic properties. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Johnson, PA (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop D443, Los Alamos, NM 87545 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 1-56396-945-9 J9 AIP CONF PROC PY 2000 VL 524 BP 291 EP 294 PG 4 WC Acoustics; Mechanics; Physics, Fluids & Plasmas SC Acoustics; Mechanics; Physics GA BQ75G UT WOS:000089403000052 ER PT S AU TenCate, JA Smith, E Byers, LW Shankland, TJ AF TenCate, JA Smith, E Byers, LW Shankland, TJ BE Lauterborn, W Kurz, T TI Slow dynamics experiments in solids with nonlinear mesoscopic elasticity SO NONLINEAR ACOUSTICS AT THE TURN OF THE MILLENNIUM SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Symposium on Nonlinear Acoustics CY SEP 01-04, 1999 CL GOTTINGEN, GERMANY SP Int Union Pure & Appl Phys, Deutsch Forsch Gemeinsch, WE Heraeus Stiftung, State Niedersachsen AB As revealed by longitudinal bar resonance experiments, materials such as rocks and concrete show a rich diversity of nonlinear elastic behavior. As a function of increasing drive level, resonance frequencies shift downward by several percent, the resonant line shape changes, and harmonics and slow dynamics appear. Slow dynamics [1] refers to the time-dependent recovery of an elastic modulus to its initial value after being softened by large strain. In order to explore the mechanisms of nonlinear response including slow dynamics, we performed experiments on concrete and several different earth materials. The softening (conditioning) and recovery processes appear to be asymmetric. Conditioning takes place quickly; full recovery of the elastic modulus las measured by drift of the resonance peak) takes minutes to hours, depending on the length of time the conditioning strain was applied. We find that for a wide variety of rocks and concretes, the recovery of the resonant frequency goes as log(time). Logarithmic time-dependence is a phenomenon associated with static friction and restoration of surface contacts, which in rocks probably takes place at touching crack surfaces. C1 Univ Calif Los Alamos Natl Lab, Los Alamos Seism Res Ctr, Los Alamos, NM 87545 USA. RP TenCate, JA (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos Seism Res Ctr, EES-4, Los Alamos, NM 87545 USA. NR 4 TC 7 Z9 7 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 1-56396-945-9 J9 AIP CONF PROC PY 2000 VL 524 BP 303 EP 306 PG 4 WC Acoustics; Mechanics; Physics, Fluids & Plasmas SC Acoustics; Mechanics; Physics GA BQ75G UT WOS:000089403000055 ER PT S AU Smith, AV AF Smith, AV BE Pierce, JW TI How to select nonlinear crystals and model their performance using SNLO software SO NONLINEAR MATERIALS DEVICES, AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nonlinear Materials, Devices, and Applications CY JAN 24-25, 2000 CL SAN JOSE, CA SP SPIE DE optical parametric mixing; optical parametric oscillator; nonlinear crystals; nonlinear optics software ID OPTICAL PARAMETRIC OSCILLATOR AB SNLO is public domain software developed at Sandia Nat. Labs. It is intended to assist in the selection of the best nonlinear crystal for a particular application, and in predicting its performance. This paper briefly describes its functions and how to use them. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Smith, AV (reprint author), Sandia Natl Labs, MS 1423, Albuquerque, NM 87185 USA. NR 4 TC 14 Z9 14 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 0-8194-3545-7 J9 P SOC PHOTO-OPT INS PY 2000 VL 3928 BP 62 EP 69 DI 10.1117/12.379931 PG 8 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BP95E UT WOS:000086713800009 ER PT S AU Tretiak, S Chernyak, V Mukamel, S AF Tretiak, S Chernyak, V Mukamel, S GP OSA OSA OSA TI Origin, scaling, and saturation of nonlinear polarizabilities in donor/acceptor polymers SO NONLINEAR OPTICS: MATERIALS, FUNDAMENTALS, AND APPLICATIONS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Conference on Nonlinear Optics: Materials, Fundamentals, and Applications, Technical Digest CY AUG 06-10, 2000 CL KAUA I-LIHUE, HI SP Opt Soc Amer, IEEE, Lasers & ElectroOpt Soc ID OPTICAL NONLINEARITIES; CONJUGATED MOLECULES; EXCITATIONS; POLYENES; DESIGN AB The size-scaling of polarizabilities of donor/acceptor substituted polymers is investigated. The second order nonlinearity saturates to a constant value, independent on molecular size, whereas the linear and cubic polarizabilities grow linearly with size. (C) 1999 Optical Society of America. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Tretiak, S (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Tretiak, Sergei/B-5556-2009 OI Tretiak, Sergei/0000-0001-5547-3647 NR 13 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-646-X J9 OSA TRENDS OPT PHOTO PY 2000 VL 46 BP 10 EP 11 DI 10.1109/NLO.2000.883557 PG 2 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BR02P UT WOS:000165407100002 ER PT S AU Lee, HWH Taylor, BR Kauzlarich, SM AF Lee, HWH Taylor, BR Kauzlarich, SM GP OSA OSA OSA TI Nonlinear optical properties and applications of silicon and germanium quantum dot nanocomposites SO NONLINEAR OPTICS: MATERIALS, FUNDAMENTALS, AND APPLICATIONS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Conference on Nonlinear Optics: Materials, Fundamentals, and Applications, Technical Digest CY AUG 06-10, 2000 CL KAUA I-LIHUE, HI SP Opt Soc Amer, IEEE, Lasers & ElectroOpt Soc AB We report on the characterization of the dispersion and temporal response of the complex third order nonlinear optical properties of silicon and germanium quantum dot nanocomposites and its dependence on the nature of the nanocomposite. (C) 1999 Optical Society of America. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Lee, HWH (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,Mail Stop L-174, Livermore, CA 94551 USA. RI Kauzlarich, Susan/H-1439-2011 NR 4 TC 4 Z9 4 U1 1 U2 2 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-646-X J9 OSA TRENDS OPT PHOTO PY 2000 VL 46 BP 12 EP 13 DI 10.1109/NLO.2000.883558 PG 2 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BR02P UT WOS:000165407100003 ER PT S AU Klimov, V Mikhailovsky, A Xu, S Malko, A Leatherdale, C Bawendi, M AF Klimov, V Mikhailovsky, A Xu, S Malko, A Leatherdale, C Bawendi, M GP OSA OSA OSA TI Carrier relaxation dynamics and ultrafast optical nonlinearities in semiconductor quantum dots SO NONLINEAR OPTICS: MATERIALS, FUNDAMENTALS, AND APPLICATIONS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Conference on Nonlinear Optics: Materials, Fundamentals, and Applications, Technical Digest CY AUG 06-10, 2000 CL KAUA I-LIHUE, HI SP Opt Soc Amer, IEEE, Lasers & ElectroOpt Soc ID ELECTRON AB We use a variety of femtosecond nonlinear optical techniques to study carrier relaxation and mechanisms for resonant optical nonlinearities in semiconductor quantum dots. Combining femtosecond inter- and intra-band probes we are able to separate electron and hole relaxation paths and to resolve single exponential dynamics of different multiparticle states. (C)1999 Optical Society of America. C1 Univ Calif Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RP Klimov, V (reprint author), Univ Calif Los Alamos Natl Lab, Div Chem, C-6,MS J585, Los Alamos, NM 87545 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-646-X J9 OSA TRENDS OPT PHOTO PY 2000 VL 46 BP 140 EP 142 DI 10.1109/NLO.2000.883602 PG 3 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BR02P UT WOS:000165407100044 ER PT S AU Omenetto, FG Yarotski, D Luce, B Taylor, AJ AF Omenetto, FG Yarotski, D Luce, B Taylor, AJ GP OSA OSA OSA TI Ultrashort pulses in optical fibers SO NONLINEAR OPTICS: MATERIALS, FUNDAMENTALS, AND APPLICATIONS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Conference on Nonlinear Optics: Materials, Fundamentals, and Applications, Technical Digest CY AUG 06-10, 2000 CL KAUA I-LIHUE, HI SP Opt Soc Amer, IEEE, Lasers & ElectroOpt Soc ID MU-M; FREQUENCY AB Phase analysis of femtosecond pulse propagation in fibers is presented. Observation and characterization of pulse evolution as a function of energy, distance, soliton formation and soliton self-frequency shift are described. (C) 1999 Optical Society of America OCIS codes: (320.7100)Ultrafast optics, (060.7140), (320.7140), Ultrafast processes in fibers, (320.5550) Pulses. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Omenetto, FG (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MST-10,MSK764, Los Alamos, NM 87545 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-646-X J9 OSA TRENDS OPT PHOTO PY 2000 VL 46 BP 307 EP 309 DI 10.1109/NLO.2000.883657 PG 3 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BR02P UT WOS:000165407100096 ER PT S AU Mertens, FG Bishop, AR AF Mertens, Franz G. Bishop, Alan R. BE Christiansen, PL Sorensen, MP Scott, AC TI Dynamics of Vortices in Two-Dimensional Magnets SO NONLINEAR SCIENCE AT THE DAWN OF THE 21ST CENTURY SE Lecture Notes in Physics LA English DT Article; Book Chapter ID EASY-PLANE FERROMAGNETS; ANISOTROPIC HEISENBERG-MODEL; NEUTRON-SCATTERING; METASTABLE STATES; SPIN-DYNAMICS; VORTEX PAIRS; XY-MODEL; ANTIFERROMAGNETS; EXCITATIONS; EQUATIONS AB Theories, simulations and experiments on vortex dynamics in quasi-two-dimensional magnetic materials are reviewed. These materials can be modelled by the classical two-dimensional anisotropic Heisenberg model with XY (easy-plane) symmetry. There are two types of vortices, characterized by their polarization (a second topological charge in addition to the vorticity): Planar vortices have Newtonian dynamics (even-order equations of motion) and exhibit strong discreteness effects, while non-planar vortices have non-Newtonian dynamics (odd-order equations of motion) and smooth trajectories. These results are obtained by a collective variable theory based on a generalized travelling wave ansatz which allows a dependence of the vortex shape on velocity, acceleration etc.. An alternative approach is also reviewed and compared, namely the coupling of the vortex motion to certain quasi-local spinwave modes. The influence of thermal fluctuations on single vortices is investigated. Different types of noise and damping are discussed and implemented into the microscopic equations which yields stochastic equations of motion for the vortices. The stochastic forces can be explicitly calculated and a vortex diffusion constant is defined. The solutions of the stochastic equations are compared with Langevin dynamics simulations. Moreover, noise-induced transitions between opposite polarizations of a vortex are investigated. For temperatures above the Kosterlitz-Thouless vortex-antivortex unbinding transition, a phenomenological theory, namely the vortex gas approach, yields central peaks in the dynamic form factors for the spin correlations. Such peaks are observed both in combined Monte Carlo- and Spin Dynamics-Simulations and in inelastic neutron scattering experiments. However, the assumption of ballistic vortex motion appears questionable. C1 [Mertens, Franz G.] Univ Bayreuth, Phys Inst, Lehrstuhl Theoret Phys 1, D-8580 Bayreuth, Germany. [Bishop, Alan R.] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. [Bishop, Alan R.] Los Alamos Natl Lab, CNLS, Los Alamos, NM 87545 USA. RP Mertens, FG (reprint author), Univ Bayreuth, Phys Inst, Lehrstuhl Theoret Phys 1, Postfach 101251, D-8580 Bayreuth, Germany. NR 77 TC 5 Z9 5 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0075-8450 BN 978-3-540-66918-0 J9 LECT NOTES PHYS PY 2000 VL 542 BP 137 EP 170 D2 10.1007/3-540-46629-0 PG 34 WC Optics; Physics, Multidisciplinary; Physics, Mathematical SC Optics; Physics GA BSE15 UT WOS:000284263600007 ER PT J AU Hibiki, T Ishii, M AF Hibiki, T Ishii, M TI Experimental study on hot-leg U-bend two-phase natural circulation in a loop with a large diameter pipe SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article AB In relation to nuclear reactor accident and safety studies, experiments on hot-leg U-bend two-phase natural circulation in a loop with a relatively large diameter pipe (10.2 cm inner diameter) were performed for understandings the two-phase natural circulation and flow termination during a small break loss of coolant accident in LWRs. The loop design was based on the scaling criteria developed under this program and the loop was operated either in a natural circulation mode or in a forced circulation mode using nitrogen gas and water. Various tests were carried out to establish the basic mechanism of the flow termination as well as to obtain essential information on scale effects of various parameters such as the loop frictional resistance, thermal center and pipe diameter. The void distribution in a hot-leg, flow regime and natural circulation rate were measured in detail for various conditions. The termination of the natural circulation occurred when there was insufficient hydrostatic head in the downcomer side. The superficial gas velocity at the flow termination could be predicted well by the simple model derived from a force balance between the frictional pressure drop along the loop and the hydrostatic head difference. The bubbly-to-slug flow transition was found to be dependent on axial locations. It turned out that the formation of cap bubbles in the large diameter pipe caused the increased drift velocity, which would affect the prediction of the void fraction in the hot leg. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Kyoto Univ, Inst Res Reactor, Osaka 5900494, Japan. Argonne Natl Lab, Reactor Anal & Safety Div, Argonne, IL 60439 USA. RP Ishii, M (reprint author), Purdue Univ, Sch Nucl Engn, W Lafayette, IN 47907 USA. RI Hibiki, Takashi /B-6923-2017 OI Hibiki, Takashi /0000-0002-4138-7286 NR 18 TC 14 Z9 14 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0029-5493 J9 NUCL ENG DES JI Nucl. Eng. Des. PD JAN PY 2000 VL 195 IS 1 BP 69 EP 84 DI 10.1016/S0029-5493(99)00176-4 PG 16 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 275ZX UT WOS:000084852100006 ER PT J AU Perkins, LJ Logan, BG Rosen, MD Perry, MD de la Rubia, TD Ghoniem, NM Ditmire, T Springer, PT Wilks, SC AF Perkins, LJ Logan, BG Rosen, MD Perry, MD de la Rubia, TD Ghoniem, NM Ditmire, T Springer, PT Wilks, SC TI The investigation of high intensity laser driven micro neutron sources for fusion materials research at high fluence SO NUCLEAR FUSION LA English DT Article ID SOLID-DENSITY TARGETS; DEFECT PRODUCTION; SUBPICOSECOND LASERS; PLASMA INTERACTIONS; ELEMENTAL METALS; ATOMIC CLUSTERS; ABSORPTION; IRRADIATION; ENERGY; PULSES AB The application of fast pulse, high intensity lasers to drive low cost DT point neutron sources for fusion materials testing at high flux/fluence is investigated. At present, high power benchtop lasers with intensities of 10(18) W/cm(2) are routinely employed and systems capable of greater than or equal to 10(21) W/cm(2) are becoming available. These potentially offer sufficient energy density for efficient neutron production in DT targets with dimensions of around 100 mu m. Two different target concepts are analysed - a hot ion, beam-target system and an exploding pusher target system - and neutron emission rates are evaluated as a function of laser and target conditions. Compared with conventional beam-target neutron sources with steady state liquid cooling, the driver energy here is removed by sacrificial vaporization of a small target spot. The resulting small source volumes offer the potential for a low cost, high flux source of 14 MeV neutrons at close coupled, micro (less than or equal to 1 mm) test specimens. In particular, it is shown that a laser driven target with similar to 100 J/pulse at 100 Hz (i.e. similar to 10 kW average power) and laser irradiances in the range I lambda(2) similar to 10(17) - 10(19) W mu m(2)/cm(2) could produce primary, uncollided neutron fluxes at the test specimen in the 10(14)-10(15) n cm(-2) s(-2) range. While focusing on the laser-plasma interaction physics and resulting neutron production, the materials science required to validate computational damage models utilizing greater than or equal to 100 dpa irradiation of such specimens is also examined; this may provide a multiscale predictive capability for the behaviour of engineering scale components in fusion reactor applications. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Los Angeles, Los Angeles, CA USA. RP Perkins, LJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RI Ghoniem, Nasr/A-9799-2008 NR 64 TC 53 Z9 55 U1 1 U2 10 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 2000 VL 40 IS 1 BP 1 EP 19 DI 10.1088/0029-5515/40/1/301 PG 19 WC Physics, Fluids & Plasmas SC Physics GA 285YN UT WOS:000085416100001 ER PT J AU Zweben, SJ Budny, RV Darrow, DS Medley, SS Nazikian, R Stratton, BC Synakowski, EJ Taylor, G AF Zweben, SJ Budny, RV Darrow, DS Medley, SS Nazikian, R Stratton, BC Synakowski, EJ Taylor, G CA TFTR Grp TI Alpha particle physics experiments in the Tokamak Fusion Test Reactor SO NUCLEAR FUSION LA English DT Review ID DEUTERIUM-TRITIUM PLASMAS; PELLET CHARGE-EXCHANGE; TOROIDAL ALFVEN EIGENMODES; ION-CYCLOTRON EMISSION; TFTR DT EXPERIMENTS; D-T OPERATION; REVERSED MAGNETIC SHEAR; CONFINED ALPHAS; SAWTOOTH OSCILLATIONS; PROFILE MEASUREMENTS AB Alpha particle physics experiments were done on TFTR during its DT run from 1993 to 1997. These experiments utilized several new alpha particle diagnostics and hundreds of DT discharges to characterize the alpha particle confinement and wave-particle interactions. In general, the results from the alpha particle diagnostics agreed with the classical single particle confinement model in MHD quiescent discharges. The alpha loss due to toroidal field ripple was identified in some cases, and the low radial diffusivity inferred for high energy alphas was consistent with orbit averaging over small scale turbulence. Finally, the observed alpha particle interactions with sawteeth, toroidal Alfven eigenmodes and ICRF waves were approximately consistent with theoretical modelling. What was learned is reviewed and what remains to be understood is identified. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Zweben, SJ (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. EM szweben@ppl.gov NR 188 TC 72 Z9 72 U1 3 U2 16 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD JAN PY 2000 VL 40 IS 1 BP 91 EP 149 DI 10.1088/0029-5515/40/1/307 PG 59 WC Physics, Fluids & Plasmas SC Physics GA 285YN UT WOS:000085416100007 ER PT J AU Byrd, JM Baptiste, K De Santis, S Kosta, S Lo, CC Plate, D Rimmer, RA Franks, M AF Byrd, JM Baptiste, K De Santis, S Kosta, S Lo, CC Plate, D Rimmer, RA Franks, M TI Design of a higher harmonic RF system for the Advanced Light Source SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE storage rings; radiofrequency cavities; Touschek lifetime; coupled bunch instabilities ID BUNCH AB We report on the design and fabrication of a third harmonic radiofrequency (RF) system for the Advanced Light Source (ALS) to be used for lengthening the bunch and increasing the Touschek-dominated beam lifetime. We plan to install five single-cell 1.5 GHz copper RF cavities in one-half of an ALS straight section with a predicted increase in the lifetime by a factor of 3. Each RF cell is designed to sustain a maximum voltage of 125 kV with a power dissipation of 5 kW. We present measurements made on an aluminum cavity model characterizing the RF properties of cavity such as the cavity R/Q and higher-order modes (HOMs). In particular, resonances in the cavity tuners were studied in order to avoid heating of the tuner bellows. Initial measurements of the copper cavities indicate a Q value of 21 000, resulting in a shunt impedance of 1.69 Mn per cell. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Byrd, JM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Mail Stop 80-1-101,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 14 TC 6 Z9 6 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 2000 VL 439 IS 1 BP 15 EP 25 DI 10.1016/S0168-9002(99)00892-X PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 270QH UT WOS:000084546700003 ER PT J AU Ukegawa, F Heinrich, JG Lockyer, NS Long, O Kononenko, W Gao, T Newcomer, FM Van Berg, R Kephart, R Mori, S Kondo, K AF Ukegawa, F Heinrich, JG Lockyer, NS Long, O Kononenko, W Gao, T Newcomer, FM Van Berg, R Kephart, R Mori, S Kondo, K TI Results from a 20 scintillator bar time-of-flight test system located inside the 1.4 T CDF solenoid SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE time-of-flight; CDF; particle identification; hodoscope; photomultiplier; scintillator ID SILICON VERTEX DETECTOR AB This paper reports on a test time-of-flight (TOF) system that operated in the Collider Detector at Fermilab (CDF) during pp Tevatron collider operation at root s = 1.8 TeV in the fall 1995 running period. The TOF system consisted of 20 130 x 4 x 4 cm(3) long Bicron BC408 scintillator bars, with each end of the bars fitted with a small compound parabolic concentrator and a 16-stage R5946 Hamamatsu fine-mesh photomultiplier. The electronics chain consisted of a custom designed preamplifier, constant fraction discriminator, and commercial TDC and ADC FASTBUS modules read out with the CDF data acquisition system. The counters were installed between the Central Tracking Chamber and the 1.4 T superconducting solenoid at a mean radius of 140 cm. We report a procedure for calculating the to time from all tracks in an event, the timing resolution, and the particle identification performance of this system. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Penn, Philadelphia, PA 19104 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Tsukuba, Tsukuba, Ibaraki 305, Japan. RP Lockyer, NS (reprint author), Univ Penn, Philadelphia, PA 19104 USA. NR 7 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 1 PY 2000 VL 439 IS 1 BP 65 EP 79 DI 10.1016/S0168-9002(99)00885-2 PG 15 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 270QH UT WOS:000084546700008 ER PT J AU Logan, J Fowler, JS Volkow, ND Wang, GJ MacGregor, RR Shea, C AF Logan, J Fowler, JS Volkow, ND Wang, GJ MacGregor, RR Shea, C TI Reproducibility of repeated measures of deuterium substituted [C-11]L-deprenyl ([C-11]L-deprenyl-D2) binding in the human brain SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE PET; monoamine oxidase; kinetic model; [C-11]L-deprenyl-D2 ID POSITRON EMISSION TOMOGRAPHY; MONOAMINE-OXIDASE-B; INHIBITION; PET AB The purpose of this study was to assess the reproducibility of repeated positron emission tomography (PET) measures of brain monoamine oxidase B (MAO B) using deuterium-substituted [C-11]L-deprenyl ([C-11]L-deprenyl-D2) in normal subjects and to validate the method used for estimating the kinetic constants from the irreversible 3-compartment model applied to the tracer binding, Five normal healthy subjects (age range 23-73 years) each received two PET scans with [C-11]L-deprenyl-D2, The time interval between scans was 7-27 days. Time-activity data from eight regions of interest and an arterial plasma input function was used to calculate lambda k(3), a model term proportional to MAO B, and K-1, the plasma to brain transfer constant that is related to blood flow. Linear (LIN) and nonlinear least-squares (NLLSR) estimation methods were used to calculate the optimum model constants, A comparison of time-activity curves for scan 1 and scan 2 showed that the percent of change for peak uptake varied from -18.5 to 15.0% and that increases and decreases in uptake on scan 2 were associated with increases and decreases in the value of the arterial input of the tracer. Calculation of lambda k(3) showed a difference between scan 1 and scan 2 in the global value ranging between -6.97 and 4.5% (average -2.1 +/- 4.7%). The average percent change for eight brain regions for the five subjects was -2.84 +/- 7.07%. Values of lambda k(3) for scan 1 and scan 2 were highly correlated (r(2) = 0.98; p < 0.0001; slope 0.955). Similarly, values of K-1 showed a significant correlation between scan 1 and scan 2 (r(2) = 0.61; e < 0.0001; slope 0.638) though the values for scan 2 were generally lower than those of scan 1, There was essentially no difference between the values of model constants calculated using the NLLSQ or LIN methods, Regional brain uptake of [C-11]L-deprenyl-D2 varied between scan 1 and scan 2, driven by the differences in arterial tracer input. Application of a 3-compartment model to regional time-activity data and arterial input function yielded lambda k(3) values for scan 1 and scan 2 with an average difference of -2.84 +/- 7.07%. Linear regression applied to values of hk, from the LIN and NLLSR methods validated the use of the linear method for calculating hk,. NUCL MED BIOL 21;1:43-49, 2000. (C) 2000 Elsevier Science Inc. All rights reserved. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Logan, J (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. FU NINDS NIH HHS [NS 15380] NR 16 TC 23 Z9 23 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD JAN PY 2000 VL 27 IS 1 BP 43 EP 49 DI 10.1016/S0969-8051(99)00088-8 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 288NY UT WOS:000085570900005 PM 10755644 ER PT J AU Lin, WY Hsieh, JF Tsai, SC Yen, TC Wang, SJ Knapp, FF AF Lin, WY Hsieh, JF Tsai, SC Yen, TC Wang, SJ Knapp, FF TI A comprehensive study on the blockage of thyroid and gastric uptakes of Re-188-perrhenate in endovascular irradiation using liquid-tilled balloon to prevent restenosis SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE Re-188-perrhenate; intravascular irradiation; beta particle; restenosis; blockage; thyroid uptake; gastric uptake ID LOW-DOSE IRRADIATION; NEOINTIMAL PROLIFERATION; CORONARY ANGIOPLASTY; HYPERPLASIA; THERAPY; RE-188; PERCHLORATE; CATHETER; ARTERY; MODEL AB Re-188-perrhenate has been reported effective in preventing restenosis after percutaneous transluminal coronary angioplasty. However, if the balloon ruptures, Re-188-perrhenate is released into the circulation, causing high radiation dosing to the thyroid and stomach. In this study, we evaluated the effects of perchlorate or iodide given at different times and in different ways for blocking the uptake of Re-188-perrhenate in the thyroid glands and the stomach to find the best method to apply clinically to reduce the radiation dose in case of balloon rupture. Sodium perchlorate, sodium iodide, or potassium iodide was given orally or intravenously to rats before, during, and after the injection of Re-188-perrhenate. The rats were sacrificed and we calculated the concentration of Re-188,perrhenate in various organs to evaluate the preblocking, mixed formula, and postblocking effects of perchlorate or iodide. Our data showed that the preblocking method effectively reduced the uptake of Re-188-perrhenate in both the thyroid and the stomach. The mixed formula method also demonstrated good blocking effect. The postblocking method showed obvious depression of thyroid uptake of perrhenate but its blocking effect on the stomach was not satisfactory. NUCL Men BIOL 27;1:83-87, 2000. (C) 2000 Elsevier Science Inc. All rights reserved. C1 Taichung Vet Gen Hosp, Dept Nucl Med, Taichung, Taiwan. Chi Mei Fdn Hosp, Dept Nucl Med, Tainan, Taiwan. Dept Nucl Med, Changhua, Taiwan. Chang Gung Univ, Chang Gung Mem Hosp, Dept Nucl Med, Taipei Med Ctr, Taipei, Taiwan. Chang Gung Univ, Sch Med, Taipei, Taiwan. Oak Ridge Natl Lab, Nucl Med Grp, Oak Ridge, TN USA. RP Tsai, SC (reprint author), Show Chwan Mem Hosp, Dept Nucl Med, 542,Sect 1,Chungshan Rd, Changhua, Taiwan. NR 26 TC 17 Z9 18 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 2000 VL 27 IS 1 BP 83 EP 87 DI 10.1016/S0969-8051(99)00079-7 PG 5 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 288NY UT WOS:000085570900011 PM 10755650 ER PT B AU Hawkins, WL Thompson, JL Finnegan, DL AF Hawkins, WL Thompson, JL Finnegan, DL BE Hecker, SS Mason, CFV Kadyrzhanov, KK Kislitsin, SB TI Hydrogeological investigations and radionuclide migration in groundwater at the Nevada Test Site SO NUCLEAR PHYSICAL METHODS IN RADIOECOLOGICAL INVESTIGATIONS OF NUCLEAR TEST SITES SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Physical Methods in Radioecological Investigations of Nuclear Test Sites CY JUN 07-10, 1999 CL ALMATY, KAZAKHSTAN SP NATO, Los Alamos Natl Lab, Inst Nucl Phys, Republic Kazakhstan, Natl Nucl Ctr AB Although the United States stopped nuclear testing in 1992, in the preceding three decades more than 800 nuclear devices were detonated underground at the Nevada Test Site (NTS) in southern Nevada. The majority of the detonation points of those tests are located above the water table, primarily in alluvium and volcanic rocks. In the main testing areas, the water table is 450-700 m below the surface. Pre- and post-event geologic investigations were conducted for each test and longer-term studies are underway to assess the regional environmental impact. Studies now in progress have not identified any impact on the regional groundwater flow system from testing, bur local effects have been discovered. In some areas where several tests have been conducted below the water table, flow-through and straddle-packer testing have revealed unexpectedly high hydraulic pressures at depth. The movement of radionuclides underground in the vicinity (similar to1 km) of individual test locations has been studied and has identified several mechanisms for this movement. One mechanism is prompt (within one second) injection of volatilised radioactive material through explosion-produced fractures and may transport some refractory elements as well. A second mechanism is gas pumping through pre-existing or explosion fractures. Only gases or easily volatilised elements are involved, and this process ceases within a few minutes when temperatures and pressures reduce toward normal values. (Of course, gaseous elements may continue to diffuse through the geologic media.) A third mechanism is movement with groundwater. Radionuclides that dissolve in water will be transported away from the test location driven by the hydraulic gradients. Radionuclides that are insoluble in water may move also if they form colloids or can sorb on naturally occurring colloids. At the NTS fracture, injection over distances of a few hundred meters has been observed. Gas pumping normally moves volatile radionuclides a few tens of meters from the nuclear test cavity. There are no known bounds on how far nonsorbing species such as tritium las tritiated water) or dissolved krypton can move with groundwater. Movement of plutonium and americium has been observed over distances of a kilometer, but the mechanism by which this movement occurred has not yet been determined. C1 Univ Calif Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. RP Hawkins, WL (reprint author), Univ Calif Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. NR 16 TC 0 Z9 0 U1 1 U2 5 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6447-3 J9 NATO SCI S 1 DISARM PY 2000 VL 31 BP 61 EP 74 PG 14 WC Chemistry, Inorganic & Nuclear; Environmental Sciences; Nuclear Science & Technology; Physics, Nuclear; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Environmental Sciences & Ecology; Nuclear Science & Technology; Physics; Radiology, Nuclear Medicine & Medical Imaging GA BR43U UT WOS:000166420000005 ER PT B AU Mason, CFV Lu, N Conca, J AF Mason, CFV Lu, N Conca, J BE Hecker, SS Mason, CFV Kadyrzhanov, KK Kislitsin, SB TI Radioactive strontium- and caesium-contaminated sites: Characterisation, transport, and remedial options SO NUCLEAR PHYSICAL METHODS IN RADIOECOLOGICAL INVESTIGATIONS OF NUCLEAR TEST SITES SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Physical Methods in Radioecological Investigations of Nuclear Test Sites CY JUN 07-10, 1999 CL ALMATY, KAZAKHSTAN SP NATO, Los Alamos Natl Lab, Inst Nucl Phys, Republic Kazakhstan, Natl Nucl Ctr AB Radioactive strontium (Sr) and radioactive caesium (Cs) are contaminants causing major concern because of their ease of entry into biological systems due to their similarity to calcium and potassium, respectively. As a result of the Chernobyl accident in 1986, large areas of the Ukraine are contaminated with these radionuclides. Areas both at the Los Alamos National Laboratory (LANL) in the United States and at the Semipalatinsk Test Site in Kazakhstan are also contaminated with these radionuclides. Both caesium and strontium are soluble in water, but their mobility in natural environments is retarded by their strong interactions with soil organic materials, clay minerals, and iron oxides. In this paper we examine a site at LANL contaminated with Cs-137 and Sr-90. Experimental results show that the distribution coefficients for Cs are much greater than those for Sr. This difference results in much faster dispersal of Sr through water-borne transport pathways. Furthermore, Sr is transported by sorption onto colloids, thereby providing an additional transport mechanism. Remedial options for contaminated sites require detailed studies of sorption processes of the local soils. Apart from the drastic measure of removing contaminated soils to a controlled area, the movement of contaminants can be controlled by the presence of media that will prevent both particulate movement and also immobilise soluble species. Immobilisation occurs through precipitation, sorption, and ion exchangers. C1 Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. RP Mason, CFV (reprint author), Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. NR 17 TC 1 Z9 1 U1 1 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6447-3 J9 NATO SCI S 1 DISARM PY 2000 VL 31 BP 89 EP 97 PG 9 WC Chemistry, Inorganic & Nuclear; Environmental Sciences; Nuclear Science & Technology; Physics, Nuclear; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Environmental Sciences & Ecology; Nuclear Science & Technology; Physics; Radiology, Nuclear Medicine & Medical Imaging GA BR43U UT WOS:000166420000007 ER PT B AU Efurd, DW Roensch, FR Inkret, WCT Hameedi, MJ Mason, CFV AF Efurd, DW Roensch, FR Inkret, WCT Hameedi, MJ Mason, CFV BE Hecker, SS Mason, CFV Kadyrzhanov, KK Kislitsin, SB TI Evaluation of the anthropogenic radionuclide concentrations in sediments and fauna collected in the arctic SO NUCLEAR PHYSICAL METHODS IN RADIOECOLOGICAL INVESTIGATIONS OF NUCLEAR TEST SITES SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Physical Methods in Radioecological Investigations of Nuclear Test Sites CY JUN 07-10, 1999 CL ALMATY, KAZAKHSTAN SP NATO, Los Alamos Natl Lab, Inst Nucl Phys, Republic Kazakhstan, Natl Nucl Ctr AB This study was performed to establish a quality controlled data set about the levels of anthropogenic radionuclide activity in the environment and in selected biota in the Arctic. Between 1993 and 1997 sediment and marine and terrestrial biota samples were collected in Alaska and in the surrounding waters, These samples were analysed at Los Alamos National Laboratory to identify the presence of the anthropogenic radionuclides, Sr-90,Cs-137, (238)pU, Pu239+240, and Am-241. One goal of this study was to determine the amounts and origins of anthropogenic radionuclides present in sediments. The anthropogenic radionuclide content of the sediments was predominantly the result of deposition of global fallout from nuclear explosions. No other sources of anthropogenic radionuclides could be conclusively identified. Biota samples of subsistence and ecological value were analysed for evidence of bioaccumulation of radionuclides. The measurements were combined with food consumption rates based on survey results for populations residing in three north Alaskan communities and on published, age-dependent ingestion coefficients. This action was carried out to estimate the potential radiological impacts from the consumption of traditional animal foods harvested in this region. No plutonium or americium was detected in any of the fauna samples. The results of this study indicate that the committed equivalent doses to adults from Sr-90 and Cs-137 owing to consumption of traditional food sources are consistent with currently accepted estimates of average doses received by adults in North America from atmospheric nuclear weapons testing fallout. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Efurd, DW (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6447-3 J9 NATO SCI S 1 DISARM PY 2000 VL 31 BP 99 EP 107 PG 9 WC Chemistry, Inorganic & Nuclear; Environmental Sciences; Nuclear Science & Technology; Physics, Nuclear; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Environmental Sciences & Ecology; Nuclear Science & Technology; Physics; Radiology, Nuclear Medicine & Medical Imaging GA BR43U UT WOS:000166420000008 ER PT B AU Henderson, RW Smale, RF AF Henderson, RW Smale, RF BE Hecker, SS Mason, CFV Kadyrzhanov, KK Kislitsin, SB TI External exposure estimates for individuals near the Nevada Test Site SO NUCLEAR PHYSICAL METHODS IN RADIOECOLOGICAL INVESTIGATIONS OF NUCLEAR TEST SITES SE NATO ADVANCED SCIENCE INSTITUTE SERIES, SUB-SERIES 1: DISARMAMENT TECHNOLOGIES LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Nuclear Physical Methods in Radioecological Investigations of Nuclear Test Sites CY JUN 07-10, 1999 CL ALMATY, KAZAKHSTAN SP NATO, Los Alamos Natl Lab, Inst Nucl Phys, Republic Kazakhstan, Natl Nucl Ctr AB Individuals living near the Nevada Test Site were exposed to both beta and gamma radiations from fission products and activation products resulting from the atmospheric testing of nuclear devices. These exposures, and the resultant doses were functions of the amount of material deposited, the time of arrival of the debris, and the amount of shielding afforded by structures. Results are presented for each of nine generic life-styles. These are representative of the living patterns of people residing in the area. For each event at each location for which data exist, a representative of each life-style was closely followed for 30 d. The results of these detailed calculations were then extrapolated to the present, employing a stochastic model. Results displayed are the geometric means and standard deviations derived from 25 independent determinations of the various quantities shown. For each determination, required parameters were randomly selected from appropriate distributions. Calculations yielded estimates for: 1) whole-body and skin dose due to gamma rays from material on the ground: 2) skin dose due to beta particles from material deposited directly on the skin; and 3) skin dose due to beta particles from material deposited on the ground. Organ dose estimates were established from the whole-body dose using appropriate conversion factors. For the homemaker life-style, the uterus dose was also calculated as a function of time for 9 mo. This assisted in estimating fetal dose as a function of gestation. C1 Univ Calif Los Alamos Natl Lab, Environm Safety & Hlth Div, Los Alamos, NM 87545 USA. RP Henderson, RW (reprint author), Univ Calif Los Alamos Natl Lab, Environm Safety & Hlth Div, POB 1663, Los Alamos, NM 87545 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6447-3 J9 NATO SCI S 1 DISARM PY 2000 VL 31 BP 191 EP 202 PG 12 WC Chemistry, Inorganic & Nuclear; Environmental Sciences; Nuclear Science & Technology; Physics, Nuclear; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Environmental Sciences & Ecology; Nuclear Science & Technology; Physics; Radiology, Nuclear Medicine & Medical Imaging GA BR43U UT WOS:000166420000017 ER PT S AU Roser, T AF Roser, T BE Meyer, HO Schwandt, P TI Acceleration and storage of polarized proton beam at RHIC SO NUCLEAR PHYSICS AT STORAGE RINGS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 4th International Conference on Nuclear Physics at Storage Rings (STORI99) CY SEP 12-16, 1999 CL INDIANA UNIV, BLOOMINGTON, IN SP Indiana Univ Cooler Facil, US Natl Sci Fdn, Indiana Univ Cyclotron Facil, Indiana Univ, Off Int Programs HO INDIANA UNIV AB High energy polarized beam collisions will open up the unique physics opportunities of studying spin effects in hard processes. However, the acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian Snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian Snakes and polarimeters are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible. Spin rotators around two RHIC interaction regions will allow for the collision of longitudinally polarized protons at the STAR and PHENIX detectors. C1 Brookhaven Natl Lab, AGS Dept, Upton, NY 11973 USA. RP Roser, T (reprint author), Brookhaven Natl Lab, AGS Dept, Upton, NY 11973 USA. NR 16 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 1-56396-928-9 J9 AIP CONF PROC PY 2000 VL 512 BP 213 EP 223 PG 11 WC Physics, Nuclear SC Physics GA BQ38Z UT WOS:000088226500024 ER PT J AU Brantley, PS Larsen, EW AF Brantley, PS Larsen, EW TI The simplified P-3 approximation SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID PRESSURIZED-WATER REACTORS; EQUATIONS AB The simplified P-3 (SP3) approximation to the multigroup neutron transport equation in arbitrary geometries is derived using a variational analysis. This derivation yields the SP3 equations along with material interface and Marshak-like boundary conditions. The multigroup SP3 approximation is reformulated as a system of within-group problems that can be solved iteratively. An "explicit" iterative algorithm for solving the within-group problem is described, Fourier analyzed and shown to be more efficient than the traditional FLIP implicit algorithm. Numerical results compare diffusion (P-1), simplified P-2 (SP2), and simplified P-3 calculations of a mixed-oxide (MOX) fuel benchmark problem to a reference transport calculation. The SP3 approximation can eliminate much of the inaccuracy in the diffusion and SP2 calculations of MOX fuel problems. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Michigan, Dept Nucl Engn & Radiol Sci, Ann Arbor, MI 48109 USA. RP Brantley, PS (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-23, Livermore, CA 94551 USA. NR 39 TC 67 Z9 68 U1 1 U2 4 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 2000 VL 134 IS 1 BP 1 EP 21 PG 21 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 267EW UT WOS:000084345200001 ER PT J AU Loaiza, DJ Haskin, EE AF Loaiza, DJ Haskin, EE TI Dominant delayed neutron precursors to model reactivity predictions for multiple fissioning nuclides SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID CONSTANTS AB The product of cumulative yield and probability of neutron emission is used to assess the relative importance of known delayed neutron precursors. Thirteen precursors are consistently dominant. Nonlinear fits to experimental delayed neutron decay data distinguish the decay constants of the three longest-lived dominant precursors: Br-87, I-137 and Br-88. Sensitivity calculations based on a six- to seven-group transformation lead to a proposed seven-group formulation in which the group decay constants are those of dominant precursors: Br-87, I-137, Br-88, Rb-93, I-139 Br-91 and Rb-96. An alternative six-group formulation is obtained by using the mean of the I-137 and Br-88 decay constants for group 2. The use of the suggested dominant precursor decay constants improves the goodness of fit To experimental data compared to that obtained from nonlinear least squares in which both group yields and decay constants are determined empirically. Reactivity worth and transient analyses confirm that the positive reactivity scale is preserved in the transformation. A known bias in the negative reactivity scale is eliminated by forcing the half-life of the longest-lived group to be the 55.9-s half-life of B-87, The proposed use of dominant precursor decay constants offers significant simplifications in data analysis and the analysis of fast, epithermal, and thermal reactors with multiple fissioning nuclides. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ New Mexico, Farris Engn Ctr 209, Albuquerque, NM 87131 USA. RP Loaiza, DJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS 1562, Los Alamos, NM 87545 USA. NR 16 TC 7 Z9 7 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 2000 VL 134 IS 1 BP 22 EP 36 PG 15 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 267EW UT WOS:000084345200002 ER PT J AU Jammes, C Hwang, RN AF Jammes, C Hwang, RN TI Conversion of single- and multilevel Breit-Wigner resonance parameters to pole representation parameters SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article AB One reliable and convenient way of processing the cross sections in the resolved energy region is by use of the generalized pole representation, whereby the Doppler-broadening calculation can be carried out rigorously using the analytical approach. So far, its applications have been limited to cases with resonance parameters specified by the Reich-Moore formalism. Although such an approach call in principle be extended to all three remaining representations of resolved resonance parameters specified by the ENDF data format, there is no computational tool for handling such a task at present. Given that Breit-Wigner formalisms are probably the most widely used by any evaluated nuclear data library to represent cross sections, a special effort needs to be made to convert the single- and multilevel Breit-Wigner resonance parameters to pole parameters. The FORTRAN computer code BW2PR has been developed for this purpose. Extensive calculations have been performed to demonstrate that the proposed method ensures the conservation of the information contained originally in Breit-Wigner resonance parameters. This will make it possible to apply the exact Doppler-broadening method to a larger collection of nuclides. C1 Argonne Natl Lab, Reactor Anal Div, Argonne, IL 60439 USA. RP Jammes, C (reprint author), Argonne Natl Lab, Reactor Anal Div, Argonne, IL 60439 USA. RI Jammes, Christian/H-3245-2013 OI Jammes, Christian/0000-0002-5970-7719 NR 18 TC 3 Z9 3 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD JAN PY 2000 VL 134 IS 1 BP 37 EP 49 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 267EW UT WOS:000084345200003 ER PT J AU Grimes, SM Anderson, JD Bauer, RW Madsen, VA AF Grimes, SM Anderson, JD Bauer, RW Madsen, VA TI Dependence of neutron total cross sections on energy for 100 <= E-n <= 500 MeV and mass number for 7 <= A <= 238 SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID SIMPLE RAMSAUER MODEL AB Two recent measurement programs have yielded an extensive body of neutron total cross-section data for a number of targets at energies up to 500 MeV. Recently, it has been shown that the simple Ramsauer model provides a good description of the data up to 120 MeV. The parameterization developed in this energy region did not do as well above this energy. The data in the region 100 less than or equal to E-n less than or equal to 500 MeV are examined and it is concluded that a simple parameterization can describe the data well. The applicability of the Glauber model is tested in the energy region above 150 MeV. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Ohio State Univ, Dept Phys, Athens, OH 45701 USA. Oregon State Univ, Dept Phys, Corvallis, OR 97331 USA. RP Grimes, SM (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 11 TC 8 Z9 8 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 2000 VL 134 IS 1 BP 77 EP 88 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 267EW UT WOS:000084345200006 ER PT J AU Meeks, MK Baker, MC Bonazza, R AF Meeks, MK Baker, MC Bonazza, R TI Suppression of vapor explosions in a water-molten-tin system by augmentation of the void fraction SO NUCLEAR TECHNOLOGY LA English DT Article DE fuel-coolant interactions; imaging of molten metals; X-ray imaging ID MELTS AB Experiments were performed to determine the likelihood of a vapor explosion when injecting an inert gas (nitrogen) and a coolant (water) into a pool of molten metal (tin) in a large-scale chamber (similar to 20 kg fuel). The injection flow rates of the water and nitrogen gas were the principal experimental variables, with average water flow rates up to 0.05 x 10(-3) m(3)/s and gas flow rates ranging from 0.33 x 10(-3) to 1.67 x 10(-3) m(3)/s. Of 35 successful experiments, 11 resulted in art explosive interaction, as determined by audible signals, videotape, and accelerometer data. The main objective of the investigation was to determine the existence of a boundary between explosive and nonexplosive regions in the water-gas flow rate plane: Such a boundary was indeed identified and approximated by a straight line. Two experiments in which explosive interactions were obtained in the low water/gas flow regions after a relatively long time of coolant injection (similar to 5 to 10 s) demonstrate the hitherto undervalued importance of the temporal variable. C1 Univ Wisconsin, Dept Engn Phys, Madison, WI 53706 USA. Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Meeks, MK (reprint author), Univ Wisconsin, Dept Engn Phys, 1500 Engn Dr, Madison, WI 53706 USA. NR 26 TC 3 Z9 3 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD JAN PY 2000 VL 129 IS 1 BP 69 EP 81 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 267ZR UT WOS:000084389600006 ER PT S AU McGraw, R Schaaf, P Reiss, H AF McGraw, R Schaaf, P Reiss, H BE Hale, BN Kulmala, M TI An application of the Kubo and Nyquist relations to nucleation SO NUCLEATION AND ATMOSPHERIC AEROSOLS 2000 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Conference on Nucleation and Atmospheric Aerosols (ICNAA) CY AUG 06-11, 2000 CL UNIV MISSOURI ROLLA, ROLLA, MO SP Int Assoc Metrol & Atmospher Sci, Int Commiss Clouds & Precipitat, Comm Nucleat & Atmospher Aerosols, World Meteorol Org, Cloud & Aerosols Sci Lab, Natl Sci Fdn, Univ Missouri Rolla Phys Dept HO UNIV MISSOURI ROLLA ID GAS-LIQUID NUCLEATION; LENNARD-JONES SYSTEM; MOLECULAR THEORY; VAPOR AB We examine fluctuations in cluster evaporation and growth and express these, using the Nyquist and Kubo relations [1,2], in terms of the resistance to single-cluster motion along the coordinate of cluster size. If successful in future development, the methods introduced here will have application to the abstraction of nucleation rates from computer simulations of individual cluster evaporation/growth events. C1 Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. RP McGraw, R (reprint author), Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 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 1-56396-958-0 J9 AIP CONF PROC PY 2000 VL 534 BP 3 EP 6 PG 4 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics, Atomic, Molecular & Chemical SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics GA BQ78Z UT WOS:000089526000001 ER PT S AU Mikheev, VB Laulainen, NS Barlow, SE AF Mikheev, VB Laulainen, NS Barlow, SE BE Hale, BN Kulmala, M TI Experimental nucleation studies with a Laminar Flow Tube Reactor SO NUCLEATION AND ATMOSPHERIC AEROSOLS 2000 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Conference on Nucleation and Atmospheric Aerosols (ICNAA) CY AUG 06-11, 2000 CL UNIV MISSOURI ROLLA, ROLLA, MO SP Int Assoc Metrol & Atmospher Sci, Int Commiss Clouds & Precipitat, Comm Nucleat & Atmospher Aerosols, World Meteorol Org, Cloud & Aerosols Sci Lab, Natl Sci Fdn, Univ Missouri Rolla Phys Dept HO UNIV MISSOURI ROLLA ID HOMOGENEOUS NUCLEATION AB A Laminar Flow Tube Reactor (LFTR) has been used as a quantitative tool for nucleation measurements. It has been specially designed and constructed in order to minimize the potential experimental inaccuracies. Careful attention has been paid to the temperature conditions inside the LFTR. Other sources of experimental uncertainties, such as initial vapor concentration conditions, calculations of the parameters of the nucleation zone, and particle concentration measurements have been thoroughly analyzed as well. The nucleation rate dependence as a function of supersaturation and temperature has been measured for the dibutyl phthalate, ethylene glycol, and glycerol. The experimental results have been compared with the other experimental data and with the theoretical predictions. C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Mikheev, VB (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, POB 999, Richland, WA 99352 USA. NR 7 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 1-56396-958-0 J9 AIP CONF PROC PY 2000 VL 534 BP 55 EP 58 PG 4 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics, Atomic, Molecular & Chemical SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics GA BQ78Z UT WOS:000089526000014 ER PT S AU Mikheev, VB Laulainen, NS Pervukhin, VV Barlow, SE AF Mikheev, VB Laulainen, NS Pervukhin, VV Barlow, SE BE Hale, BN Kulmala, M TI Laminar Flow Tube Reactor interface with quadrupole mass spectrometer SO NUCLEATION AND ATMOSPHERIC AEROSOLS 2000 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Conference on Nucleation and Atmospheric Aerosols (ICNAA) CY AUG 06-11, 2000 CL UNIV MISSOURI ROLLA, ROLLA, MO SP Int Assoc Metrol & Atmospher Sci, Int Commiss Clouds & Precipitat, Comm Nucleat & Atmospher Aerosols, World Meteorol Org, Cloud & Aerosols Sci Lab, Natl Sci Fdn, Univ Missouri Rolla Phys Dept HO UNIV MISSOURI ROLLA AB Nucleation of supersaturated water vapor was studied using the Laminar Flow Tube Reactor (LFTR) technique. In order to check the presence of contaminants in the freshly nucleated water particles, the LFTR has been connected to a mass spectrometer. Trace amounts contaminants arising from the substances used as a circulating liquid to maintain temperatures of the LFTR have been detected. The results of the mass spectroscopic analysis are in full agreement with the observed values of nucleation rate. C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Mikheev, VB (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, POB 999, Richland, WA 99352 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-958-0 J9 AIP CONF PROC PY 2000 VL 534 BP 71 EP 74 PG 4 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics, Atomic, Molecular & Chemical SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics GA BQ78Z UT WOS:000089526000018 ER PT S AU Kathmann, SM Schenter, GK Garrett, BC AF Kathmann, SM Schenter, GK Garrett, BC BE Hale, BN Kulmala, M TI Dynamical nucleation theory SO NUCLEATION AND ATMOSPHERIC AEROSOLS 2000 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Conference on Nucleation and Atmospheric Aerosols (ICNAA) CY AUG 06-11, 2000 CL UNIV MISSOURI ROLLA, ROLLA, MO SP Int Assoc Metrol & Atmospher Sci, Int Commiss Clouds & Precipitat, Comm Nucleat & Atmospher Aerosols, World Meteorol Org, Cloud & Aerosols Sci Lab, Natl Sci Fdn, Univ Missouri Rolla Phys Dept HO UNIV MISSOURI ROLLA ID WATER CLUSTERS; LIQUID AB The nucleation rate is governed by the corresponding evaporation and condensation rate constants for the multi-step kinetics for populations of individual clusters. In our recent publications on Dynamical Nucleation Theory (DNT) a formalism was presented which allows the evaporation and condensation rate constants to be determined directly. Given these rate constants the transient and steady state behavior of the nucleation rate can be investigated by solving the pseudo-first order kinetic equations. The use of variational transition state theory to estimate the monomer evaporation rate constant provides a unique and physically consistent value for the cluster constraining volume. Application of DNT to small polarizable water clusters and future work on multi-component systems will be discussed. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Kathmann, SM (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Garrett, Bruce/F-8516-2011; Schenter, Gregory/I-7655-2014 OI Schenter, Gregory/0000-0001-5444-5484 NR 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 1-56396-958-0 J9 AIP CONF PROC PY 2000 VL 534 BP 197 EP 200 PG 4 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics, Atomic, Molecular & Chemical SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics GA BQ78Z UT WOS:000089526000047 ER PT S AU Garrett, BC Kathmann, SM Schenter, GK AF Garrett, BC Kathmann, SM Schenter, GK BE Hale, BN Kulmala, M TI Kinetics of cluster evaporation and condensation important in homogeneous vapor phase nucleation SO NUCLEATION AND ATMOSPHERIC AEROSOLS 2000 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Conference on Nucleation and Atmospheric Aerosols (ICNAA) CY AUG 06-11, 2000 CL UNIV MISSOURI ROLLA, ROLLA, MO SP Int Assoc Metrol & Atmospher Sci, Int Commiss Clouds & Precipitat, Comm Nucleat & Atmospher Aerosols, World Meteorol Org, Cloud & Aerosols Sci Lab, Natl Sci Fdn, Univ Missouri Rolla Phys Dept HO UNIV MISSOURI ROLLA ID TRANSITION-STATE THEORY AB Variational transition state theory (VTST) is used to estimate rate constants for the processes of evaporation and condensation that are important in homogeneous vapor-phase nucleation. We review the approximations inherent in the calculations of the rate constants, and indicate how VTST provides a framework in which systematic improvements to the approximations can be made. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Garrett, BC (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Garrett, Bruce/F-8516-2011; Schenter, Gregory/I-7655-2014 OI Schenter, Gregory/0000-0001-5444-5484 NR 11 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 1-56396-958-0 J9 AIP CONF PROC PY 2000 VL 534 BP 201 EP 204 PG 4 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics, Atomic, Molecular & Chemical SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics GA BQ78Z UT WOS:000089526000048 ER PT S AU McGraw, R AF McGraw, R BE Hale, BN Kulmala, M TI Scaling properties of critical nuclei and nucleation rate SO NUCLEATION AND ATMOSPHERIC AEROSOLS 2000 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Conference on Nucleation and Atmospheric Aerosols (ICNAA) CY AUG 06-11, 2000 CL UNIV MISSOURI ROLLA, ROLLA, MO SP Int Assoc Metrol & Atmospher Sci, Int Commiss Clouds & Precipitat, Comm Nucleat & Atmospher Aerosols, World Meteorol Org, Cloud & Aerosols Sci Lab, Natl Sci Fdn, Univ Missouri Rolla Phys Dept HO UNIV MISSOURI ROLLA ID GAS-LIQUID NUCLEATION; CORRESPONDING STATES CORRELATION; HOMOGENEOUS NUCLEATION; FREE-ENERGY; VAPOR; SIZE; EXPANSION; CLUSTERS; WORK AB Scaling approaches to nucleation are reviewed first for molecular properties of the critical nucleus and then for the nucleation rate. Scaling properties of critical nuclei are based on the Kelvin relation. These are reexamined in light of more recent density functional and molecular dynamics calculations. For the nucleation rate scaling we derive thermodynamic phase space paths of constant reduced nucleation barrier height, W*/kT. These paths, expressed in terms of the conjugate variables T and lnS, where T is temperature and S is saturation ratio, approximate conditions at the nucleation threshold and contours of constant nucleation rate. Finally we show that both scaling approaches (molecular and rate) are fundamentally connected through nucleation theorems and may therefore be combined. The combination of Kelvin-based molecular scaling and scaled nucleation theory for the rate is derived and shown to give a temperature dependence that is in agreement with experiment. C1 Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. RP McGraw, R (reprint author), Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. NR 26 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 1-56396-958-0 J9 AIP CONF PROC PY 2000 VL 534 BP 373 EP 385 PG 5 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics, Atomic, Molecular & Chemical SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics GA BQ78Z UT WOS:000089526000091 ER PT S AU Onasch, TB McGraw, R Prenni, AJ Tolbert, MA Imre, A AF Onasch, TB McGraw, R Prenni, AJ Tolbert, MA Imre, A BE Hale, BN Kulmala, M TI Efflorescence and ice nucleation in ammonium sulfate particles: Analysis of experimental results using scaled nucleation theory SO NUCLEATION AND ATMOSPHERIC AEROSOLS 2000 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Conference on Nucleation and Atmospheric Aerosols (ICNAA) CY AUG 06-11, 2000 CL UNIV MISSOURI ROLLA, ROLLA, MO SP Int Assoc Metrol & Atmospher Sci, Int Commiss Clouds & Precipitat, Comm Nucleat & Atmospher Aerosols, World Meteorol Org, Cloud & Aerosols Sci Lab, Natl Sci Fdn, Univ Missouri Rolla Phys Dept HO UNIV MISSOURI ROLLA ID DELIQUESCENCE; TEMPERATURE AB Temperature-dependent efflorescence and ice nucleation results of ammonium sulfate aerosol obtained from flow tube studies are analyzed using a newly developed model based on scaled nucleation theory. The presented thermodynamic model defines trajectories of constant reduced nucleation barrier height as a function of temperature and yields simple analytic expressions for the liquid-solid nucleation boundaries. Within the context of the model the experimental results are interpreted in terms of surface enthalpy, entropy and nucleus size. These thermodynamic properties, along with a full thermodynamic model, can be then used to predict changes in the composition and phase of ammonium sulfate particles over the wide range of relative humidity and temperature conditions found in the atmosphere. C1 Brookhaven Natl Lab, Div Atmospher Sci, Dept Environm Sci, Upton, NY 11973 USA. RP Onasch, TB (reprint author), Brookhaven Natl Lab, Div Atmospher Sci, Dept Environm Sci, Upton, NY 11973 USA. RI Prenni, Anthony/A-6820-2011 NR 11 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 1-56396-958-0 J9 AIP CONF PROC PY 2000 VL 534 BP 428 EP 431 PG 2 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics, Atomic, Molecular & Chemical SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics GA BQ78Z UT WOS:000089526000101 ER PT S AU Laulainen, N Ghan, S Easter, R Zaveri, R AF Laulainen, N Ghan, S Easter, R Zaveri, R BE Hale, BN Kulmala, M TI Comparison of simulated and observed aerosol optical depth SO NUCLEATION AND ATMOSPHERIC AEROSOLS 2000 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Conference on Nucleation and Atmospheric Aerosols (ICNAA) CY AUG 06-11, 2000 CL UNIV MISSOURI ROLLA, ROLLA, MO SP Int Assoc Metrol & Atmospher Sci, Int Commiss Clouds & Precipitat, Comm Nucleat & Atmospher Aerosols, World Meteorol Org, Cloud & Aerosols Sci Lab, Natl Sci Fdn, Univ Missouri Rolla Phys Dept HO UNIV MISSOURI ROLLA AB A variety of measurements have been used to evaluate the treatment of aerosol radiative properties and radiative impacts of aerosols simulated by the Model for Integrated Research on Atmospheric Global Exchanges (MIRAGE). This paper focuses on comparisons of simulated and measured aerosol optical depth (AOD). When the analyzed relative humidity is used to calculate aerosol water uptake in MIRAGE, the simulated AOD agrees with most surface measurements after cloudy conditions are filtered out and differences between model and station elevations are accounted for. Simulated AODs are low over sites in Brazil during the biomass burning season and over sites in central Canada during the wildfire season, which can be attributed to limitations in the organic and black carbon emissions data used by MIRAGE. The simulated AODs are mostly within a factor of two of satellite estimates, but MIRAGE simulates excessively high AODs off the east coast of the US and China, and too little dust off the coast of West Africa and in the Arabian Sea. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Laulainen, N (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Ghan, Steven/H-4301-2011; OI Ghan, Steven/0000-0001-8355-8699; Zaveri, Rahul/0000-0001-9874-8807 NR 4 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 1-56396-958-0 J9 AIP CONF PROC PY 2000 VL 534 BP 573 EP 576 PG 4 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics, Atomic, Molecular & Chemical SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics GA BQ78Z UT WOS:000089526000134 ER PT S AU McGraw, R Wright, DL Benkovitz, CM Schwartz, SE AF McGraw, R Wright, DL Benkovitz, CM Schwartz, SE BE Hale, BN Kulmala, M TI From aerosol microphysics to geophysics using the method of moments SO NUCLEATION AND ATMOSPHERIC AEROSOLS 2000 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 15th International Conference on Nucleation and Atmospheric Aerosols (ICNAA) CY AUG 06-11, 2000 CL UNIV MISSOURI ROLLA, ROLLA, MO SP Int Assoc Metrol & Atmospher Sci, Int Commiss Clouds & Precipitat, Comm Nucleat & Atmospher Aerosols, World Meteorol Org, Cloud & Aerosols Sci Lab, Natl Sci Fdn, Univ Missouri Rolla Phys Dept HO UNIV MISSOURI ROLLA ID DYNAMICS AB We describe new developments in the application of the Quadrature Method of Moments (QMOM) [1]. These include the first application of the QMOM in a 3-D chemical transformation and transport model on the sub-hemispheric scale [2]. The QMOM simultaneously tracks an arbitrary (even) number of moments of a particle size distribution directly in space and time without the need for explicitly representing the distribution itself. The present implementation evolves the six lowest-order radial moments for each of several externally-mixed aerosol populations. From these moments we report modeled geographic distributions of several aerosol properties, including a shortwave radiative forcing obtained using the Multiple Isomomental Distribution Aerosol Surrogate (MIDAS) technique [3]. These results demonstrate the capabilities of these moment-based techniques to simultaneously represent aerosol nucleation, condensation, coagulation, dry deposition, wet removal, cloud activation, and transport processes in a large-scale model, and to yield aerosol optical properties and radiative influence from the modeled aerosol moments. We report on recent extensions of the method for simulation of internal mixtures and generally-mixed aerosols, and on a bivariate extension of the QMOM for modeling simultaneous coagulation and sintering of particle populations [4]. C1 Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. RP McGraw, R (reprint author), Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. RI Schwartz, Stephen/C-2729-2008 OI Schwartz, Stephen/0000-0001-6288-310X 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 1-56396-958-0 J9 AIP CONF PROC PY 2000 VL 534 BP 785 EP 788 PG 4 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics, Atomic, Molecular & Chemical SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Physics GA BQ78Z UT WOS:000089526000179 ER PT S AU Miller, MK AF Miller, MK BE Gonis, A Turchi, PEA Ardell, AJ TI Characterization of the early stages of phase separation by atom probe tomography SO NUCLEATION AND GROWTH PROCESSES IN MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nucleation and Growth Processes in Materials held at the 1999 MRS Fall Meeting CY NOV 29-DEC 01, 1999 CL BOSTON, MA SP Mat Res Soc, Lawrence Livermore Natl Lab AB An atom probe tomography characterization of the early stages of phase separation in the Fe-Cu-Ni system has been performed. The development of the copper-enriched regions into copper precipitates has been investigated during isothermal ageing at 573 K and 673 K for times up to 10,000 h. The formation and growth of the secondary precipitates in the nickel based superalloy, Alloy 718, have been determined during isothermal ageing at 873 K. These secondary precipitates were found to be a mixture of the L1(2)-ordered gamma' phase and the DO22-ordered gamma " phase. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Miller, MK (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 9 TC 4 Z9 4 U1 0 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-488-2 J9 MATER RES SOC SYMP P PY 2000 VL 580 BP 35 EP 40 PG 6 WC Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BR05A UT WOS:000165506200005 ER PT S AU Misra, A Verdier, M Mahan, JE Mitchell, TE AF Misra, A Verdier, M Mahan, JE Mitchell, TE BE Gonis, A Turchi, PEA Ardell, AJ TI Characterization of epitaxial growth of semiconducting rhenium "disilicide" films SO NUCLEATION AND GROWTH PROCESSES IN MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nucleation and Growth Processes in Materials held at the 1999 MRS Fall Meeting CY NOV 29-DEC 01, 1999 CL BOSTON, MA SP Mat Res Soc, Lawrence Livermore Natl Lab ID VACANCY GENERATION; 001 SILICON; THIN-FILMS; RESI2 AB We have characterized, through transmission electron microscopy (TEM), the ReSi2-x thin films grown by reactive deposition on (001) Si. ReSi2-x thin films exhibit a distorted body-centered tetragonal MoSi2-type structure, and have excellent epitaxy on (001) Si since the face diagonal of the Si unit cell is equal to the c lattice parameter of silicide. The Si-deficient composition in the "disilicide" may be accommodated by collapse and shear of missing Si planes to form planar faults. Kirkendall voids are also observed at the film-substrate interface. The engineering of the defect and interface structures of these complex, non-stoichiometric silicides for optimized optoelectronic properties ale discussed. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Misra, A (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS G755, Los Alamos, NM 87545 USA. RI Misra, Amit/H-1087-2012 NR 22 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 1-55899-488-2 J9 MATER RES SOC SYMP P PY 2000 VL 580 BP 135 EP 140 PG 6 WC Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BR05A UT WOS:000165506200021 ER PT S AU Gabrisch, H Kjeldgaard, L Olesen, AV Johnson, E Dahmen, U AF Gabrisch, H Kjeldgaard, L Olesen, AV Johnson, E Dahmen, U BE Gonis, A Turchi, PEA Ardell, AJ TI Kinetic limitations to shape equilibration of liquid Pb inclusions in Al SO NUCLEATION AND GROWTH PROCESSES IN MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nucleation and Growth Processes in Materials held at the 1999 MRS Fall Meeting CY NOV 29-DEC 01, 1999 CL BOSTON, MA SP Mat Res Soc, Lawrence Livermore Natl Lab ID ALUMINUM AB The shape of liquid Pb inclusions in Al was investigated by in-situ electron microscopy over a temperature interval from 300 to 500 degreesC. The inclusion shape was found to depend on size and temperature. During isothermal annealing after melting, small inclusions rounded off while larger inclusions remained faceted until the temperature was raised to about 500 degreesC. During subsequent cooling, inclusions refaceted, although less strongly than during heating. The shape hysteresis between heating and cooling cycles was found to be due to the barrier of ledge nucleation necessary to advance the faceted interfaces. The observations show that the step energy depends on temperature and its disappearance at about 540-600 degreesC indicates a roughening transition. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Gabrisch, H (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, 1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Gabrisch, Heike/I-5021-2013 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 1-55899-488-2 J9 MATER RES SOC SYMP P PY 2000 VL 580 BP 257 EP 264 PG 8 WC Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BR05A UT WOS:000165506200039 ER PT S AU Jin, O Schwarz, RB Alamgir, FM Jain, H AF Jin, O Schwarz, RB Alamgir, FM Jain, H BE Gonis, A Turchi, PEA Ardell, AJ TI Optimizing the metalloid content in bulk metallic glasses SO NUCLEATION AND GROWTH PROCESSES IN MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nucleation and Growth Processes in Materials held at the 1999 MRS Fall Meeting CY NOV 29-DEC 01, 1999 CL BOSTON, MA SP Mat Res Soc, Lawrence Livermore Natl Lab ID ALLOYS AB We have studied the effect of phosphorus content on the formation and properties of bulk Pd-Cu-P and Pd-Ni-P metallic glasses. It was found that the molar volumes of the Pd-Ni-P bulk glasses plotted as a function of P content follow a straight line whereas those for the Pd-Cu-P glasses follow two straight lines of different slopes, intersecting at a critical P concentration. The transition in molar volume behavior is attributed to a change in the alloy's short-range order with increasing P content. The origin of this structural change is discussed based on x-ray photoelectron spectroscopy (XPS) measurements. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Jin, O (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. NR 8 TC 10 Z9 10 U1 1 U2 6 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-488-2 J9 MATER RES SOC SYMP P PY 2000 VL 580 BP 277 EP 282 PG 6 WC Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA BR05A UT WOS:000165506200042 ER PT J AU Overbeek, R Larsen, N Pusch, GD D'Souza, M Selkov, E Kyrpides, N Fonstein, M Maltsev, N Selkov, E AF Overbeek, R Larsen, N Pusch, GD D'Souza, M Selkov, E Kyrpides, N Fonstein, M Maltsev, N Selkov, E TI WIT: integrated system for high-throughput genome sequence analysis and metabolic reconstruction SO NUCLEIC ACIDS RESEARCH LA English DT Article ID METHANOCOCCUS-JANNASCHII AB The WIT (What Is There) (http://wit.mcs.anl.gov/WIT2/) system has been designed to support comparative analysis of sequenced genomes and to generate metabolic reconstructions based on chromosomal sequences and metabolic modules from the EMP/MPW family of databases. This system contains data derived from about 40 completed or nearly completed genomes. Sequence homologies, various ORF-clustering algorithms, relative gene positions on the chromosome and placement of gene products in metabolic pathways (metabolic reconstruction) can be used for the assignment of gene functions and for development of overviews of genomes within WIT. The integration of a large number of phylogenetically diverse genomes in WIT facilitates the understanding of the physiology of different organisms. C1 Integrated Genom Inc, Chicago, IL 60612 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Overbeek, R (reprint author), Integrated Genom Inc, 2201 W Campbell Pk Dr, Chicago, IL 60612 USA. RI Kyrpides, Nikos/A-6305-2014 OI Kyrpides, Nikos/0000-0002-6131-0462 NR 19 TC 231 Z9 243 U1 0 U2 1 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 2000 VL 28 IS 1 BP 123 EP 125 DI 10.1093/nar/28.1.123 PG 3 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 276UT UT WOS:000084896300033 PM 10592199 ER PT J AU Xenarios, I Rice, DW Salwinski, L Baron, MK Marcotte, EM Eisenberg, D AF Xenarios, I Rice, DW Salwinski, L Baron, MK Marcotte, EM Eisenberg, D TI DIP: the Database of Interacting Proteins SO NUCLEIC ACIDS RESEARCH LA English DT Article AB The Database of Interacting Proteins (DIP; http://dip.doe-mbi.ucla.edu) is a database that documents experimentally determined protein-protein interactions, This database is intended to provide the scientific community with a comprehensive and integrated tool for browsing and efficiently extracting information about protein interactions and interaction networks in biological processes, Beyond cataloging details of protein-protein interactions, the DIP is useful for understanding protein function and protein-protein relationships, studying the properties of networks of interacting proteins, benchmarking predictions of protein-protein interactions, and studying the evolution of protein-protein interactions. C1 Univ Calif Los Angeles, DOE Lab Struct Biol & Mol Med, Inst Mol Biol, Los Angeles, CA 90095 USA. RP Eisenberg, D (reprint author), Univ Calif Los Angeles, DOE Lab Struct Biol & Mol Med, Inst Mol Biol, POB 951570, Los Angeles, CA 90095 USA. OI Xenarios, Ioannis/0000-0002-3413-6841 NR 16 TC 459 Z9 484 U1 2 U2 10 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 2000 VL 28 IS 1 BP 289 EP 291 DI 10.1093/nar/28.1.289 PG 3 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 276UT UT WOS:000084896300083 PM 10592249 ER PT J AU Dralyuk, I Brudno, M Gelfand, MS Zorn, M Dubchak, I AF Dralyuk, I Brudno, M Gelfand, MS Zorn, M Dubchak, I TI ASDB: database of alternatively spliced genes SO NUCLEIC ACIDS RESEARCH LA English DT Article AB Version 2.1 of ASDB (Alternative Splicing Data Base) contains 1922 protein and 2486 DNA sequences. The protein entries from SWISS-PROT are joined into clusters corresponding to alternatively spliced variants of one gene. The DNA division consists of complete genes with alternative splicing mentioned or annotated in GenBank, The search engine allows one to search over SWISS-PROT and GenBank fields and then follow the links to all variants. The database can be assessed at the URL http://cbcg.nersc.gov/asdb. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Ctr, Berkeley, CA 94720 USA. NIIGenetika, State Sci Ctr Biotechnol, Moscow 113545, Russia. RP Dubchak, I (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Ctr, Berkeley, CA 94720 USA. RI Gelfand, Mikhail/F-3425-2012 NR 6 TC 38 Z9 41 U1 0 U2 3 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD JAN 1 PY 2000 VL 28 IS 1 BP 296 EP 297 DI 10.1093/nar/28.1.296 PG 2 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 276UT UT WOS:000084896300086 PM 10592252 ER PT J AU D'Souza, M Romine, MF Maltsev, N AF D'Souza, M Romine, MF Maltsev, N TI SENTRA, a database of signal transduction proteins SO NUCLEIC ACIDS RESEARCH LA English DT Article ID SEARCH AB SENTRA, available via URL http://wit.mcs.anl.gov/WIT2/Sentra/, is a database of proteins associated with,microbial signal transduction, The database currently includes the classical two-component signal transduction pathway proteins and methyl-accepting chemotaxis proteins, but will be expanded to also include other classes of signal transduction systems that are modulated by phosphorylation or methylation reactions. Although the majority of database-entries are from prokaryotic systems, eukaroytic proteins with bacterial-like signal transduction domains are also included. Currently SENTRA contains signal transduction proteins in 34 complete and almost completely sequenced prokaryotic genomes; as well as sequences from 243 organisms available in public databases (SWISS-PROT and EMBL). The analysis was carried out within the framework of the WIT2 system, which is designed and implemented to support genetic sequence analysis and comparative analysis of sequenced genomes. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Pacific NW Lab, Environm Microbiol Grp, Richland, WA 99352 USA. RP Maltsev, N (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 9 TC 6 Z9 6 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 2000 VL 28 IS 1 BP 335 EP 336 DI 10.1093/nar/28.1.335 PG 2 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 276UT UT WOS:000084896300100 PM 10592266 ER PT J AU de Almeida, VF Chapman, AM Derby, JJ AF de Almeida, VF Chapman, AM Derby, JJ TI On equilibration and sparse factorization of matrices arising in finite element solutions of partial differential equations SO NUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS LA English DT Article DE matrix equilibration; scaling; incomplete LU factorization; pivoting; preconditioning; sparse finite-element matrices; incompressible fluids; Navier-Stokes equations ID SYSTEMS AB Investigations of scaling and equilibration of general matrices have been traditionally aimed at the effects on the stability and accuracy of LU factorizations-the so-called scaling problem. Notably, Skeel (1979) concludes that no systematic scaling procedure can be concocted for general matrices exempt from the danger of disastrous effects. Other researchers suggest that scaling procedures are not beneficial and should be abandoned altogether. Stability and accuracy issues notwithstanding, we show that this unglamorous technique has a profound impact on the sparsity of the resulting LU factors. In the modern era of fast computing, equilibration can play a key role in constructing incomplete sparse factorizations to solve a problem unstably, but quickly and iteratively. This article presents practical evidence, on the basis of sparsity, that scaling is an indispensable companion for sparse factorization algorithms when applied to realistic problems of industrial interest. In light of our findings, we conclude that equilibration with the oo-norm is superior than equilibration with the 2-norm. (C) 2000 John Wiley & Sons, Inc. C1 Univ Minnesota, Dept Chem Engn & Mat Sci, Army High Performance Comp Res Ctr, Minneapolis, MN 55455 USA. Univ Minnesota, Minnesota Supercomp Inst, Minneapolis, MN 55455 USA. NEC Syst Inc, The Woodlands, TX 77381 USA. RP de Almeida, VF (reprint author), Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RI Derby, Jeffrey/B-9706-2009; de Almeida, Valmor/P-5498-2016; OI de Almeida, Valmor/0000-0003-0899-695X; Derby, Jeffrey/0000-0001-6418-2155 NR 33 TC 6 Z9 6 U1 2 U2 3 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0749-159X J9 NUMER METH PART D E JI Numer. Meth. Part Differ. Equ. PD JAN PY 2000 VL 16 IS 1 BP 11 EP 29 PG 19 WC Mathematics, Applied SC Mathematics GA 264FC UT WOS:000084169100002 ER PT J AU Hecht, MW Wingate, BA Kassis, P AF Hecht, Matthew W. Wingate, Beth A. Kassis, Patricia TI A better, more discriminating test problem for ocean tracer transport SO OCEAN MODELLING LA English DT Article AB Many test problems have been posed in which the behavior of schemes may be examined within the simplified context of passive tracer transport. Most often these tests involve transport of a tracer containing sharp or discontinuous gradients within a smooth advecting field. Hecht et al. [J. Geophys. Res. 100 (1995) 20763-20778] presented a test problem, using the simple analytical gyre of Stommel [Trans. Am. Geophys. Union 29 (1948) 202-206], in which an initially smooth tracer field is transported through a highly sheared circulation, representing another scenario of relevance to ocean modeling. We present a modification of that test in which the underlying grid is rotated relative to the gyre, such that the western boundary falls at 45 to the principal grid axes. The advection schemes used by most ocean modelers to date are examined within this test problem. We find, in two cases, that methods which performed acceptably under the original formulation of the problem, and which have seen extensive application to geophysical fluid dynamics, fail to perform acceptably within the reformulated problem. The important qualities of this more discriminating test include the skewing of the fast boundary current flow relative to the underlying grid axes and the high shear in that boundary current. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 [Hecht, Matthew W.] Natl Ctr Atmospher Res, Boulder, CO 80307 USA. [Wingate, Beth A.] Los Alamos Natl Lab, Los Alamos, NM USA. [Kassis, Patricia] Woods Hole Oceanog Inst, MIT WHOI Joint Program, Woods Hole, MA 02543 USA. RP Hecht, MW (reprint author), Natl Ctr Atmospher Res, POB 3000, Boulder, CO 80307 USA. EM hecht@ncar.ucar.edu; wingate@lanl.gov; bradshaw@darla.whoi.edu FU US Department of Energy (DOE) Office of Health and Environmental Research; Institute for Geophysics and Planetary Physics (IGPP) at Los Alamos National Laboratory; DOE; National Science Foundation FX Support for this work is gratefully acknowledged from a number of programmatic and institutional sources: the Global Change Distinguished Postdoctoral Fellowship program, sponsored by the US Department of Energy (DOE) Office of Health and Environmental Research (MH); the Institute for Geophysics and Planetary Physics (IGPP) at Los Alamos National Laboratory (MH, PK); the DOE Climate Change Prediction Program (MH, BW, PK) and the National Science Foundation (MH, BW) as the principal sponsor of NCAR. We also acknowledge P. Smolarkiewicz for many useful conversations regarding advection, T. Vukicevic for many discussions about science, one of which led in part to the concept of this paper, and P. Gent and P. Rasch for their comments regarding the manuscript. NR 29 TC 16 Z9 16 U1 1 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1463-5003 EI 1463-5011 J9 OCEAN MODEL JI Ocean Model. PY 2000 VL 2 IS 1-2 BP 1 EP 15 AR PII S1463-5003(00)00004-4 DI 10.1016/S1463-5003(00)00004-4 PG 15 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA V22LU UT WOS:000208277500001 ER PT J AU Wickett, ME Duffy, PB Rodrigue, G AF Wickett, M. E. Duffy, P. B. Rodrigue, G. TI A reduced grid for a parallel global ocean general circulation model SO OCEAN MODELLING LA English DT Article DE Ocean modeling; Reduced grid; Spherical grid AB A limitation of many global climate models with explicit finite-difference numerics is the timestep restriction caused by the decrease in cell size associated with the convergence of meridians near the poles. To keep the longitudinal width of model cells as uniform as possible, we apply a "reduced" grid to a three-dimensional primitive equation ocean-climate model. With this grid the number of cells in the longitudinal direction is reduced at high latitudes. The grid consists of subgrids which interact at interfaces along their northern and southern boundaries, where the resolution changes by a factor of three. We extend the finite-difference techniques to these interfaces, focusing on the conservation required to perform long time integrations, while preserving the staggered spatial arrangement of variables and the numerics used on subgrids. The common alternative used to reduce the timestep restriction caused by the spherical grid is the filtering of high-frequency modes from the high-latitude solution. The reduced grid allows an increased timestep while eliminating the need for filtering and reduces execution time per model step by roughly 20%. We implement the reduced grid model for parallel computer architectures with two-dimensional domain decomposition and message passing, with speedup results similar to those of the original model. We present results of model runs showing small effects on the solution and sizable improvements to the execution time. Published by Elsevier Science Ltd. C1 [Wickett, M. E.] Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. [Duffy, P. B.] Lawrence Livermore Natl Lab, Climate & Carbon Cycle Modeling Grp, Livermore, CA 94551 USA. [Rodrigue, G.] Lawrence Livermore Natl Lab, Univ Calif Davis, Livermore, CA 94551 USA. RP Wickett, ME (reprint author), Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. EM wickett@llnl.gov FU US Department of Energy; University of California Lawrence Livermore National Laboratory [W-7405-Eng-48] FX This work was performed under the auspices of the US Department of Energy by University of California Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48. NR 33 TC 8 Z9 8 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1463-5003 EI 1463-5011 J9 OCEAN MODEL JI Ocean Model. PY 2000 VL 2 IS 3-4 BP 85 EP 107 DI 10.1016/S1463-5003(00)00008-1 PG 23 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA V27OE UT WOS:000208621700001 ER PT J AU Vladusic, EA Hornby, AE Guerra-Vladusic, FK Lakins, J Lupu, R AF Vladusic, EA Hornby, AE Guerra-Vladusic, FK Lakins, J Lupu, R TI Expression and regulation of estrogen receptor beta in human breast tumors and cell lines SO ONCOLOGY REPORTS LA English DT Article DE estrogen receptor beta; estradiol; tamoxifen; ICI-182,780; regulation; breast ID CANCER-CELLS; GROWTH-FACTORS; T47D; ANTIESTROGENS; TAMOXIFEN; DOMAINS; ANTAGONISTS; RESISTANCE; CLONING AB Expression of estrogen receptor beta (ER-beta) and its regulation by estradiol and anti-estrogens was analyzed in breast cancer cells. We determined that ER-beta is expressed in normal and tumor human breast tissue as well as in breast cancer cell lines. We observed moderate levels of ER-B expression in both T47D and T47D-V22 (a T47D variant cell line) cells, in contrast with T47DCo (a T47D variant cell line) cells when compared to ER-alpha expression. While T47DCo (a T47D variant cell line), BT474, MDA-MB-231, MDA-MB-453, MDA-MB-468 and MCF-7 express low levels of ER-R, other cell lines including the T47D-Y (a T47D variant cell line), MDA-MB-435, BT-549, and SKBr-3 cells express undetectable levels of ER-D. Interestingly, ER-beta and ER-alpha are apparently not co-expressed in the breast tissue analyzed. Estradiol induced 30-40-fold increased ER-beta mRNA expression in T47D cells over control untreated cells. Moreover, the anti-estrogen, 4-hydroxy-tamoxifen (40H-Tam) strongly inhibited estradiol induction of ER-beta expression, but had little or no effect on estradiol induction of ER-alpha. A pure anti-estrogen, ICI-182,780, completely abolished the ability of estradiol to up-regulate the expression of ER. In addition, both actinomycin D and cyclohexymide inhibited estradiol induction of ER-beta mRNA, indicating that de novo mRNA and protein synthesis are probably required for this induction. In summary, this study demonstrates that ER-beta is expressed in breast cancer, and it is regulated by estradiol. Moreover, the studies demonstrate that estradiol up-regulation of ER-beta mRNA in T47D cells can be abolished by anti-estrogens. Thus, ER-beta expression may serve as a prognostic, diagnostic and/or therapeutic marker for breast cancer. To the best of our knowledge, this is the first report regarding hormonal regulation of ER-beta in human mammary cells. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Lupu, R (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 37 TC 154 Z9 155 U1 0 U2 4 PU PROFESSOR D A SPANDIDOS PI ATHENS PA 1, S MERKOURI ST, EDITORIAL OFFICE,, ATHENS 116 35, GREECE SN 1021-335X J9 ONCOL REP JI Oncol. Rep. PD JAN-FEB PY 2000 VL 7 IS 1 BP 157 EP 167 PG 11 WC Oncology SC Oncology GA 267JL UT WOS:000084354800030 PM 10601611 ER PT S AU Groom, DE AF Groom, DE BE Lye, M Moorwood, AFM TI Recent progress on CCDs for astronomical imaging SO OPTICAL AND IR TELESCOPE INSTRUMENTATION AND DETECTORS, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical and IR Telescope Instrumentation and Detectors CY MAR 27-31, 2000 CL MUNICH, GERMANY SP SPIE, European So Observ, DFM Engn Inc DE CCD; mosaic; high resistivity; fully depleted; PSF; astronomical; fringing; Lawrence Berkeley National Laboratory; Lick Observatory ID ORTHOGONAL-TRANSFER CCD AB We review recent progress in the field, using as a framework a partial list of present limitations and problems: CCD and mosaic size, packing fraction in mosaics, red response and fringing, and intrinsic point-spread function due to lateral charge diffusion. Related topics such as orthogonal-transfer CCDs and the special requirements of adaptive-optics wavefront sensors are also discussed. Only cursory attention is given to other relevant issues, such as readout speed and anti-blooming techniques. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Groom, DE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 26 TC 15 Z9 15 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 0-8194-3633-X J9 P SOC PHOTO-OPT INS PY 2000 VL 4008 BP 634 EP 645 DI 10.1117/12.395522 PN 1&2 PG 12 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ82G UT WOS:000089706500065 ER PT S AU Mourant, JR Canpolat, M Brocker, C Esponda-Ramos, O Johnson, T Matanock, A Stetter, K Freyer, JP AF Mourant, JR Canpolat, M Brocker, C Esponda-Ramos, O Johnson, T Matanock, A Stetter, K Freyer, JP BE Alfano, RR TI Light scattering from cells: the contribution of the nucleus and the effects of proliferative status SO OPTICAL BIOPSY III SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Optical Biopsy III CY JAN 23-24, 2000 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc ID TISSUE DIAGNOSTICS; PROGNOSTIC FACTOR; FLOW-CYTOMETRY; DNA CONTENT; SPECTROSCOPY; FIBROBLASTS; CANCER; PLOIDY AB As part of our ongoing efforts to understand the fundamental nature of light scattering from cells and tissues, we present data on elastic light scattering from isolated mammalian tumor cells and nuclei. The contribution of scattering from internal structures and in particular from the nuclei was compared to scattering from whole cells. Roughly 55% of the elastic light scattering at high-angles (>40 degrees) comes from intracellular structures. An upper limit of 40% on the fractional contribution of nuclei to scattering from cells in tissue was determined. Using cell suspensions isolated from monolayer cultures at different stages of growth, we have also found that scattering at angles greater than about 110 degrees was correlated with the DNA content of the cells. Based on model calculations and the relative size difference of nuclei from cells in different stages of growth, we argue that this difference in scattering results from changes in the internal structures of the nucleus. This interpretation is consistent with our estimate of 0.2 mu m as the mean size of the scattering centers in cells. Additionally, we fmd that while scattering from the nucleus accounts for a majority of internal scattering, a significant portion must result from scattering off of cytoplasmic structures such as mitochondria. C1 Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. RP Mourant, JR (reprint author), Los Alamos Natl Lab, Biosci Div, MS E535, Los Alamos, NM 87545 USA. EM jmourant@lanl.gov NR 26 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 0-8194-3533-3 J9 PROC SPIE PY 2000 VL 3917 BP 33 EP 42 DI 10.1117/12.382747 PG 10 WC Oncology; Engineering, Biomedical; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Oncology; Engineering; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BQ22Z UT WOS:000087646200005 ER PT S AU Demos, SG Staggs, M Radousky, HB Alfano, RR AF Demos, SG Staggs, M Radousky, HB Alfano, RR BE Alfano, RR TI Instrumentation for subsurface imaging in a clinical environment SO OPTICAL BIOPSY III SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Optical Biopsy III CY JAN 23-24, 2000 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE polarization; tissues; backscattering; imaging; fluorescence ID POLARIZATION; TISSUE AB The aim of this effort is to test the feasibility to develop endoscopic optical imaging technology for cancer screening inside the human body. The degree of success of such optical imaging instrumentation depends on the presence of optical differences among the various tissue components of interest of a body part or organ. Our research approach involves the utilization of the spectral polarization difference imaging technique incorporated into endoscopic imaging modalities. To establish methodology for optimum operation, we have build a compact imaging system for in-vitro studies of human tissue samples of interest in a clinical environment. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Demos, SG (reprint author), Lawrence Livermore Natl Lab, POB 808,L-411, Livermore, CA 94551 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 0-8194-3533-3 J9 PROC SPIE PY 2000 VL 3917 BP 62 EP 66 DI 10.1117/12.382716 PG 5 WC Oncology; Engineering, Biomedical; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Oncology; Engineering; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BQ22Z UT WOS:000087646200008 ER PT S AU Thomas, N Wolfe, J AF Thomas, N Wolfe, J BE Dierickx, P TI UV-shifted durable silver coating for astronomical mirrors SO OPTICAL DESIGN, MATERIALS, FABRICATION, AND MAINTENANCE SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Optical Design, Materials, Fabrication, and Maintenance CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE silver coating; uv coating; thin film; Al; Ag; astronomical mirror coating; uv-shifted silver; non-tarnishing ID CORROSION AB Silver has the highest reflectance of all of the metals, but it tarnishes in the presence of sulfides, chlorides, and oxides in the atmosphere. Also, the silver reflectance is very low at wavelengths below 400 Mm making aluminum more desirable mirror coating for the UV region. We have found a way to prevent silver tarnishing by sandwiching the silver layer between two thin layers of NiCrNx, and to extend the metal's high reflectance down to 200 nm by depositing the (thin) Ag layer on top of Al. Thus, the uv is transmitted through the thin Ag layer below 400 nm wavelength, and is reflected from the Al layer underneath. This UV-shifted durable coating(1) provides a valuable alternative to the aluminum coating for telescope mirror coatings where high throughput and durability are important considerations. The throughput for a telescope with, say, six reflections from silver coatings is (0.97)(6) = 83% compared to (0.92)(6) = 60% for aluminum coatings, or 28% less. The use of silver coatings allows more photons to be collected by primary mirror. Aluminum also has a reflectance dip at 850 nm caused by inter-band transitions which is eliminated by placing the thin Ag layer on top. This paper describes a non-tarnishing silver coating having high reflectance down into the UV region. The average specular reflectance is 70% - 97% in the near-UV, 95% - 99% in the visible region, and greater than or equal to 99% in the infrared region covering the total wavelength range 200 nm to 10,000 nm. Figure 1 compares the reflectance of our UVHR-LLNL silver coating to bare silver and aluminum over-coated with magnesium fluoride over the wavelength range 300 nm to 2000 nm. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 21 TC 23 Z9 23 U1 1 U2 7 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3628-3 J9 PROC SPIE PY 2000 VL 4003 BP 312 EP 323 DI 10.1117/12.391537 PG 12 WC Engineering, Manufacturing; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BQ69Z UT WOS:000089218100031 ER PT B AU Groom, DE Eberhard, PH Holland, SE Levi, ME Palaio, NP Perlmutter, S Stover, RJ Wei, M AF Groom, DE Eberhard, PH Holland, SE Levi, ME Palaio, NP Perlmutter, S Stover, RJ Wei, M BE Amico, P Beletic, JW TI Point-spread function in depleted and partially depleted CCDs SO OPTICAL DETECTORS FOR ASTRONOMY II: STATE-OF-THE-ART AT THE TURN OF THE MILLENNIUM SE ASTROPHYSICS AND SPACE SCIENCE LIBRARY LA English DT Proceedings Paper CT 4th European-Southern-Observatory Charge Coupled Devices Workshop on Optical Detectors for Astronomy CY SEP 13-16, 1999 CL GARCHING, GERMANY SP European SO Observ ID SOFT-X-RAY; IMAGERS; ARRAYS AB The point spread function obtainable in an astronomical instrument using CCD readout is limited by a number of factors, among them the lateral diffusion of charge before it is collected in the potential wells. We study this problem both theoretically and experimentally, with emphasis on the thick CCDs on high-resistivity n-type substrates being developed at Lawrence Berkeley National Lab. C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Groom, DE (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6536-4 J9 ASTROPHYS SPACE SC L PY 2000 VL 252 BP 201 EP 216 PG 16 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BR63J UT WOS:000166990000021 ER PT S AU Knowles, DW de Solorzano, CO Jones, A Lockett, SJ AF Knowles, DW de Solorzano, CO Jones, A Lockett, SJ BE Farkas, DL Leif, RC TI Analysis of the 3D spatial organization of cells and sub cellular structures in tissue SO OPTICAL DIAGNOSTICS OF LIVING CELLS III SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Optical Diagnostics of Living Cells III CY JAN 24-25, 2000 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE 3D spatial analysis; tissue organization; tissue segmentation; fluorescence confocal microscopy ID SECTIONS AB Advancements in image analysis have recently made it possible to segment the cells and nuclei, of a wide variety of tissues, from 3D images collected using fluorescence confocal microscopy [Ortiz de Solorzano et at. J. Microscopy 193:212-226, 1999]. This has made it possible to analyze the spatial organization of individual cells and nuclei within the natural tissue context. We present here a spatial statistical method which examines an arbitrary 3D distribution of cells of two different types and determines the probability that the cells are randomly mixed, cells of one type are clustered, or cells of different types are preferentially associated. Beginning with a segmented 3D image of cells (or nuclei), the Voronoi diagram is calculated to indicate the nearest neighbour relationships of the cells. Then, in a test image of the same topology, cells are randomly assigned a type in the same proportions as in the actual specimen and the ratio of cells with nearest neighbours of the same type versus the other types is calculated. Repetition of this random assignment is used to generate a distribution function which is specific for the tissue image. Comparison of the ratios for the actual sample to this distribution assigns probabilities for the conditions defined above. The technique is being used to analyze the organization of genetically normal versus abnormal cells in cancer tissue. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Knowles, DW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, 84-171,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Ortiz de Solorzano, Carlos/G-3278-2010; OI Ortiz de Solorzano, Carlos/0000-0001-8720-0205; Jones, Arthur/0000-0002-8669-9347 NR 7 TC 7 Z9 7 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3537-6 J9 PROC SPIE PY 2000 VL 3921 BP 66 EP 73 DI 10.1117/12.384235 PG 8 WC Cell Biology; Microscopy; Optics SC Cell Biology; Microscopy; Optics GA BQ27N UT WOS:000087772400007 ER PT S AU Paulus, MJ Gleason, SS Sari-Sarraf, H Johnson, DK Foltz, CJ Austin, DW Easterly, ME Michaud, EJ Dhar, MS Hunsicker, PR Wall, JW Schell, M AF Paulus, MJ Gleason, SS Sari-Sarraf, H Johnson, DK Foltz, CJ Austin, DW Easterly, ME Michaud, EJ Dhar, MS Hunsicker, PR Wall, JW Schell, M BE Farkas, DL Leif, RC TI High-resolution x-ray CT screening of mutant mouse models SO OPTICAL DIAGNOSTICS OF LIVING CELLS III SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Optical Diagnostics of Living Cells III CY JAN 24-25, 2000 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE small animal imaging; x-ray; computed tomography ID TRANSMISSION TOMOGRAPHY; COMPUTED-TOMOGRAPHY; SMALL ANIMALS; RECONSTRUCTION; SYSTEM; MICROTOMOGRAPHY; ALGORITHMS; EMISSION AB A dedicated small animal x-ray computed tomography system has been developed to screen mutagenized mice for anatomical phenotypes. The key components of the data acquisition instrumentation are described along with the system performance parameters. Image reconstruction, visualization and segmentation software algorithms are described. Two contrast media regimens are described and representative studies of mice with adipose, soft and skeletal tissue abnormalities are presented. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Paulus, MJ (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 30 TC 13 Z9 13 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3537-6 J9 PROC SPIE PY 2000 VL 3921 BP 270 EP 279 DI 10.1117/12.384221 PG 10 WC Cell Biology; Microscopy; Optics SC Cell Biology; Microscopy; Optics GA BQ27N UT WOS:000087772400030 ER PT J AU Qian, SN Sostero, G Takacs, PZ AF Qian, SN Sostero, G Takacs, PZ TI Precision calibration and systematic error reduction in the long trace profiler SO OPTICAL ENGINEERING LA English DT Article DE long trace profiler; calibration; angle calibration; accuracy; system error; focal error ID HEAT-LOAD MIRROR; DISTORTION PROFILE; PENTA-PRISM; LTP AB The long trace profiler (LTP) has become the instrument of choice for surface figure testing and slope error measurement of mirrors used for 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 Fourier-transform lens using this technique. The use of a 0.03-arcsec-resolution theodolite combined with the sensitivity of the LTP detector system can be used to calibrate the 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 over the whole testing range of the LTP. (C) 2000 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(00)03501-7]. C1 Sincrotrone Trieste, I-34012 Trieste, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Qian, SN (reprint author), Sincrotrone Trieste, SS 14 Km 163,5 Area Sci Pk, I-34012 Trieste, Italy. NR 22 TC 30 Z9 33 U1 7 U2 9 PU SPIE-INT SOCIETY OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, BELLINGHAM, WA 98225 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD JAN PY 2000 VL 39 IS 1 BP 304 EP 310 DI 10.1117/1.602364 PG 7 WC Optics SC Optics GA 273YG UT WOS:000084736500038 ER EF